Polymer composition for tire and pneumatic tire using same

A polymer composition for a tire having an air permeation coefficient of 25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 .multidot.sec.multidot.cmHg (at 30.degree. C.) or less and a Young's modulus of 1 to 500 MPa, including (A) at least 10% by weight, based on the weight of the total polymer component, of at least one thermoplastic resin having an air permeation coefficient of not more than 25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 .multidot.sec.multidot.cmHg (at 30.degree. C.) and a Young's modulus of more than 500 MPa and (B) at least 10% by weight, based on the total weight of the polymer component, of at least one elastomer component having an air permeation coefficient of more than 25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 .multidot.sec.multidot.cmHg (at 30.degree. C.) and a Young's modulus of not more than 500 MPa, wherein the total amount (A)+(B) of the component (A) and the component (B) is not less than 30% by weight based on the weight of the total polymer component, and a pneumatic tire obtained therefrom.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a polymer composition for a tire superior 
in the balance between the resistance to air permeation and the 
flexibility. More specifically it relates to a polymer composition for a 
tire which enables the inner liner layer or other layer for prevention of 
air permeation to be made thinner and the tire to be made lighter, without 
detracting from the retention of air pressure of the pneumatic tire and 
also relates to a pneumatic tire using the above-mentioned composition for 
the air permeation prevention layer. 
The present invention further relates to a pneumatic tire having an air 
permeation prevention layer which is superior in the balance between the 
resistance to air permeation and the flexibility, which is superior in the 
attachment and bonding of the inner liner layer or other air permeation 
prevention layer during the molding and vulcanization of the tire, and 
which enables the inner liner layer or other air permeation prevention 
layer to be made thinner and the tire to be made lighter without 
detracting from the retention of air pressure in the tire. 
2. Description of the Related Art 
The reduction of fuel consumption is one of the major technical problems to 
be solved in the automobile industry. There have been increasingly 
stronger demands for reduction of the weight of the pneumatic tires as 
part of this approach. 
The inner surface of a pneumatic tire is provided with an inner liner layer 
composed of a low gas-permeable rubber such as butyl rubber or halogenated 
butyl rubber so as to enable the tire air pressure to be kept constant. A 
halogenated rubber, however, suffers from a large hysteresis loss. For 
this reason, when after vulcanization of the tire, there are waves formed 
in the inner surface rubber of the carcass layer and the inner liner layer 
in the space between the carcass cords and the inner liner rubber layer 
deforms along with the deformation of the carcass layer, there is the 
problem that the rolling resistance increases. Therefore, in general, the 
inner liner layer (i.e., halogenated butyl rubber) and inner surface 
rubber of the carcass layer are joined through a rubber sheet, which is 
called a tie gum having a small hysteresis loss. Accordingly, in addition 
to the thickness of the inner liner layer of the halogenated butyl rubber, 
there is added the thickness of the tie gum and the layer as a whole 
becomes a thickness of over 1 mm (i.e., 1000 .mu.m). As a result, this 
becomes one factor increasing the weight of the final tire product. 
Various proposals have been made for using various materials, in place of 
the low gas permeable rubber such as butyl rubber, as the inner liner 
layer of the pneumatic tire. For example, Japanese Examined Patent 
Publication (Kokoku) No. 47-31761 discloses the coating of the inner 
surface of a vulcanized tire having a thickness of 0.1 mm or less from a 
solution or dispersion of a synthetic resin such as polyvinylidene 
chloride, a saturated polyester resin, or a polyamide resin having an air 
permeation coefficient (cm.sup.3 (standard 
state)/cm.multidot.sec.multidot.mmHg)) of 10.times.10.sup.-13 or less at 
30.degree. C. and of 50.times.10.sup.-13 or less at 70.degree. C. 
The technique disclosed in this publication is to provide the inner surface 
of the carcass or the inner surface of the inner liner of a vulcanized 
tire with a coating of a synthetic resin having a specific air permeation 
coefficient and making the thickness of the synthetic resin coating of 0.1 
mm or less, but the pneumatic tire described in the publication had a 
problem in the bonding between the rubber and synthetic resin and further 
had a defect of an inner liner layer inferior in moisture resistance (or 
water resistance). 
Japanese Unexamined Patent Publication (Kokai) No. 5-330307 discloses to 
halogenate the inner surface of the tire (using a conventionally known 
chlorination solution, bromine solution, or iodine solution) and form on 
top of that a polymer coating (thickness of 10 to 200 .mu.m) of 
methoxymethylated nylon, a copolymer nylon, a blend of polyurethane and 
polyvinylidene chloride, or a blend of polyurethane and polyvinylidene 
fluoride. 
Further, Japanese Unexamined Patent Publication (Kokai) No. 5-318618 
discloses a pneumatic tire having a thin film of methoxymethylated nylon 
as an inner liner. According to this technique, the inner surface of a 
green tire is sprayed or coated with a solution or emulsion of 
methoxymethylated nylon, then the tire is vulcanized or alternatively the 
inner surface of a vulcanized tire is sprayed or coated with a solution or 
emulsion of methoxymethylated nylon so as to produce a pneumatic tire. 
Even in the art disclosed in these publications, however, the water 
resistances of the thin films are poor and it is difficult to maintain 
uniformity in film thickness. 
Japanese Unexamined Patent Publication (Kokai) No. 6-40207 discloses an 
example of use of a multilayer film having a low air permeation layer 
composed of a polyvinylidene chloride film or ethylene-vinyl alcohol 
copolymer film and a bonding layer comprised of a polyolefin film, 
aliphatic polyamide film, or polyurethane film as the air permeation 
prevention layer of the tire. However, in this system, the low air 
permeation layer lacks flexibility and the film is unable to keep up with 
expansion and contraction during the use of the tire and therefore cracks. 
Further, Japanese Unexamined Patent Publication No. 5-508435 proposes the 
use, as a tire inner liner composition, of a composition including a 
halogen-containing copolymer of a C.sub.4 to C.sub.7 iso-monolefin and 
p-alkylstyrene plus carbon black, a plasticizer oil, and vulcanization 
agent as a tire inner liner, but this inner liner has an insufficient air 
permeation coefficient and is not suitable for reducing the weight of the 
tire. 
As explained above, various materials have been proposed for the inner 
liner layer of a pneumatic tire, in place of butyl rubber, but none has 
yet been commercialized. In particular, no material has yet been developed 
superior in the balance of the resistance to air permeation and 
flexibility required as an inner liner layer of a pneumatic tire or a 
material superior in bonding with rubber. 
SUMMARY OF THE INVENTION 
Accordingly, the object of the present invention is to provide a polymer 
composition for a tire which is optimal for an air permeation prevention 
layer of a pneumatic tire which enables the tire to be made lighter and 
which is bondable with a rubber layer, without detracting from the 
retention of air pressure by the pneumatic tire and a pneumatic tire which 
constructs an air permeation prevention layer using the same. 
Another object of the present invention is to provide a pneumatic tire 
having an air permeation prevention layer which enables the tire to be 
reduced in weight and is superior in the resistance to air permeation and 
the flexibility, without detracting from the retention of air pressure by 
the pneumatic tire, which may be formed even after the molding of the 
tire, and which is superior in the self-attachment (bonding) with the 
superposed films. 
In accordance with the first aspect of the present invention, there is 
provided a polymer composition for a tire having an air permeation 
coefficient of 25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 
.multidot.sec.multidot.cmHg (at 30.degree. C.) or less and a Young's 
modulus of 1 to 500 MPa comprising: 
(A) at least 10% by weight, based on the weight of the total polymer 
component, of at least one thermoplastic resin having an air permeation 
coefficient of 25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 
.multidot.sec.multidot.cmHg (at 30.degree. C.) or less and a Young's 
modulus of more than 500 MPa and 
(B) at least 10% by weight, based on the total weight of the polymer 
component, of at least one elastomer component having an air permeation 
coefficient of more than 25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 
.multidot.sec.multidot.cmHg (at 30.degree. C.) and a Young's modulus of 
not more than 500 MPa, wherein the total amount (A)+(B) of the component 
(A) and the component (B) is not less than 30% by weight based on the 
weight of the total polymer component, and a pneumatic tire using this 
polymer composition for a tire for an air permeation prevention layer. 
In accordance with the second aspect of the present invention, there is 
provided a polymer composition for a tire having an air permeation 
coefficient of 25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 
.multidot.sec.multidot.cmHg (at 30.degree. C.) or less and a Young's 
modulus of 1 to 500 MPa comprising: 
(A) at least 10% by weight, based on the weight of the total polymer 
component, of at least one thermoplastic resin having an air permeation 
coefficient of 25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 
.multidot.sec.multidot.cmHg (at 30.degree. C.) or less and a Young's 
modulus of more than 500 MPa, 
(B) at least 10% by weight, based on the total weight of the polymer 
component, of at least one elastomer component having an air permeation 
coefficient of more than 25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 
.multidot.sec.multidot.cmHg (at 30.degree. C.) and a Young's modulus of 
not more than 500 MPa, wherein the total amount (A)+(B) of the component 
(A) and the component (B) is not less than 30% by weight based on the 
weight of the total polymer component, and 
(C) in the thermoplastic resin of the component (A), 3 to 70% by weight, 
based on the total weight of the components (A), (B), and (C), of another 
thermoplastic resin with a critical surface tension difference of not more 
than 3 mN/m with the facing rubber layer when used as a tire, and a 
pneumatic tire using this polymer composition for a tire for an air 
permeation prevention layer. 
In accordance with the third aspect of the invention, there is provided a 
pneumatic tire using as an air permeation prevention layer a polymer 
composition for a tire having an air permeation coefficient of 
25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 .multidot.sec.multidot.cmHg 
(at 30.degree. C.) or less and a Young's modulus of 1 to 500 MPa 
comprising: 
(A) at least 10% by weight, based on the weight of the total polymer 
component, of at least one thermoplastic resin having an air permeation 
coefficient of 25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 
.multidot.sec.multidot.cmHg (at 30.degree. C.) or less and a Young's 
modulus of more than 500 MPa, 
(B) at least 10% by weight, based on the total weight of the polymer 
component, of at least one elastomer component having an air permeation 
coefficient of more than 25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 
.multidot.sec.multidot.cmHg (at 30.degree. C.) and a Young's modulus of 
not more than 500 Mpa, wherein the total amount (A)+(B) of the component 
(A) and the component (B) is not less than 30% by weight based on the 
weight of the total polymer component, and 
(D) in the thermoplastic resin of the component (A), 3 to 50% by weight, 
based on the total weight of the components (A), (B), and (D), of another 
thermoplastic resin having a melting point not more than the vulcanization 
temperature, and a pneumatic tire having an air permeation prevention 
layer obtained by superposing or coating a surface of a thin film of a 
polymer composition comprised of the components (A) and (B) with another 
thermoplastic resin (D) having a melting point not more than the 
vulcanization temperature, followed by vulcanizing. 
In accordance with the fourth embodiment of the invention, there is 
provided a pneumatic tire obtained by superposing or coating between 
(i) an air permeation prevention layer having an air permeation coefficient 
of 25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 .multidot.sec.multidot.cmHg 
(at 30.degree. C.) or less and a Young's modulus of 1 to 500 MPa, composed 
of (A) at least 10% by weight, based on the weight of the total polymer 
component, of at least one thermoplastic resin having an air permeation 
coefficient of not more than 25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 
.multidot.sec.multidot.cmHg (at 30.degree. C.) and a Young's modulus of 
more than 500 MPa and (B) at least 10% by weight, based on the total 
weight of the polymer component, of at least one elastomer component 
having an air permeation coefficient of more than 25.times.10.sup.-12 
cc.multidot.cm/cm.sup.2 .multidot.sec.multidot.cmHg (at 30.degree. C.) and 
a Young's modulus of not more than 500 MPa, wherein the total amount 
(A)+(B) of the component (A) and the component (B) is not less than 30% by 
weight based on the weight of the total polymer component, and 
(ii) a layer facing at least one surface of the air permeation prevention 
layer 
a layer imparting bondability to the thermoplastic resin and 
having a critical surface tension difference between the layer facing the 
air permeation prevention layer and the bondability imparting layer of not 
more than 3 mN/m; a pneumatic tire wherein the critical surface tension 
difference between the air permeation prevention layer and the bondability 
imparting layer is not more than 3 mN/m; and a process of producing a 
pneumatic tire comprising the steps of: 
superposing or coating between a polymer composition for an air permeation 
prevention layer having an air permeation coefficient of 
25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 .multidot.sec.multidot.cmHg 
(at 30.degree. C.) or less and a Young's modulus of 1 to 500 MPa, 
comprised of (A) at least 10% by weight, based on the weight of the total 
polymer component, of at least one thermoplastic resin having an air 
permeation coefficient of 25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 
.multidot.sec.multidot.cmHg (at 30.degree. C.) or less and a Young's 
modulus of more than 500 MPa and (B) at least 10% by weight, based on the 
total weight of the polymer component, of at least one elastomer component 
having an air permeation coefficient of more than 25.times.10.sup.-12 
cc.multidot.cm/cm.sup.2 .multidot.sec.multidot.cmHg (at 30.degree. C.) and 
a Young's modulus of not more than 500 MPa, wherein the total amount 
(A)+(B) of the component (A) and the component (B) is not less than 30% by 
weight based on the weight of the total polymer component, and a layer 
facing at least one surface of the air permeation prevention layer, a thin 
film of a thermoplastic resin having a critical surface tension difference 
with the layer facing the air permeation prevention layer of not more than 
3 mN/m, then 
processing and vulcanizing the same.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The thermoplastic resins capable of blending in the polymer composition 
according to the present invention as the component (A) may be any 
thermoplastic resin having an air permeation coefficient of 
25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 .multidot.sec.multidot.cmHg 
(at 30.degree. C.) or less, preferably 0.1.times.10.sup.-12 to 
10.times.10.sup.-12 cc.multidot.cm/cm.sup.2 .multidot.sec.multidot.cmHg 
(at 30.degree. C.), and a Young's modulus of more than 500 MPa, preferably 
500 to 3000 MPa. The amount compounded is at least 10% by weight, based on 
the total weight of the polymer component including the resin and rubber, 
preferably 20 to 85% by weight. 
Examples of thermoplastic resins are the following thermoplastic resins and 
any mixtures of them or containing them. 
Polyamide resins (for example, nylon 6 (N6), nylon 66 (N66), nylon 46 
(N46), nylon 11 (N11), nylon 12 (N12), nylon 610 (N610), nylon 612 (N612), 
nylon 6/66 copolymer (N6/66), nylon 6/66/610 copolymer (N6/66/610), nylon 
MXD6 (MXD6), nylon 6T, nylon 6/6T copolymer, nylon 66/PP copolymer, nylon 
66/PPS copolymer, polyester resins (for example, polybutylene 
terephthalate (PBT), polyethylene terephthalate (PET), polyethylene 
isophthalate (PEI), PET/PEI copolymer, polyacrylate (), polybutylene 
naphthalate (PBN), liquid crystal polyester, polyoxyalkylene diimide 
diacid/polybutyrate terephthalate copolymer, and other aromatic 
polyesters), polynitrile resins (for example, polyacrylonitrile (PAN), 
polymethacrylonitrile, acrylonitrile/styrene copolymer (AS), 
methacrylonitrile/styrene copolymer, methacrylonitrile/styrene/butadiene 
copolymer), polymethacrylate resins (for example, polymethyl methacrylate 
(PMMA), polyethyl methacrylate), polyvinyl resins (for example, vinyl 
acetate (EVA), polyvinyl alcohol (PVA), vinyl alcohol/ethylene copolymer 
(EVOH), polyvinylidene chloride (PVDC), polyvinyl chloride (PVC), 
polyvinyl/polyvinyl idene copolymer, vinylidene chloride/methylacrylate 
copolymer), cellulose resins (for example, cellulose acetate, cellulose 
acetate butyrate), fluorine resins (for example, polyvinylidene fluoride 
(PVDF), polyvinyl fluoride (PVF), polychlorofluoroethylene (PCTFE), 
tetrafluoroethylene/ethylene copolymer (ETFE)), imide resins (for example, 
aromatic polyimides (PI)), etc. may be mentioned. 
As explained above, these thermoplastic resins must have specific air 
permeation coefficients, Young's moduluses, and formulations. A material 
having a flexibility of a Young's modulus of 500 MPa or less and an air 
permeation coefficient of 25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 
.multidot.sec.multidot.cmHg (at 30.degree. C.) or less has not yet been 
developed on an industrial basis. Further, when the air permeation 
coefficient is more than 25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 
.multidot.sec.multidot.cmHg (at 30.degree. C.), the resistance to air 
permeation of the polymer composition for a tire is decreased and the 
composition does not function as an air permeation prevention layer of a 
tire. Further, even when the amount of the thermoplastic resin compounded 
is less than 10% by weight, the resistance to air permeation similarly 
declines and the composition does not be used as an air permeation 
prevention layer for a tire. The elastomer component blended into the 
resin composition of the present invention as the component (B) is any 
elastomer having an air permeation coefficient or more than 
25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 .multidot.sec.multidot.cmHg 
(at 30.degree. C.) and Young's modulus of 500 MPa or less or any blend 
thereof or an elastomer composition comprising thereof with necessary 
amounts of the blending agents generally blended with elastomers for the 
improvement of the dispersion, heat resistance, etc. of the elastomers or 
the like, such as reinforcements, fillers, cross-linking agents, softening 
agents, antidegradants, and processing aids. The amount compounded is at 
least 10% by weight, preferably 10 to 85% by weight, based on the total 
weight of the total amount of the polymer component including the resin 
and the elastomer component constituting the air permeation prevention 
layer. 
The elastomer constituting the elastomer component is not particularly 
limited in so far as it has the above-mentioned air permeation coefficient 
and Young's modulus. Examples of such an elastomer component are as 
follows, but mention may be made of the following: 
Diene rubbers and the hydrogenates thereof (for example, NR, IR, epoxylated 
natural rubbers, SBR, BR (high cis BR and low cis BR), NBR, hydrogenated 
NBR, hydrogenated SBR), olefin rubbers (for example, ethylene propylene 
rubber (EPDM, EPM), maleic acid modified ethylene propylene rubbers 
(M-EPM), IIR, isobutylene and aromatic vinyl or diene monomer copolymers, 
acryl rubbers (ACM), and ionomers), halogen-containing rubbers (for 
example, brominated butyl rubbers (Br-IIR), chlorinated butyl rubbers 
(Cl-IIR), brominated isobutylene paramethylstyrene copolymers (Br-IPMS), 
chloroprene rubbers (CR), hydrin rubbers (CHR, CHC), chlorosulfonated 
polyethylenes (CSM), chorinated polyethylenes (CM), maleic acid modified 
chlorinated polyethylenes (M-CM)), silicone rubbers (for example, 
methylvinyl silicone rubbers, dimethyl silicone rubbers, methyl 
phenylvinyl silicone rubbers), sulfur-containing rubbers (for example, 
polysulfide rubbers), fluoro rubbers (for example, vinylidene fluoride 
rubbers, fluorine-containing vinyl ether rubbers, tetrafluoro-ethylene 
propylene rubbers, fluorine-containing silicone rubbers, 
fluorine-containing phosphazen rubbers), thermoplastic elastomers (for 
example, styrene elastomers, polyolefin elastomers, polyester elastomers, 
polyurethane elastomers, polyamide elastomers), etc. 
Note that as the elastomer component, halogen (for example, Br, Cr, 
I)-containing copolymer rubbers such as disclosed in Japanese Unexamined 
Patent Publication (Kokai) No. 5-508435 containing C.sub.4 to C.sub.7 
iso-monoolefin and p-alkylenestyrene, having a content of 
p-alkylenestyrene of 5.5 to 25% by weight of the total copolymer rubber, 
preferably 6.0 to 20% by weight, a halogen content of not less than 1.0% 
by weight or more, preferably 1.0 to 5.0% by weight, and a Mooney 
viscosity ML.sub.1+8 (125.degree. C.) of 30 or more, preferably 35 to 70, 
may be used. The weight ratio of the component (A) and the component (B) 
in the case of use of this rubber is (A)/(B)=10/90 to 90/10, preferably 
15/85 to 85/15. 
A content of p-alkylenestyrene of this copolymer rubber of less than 5.5% 
by weight is not desirable, since the resistance to air permeation of the 
resultant polymer composition for a tire is decreased, while the copolymer 
rubber having more than 25% by weight is not desirable, since the 
embrittlement tends to occur at low temperatures. Further, a halogen 
content of less than 1.0% by weight is not desirable, since the mechanical 
strength such as the tensile strength falls, while a Mooney viscosity of 
less than 30 is not desirable, since again the resistance to air 
permeation is decreased. Further, a compounding ratio of the component (A) 
and component (B) (based on weight) of less than 10/90 is not desirable 
since again the resistance to air permeation falls, while conversely one 
over 90/10 is not desirable since the flexibility is decreased. 
Note that one example of such a copolymer rubber is sold commercially as 
EXXPRO from Exxon Chemical. For example, this is obtained by partially 
brominating a copolymer rubber of an isoprene and p-methylstyrene of the 
structure (A) shown below by Br.sub.2 to obtain the copolymer rubber of 
the following structure (B). This may be suitably used in the present 
invention. 
##STR1## 
When the compatibilities of the above-mentioned specific thermoplastic 
resin and elastomer component are different, it is preferable to use a 
suitable agent for promoting compatibility as a third component so as to 
cause the two components to become compatible with each other. Mixing such 
a compatibility agent into the system enables the surface tension between 
the thermoplastic resin and the elastomer component to be lowered and, as 
a result, makes the rubber particles forming the dispersion layer smaller 
in size, so the characteristics of the two components are more effectively 
brought out. Examples of such a compatibility agent are a copolymer having 
the structure of one or both of the thermoplastic resin and elastomer 
component or one having the structure of a copolymer having a group 
reactable with the thermoplastic resin or elastomer component such as an 
epoxy group, carboxyl group, halogen group, amine group, oxazoline group, 
hydroxyl group, etc. These may be selected according to the type of the 
thermoplastic resin and elastomer component to be mixed in with, but 
normally use is made of a styrene/ethylene/butadiene-styrene block 
copolymer (SEBS) and its maleic acid modified products, EPDM, EPDM/stryene 
or EPDM/acrylonitrile graft copolymers and their maleic acid modified 
products, styrene/maleate copolymers, reactive phenoxy resins, etc. The 
amount of the compatibility agent is not particularly limited, but 
preferably is 0.5 to 20 parts by weight based on 100 parts of the polymer 
component (total of thermoplastic resin and elastomer component). 
The proportion of the specific thermoplastic resin (A) and elastomer 
component (B) may be suitably determined by the balance of the thickness 
of the film, the resistance to air permeation, and the flexibility, but a 
preferable range is, by weight ratio, 10/90 to 90/10, more preferably 
20/80 to 85/15. 
The polymer composition according to the present invention may have mixed 
into it, as a third component in addition to the polymer component of the 
above necessary components (A) and (B), another polymer such as the above 
compatibility agent polymer in a range not detracting from the required 
properties of the polymer composition for a tire of the present invention. 
The purpose of mixing in the other polymer is to improve the compatibility 
of the thermoplastic resin and the elastomer composition, to improve the 
film forming ability of the material, to improve the heat resistance, to 
reduce costs, etc. Examples of such materials used for these purposes are 
polyethylene (PE), polypropylene (PP), polystyrene (PS), ABS, SBS, and 
polycarbonate (PC). The polymer of the third component (C) is not 
particularly limited so long as the polymer composition has the 
predetermined values of the air permeation coefficient and Young's 
modulus. 
The polymer composition according to the present invention, as explained 
above, includes as essential components the polymer components (A) and (B) 
having the specific air permeation coefficient and Young's modulus. This 
may be illustrated as in the graph of FIG. 1. In FIG. 1, the component (A) 
corresponds to the area X, the component (B) to the area Y, and the 
resultant polymer composition to the area Z. 
In the present invention, the thermoplastic resins A.sub.1 to A.sub.n 
belonging to the component (A) are determined (here, A.sub.1 is expressed 
as (A.sub.ix, A.sub.iy) where the Young's modulus of the i-th 
thermoplastic resin is A.sub.ix and the air permeation coefficient is 
A.sub.iy) and the average value Aav of the same (=.SIGMA..phi.i (A.sub.ix, 
A.sub.iy) (i=1 to n), where .phi.i is the percentage by weight of Ai) is 
found. An elastomer is selected so that the average Bav (=.SIGMA..phi.i 
(B.sub.ix, B.sub.iy) (i=1 to n), where .phi.i is the percent by weight of 
Bi, B.sub.ix is the Young's modulus of the i-th elastomer component, and 
B.sub.iy is the air permeation coefficient of the i-th elastomer 
component) of the (B) components B.sub.1 to B.sub.n falling in the area Y 
falls in the area S under the line obtained by extending outward the 
straight line AavP connecting the point Aav and the point P of the air 
permeation coefficient of 25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 
.multidot.sec.multidot.cmHg (at 30.degree. C.) and the Young's modulus of 
500 MPa and above the air permeation coefficient of 25.times.10.sup.-12 
cc.multidot.cm/cm.sup.2 .multidot.sec.multidot.cmHg (at 30.degree. C.). By 
mixing the component (A) and the component (B) in a suitable formulation, 
it is possible to obtain a polymer composition falling in the target area 
Z. 
The pneumatic tire having the air permeation prevention layer produced 
using the polymer composition for a tire of the present invention will now 
be explained in further detail. 
The air permeation prevention layer of the pneumatic tire according to the 
present invention may be arranged at any location inside the tire, that 
is, at the inside or outside of the carcass layer or at any other 
location. The point is that it be arranged so as to prevent the permeation 
and dispersion of air from the inside of the tire and enable the air 
pressure inside the tire to be held for a long period of time, whereby the 
object of the invention can be achieved. 
FIG. 2 is a semi-cross-sectional view along the meridian direction 
illustrating a typical example of the arrangement of an air permeation 
prevention layer of a pneumatic tire. In FIG. 2, a carcass layer 2 spans 
between the left and right bead cores 1 and 1. On the tire inner surface 
at the inside of the carcass layer 2 is provided an inner liner layer 3. 
The inner liner layer 3 is comprised by the above-mentioned tire polymer 
composition in the present invention. In FIG. 2, 4 shows a sidewall. 
The process of production of the polymer composition for making the air 
permeation prevention layer in the present invention consists of melting 
and kneading the thermoplastic resin and elastomer composition 
(unvulcanized in case of rubber) in advance by a bi-axial kneader and 
extruder to cause the elastomer component to disperse in the thermoplastic 
resin forming the continuous phase. When vulcanizing the elastomer 
composition, it is also possible to add the vulcanization agent while 
kneading and perform dynamic vulcanization of the elastomer composition. 
Further, the various blending agents (except vulcanization agent) for the 
thermoplastic resin or the elastomer composition may be added into the mix 
during the kneading, but it is desirable to premix them before the 
kneading. The kneader used for kneading the thermoplastic resin and the 
elastomer composition is not particularly limited. A screw extruder, 
kneader, Bambury mixer, bi-axial kneader and extruder, etc. may be 
mentioned. Among these, a bi-axial kneader and extruder is preferably used 
for kneading of the thermoplastic resin and elastomer composition and for 
dynamic vulcanization of the elastomer composition. Further, it is 
possible to use two or more types of kneaders and successively perform the 
kneading. The condition for the melt kneading is a temperature of at least 
the temperature where the thermoplastic resin melts. Further, a shear rate 
at the time of kneading of 1000 to 7500 sec.sup.-1 is preferable. The 
overall kneading time is from 30 seconds to 10 minutes. Further, when a 
vulcanization agent is added, the vulcanication time after the addition is 
preferably 15 seconds to 5 minutes. 
Note that the types of the vulcanization agents and the dynamic 
vulcanization conditions (i.e., temperature and time), etc. can be 
appropriately determined, depending upon the component (B) added and are 
not specifically limited. 
As the vulcanization agent, any conventional rubber vulcanization agent (or 
crosslinking agent) can be used. Examples of typical sulfur based 
vulcanization agent are sulfur powder, precipitating sulfur, highly 
dispersible sulfur, surface treated sulfur, non-soluble sulfur, dimorforin 
disulfide, alkylphenol disulfide, etc. These vulcanization agent may be 
used in an amount of, for example, 0.5 to 4 phr (i.e., parts by weight per 
100 parts by weight of rubber component (polymer) in the component B). 
Examples of organic peroxide based vulcanization agent are benzoyl 
peroxide, t-butyl/hydroperoxide, 2,4-dichlorobenzoyl peroxide, 
2,5-dimethyl-2,5-di(t-butylperoxy)hexane, 
2,5-dimethylhexane-2,5-di(peroxyl benzoate), etc. and may be used in an 
amount of, for example, 1-15 phr. 
Further, examples of phenol resin based vulcanization agent are brominated 
alkylphenol resins and mixed crosslinking system of halogen donor such as 
tin chloride, chloroprene, etc. and alkyl phenol resin in an amount of, 
for example, 1 to 20 phr. 
As the other vulcanization agents, zinc oxide (about 5 phr), magnesium 
oxide (about 4 phr), litharge (about 10-20 phr), p-quinone dioxime, 
p-dibenzoylquinone dioxime, tetrachloro-p-benzoquinone, poly-p-dinitroso 
benzene (about 2-10 phr), methylene dianiline (0.2-10 phr). 
Furthermore, vulcanization accelerators may be optionally added. Examples 
of such a vulcanization accelerator are conventional vulcanization 
accelerators such as aldehyde.cndot.ammonia type, quanidine type, thiazol 
type, sulfoneamide type, thiuram type, dithioacid salt type, thiourea type 
and these may be used in an amount of, for example, 0.5 to 2 phr. 
As typical examples, hexamethylenetetramine etc. as the 
aldehyde.cndot.ammonia type vulcanization accelerator; diphenylquanidine, 
etc. as the quanidine type vulcanization accelerator; dibenzothiazyl 
disulfide (DM), 2-mercapto benzothiazole and the Zn salt thereof, 
cyclohexylamine salts, etc. as the thiazole type vulcanization 
accelerator; cyclohexyl/benzothiazyl sulfonamide (CBS), N-oxydiethylene 
benzothiazyl-2-sulfenamide, N-t-butyl-2-benzothiazole sulfenamide, 
2-(molpholinoldithio)benzothiazol, etc. as the sulfenamide type 
vulcanization accelerator; tetramethyl thiuramdisulfide (TMTD), tetraethyl 
thiuram disulfide, tetramethyl thiuram monosulfide (TMTM), 
dipentamethylene thiuram tetrasulfide, etc., as the thiuram type 
vulcanization accelerator; Zn-dimethyl-dithiocarbamate, 
Zn-diethyldithiocarbamate, Zn-di-n-butyldithiocarbamate, Zn-ethylphenyl 
dithiocarbamate, Te-diethyl/dithiocarbamate, Cu-dimethyl dithiocarbamate, 
Fe-dimethyl dithiocarbamate, pipecholine pipecholyl dithiocarbamate, etc. 
as the dithio acid salt type vulcanization accelerator, and ethylene 
thiourea, diethyl thiourea, etc. as the thiourea type vulcanization 
accelerator are exemplified. 
The vulcanization accelerator may be used, together with conventional 
rubber additives such as zinc oxide (about 5 phr), stearic acid, oleic 
acid and these Zn salts (about 2-4 phr). 
The polymer composition produced by the above-mentioned process is then 
formed into a film by extrusion or calendering. The method of forming the 
film may be the method for forming a film from an ordinary thermoplastic 
resin or thermoplastic elastomer. 
The thin film thus obtained has a structure of the elastomer composition 
(B) dispersed as a discontinuous phase in a matrix of the thermoplastic 
resin (A). By adopting this state of a dispersed structure, it becomes 
possible to impart a balance of flexibility and resistance to air 
permeation and possible to obtain the effects of an improvement of the 
resistance to heat deformation, improvement of the water resistance, etc. 
Further, thermoplastic working becomes possible. Accordingly, formation of 
a film becomes possible by ordinary plastic molding machines, that is, 
extrusion or calendering. The method of forming the film need only be a 
method for forming a film from an ordinary thermoplastic resin or 
thermoplastic elastomer. 
Regarding the production process of a pneumatic tire having an air 
permeation prevention layer comprised of a thin film of the polymer 
composition according to the present invention, as shown in FIG. 2, 
explaining the example of the case of arranging the inner liner layer 3 at 
the inside of the carcass layer 2, the polymer composition of the present 
invention is extruded to a thin film of a predetermined width and 
thickness by a resin extruder, then this is wrapped around a tire molding 
drum and joined to make a cylindrical shape. On top of this are then 
successively overlaid a carcass layer, a belt layer, a tread layer, and 
other members comprised of unvulcanized rubber used for the production of 
usual tires, then the drum is withdrawn to obtain a green tire. Next, this 
green tire is heated and vulcanized according to an ordinary method to 
make a desired light weight pneumatic tire. Note that the same type of 
process may be followed even when providing the air permeation prevention 
layer on the outer circumference of the carcass layer. 
The material of the rubber layer for bonding with the air permeation 
prevention layer according to the present invention is not particularly 
limited. Any rubber material which has been generally used as a rubber 
material for a tire in the past may be used. Examples of such a rubber are 
rubber compositions comprised of diene rubbers such as NR, IR, BR, and 
SBR, halogenated butyl rubbers, ethylene-propylene copolymer rubbers, 
styrene elastomers, etc. to which have been added blending agents such as 
carbon black, process oil, and vulcanization agents. 
The air permeation prevention layer according to the present invention has 
an air permeation coefficient of 25.times.10.sup.-12 
cc.multidot.cm/cm.sup.2 .multidot.sec.multidot.cmHg (at 30.degree. C.) or 
less, preferably 5.times.10.sup.-12 cc.multidot.cm/cm.sup.2 
.multidot.sec.multidot.cmHg. There is no particular lower limit on the air 
permeation coefficient, but in practice it is 0.05.times.10.sup.-12 
cc.multidot.cm/cm.sup.2 .multidot.sec.multidot.cmHg (at 30.degree. C.) or 
less. By making the air permeation coefficient 25.times.10.sup.-12 
cc.multidot.cm/cm.sup.2 .multidot.sec.multidot.cmHg (at 30.degree. C.) or 
less, it is possible to make the thickness of the air permeation 
prevention layer 1/2 or less the thickness of the conventional air 
permeation prevention layer. 
On the other hand, the Young's modulus is 1 to 500 MPa, preferably 10 to 
300 MPa, and the thickness is 0.02 to 1.0 mm, preferably 0.05 to 0.5 mm. 
When the Young's modulus is less than 1 MPa, then wrinkles will form at 
the time of forming the tire, whereby handling will become difficult, 
while when more than 500 MPa, it is not possible for the film to follow 
the deformation of the tire during use. 
According to the second aspect of the present invention, in addition to the 
above first and second components (A) and (B), a third component for 
imparting bondability comprised of a thermoplastic resin having a critical 
surface tension difference (.DELTA..gamma.c) with the facing rubber layer 
at the time of use as a tire of not more than 3 mN/m is mixed into the 
composition in an amount of 3 to 70% by weight, preferably 3 to 50% by 
weight, based on the total weight of the components (A), (B), and (C). 
When the amount compounded is too small, the bonding with the facing 
component becomes insufficient, while conversely if too great, the air 
permeation coefficient becomes too large and the elasticity becomes too 
high, making this impractical. 
Specific examples of the thermoplastic resin of the third component (C) 
according to the second aspect of the present invention are an ultra high 
molecular weight polyethylene (UHMWPE) having a molecular weight of 
1,000,000 or more, preferably 3,000,000 or more, ethylene-ethylacetate 
copolymer (EEA), ethylene-acrylate copolymer (EAA), 
ethylene-methylacrylate resin (EMA), and other acrylate copolymers and the 
maleic acid addition products thereof, polypropylene (PP), 
styrene-butadiene-styrene block copolymer (SBS), 
styrene-ethylene-butadiene-styrene block copolymer (SEBS), polyethylene 
(PE), ethylene-propylene copolymer (EP), etc. 
The proportion of the total weight of the specific thermoplastic resin 
components (A) and (C) and the elastomer component (B) is suitably 
determined by the balance of the thickness of the film, the resistance to 
air permeation, and the flexibility, but the preferable range is 10/90 to 
90/10, more preferably 20/80 to 85/15. 
The polymer composition according to the present invention, as explained 
above, includes as essential components the polymer components (A), (B), 
and (C) having the specific air permeation coefficient and Young's 
modulus. This may be illustrated as in the graph of FIG. 1. In FIG. 1, the 
component (A) corresponds to the area X, the component (B) to the area Y, 
and the resultant polymer composition to the area Z. The component (C) is 
determined based on having a critical surface tension difference with the 
facing rubber layer of not more than 3 mN/m. 
In the present invention, the thermoplastic resins A.sup.1 to A.sup.n 
belonging to the component (A) are determined and the average value Aav of 
the same (=.SIGMA..phi.i (A.sub.ix, A.sub.iy) (i=1 to n), where .phi.i is 
the percentage by weight of Ai) is found. An elastomer is selected so that 
the average Bav (=.SIGMA..phi.i (i=1 to n), where .phi.i is the percent by 
weight of Bi) of the (B) components B.sub.1 to B.sub.n falling in the area 
Y falls in the area S under the line obtained by extending outward the 
straight line AavP connecting the point Aav and the point P of the air 
permeation coefficient of 25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 
.multidot.sec.multidot.cmHg (at 30.degree. C.) and the Young's modulus of 
500 MPa and above the air permeation coefficient of 25.times.10.sup.-12 
cc.multidot.cm/cm.sup.2 .multidot.sec.multidot.cmHg (at 30.degree. C.). By 
mixing these in a suitable formulation and further adding the component 
(C), it is possible to obtain a polymer composition falling in the target 
area Z. 
The pneumatic tire having the air permeation prevention layer produced 
using the polymer composition for a tire of the second aspect of the 
present invention will now be explained in further detail. 
The production process of the polymer composition for making the air 
permeation prevention layer in the present invention comprises melting and 
kneading the thermoplastic resin component constituted by the components 
(A) and (C) and the elastomer (unvulcanized in case of rubber) component 
(B) in advance by a bi-axial kneader and extruder to cause the elastomer 
component to disperse in the thermoplastic resin forming the continuous 
phase. When vulcanizing the elastomer component, it is also possible to 
add the vulcanization agent while kneading and perform dynamic 
vulcanization of the elastomer component. Further, the various blending 
agents (except vulcanization agent) for the thermoplastic resin or the 
elastomer component may be added into the mix during the kneading, but it 
is desirable to premix them before the kneading. The kneader used for 
kneading the thermoplastic resin and the elastomer is not particularly 
limited. A screw extruder, kneader, Bambury mixer, bi-axial kneader and 
extruder, etc. may be mentioned. Among these, a bi-axial kneader and 
extruder is preferably used for kneading of a resin component and a rubber 
component and for dynamic vulcanization of a rubber component. Further, it 
is possible to use two or more types of kneaders and successively perform 
the kneading. The condition for the melt kneading is a temperature of at 
least the temperature where the thermoplastic resin melts. Further, a 
shear rate at the time of kneading of 2500 to 7500 sec.sup.-1 is 
preferable. The overall kneading time is from 30 seconds to 10 minutes. 
Further, when a vulcanization agent is added, the vulcanication time after 
the addition is preferably 15 seconds to 5 minutes. The polymer 
composition produced by the above-mentioned process is then formed into a 
film by extrusion or calendering. The method of forming the film may be 
the method for forming a film from an ordinary thermoplastic resin or 
thermoplastic elastomer. 
The thin film thus obtained has a structure of at least part of the 
elastomer component (B) dispersed, as a discontinuous phase, in a matrix 
of the thermoplastic resins (A) and (C). 
By adopting this state of a dispersed structure, it becomes possible to 
impart a balance between the flexibility and the resistance to air 
permeation and possible to obtain the effects of an improvement of the 
resistance to heat deformation, improvement of the water resistance, etc. 
Further, thermoplastic processing becomes possible. Accordingly, a film 
formation becomes possible by ordinary plastic molding machines, that is, 
extrusion or calendering. The method of forming the film can be a method 
for forming a film from an ordinary thermoplastic resin or thermoplastic 
elastomer. 
Regarding the production process of a pneumatic tire having an air 
permeation prevention layer comprised of a thin film of the polymer 
composition according to the second aspect of the present invention, as 
shown in FIG. 2, explaining the example of the case of arranging the inner 
liner layer 3 at the inside of the carcass layer 2, the polymer 
composition of the present invention is extruded to a thin film of a 
predetermined width and thickness by a resin extruder, then this is 
wrapped around a tire molding drum and joined to make a cylindrical shape. 
On top of this are then successively superposed a carcass layer, a belt 
layer, a tread layer, and other members including unvulcanized rubber used 
for the production of usual tires, then the drum is withdrawn to obtain a 
green tire. Next, this green tire is heated and vulcanized in accordance 
with an ordinary method to make a desired light weight pneumatic tire. 
Note that the same type of process may be followed even when providing the 
air permeation prevention layer on the outer circumference of the carcass 
layer. 
The material of the rubber layer for facing with the air permeation 
prevention layer according to the present invention is not particularly 
limited. Any rubber material which has been generally used, as a rubber 
material for a tire in the past, may be used. Examples of such a rubber 
are rubber compositions including diene rubbers such as NR, IR, BR, and 
SBR, halogenated butyl rubbers, ethylene-propylene copolymer rubbers, 
styrene elastomers, etc. to which have been added blending agents such as 
carbon black, process oil, and vulcanization agents. 
The air permeation prevention layer according to the present invention has 
an air permeation coefficient of 25.times.10.sup.-12 
cc.multidot.cm/cm.sup.2 .multidot.sec.multidot.cmHg (at 30.degree. C.) or 
less, preferably 5.times.10.sup.-12 cc.multidot.cm/cm.sup.2 
.multidot.sec.multidot.cmHg (at 30.degree. C.) or less. By making the air 
permeation coefficient of 25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 
.multidot.sec.multidot.cmHg (at 30.degree. C.) or less, it is possible to 
make the thickness of the air permeation prevention layer of 1/2 or less 
of the thickness of the conventional air permeation prevention layer. 
On the other hand, the Young's modulus is 1 to 500 MPa, preferably 10 to 
300 MPa, and the thickness is 0.02 to 1.0 mm, preferably 0.05 to 0.5 mm. 
When the Young's modulus is less than 1 MPa, then wrinkles will form at 
the time of forming the tire, whereby handling will become difficult, 
while when more than 500 MPa, it is not possible for the film to follow 
the deformation of the tire during use. 
According to the third aspect of the present invention, in addition to the 
above components (A) and (B), a third component (D) for imparting 
bondability composed of another thermoplastic resin having a melting point 
of the vulcanization temperature or less, preferably 230.degree. C. or 
less, is mixed into the thermoplastic resin of the component (A) in an 
amount of 3 to 50% by weight, preferably 5 to 35% by weight, based on the 
100 parts by weight of the total components. When the amount compounded is 
too small, the attachment and bonding by the heat of vulcanization with 
the polymer composition film after the vulcanization of the green tire 
become insufficient and the joined portions become opened, which is 
inconvenient, in terms of durability, while conversely when too large, the 
molding of the tire becomes difficult due to the fluidity of the 
thermoplastic resin or it becomes difficult to maintain uniformity in the 
thickness of the film due to flow during vulcanization. 
Specific examples of the thermoplastic resin of the third component (D) 
according to the third aspect of the present invention are of an ultra 
high molecular weight polyethylene (UHMWPE) with a weight average 
molecular weight of at least 1,000,000, preferably at least 3,000,000, 
ethylene-acrylester copolymer (EEA), ethylene-methylacrylate resin (EMA), 
ethylene-acrylate copolymer (EAA), and other acrylate copolymers and the 
maleic acid addition products thereof, multiple copolymer polyamide resins 
(PA), ethylene-vinyl acetate copolymer (EVA), etc. Here, the multiple 
copolymer polyamide resins mean two nylons of a specific copolymerization 
ratio, for example, nylon 6/nylon 66 (for example, copolymerization ratio 
of 70/30 to 50/50) and further a three, four, or higher component 
copolymer polyamide such as nylon 6/nylon 66/nylon 610, nylon 6/nylon 
66/nylon 12, nylon 6/nylon 66/nylon 610/nylon 12, etc. These multiple 
copolymer polyamide resins may be used alone or together. These multiple 
copolymer polyamide resins are commercially available, for example, as 
Toray's CM4000, CM4001, CM8000, etc. In addition, polypropylene (PP), 
ethylene-propylene copolymer (EP), styrene-ethylene-butadiene-styrene 
block copolymer (SEBS), styrene-butadiene-styrene block copolymer (SBS), 
styrene-isobutylene-styrene copolymer (SIBS), etc. can be exemplified. 
The polymer composition according to the third aspect of the present 
invention may further have blended therein the above specific 
thermoplastic resin (D), but the resultant polymer composition must have 
the specified air permeation coefficient and Young's modulus. 
When bonding the tire polymer composition according to the third aspect of 
the present invention with rubber, it is of course possible to treat the 
surface of the rubber by a halogen compound or to use the chlorinated 
rubber type, isocyanate type, or phenol resin type adhesive, but in the 
present invention, it is also possible to add the third component (D) of 
another thermoplastic resin and make joint use of a material, which is 
generally called a compatibility agent so as to strengthen the bonding 
power with the rubber. As the compatibility agent, one which functions by 
the action of bringing together the surface energies of the layers may be 
used or one which has reactive functional groups may be used. As the 
reactive group, use is suitably made of the carboxyl group, halogen group, 
hydroxyl group, amine group, epoxy group, etc. As the main compatibility 
agents, mention may be made of maleic acid modified polyolefin, polymers 
comprised of a polyolefin to which acrylate or glycidylmethacrylate has 
been graft polymerized, block copolymers of polyolefins and nylon, and 
maleic acid modified products of a styrene-ethylene-butadiene-styrene 
copolymer. 
The pneumatic tire having the air permeation prevention layer produced 
using the polymer composition for a tire of the third aspect of the 
present invention will be explained in further detail. 
The production process of the polymer composition for making the air 
permeation prevention layer in the present invention comprises melting and 
kneading the thermoplastic resins (A) and (D) and the elastomer 
(unvulcanized in case of rubber) component (B) in advance by a bi-axial 
kneader and extruder to cause the elastomer component to disperse in the 
thermoplastic resin forming the continuous phase. Further, it is possible 
to melt and knead (A) and (B), then add (D) and obtain a similar 
structure. When vulcanizing the elastomer component, it is also possible 
to add the vulcanization agent while kneading and perform dynamic 
vulcanization of the elastomer component. Further, the various blending 
agents (except vulcanization agent) for the thermoplastic resin or the 
elastomer component may be added into the mix during the kneading, but it 
is desirable to premix them before the kneading. The kneader used for 
kneading the thermoplastic resin and the elastomer is not particularly 
limited. A screw extruder, kneader, Bambury mixer, bi-axial kneader and 
extruder, etc. may be mentioned. Among these, a bi-axial kneader and 
extruder is preferably used for kneading of a resin component and a rubber 
component and for dynamic vulcanization of a rubber component. Further, it 
is possible to use two or more types of kneaders and successively perform 
the kneading. The condition for the melt kneading is a temperature of at 
least the temperature where the thermoplastic resin melts. Further, a 
shear rate at the time of kneading of 2500 to 7500 sec.sup.-1 is 
preferable. The overall kneading time is from 30 seconds to 10 minutes. 
Further, when a vulcanization agent is added, the vulcanication time after 
the addition is preferably 15 seconds to 5 minutes. The polymer 
composition produced by the above process is then extruded into strands by 
a bi-axial kneader and extruder which are then pelletized by a resin 
pelletizer, then the pellets are used for sheeting or calendering by a 
resin extruder to form a film. The method of forming the film may be the 
method for forming a film from an ordinary thermoplastic resin or 
thermoplastic elastomer. 
The thin film thus obtained has a structure of at least part of the 
elastomer component (B) dispersed as a discontinuous phase in a matrix of 
the thermoplastic resins (A) and (D). By adopting this state of a 
dispersed structure, it becomes possible to impart a balance between 
flexibility and resistance to air permeation and possible to obtain the 
effects of an improvement of the resistance to heat deformation, 
improvement of the water resistance, etc. Further, thermoplastic working 
becomes possible. Accordingly, formation of a film becomes possible by 
ordinary plastic molding machines, that is, extrusion or calendering. The 
method of forming the film can be a method for forming a film from an 
ordinary thermoplastic resin or thermoplastic elastomer. 
Regarding the production process of a pneumatic tire having an air 
permeation prevention layer comprising a thin film of the polymer 
composition according to the third aspect of the present invention, as 
shown in FIG. 2, explaining the example of the case of arranging the inner 
liner layer 3 at the inside of the carcass layer 2, the polymer 
composition of the present invention is extruded to a thin film of a 
predetermined width and thickness by a resin extruder, then this is 
wrapped around a tire molding drum and joined to make a cylindrical shape. 
On top of this are then successively overlaid a carcass layer, a belt 
layer, a tread layer, and other members comprised of unvulcanized rubber 
used for the production of usual tires, then the drum is withdrawn to 
obtain a green tire. Next, this green tire is heated and vulcanized in 
accordance with an ordinary method at, for example, 150.degree. C. to 
230.degree. C. to make a desired light weight pneumatic tire. Note that 
the same type of process may be followed even when providing the air 
permeation prevention layer on the outer circumference of the carcass 
layer. 
The material of the rubber layer for facing the air permeation prevention 
layer according to the present invention is not particularly limited. Any 
rubber material which has been generally used as a rubber material for a 
tire in the past may be used. Examples of such a rubber are rubber 
compositions including diene rubbers such as NR, IR, BR, and SBR, 
halogenated butyl rubbers, ethylene-propylene copolymer rubbers, styrene 
elastomers, etc. to which have been added blending agents such as carbon 
black, process oil, and vulcanization agents. 
The air permeation prevention layer according to the present invention has 
an air permeation coefficient of 25.times.10.sup.-12 
cc.multidot.cm/cm.sup.2 .multidot.sec.multidot.cmHg (at 30.degree. C.) or 
less, preferably 5.times.10.sup.-12 cc.multidot.cm/cm.sup.2 
.multidot.sec.multidot.cmHg (at 30.degree. C.) or less. By making the air 
permeation coefficient 25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 
.multidot.sec.multidot.cmHg (at 30.degree. C.) or less, it is possible to 
make the thickness of the air permeation prevention layer 1/2 or less of 
the thickness of the conventional air permeation prevention layer. 
On the other hand, the Young's modulus is 1 to 500 MPa, preferably 10 to 
300 MPa, and the thickness is 0.02 to 1.0 mm, preferably 0.05 to 0.5 mm. 
When the Young's modulus is less than 1 MPa, then wrinkles will form at 
the time of forming the tire, whereby handling will become difficult, 
while when more than 500 MPa, it is not possible for the film to follow 
the deformation of the tire during use. 
According to the third aspect of the present invention, in addition to the 
polymer component of the above essential components (A) and (B), it is 
also possible to blend, as the third component (E), to an extent not 
detracting from the required properties of the polymer composition for a 
tire of the present invention a compatibility agent or other polymer and 
blending agents. The purpose of blending another polymer is to improve the 
compatibility of the thermoplastic resin component and a rubber component, 
to improve the film forming ability of the material, to improve the heat 
resistance, to reduce costs, etc. Examples of materials used for these 
purposes are polyethylene, polypropylene, polystyrene, ABS, SBS, and 
polycarbonate (PC). The polymer of the third component (E) is not 
particularly limited so long as the polymer composition has the 
predetermined values of the air permeation coefficient and Young's 
modulus. 
Even when the critical surface tension difference beween the air permeation 
prevention layer and the bondability imparting layer is more than 3 mN/m, 
by suitably selecting the compatibility agent, it is possible to adjust 
the bonding. As such a compatibility agent, mention may be made of maleic 
acid modified polyolefins, polymers composed of a polyolefin to which 
acrylate or glycidylmethacrylate has been graft polymerized, block 
copolymers of polyolefins and nylon, and maleic acid modified products of 
a styrene-ethylene-butadiene-styrene copolymer. 
According to the fourth aspect of the present invention, as a bondability 
imparting layer for improving the bonding with the facing layer at least 
at one surface of the air permeation prevention layer, a thin film of a 
thermoplastic resin different from the thermoplastic resin (A) and having 
a critical surface tension difference with the layer facing the air 
permeation prevention layer of 3 mN/m or less or a critical surface 
tension difference (.DELTA..gamma.c) with the two layers of 3 mN/m or less 
is used. The thickness is not particularly limited, but the preferable 
thickness is 250 .mu.m or less. 
By doing this, there is an entanglement action of the thermoplastic resin 
with the facing layers during vulcanization, and therefore the bonding is 
achieved. 
Specific examples of the bonding polymer constituting the bondability 
imparting layer having the specified critical surface tension difference 
according to the present invention are an ultra high molecular weight 
polyethylene (UHMWPE) with a weight average molecular weight of at least 
1,000,000, preferably at least 3,000,000, ethylene-ethylacrylate copolymer 
(EEA), ethylene-methylacrylate resin (EMA), ethylene-acrylate copolymer 
(EAA), and other acrylate copolymers and the maleic acid addition products 
thereof, polypropylene (PP) and its maleic acid modified products, 
ethylene-propylene copolymer (EP) and its maleic acid modified products, 
polybutadiene resins and their anhydrous maleic acid modified products, 
styrene-butadiene-styrene block copolymer (SBS), 
styrene-ethylene-butadiene-styrene block copolymer (SEBS), fluorine type 
thermoplastic resins, polyester type thermoplastic resins, and 
compositions containing these thermoplastic resins (for example, these may 
be contained in the thermoplastic resin (A) and elastomer component (B) of 
the present invention), etc. These may be extruded by ordinary methods 
using for example a resin extruder to form sheets. 
The thickness of the bondability imparting layer is not particularly 
limited, but it is better that the thickness be smaller so as to reduce 
the tire weight and therefore 5 .mu.m to 150 .mu.m is preferable. 
The proportion of the specific thermoplastic resin (A) and elastomer 
component (B) may be suitably determined depending upon the balance 
between the thickness of the film, the resistance to air permeation, and 
the flexibility, but a preferable range is, by weight ratio, 10/90 to 
90/10, more preferably 20/80 to 85/15. 
The process of production of the polymer composition for making the air 
permeation prevention layer in the fourth aspect of the present invention 
consists of melting and kneading the thermoplastic resin and the elastomer 
(unvulcanized in case of rubber) in advance by a bi-axial kneader and 
extruder to cause the elastomer component to disperse in the thermoplastic 
resin forming the continuous phase. When vulcanizing the elastomer 
component, it is also possible to add the vulcanization agent while 
kneading and perform dynamic vulcanization of the elastomer component. 
Further, the various blending agents (except vulcanization agent) for the 
thermoplastic resin or the elastomer component may be added into the mix 
during the kneading, but it is desirable to premix them before the 
kneading. The kneader usable for kneading the thermoplastic resin and the 
elastomer is not particularly limited. A screw extruder, kneader, Bambury 
mixer, bi-axial kneader and extruder, etc. may be exemplified. Among 
these, a bi-axial kneader and extruder is preferably used for kneading of 
a resin component and rubber component and for dynamic vulcanization of a 
rubber component. Further, it is possible to use two or more types of 
kneaders and successively perform the kneading. The condition for the melt 
kneading is a temperature of at least the temperature where the 
thermoplastic resin melts. Further, a shear rate at the time of kneading 
of 2500 to 7500 sec.sup.-1 is preferable. The overall kneading time is 
from 30 seconds to 10 minutes. Further, when a vulcanization agent is 
added, the vulcanication time after the addition is preferably 15 seconds 
to 5 minutes. The polymer composition produced by the above process is 
formed into a film by extrusion or calendering by a resin extruder to form 
a film. The method of forming the film may be the method for forming a 
film from an ordinary thermoplastic resin or thermoplastic elastomer. 
The thin film thus obtained has a structure of at least part of the 
elastomer component (B) dispersed as a discontinuous phase in a matrix of 
the thermoplastic resin (A). 
By adopting this state of a dispersed structure, it becomes possible to 
impart a balance between flexibility and resistance to air permeation and 
possible to obtain the effects of an improvement of the resistance to heat 
deformation, improvement of the water resistance, etc. Further, 
thermoplastic working becomes possible. Accordingly, formation of a film 
becomes possible by ordinary plastic molding machines, that is, extrusion 
or calendering. The method of forming the film need only be a method for 
forming a film from an ordinary thermoplastic resin or thermoplastic 
elastomer. 
This bondability imparting layer may be kneaded and extruded into a film in 
the same way as the above composition. When a single composition, it may 
be formed into a film as it is by a resin extruder and may be positioned 
between the air permeation prevention layer and the layer facing at least 
one surface of the same. 
As another mode of the process of formation of the air permeation 
prevention layer and bondability imparting layer, it is possible to use 
separate resin extruders for the air permeation prevention layer 
composition and the bondability imparting layer composition, 
simultaneously extrude them, and provide a common sheeting die at the 
front ends of the two extruders to prepare multiple layer films to thereby 
obtain a prebonded double-layer film for use as a sheet for molding tires. 
Regarding the production process of a pneumatic tire having an air 
permeation prevention layer comprising a thin film of the polymer 
composition according to the present invention, as shown in FIG. 2, 
explaining the example of the case of arranging the inner liner layer 3 at 
the inside of the carcass layer 2, the polymer composition constituting 
the air permeation prevention layer of the present invention and the 
polymer or polymer composition constituting the bondability imparting 
layer are extruded to a thin film of a predetermined width and thickness, 
then this is wrapped around a tire molding drum. On top of this are then 
successively overlaid a carcass layer, a belt layer, a tread layer, and 
other members comprised of unvulcanized rubber used for the production of 
usual tires, then the drum is withdrawn. Next, this green tire is heated 
and vulcanized in accordance with an ordinary method to make a desired 
light weight pneumatic tire. Note that the same type of process may be 
followed even when providing the air permeation prevention layer on the 
outer circumference of the carcass layer. 
The material of the rubber layer for facing with the air permeation 
prevention layer according to the present invention is not particularly 
limited. Any rubber material which has been generally used as a rubber 
material for a tire in the past may be used. Examples of such a rubber are 
rubber compositions including diene rubbers such as NR, IR, BR, and SBR, 
halogenated butyl rubbers, ethylene-propylene copolymer rubbers, styrene 
elastomers, etc. to which have been added blending agents such as carbon 
black, process oil, and vulcanization agents. 
The air permeation prevention layer according to the present invention has 
an air permeation coefficient of 25.times.10.sup.-12 
cc.multidot.cm/cm.sup.2 .multidot.sec.multidot.cmHg (at 30.degree. C.) or 
less, preferably 5.times.10.sup.-12 cc.multidot.cm/cm.sup.2 
.multidot.sec.multidot.cmHg (at 30.degree. C.) or less. By making the air 
permeation coefficient 25.times.10.sup.-12 cc.multidot.cm/cm.sup.2 
.multidot.sec.multidot.cmHg (at 30.degree. C.) or less, it is possible to 
make the thickness of the air permeation prevention layer 1/2 or less of 
the thickness of the conventional air permeation prevention layer. 
On the other hand, the Young's modulus is 1 to 500 MPa, preferably 10 to 
300 MPa, and the thickness is 0.02 to 1.0 mm, preferably 0.05 to 0.5 mm. 
When the Young's modulus is less than 1 MPa, wrinkles will form at the 
time of forming the tire, whereby the handling will become difficult, 
while when more than 500 MPa, it is not possible for the film to follow 
the deformation of the tire during use. 
EXAMPLES 
The present invention will now be further illustrated by, but is by no 
means limited to, the following Examples. 
Method of Measurement of Air Permeation Coefficient of Film 
According to JIS K7126 "Test Method of Gas Permeability of Plastic Films 
and Sheets (Method A)". 
Test piece: Samples of films prepared in the Examples used. 
Test gas: Air (N.sub.2 :O.sub.2 =8:2) 
Test temperature: 30.degree. C. 
Method of Measurement of Young's Modulus of Film 
According to JIS K6251 "Tensile Test Method of Vulcanized Rubber". 
Test piece: The compositions prepared in the Examples were punched into JIS 
No. 3 dumbbell shapes in parallel to the direction of flow of the resin 
during the extrusion of the films. A tangent was drawn to the curve of the 
initial strain area of the resultant stress-strain curve and the Young's 
modulus was found from the inclination of the tangent. 
Tire Air Leakage Performance Test Method 
A 165SR13 steel radial tire (rim 13.times.41/2-J) was used, allowed to 
stand at an initial pressure of 200 kPa under no-load conditions at room 
temperature 21.degree. C. for 3 months, and measured as to pressure every 
four day interval. 
When the measured pressure is Pt, the initial pressure is Po, and the 
number of days elapsed is t, the value .alpha. is found by recurrence of 
the function: 
EQU Pt/Po=exp(-.alpha.t) 
The obtained .alpha. is used and t=30 substituted in the following formula 
to obtain .beta.: 
EQU .beta.=[1-exp(-.alpha.t)].times.100 
This value .beta. is considered the rate of reduction of pressure per month 
(%/month). 
Method of Evaluation of Melt-Fusing With Rubber 
Two mm sheets of various resins were pressed by a hot press at a pressure 
of 3 MPa for 20 minutes. The temperature at that time was made the melting 
points of the resins plus 20.degree. C. The sheets were subjected to 
peeling tests in widths of 1 inch in accordance with JIS K6256 and the 
ones where the materials were destroyed were indicated by an O mark and 
the ones where no peeling force at all was required were indicated by an X 
mark. Ones where a peeling force was required, but there was separation at 
the interface were indicated by .DELTA. marks. The rubber used at that 
time was SBR/NR of 50:50 parts with a .gamma.c of 30 mN/m. 
Tire Durability Test Method (Test Method of Durability of Inner Liner 
Layer) 
A 165SR13 steel radial tire (rim 13.times.41/2-J) was used and tested under 
conditions of an air pressure of 140 kPa and a load of 5.5 kN at room 
temperature (38.degree. C.) on a .phi.1707 mm drum at a speed of 80 km/h 
for 10,000 km, then the inner surface of the tire was inspected. The inner 
liner layer was visually inspected and those where the following trouble 
were found were judged as defective (X): 
1) Splits and cracks 
2) Peeling and blistering 
Method of Measurement of Melting Point 
Pellets of the various resins were measured by differential scan 
calorimetry (DSC) and the endothermic peaks were determined as the melting 
points. When the endothermic peaks of the melting points were unclear, the 
heat deformation temperature was measured by a thermal mechanical analysis 
(TMA) apparatus by applying a load of 1 g on a test piece of 
5.times.5.times.15 mm and this was used as a reference value for the DSC 
data. The rate of temperature rise was made 10.degree. C./min. 
Measurement of Weight of Air Permeation Prevention Layer 
Pellets were melted by a resin extruder and films of a width of 350 mm and 
a thickness of 0.05 mm were prepared and their weights measured. 
Rate of Fall of Internal Pressure 
The films of the formulations of the examples were used for inner liners 
which were attached to rims of size 13.times.41/2-J, then air leakage 
tests were run and the results used as the rate of fall of internal 
pressure inside the tires. 
Durability 
To view the effect of melt-fusion at 40 mm splices provided at the inner 
liner layer, a splice durability test was performed using a size 165SR13 
steel radial tire (rim 13.times.41/2-J) prepared under conditions of a 
vulcanization temperature of 185.degree. C. and a pressure of 2.3 MPa and 
running it under test conditions (air pressure of 140 kPa, load of 5.5 kN, 
and room temperature 38.degree. C.) on a .phi.1707 mm drum at a speed of 
80 km/h for 10,000 km. The splice portion of the tire inner liner layer 
was visually inspected and tires found to have the following problems were 
deemed defective: 
1) Openings at joins 
2) Peeling or blisters at or near joins 
Retention of Sheet Shape 
The shape retention of the sheet itself during vulcanication of the tire 
was evaluated as follows based on the stability of thickness of the inner 
liner of the tire after vulcanization. 
A liner of a thickness of 0.05 mm was laid on the surface of a carcass 
layer (carcass cord: 1500 d/2, PET count density: 50 end/50 mm width, 
thickness: 1.0 mm), this was hot pressed (2300 kPa, 185.degree. 
C..times.15 minutes), the gauge of the inner liner of the vulcanized 
sample was measured, and the stability of thickness of the inner linerr 
was found from the maximum value (Tmax) and minimum value (Tmin) by the 
following formula: 
EQU [(Tmax-Tmin)/((Tmax+Tmin)/2)] 
The value is preferably not more than 0.2. 
Note that stability of thickness of the inner liner is essential from the 
following viewpoints: 
1) If nonuniform, air would easily leak from the thin portions, and 
therefore, the resistance to air leakage would become poor. 
2) Unevenness of the tire vulcanization bladder or carcass cord would cause 
unevenness if the fluidity of the liner material were high at the time of 
vulcanization. 
3) If there is a large variation in the liner gauge, the resistance to air 
leakage could be maintained by increasing the initial thickness by that 
amount, but there would be no meaning to increasing the gauge over 20% 
from the standpoint of costs and the desired reduction of weight. 
Examples I 
The brands and basic physical properties of the polymers used in the 
Examples and Comparative Examples listed below are shown in Table I-1. 
Here, regarding the basic physical properties of the rubbers in the 
elastomer components, there are materials which cannot retain any shape in 
their original form alone and therefore are difficult to measure, so the 
values of the formulations of Table I-2 which have been vulcanized are 
used as typical properties. Futher, the brands of the blending agents are 
shown in Table I-3. 
TABLE I-1 
__________________________________________________________________________ 
Air permeation 
Young'sient 
Component 
Material Tradename Manufacturer (.times. 10.sup.-12 cc 
.multidot. cm/cm.sup.2 
.multidot. s .multidot. 
modulus 
__________________________________________________________________________ 
(MPa) 
Component A 
N11 Rirusan BESNO TL 
Atochem 11.0 560 
N6 CM 4061 Toray 0.42 795 
EVOH Eval EPE153B 
Kuraray 0.052 1020 
MXD6 Reny 6002 Mitsubishi Gas Chemical 
0.019 1550 
PBT Ultradur B4550 
BASF 0.82 2650 
AS Sevian 500 Daicel Chemical Industries 
6.71 2600 
Cellulose acetate 
Aceti 10 Daicel Chemical Industries 
0.16 2800 
PVDF KF Polymer 1000 
Kureha Chemical Industry 
1.16 1100 
PI New-TP1450 Mitsui Toatsu 0.015 3000 
N6/66 Ultramid C35 
BASF 0.51 1000 
Component B 
SBR Nipol 1502 Nippon Zeon 3100 4.2 
M-EPM Tafmer MP0610 
Mitsui Petrochemical Industries 
2900 7.2 
Br-IIR Exxon Bromobutyl 2244 
Exxon Chemical 
55 10.5 
Br-IPMS EXXPRO90-10 
Exxon Chemical 
50 12.0 
Polyester elastomer 
Hytrel 5577 
Toray-Dupont 38.0 450.0 
Polyamide elastomer 
PEBAX4033 Atochem 3710.0 78.0 
CHR HERCLOR C Hercules 30.0 5.5 
NBR Nipol 1043 Nippon Zeon 110.0 8.3 
CM ELASLEN 301A 
Showa Denko 36.0 8.0 
M-CM ELASLEN Super G107 
Showa Denko 42.0 7.7 
Component C 
PC Novarex 7022A 
Mitsubishi Chemical 
76.1 2460 
__________________________________________________________________________ 
TABLE I-2 
______________________________________ 
Vulcanization Systems of Various Elastomers 
A B C D E F G H 
______________________________________ 
SBR 100 -- -- -- -- -- -- -- 
Br-IIR -- 100 -- -- -- -- -- -- 
NBR -- -- 100 -- -- -- -- -- 
Br-IPMS -- -- -- 100 -- -- -- -- 
CHR -- -- -- -- 100 -- -- -- 
CM -- -- -- -- -- 100 -- -- 
M-CM -- -- -- -- -- -- 100 -- 
M-EPM -- -- -- -- -- -- -- 100 
HAF 30 30 30 30 30 30 30 30 
ZnO 3 3 3 1 -- -- -- -- 
Sulfur 2 2 2 -- -- -- -- -- 
Trimercapto- 
-- -- -- -- 1.5 1.5 1.5 -- 
triazine 
Methylene 
-- -- -- -- -- -- -- 0.6 
dianiline 
DM 1 1 1 -- -- -- -- -- 
MDCA -- -- -- -- 1.5 1.5 1.5 -- 
Stearic acid 
1 1 1 1 -- -- -- -- 
Zinc stearate 
-- -- -- 2 -- -- -- -- 
______________________________________ 
TABLE I-3 
__________________________________________________________________________ 
Brands of Various Blending Agents 
Material Tradename Manufacturer 
__________________________________________________________________________ 
ZnO Zinc White No. 3 Seido Chemical Industry 
MgO Kyowa Mag 150 Kyowa Kagaku 
Sulfur Powdered sulfur Karuizawa Seirensho 
Trimercapto triazine 
ZISNET-F Sankyo Chemical 
Methylene dianiline 
Sumicure-M Sumitomo Chemical 
DM Nocceler-DM Ouchi Shinko Chemical Industrial 
TT Nocceler-TT Ouchi Shinko Chemical Industrial 
CZ Nocceler-CZ Ouchi Shinko Chemical Industrial 
MDCA 2-mercaptobenzothiazole dicyclohexyl amine 
Ouchi Shinko Chemical Industrial 
Zinc stearate Zinc stearate Seido Chemical Industry 
Stearic acid Bis-stearyl acid NY Nippon Yushi 
Petroleum based hydrocarbon resin 
ESCOREZ 1102 Esso 
Paraffinic process oil 
Machine Oil 22 Showa Shell Sekiyu 
GPF Seast V Tokai Carbon 
HAF Seast N Tokai Carbon 
Caprolactam E-aminocaprolactam Ube Industries 
__________________________________________________________________________ 
Examples I-1 to I-8 
One or two types of the various thermoplastic resin components (A), the 
elastomer components (B), and, in some cases, vulcanization agents, 
lubricants, or other components were kneaded in the various formulations 
(parts by weight) shown in Table I-4 to Table I-11 by a bi-axial kneader, 
pelletized, then formed into films of a width of 350 mm and a thickness of 
0.1 mm by an extruder. 
The air permeation coefficient and Young's modulus of the resultant films 
were measured. The results are shown in Table I-4 to Table I-11. 
TABLE I-4 
__________________________________________________________________________ 
Example I-1 
Formulation no. 
1 2* 3* 4* 5 6 7* 8* 9* 10 11 12* 
13* 
14* 
15 16* 
17* 
18* 
__________________________________________________________________________ 
N6 90 80 50 20 10 -- -- -- -- -- -- -- -- -- 34 32 20 4 
EVOH -- -- -- -- -- 90 80 50 20 10 -- -- -- -- -- -- -- -- 
MXD6 -- -- -- -- -- -- -- -- -- -- 80 75 50 10 51 48 30 6 
Br-IPMS 10 20 50 80 90 10 20 50 80 90 20 25 50 90 15 20 50 90 
Air permeation 
0.67 
1.09 
4.58 
19.22 
31.00 
0.11 
0.23 
1.73 
13.03 
25.52 
0.06 
0.08 
0.71 
21.33 
0.13 
0.18 
1.49 
24.92 
coefficient (.times. 10.sup.-12 
cc .multidot. cm/cm.sup.2 .multidot. s .multidot. 
cmHg) (at 30.degree. C.) 
Young's modulus 
523 
344 
98 28 18 654 
419 
111 
29 19 586 
460 
136 
20 596 
473 
119 
19 
(MPa) 
__________________________________________________________________________ 
*Examples of invention 
TABLE I-5 
__________________________________________________________________________ 
Example I-2 
Formulation no. 
1 2* 3* 4 5 6* 7* 8 9 10* 
11* 12 13 14* 
15* 
16 
__________________________________________________________________________ 
N6 90 85 75 50 -- -- -- -- -- -- -- -- 34 32 20 10 
EVOH -- -- -- -- 90 80 50 25 -- -- -- -- -- -- -- -- 
MXD6 -- -- -- -- -- -- -- -- 80 75 50 25 51 48 30 15 
M-EPM 10 15 25 50 10 20 50 75 20 25 50 75 15 20 50 75 
Air permeation coefficient 
1.02 
1.60 
3.89 
36.08 
0.18 
0.53 
13.64 
205.6 
0.13 
0.24 
5.57 
131.4 
0.24 
0.42 
11.80 
191.0 
(.times. 10.sup.-12 
cc .multidot. cm/cm.sup.2 .multidot. s .multidot. cmHg) (at 
30.degree. C.) 
Young's modulus (MPa) 
505 
393 
24S 76 622 
379 
86 25 529 
405 
106 28 552 
428 
92 26 
__________________________________________________________________________ 
*Examples of invention 
TABLE I-6 
__________________________________________________________________________ 
Example I-3 
Formulation no. 
1 2* 3* 4 5 6* 7* 8 9 10* 11* 12 
__________________________________________________________________________ 
N6 95 90 60 50 20 15 10 5 90 80 60 50 
SBR 5 10 40 50 -- -- -- -- -- -- -- -- 
Polyester elastomer 
-- -- -- -- 80 85 90 95 -- -- -- -- 
Polyamide elastomer 
-- -- -- -- -- -- -- -- 10 20 40 50 
Air permeation coefficient 
0.58 
1.05 
2.88 
36.53 
15.51 
19.41 
24.28 
30.38 
1.06 
2.63 
16.13 
39.92 
(.times. 10.sup.-12 cc .multidot. cm/cm.sup.2 .multidot. s .multidot. 
cmHg) 
(at 30.degree. C.) 
Young's modulus (MPa) 
521 471 98 58 505 490 477 463 630 500 314 249 
__________________________________________________________________________ 
*Examples of invention 
TABLE I-7 
__________________________________________________________________________ 
Example I-4 
__________________________________________________________________________ 
Formulation no. 
1 2* 3* 4* 5* 6 7 8* 9* 10 
__________________________________________________________________________ 
PBT 20 30 45 45 60 70 -- -- -- -- 
AS -- -- -- -- -- -- 30 40 60 70 
Cellulose acetate 
-- -- -- -- -- -- -- -- -- -- 
PVDF -- -- -- -- -- -- -- -- -- -- 
Aromatic polyimide 
-- -- -- -- -- -- -- -- -- -- 
Br-IPMS 80 70 55 55 40 30 70 60 40 30 
ZnO 0.40 
0.35 
0.28 -- 0.20 0.15 
-- -- -- -- 
Stearic acid 1.60 
1.40 
1.10 -- 0.80 0.60 
-- -- -- -- 
Zinc stearate 0.80 
0.70 
0.55 -- 0.40 0.30 
-- -- -- -- 
Air permeation coefficient 
25.09 
14.61 
7.86 7.87 
4.24 2.81 
27.42 
22.41 
15.03 
12.33 
(.times. 10.sup.-12 cc .multidot. cm/cm.sup.2 .multidot. s .multidot. 
cmHg) 
(at 30.degree. C.) 
Young's modulus (MPa) 
32 55 123 136 275 501 60 103 302 518 
__________________________________________________________________________ 
Formulation no. 
11 12* 
13* 14 15 16* 
17* 18 19 20* 
21* 22 
__________________________________________________________________________ 
PBT -- -- -- -- -- -- -- -- -- -- -- -- 
AS -- -- -- -- -- -- -- -- -- -- -- -- 
Cellulose acetate 
10 20 60 70 -- -- -- -- -- -- -- -- 
PVDF -- -- -- -- 20 30 80 90 -- -- -- -- 
Aromatic polyimide 
-- -- -- -- -- -- -- -- 10 20 60 70 
Br-IPMS 90 80 40 30 80 70 20 10 90 80 40 30 
ZnO -- -- -- -- -- -- -- -- -- -- -- -- 
Stearic acid -- -- -- -- -- -- -- -- -- -- -- -- 
Zinc stearate -- -- -- -- -- -- -- -- -- -- -- -- 
Air permeation coefficient 
28.22 
15.83 
1.59 
0.90 
26.89 
16.22 
2.46 
1.69 
25.79 
9.87 
0.39 
0.17 
(.times. 10.sup.-12 cc .multidot. cm/cm.sup.2 .multidot. s .multidot. 
cmHg) 
(at 30.degree. C.) 
Young's modulus (MPa) 
21 36 316 545 30 47 446 700 21 36 330 572 
__________________________________________________________________________ 
*Examples of invention 
TABLE I-8 
__________________________________________________________________________ 
Example I-5 
__________________________________________________________________________ 
Formulation no. 
1* 2* 3* 4* 5* 6* 7* 8* 9* 10* 
__________________________________________________________________________ 
N6 70 50 70 50 -- -- -- -- -- -- 
MXD6 -- -- -- -- -- -- 70 50 70 50 
EVOH -- -- -- -- 70 50 -- -- -- -- 
Br-IPMS 30 50 30 50 30 50 30 50 30 50 
M-EPM -- -- -- -- -- -- -- -- -- -- 
ZnO -- -- 0.15 
0.25 
0.15 
0.25 
-- -- 0.15 
0.25 
Stearic acid -- -- 0.60 
1.00 
0.60 
1.00 
-- -- 0.60 
1.00 
Zinc stearate -- -- 0.30 
0.50 
0.30 
0.50 
-- -- 0.30 
0.50 
Methylene dianiline 
-- -- -- -- -- -- -- -- -- -- 
Air permeation coefficient 
1.76 
4.58 
1.76 
4.58 
0.45 
1.73 
0.13 
0.71 
0.13 
0.71 
(.times. 10.sup.-12 cc .multidot. cm/cm.sup.2 .multidot. s .multidot. 
cmHg) 
(at 30.degree. C.) 
Young's modulus (MPa) 
226 98 203 88 242 100 361 136 325 123 
__________________________________________________________________________ 
Formulation no. 
11* 12* 13* 14* 15* 16* 17* 18* 19* 
__________________________________________________________________________ 
N6 28 20 28 20 70 70 -- -- 28 
MXD6 42 30 42 30 -- -- -- 70 42 
EVOH -- -- -- -- -- -- 70 -- -- 
Br-IPMS 30 50 30 50 -- -- -- -- -- 
M-EPM -- -- -- -- 30 30 30 30 30 
ZnO -- -- 0.15 0.25 
-- -- -- -- -- 
Stearic acid -- -- 0.60 1.00 
-- -- -- -- -- 
Zinc stearate -- -- 0.30 0.50 
-- -- -- -- -- 
Methylene dianiline 
-- -- -- -- -- 0.18 0.18 
0.18 
0.18 
Air permeation coefficient 
0.37 
1.49 
0.37 1.49 
6.08 
6.08 1.56 
0.44 
2.13 
(.times. 10.sup.-12 cc .multidot. cm/cm.sup.2 .multidot. s .multidot. 
cmHg) 
(at 30.degree. C.) 
Young's modulus (MPa) 
299 119 269 107 194 174 208 278 257 
__________________________________________________________________________ 
*Examples of invention 
TABLE I-9 
__________________________________________________________________________ 
Example I-6 
Formulation no. 
1* 2* 3* 4* 5* 6* 7 8* 9* 10* 
11* 
12* 
__________________________________________________________________________ 
N6 90 50 50 20 20 10 36 32 20 20 4 4 
MXD6 -- -- -- -- -- -- 54 48 30 30 6 6 
CHR 10 50 50 80 80 90 10 20 50 50 90 90 
MgO 0.50 
2.50 
-- 4.00 
-- 4.50 
0.50 
1.00 
2.50 
-- 4.50 
-- 
Stearic acid 0.20 
1.00 
-- 1.60 
-- 1.80 
0.20 
0.40 
1.00 
-- 1.80 
-- 
TT 0.10 
0.50 
-- 0.50 
-- 0.90 
0.10 
0.20 
0.50 
-- 0.90 
-- 
Air permeation coefficient 
0.66 
3.59 
3.57 
12.80 
12.60 
19.61 
0.04 
0.07 
0.71 
0.70 
14.21 
14.19 
(.times. 10.sup.-12 cc .multidot. cm/cm.sup.2 .multidot. s .multidot. 
cmHg) 
(at 30.degree. C.) 
Young's modulus (MPa) 
483 66 60 15 13 9 693 405 81 73 9 8 
__________________________________________________________________________ 
*Examples of invention 
TABLE I-10 
__________________________________________________________________________ 
Example I-7 
Formulation no. 
1 2* 3* 4* 5 6 7* 8* 9 10* 
11* 
__________________________________________________________________________ 
N6 90 80 50 30 20 -- -- -- -- -- -- 
MXD6 -- -- -- -- -- 80 30 10 80 30 10 
NBR 10 20 50 70 80 -- -- -- -- -- -- 
CM -- -- -- -- -- 20 70 90 -- -- -- 
M-CM -- -- -- -- -- -- -- -- 20 70 90 
Sulfur 0.10 
0.20 
0.50 
0.70 
0.80 
-- -- -- -- -- -- 
TT 0.10 
0.20 
0.50 
0.70 
0.80 
-- -- -- -- -- -- 
CZ 0.10 
0.20 
0.50 
0.70 
0.80 
-- -- -- -- -- -- 
Trimercapto triazine 
-- -- -- -- -- 0.30 
1.05 
1.35 
0.30 
1.05 
1.35 
MDCA -- -- -- -- -- 0.30 
1.05 
1.35 
0.30 
1.05 
1.35 
Air permeation coefficient 
0.75 
1.30 
6.88 
20.84 
36.28 
0.05 
3.09 
15.91 
0.05 
3.44 
18.22 
(.times. 10.sup.-12 cc .multidot. cm/cm.sup.2 .multidot. s .multidot. 
cmHg) 
(at 30.degree. C.) 
Young's modulus (MPa) 
504 319 81 33 21 541 39 14 536 38 13 
__________________________________________________________________________ 
*Examples of invention 
TABLE I-11 
__________________________________________________________________________ 
Example I-8 
Formulation no. 
1* 2* 3* 4* 5* 6* 7* 
__________________________________________________________________________ 
MXD6 -- -- -- -- -- -- 63 
N6 63 -- -- -- -- 63 -- 
N6/66 -- 59 56 61 60 -- -- 
N11 19 19 19 19 20 17 17 
M-EPM 18 22 25 20 20 18 18 
Caprolactum -- -- -- -- -- 2 2 
Air permeation coefficient 
3.94 
6.21 
8.07 
5.22 
5.38 
6.52 
0.61 
(.times.10.sup.-12 cc .multidot. cm/cm.sup.2 .multidot. s .multidot. 
cmHg) 
(at 30.degree. C.) 
Young's modulus (MPa) 
319 303 261 334 332 281 428 
__________________________________________________________________________ 
*Examples of invention 
Example I-9 
The various thermoplastic resin components (A), the elastomer components 
(B), a third component (polycarbonate), and, in some cases, vulcanization 
agents, lubricants, or other components were kneaded in the various 
formulations (parts by weight) shown in Table I-12 by a bi-axial kneader, 
pelletized, then formed into films of a width of 350 mm and a thickness of 
0.2 mm by an extruder. 
The air permeation coefficient and Young's modulus of the resultant films 
were measured. The results are shown in Table I-12. 
TABLE I-12 
__________________________________________________________________________ 
Example I-9 
Formulation no. 
1* 2* 3* 4* 5 6* 7* 8* 9 10* 
11* 12* 13* 14* 
__________________________________________________________________________ 
MXD6 27 21 21 15 12 36 28 20 16 -- -- -- -- -- 
EVOH -- -- -- -- -- -- -- -- -- 27 21 21 15 12 
Br-IPMS 63 49 49 35 28 -- -- -- -- 63 49 49 35 28 
CHR -- -- -- -- -- 54 42 30 24 -- -- -- -- -- 
PC 10 30 30 50 60 10 30 50 60 10 30 30 50 60 
ZnO 0.32 
0.25 
-- 0.18 
0.14 
-- -- -- -- 0.32 
0.25 
-- 0.18 
0.14 
Stearic acid 
1.26 
1.12 
-- 0.70 
0.56 
1.08 
0.84 
0.60 
0.48 
1.26 
0.98 
-- 0.70 
0.56 
Zinc stearate 
0.63 
0.49 
-- 0.35 
0.28 
-- -- -- -- 0.63 
0.49 
-- 0.35 
0.28 
MgO -- -- -- -- -- 2.70 
2.10 
1.50 
1.20 
-- -- -- -- -- 
TT -- -- -- -- -- 0.54 
0.42 
0.30 
0.24 
-- -- -- -- -- 
Air permeation 
6.22 
10.90 
10.85 
18.93 
25.00 
2.32 
5.04 
11.01 
16.11 
8.48 
13.81 
13.76 
22.51 
28.76 
coefficient 
(.times.10.sup.-12 cc .multidot. cm/ 
cm.sup.2 .multidot. s .multidot. cmHg) 
at 30.degree. C.) 
Young's modulus 
76 164 148 356 524 77 167 359 528 68 151 136 335 505 
(MPa) 
__________________________________________________________________________ 
*Examples of invention 
Examples I-10 to I-13 and Comparative Example I-1 
Various blending agents were mixed into Br-IIR and Br-IPMS to prepare the 
master batches A and B in a closed Bambury mixer. The formulations of the 
master batches are shown in Table I-13: 
TABLE I-13 
______________________________________ 
Formulation of Master Batches 
Master 
Master 
batch A 
batch B 
______________________________________ 
Br-IIR 100 -- 
Br-IPMS -- 100 
GPF 60 60 
Stearic acid 1 -- 
Petroleum based hydrocarbon 
10 -- 
resin 
Paraffinic process oil 
10 20 
______________________________________ 
These master batches were pelletized using a rubber pelletizer, kneaded 
with resin materials and cross-linking agents by a bi-axial kneader by the 
various formulations (parts by weight) shown in Table I-14, pelletized, 
then extruded by an extruder to prepare films of a width of 350 mm and a 
thickness of 0.1 mm. The air permeation coefficient and Young's modulus of 
the resultant films were measured. Further, these films were wrapped 
around tire molding drums, then overlaid with carcasses, sidewalls, 
treads, and other tire members and inflated to obtain green tires. The 
green tires were vulcanized by a vulcanizer at 180.degree. C. for 10 
minutes to finish them into tires of tire size 165SR13. 
On the other hand, as a Comparative Example, a green tire was formed having 
an inner liner layer of about 0.5 mm, comprised of an unvulcanized butyl 
rubber, on the inner surface of the green tire through tie rubber of a 
thickness of about 0.7 mm. This was then vulcanized to finish the tire 
(size 165SR13). The formulation of the inner liner layer, the air 
permeation coefficient, and the Young's modulus are shown in Table I-14 in 
the same way as with the examples. The weights of the inner liners of the 
pneumatic tires obtained were measured and air leakage tests performed. 
The results are shown in Table I-14. 
TABLE I-14 
__________________________________________________________________________ 
Examples I-10 to I-13 and Comparative Example I-1 
Ex. I-10 
Ex. I-11 
Ex. I-12 
Ex. I-13 
Comp. Ex. I-1 
__________________________________________________________________________ 
N6 50 -- 50 -- -- 
MXD6 -- 50 -- 50 -- 
Master batch A 
90.5 90.5 
-- -- 181 
Master batch B 
-- -- 90 90 -- 
ZnO 1.5 1.5 0.25 
0.25 
30 
DM 0.5 0.5 -- -- 1 
Sulfur 0.3 0.3 -- -- 0.6 
Stearic acid -- -- 1 1 -- 
Zinc stearate -- -- 0.5 0.5 -- 
Air permeation coefficient 
4.33 1.02 
4.13 
0.98 
58.2 
(.times.10.sup.-12 cc .multidot. cm/cm.sup.2 .multidot. s .multidot. 
cmHg) 
(at 30.degree. C.) 
Young's modulus (MPa) 
91 128 93 130 12.2 
Rate of fall of internal pressure 
1.5 0.4 1.4 0.4 2.7 
Inner liner weight (g) 
100 100 100 100 650 
__________________________________________________________________________ 
Example I-14 
Using the eight types of bromine-modified polyisoprene-p-methylmethylene 
copolymer rubbers shown in Table I-15, the air permeation coefficient and 
Young's modulus were evaluated in the same way as shown in the previous 
examples using as the thermoplastic resin components N11 (Rirusan BESNO 
TL) (see Table I-1), N6/N66 (Ultramide C35) (see Table I-1), and EVOH 
(Eval EPE153B) (see Table I-1) and using the formulations of polymers 
shown in Table I-16, Table I-17, and Table I-18. The results are shown in 
Table I-14 to Table I-18. Note that the rubber formulation of the modified 
polyisobutylene rubber was as follows: 
______________________________________ 
Rubber Formulation 
______________________________________ 
Modified polyisobutylene rubber 
100 parts by weight 
Zinc stearate 1 part by weight 
Stearic acid 2 parts by weight 
Zinc White No. 3 0.5 part by weight 
______________________________________ 
TABLE I-15 
______________________________________ 
Modified Polyisobutylene Rubber Compositions 
Mooney 
viscosity 
PMS*.sup.1 
Bromine ML.sub.1+8 
(wt %) (wt %) (120.degree. C.) 
______________________________________ 
Modified polyisobutylene 
7.5 2 38 
rubber 1 
Modified polyisobutylene 
7.5 2 45 
rubber 2 
Modified polyisobutylene 
5 1.2 35 
rubber 3*.sup.2 
Modified polyisobutylene 
5 1.2 45 
rubber 4*.sup.2 
Modified polyisobutylene 
5 0.8 45 
rubber 5*.sup.2 
Modified polyisobutylene 
7.5 2 28 
rubber 6*.sup.2 
Modified polyisobutylene 
7.5 0.8 45 
rubber 7*.sup.2 
Modified polyisobutylene 
20 1.2 45 
rubber 8 
______________________________________ 
*.sup.1 PMS: pmethylstyrene 
*.sup.2 Rubber out of scope of present invention 
TABLE I-16 
__________________________________________________________________________ 
1 2 3 (Comp. 
4 (Comp. 
5 (Comp. 
(Ex.) 
(Ex.) 
Ex.) Ex.) Ex.) 6 (Comp. Ex.) 
7 (Comp. Ex.) 
8 (Ex.) 
__________________________________________________________________________ 
Modified polyisobutylene rubber 1 
50 -- -- -- -- -- -- -- 
Modified polyisobutylene rubber 2 
-- 50 -- -- -- -- -- -- 
Modified polyisobutylene rubber 3 
-- -- 50 -- -- -- -- -- 
Modified polyisobutylene rubber 4 
-- -- -- 50 -- -- -- -- 
Modified polyisobutylene rubber 5 
-- -- -- -- 50 -- -- -- 
Modified polyisobutylene rubber 6 
-- -- -- -- -- 50 -- -- 
Modified polyisobutylene rubber 7 
-- -- -- -- -- -- 50 -- 
Modified polyisobutylene rubber 8 
-- -- -- -- -- -- -- 50 
N11 50 50 50 50 50 50 50 50 
Air permeation coefficient 
1.62 
1.27 
3.17 2.57 2.32 2.22 1.32 0.82 
(.times.10.sup.-11 cc .multidot. cm/cm.sup.2 .multidot. s .multidot. 
cmHg) 
(at 30.degree. C.) 
Young's modulus (MPa) 
146.1 
146.0 
145.8 
145.8 
145.8 
146.0 145.8 145.9 
TB (MPa) 30.2 
30.1 
30.1 30.2 30.1 30.0 27.6 30.4 
__________________________________________________________________________ 
TABLE I-17 
__________________________________________________________________________ 
9 11 (Comp. 
12 (Comp. 
13 (Comp. 
(Ex.) 
10 (Ex.) 
Ex.) Ex.) Ex.) 14 (Comp. Ex.) 
15 (Comp. Ex.) 
16 (Ex.) 
__________________________________________________________________________ 
Modified polyisobutylene rubber 1 
50 -- -- -- -- -- -- -- 
Modified polyisobutylene rubber 2 
-- 50 -- -- -- -- -- -- 
Modified polyisobutylene rubber 3 
-- -- 50 -- -- -- -- -- 
Modified polyisobutylene rubber 4 
-- -- -- 50 -- -- -- -- 
Modified polyisobutylene rubber 5 
-- -- -- -- 50 -- -- -- 
Modified polyisobutylene rubber 6 
-- -- -- -- -- 50 -- -- 
Modified polyisobutylene rubber 7 
-- -- -- -- -- -- 50 -- 
Modified polyisobutylene rubber 8 
-- -- -- -- -- -- -- 50 
N6/66 50 50 50 50 50 50 50 50 
Air permeation coefficient 
1.44 
1.09 
2.99 2.39 2.14 2.04 1.14 0.64 
(.times.10.sup.-11 cc .multidot. cm/cm.sup.2 .multidot. s .multidot. 
cmHg) 
(at 30.degree. C.) 
Young's modulus (MPa) 
86.6 
86.5 
86.3 86.3 86.3 86.5 86.3 86.4 
TB (MPa) 41.2 
40.9 
41.0 41.1 41.1 41.0 38.6 41.4 
__________________________________________________________________________ 
TABLE I-18 
__________________________________________________________________________ 
19 (Comp. 
20 (Comp. 
21 (Comp. 
17 (Ex.) 
18 (Ex.) 
Ex.) Ex.) Ex.) 22 (Comp. Ex.) 
23 (Comp. Ex.) 
24 (Ex.) 
__________________________________________________________________________ 
Modified polyisobutylene rubber 1 
50 -- -- -- -- -- -- -- 
Modified polyisobutylene rubber 2 
-- 50 -- -- -- -- -- -- 
Modified polyisobutylene rubber 3 
-- -- 50 -- -- -- -- -- 
Modified polyisobutylene rubber 4 
-- -- -- 50 -- -- -- -- 
Modified polyisobutylene rubber 5 
-- -- -- -- 50 -- -- -- 
Modified polyisobutylene rubber 6 
-- -- -- -- -- 50 -- -- 
Modified polyisobutylene rubber 7 
-- -- -- -- -- -- 50 -- 
Modified polyisobutylene rubber 8 
-- -- -- -- -- -- -- 50 
EVOH 50 50 50 50 50 50 50 50 
Air permeation coefficient 
1.35 
1.00 
2.90 2.30 2.05 1.95 1.05 0.55 
(.times.10.sup.-11 cc .multidot. cm/cm.sup.2 .multidot. s .multidot. 
cmHg) 
(at 30.degree. C.) 
Young's modulus (MPa) 
478.6 
478.5 
478.3 
478.3 
478.3 
478.5 478.3 478.4 
TB (MPa) 36.2 
36.0 
36.2 36.0 36.1 36.0 33.2 36.4 
__________________________________________________________________________ 
As explained above, according to the first aspect of the present invention, 
it is possible to obtain a tire polymer composition which is suitable for 
an air permeation prevention layer for a pneumatic tire which enables 
maintenance of the retention of air pressure in the tire well, maintenance 
of the flexibility, and lightening of the weight of the tire. 
Examples II-1 to II-14 
One or two types of the various thermoplastic resin components (A) and (C), 
the elastomer components (B), and, in some cases, vulcanization agents, 
lubricants, or other components were kneaded in the various formulations 
(parts by weight) shown in Table II-1 to Table II-14 by a bi-axial 
kneader, then continuously pelletized by a resin pelletizer, then the 
pellets used to form films of a width of 350 mm and a thickness of 0.1 mm 
by a resin extruder. 
The air permeation coefficient and Young's modulus of the resultant films 
were measured. The results are shown in Table II-1 to II-14. 
TABLE II-1 
__________________________________________________________________________ 
(Example II-1) 
Comp- 
onent 
Formulation No. 
1 2*.sup.1 
3*.sup.1 
4*.sup.1 
5*.sup.1 
6*.sup.1 
7*.sup.1 
8*.sup.1 
9*.sup.1 
10 11 12 
__________________________________________________________________________ 
(A) N6*.sup.2 28.0 
26.6 
25.2 
22.4 
19.6 
16.8 
14.0 
11.2 
8.4 5.6 2.8 -- 
MXD6*.sup.3 
42.0 
39.9 
37.8 
33.6 
29.4 
25.2 
21.0 
16.8 
12.6 
8.4 4.2 -- 
(B) Br-poly(isoprene-p- 
30.0 
28#5 
27.0 
24.0 
21.0 
18.0 
15.0 
12.0 
9.0 6.0 3.0 -- 
methylstyrene) 
(C) UHMWPE*.sup.4 (.DELTA..gamma.c = 1) 
0 5 10 20 30 40 50 60 70 80 90 100 
Mea- 
Air permeation coeffi- 
0.48 
0.60 
0.75 
1.18 
1.86 
2.93 
4.60 
7.22 
11.34 
17.82 
28.00 
44.00 
sure- 
cient (.times.10.sup.-12 cc .multidot. cm/ 
ment 
cm.sup.2 .multidot. s .multidot. cmHg) 
items 
(at 30.degree. C.) 
Young's modulus (MPa) 
299 310 321 344 369 305 424 454 487 522 560 600 
Melt-fusion with rubber 
x .DELTA. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
__________________________________________________________________________ 
*.sup.1 Example of invention 
*.sup.2 CM4061 (Toray, 6nylon) 
*.sup.3 Reny 6002 (Mitsubishi Gas Chemical, copolymer nylon) 
*.sup.4 Hizexmillion (240M) (Mitsui Petrochemical Industries) 
TABLE II-2 
__________________________________________________________________________ 
(Example II-2) 
Comp- 
onent 
Formulation No. 
1 2*.sup.1 
3*.sup.1 
4*.sup.1 
5*.sup.1 
6*.sup.1 
7*.sup.1 
8*.sup.1 
9*.sup.1 
10 11 12 
__________________________________________________________________________ 
(A) N6*.sup.2 28.0 
26.6 
25.2 
22.4 
19.6 
16.8 
14.0 
11.2 
8.4 5.6 2.8 -- 
MXD6*.sup.3 
42.0 
39.9 
37.8 
33.6 
29.4 
25.2 
21.0 
16.8 
12.6 
8.4 4.2 -- 
(B) Br-poly(isoprene-p- 
30.0 
28.5 
27.0 
24.0 
21.0 
18.0 
15.0 
12.0 
9.0 6.0 3.0 -- 
methylstyrene) 
(C) EEA*.sup.4 (.DELTA..gamma.c = 3) 
0 5 10 20 30 40 50 60 70 80 90 100 
Mea- 
Air permeation 
0.48 
0.63 
0.52 
1.40 
2.35 
4.06 
6.93 
11.82 
20.16 
34.35 
58.63 
100.00 
sure- 
coefficient 
ment 
(.times.10.sup.-12 cc .multidot. cm/cm.sup.2 .multidot. 
items 
s .multidot. cmHg) (at 30.degree. C.) 
Young's modulus (MPa) 
299 275 252 213 180 152 128 108 91 77 65 55 
Melt-fusion with rubber 
x .DELTA. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
__________________________________________________________________________ 
*.sup.1 Example of invention 
*.sup.2 CM4061 (Toray, 6nylon) 
*.sup.3 Reny 6002 (Mitsubishi Gas Chemical, copolymer nylon) 
*.sup.4 NUC6070 (Unitika, ethyleneethylacrylate copolymer) 
TABLE II-3 
__________________________________________________________________________ 
(Example II-3) 
Comp- 
onent 
Formulation No. 
1 2*.sup.1 
3*.sup.1 
4*.sup.1 
5*.sup.1 
6*.sup.1 
7*.sup.1 
8*.sup.1 
9*.sup.1 
10 11 12 
__________________________________________________________________________ 
(A) EVOH*.sup.2 
70.0 
66.5 
63.0 
56.0 
49.0 
42.0 
35.0 
28.0 
21.0 
14.0 
7.0 -- 
(B) Br-poly(isoprene-p- 
30.0 
28.5 
27.0 
24.0 
21.0 
18.0 
15.0 
12.0 
9.0 6.0 3.0 -- 
methylstyrene) 
(C) UHMWPE*.sup.3 (.DELTA..gamma.c = 1) 
0 5 10 20 30 40 50 60 70 80 90 100 
Mea- 
Air permeation 
0.41 
0.52 
0.65 
1.04 
1.66 
2.65 
4.24 
6.77 
10.81 
17.26 
27.55 
44.00 
sure- 
coefficient 
ment 
(.times.10.sup.-12 cc .multidot. cm/cm.sup.2 .multidot. 
items 
s .multidot. cmHg) (at 30.degree. C.) 
Young's modulus (MPa) 
269 280 291 316 342 371 402 435 472 511 554 600 
Melt-fusion with rubber 
x .DELTA. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
__________________________________________________________________________ 
*.sup.1 Example of invention 
*.sup.2 Eval EPE153B (Kuraray) 
*.sup.3 Hizexmillion (240M) (Mitsui Petrochemical Industries) 
TABLE II-4 
__________________________________________________________________________ 
(Example II-4) 
Comp- 
onent 
Formulation No. 
1 2*.sup.1 
3*.sup.1 
4*.sup.1 
5*.sup.1 
6*.sup.1 
7*.sup.1 
8*.sup.1 
9*.sup.1 
10 11 12 
__________________________________________________________________________ 
(A) EVOH*.sup.2 
70.0 
66.5 
63.0 
56.0 
49.0 
42.0 
35.0 
28.0 
21.0 
14.0 
7.0 -- 
(B) Br-poly(isoprene-p- 
30.0 
28.5 
27.0 
24.0 
21.0 
18.0 
15.0 
12.0 
9.0 6.0 3.0 -- 
methylstyrene) 
(C) EEA*.sup.3 (.DELTA..gamma.c = 1) 
0 5 10 20 30 40 50 60 70 80 90 100 
Mea- 
Air permeation 
0.41 
0.54 
0.71 
1.23 
2.13 
3.69 
6.39 
11.08 
19.20 
33.28 
57.69 
100.00 
sure- 
coefficient 
ment 
(.times.10.sup.-12 cc .multidot. cm/cm.sup.2 .multidot. 
items 
s .multidot. cmHg) (at 30.degree. C.) 
Young's modulus (MPa) 
269 248 230 196 167 143 122 104 89 76 64 55 
Melt-fusion with rubber 
x .DELTA. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
__________________________________________________________________________ 
*.sup.1 Example of invention 
*.sup.2 Eval EPE153B (Kuraray) 
*.sup.3 Hizexmillion (240M) (Mitsui Petrochemical Industries) 
TABLE II-5 
__________________________________________________________________________ 
(Example II-5) 
Comp- 
onent 
Formulation No. 
1*.sup.1 
2*.sup.1 
3*.sup.1 
4*.sup.1 
5*.sup.1 
6*.sup.1 
__________________________________________________________________________ 
(A) N6*.sup.2 25.2 
21.6 
18.0 
-- -- -- 
MXD6*.sup.3 37.8 
32.4 
27.0 
-- -- -- 
BVOH*.sup.4 -- -- -- 72.0 
63.0 
45.0 
(E) Br-poly(isoprene-p-methylstyrene) 
27.0 
36.0 
45.0 
18.0 
27.0 
45.0 
(C) UHMWPE*.sup.5 (.gamma.c = 29 mN/m) 
10 10 10 10 10 10 
Mea- 
Air permeation coefficient 
0.75 
1.37 
2.49 
0.35 
0.65 
2.24 
aure- 
(.times.10.sup.-12 cc .multidot. cm/cm.sup.2 .multidot. s .multidot. 
cmHg) 
ment 
(at 30.degree. C.) 
items 
Young's modulus (MPa) 
321 212 140 435 291 131 
Melt-fusion with rubber 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
__________________________________________________________________________ 
*.sup.1 Example of invention 
*.sup.2 CM4061 (Toray, 6nylon) 
*.sup.3 Reny 6002 (Mitsubishi Gas Chemical copolymer nylon) 
*.sup.4 Eval EPE153B (Kuraray) 
*.sup.5 Hizexmillion (240M) (Mitsui Petrochemical Industries) 
TABLE II-6 
__________________________________________________________________________ 
(Example II-6) 
Comp- 
onent 
Formulation No. 
1 2*.sup.1 
3*.sup.1 
4*.sup.1 
5*.sup.1 
6 7 
__________________________________________________________________________ 
(A) N6*.sup.2 28.0 25.2 
25.2 25.2 
25.2 
25.2 
25.2 
MXD6*.sup.3 42.0 37.8 
37.8 37.8 
37.8 
37.8 
37.8 
(B) Br-poly(isoprene-p-methylstyrene) 
30.0 27.0 
27.0 27.0 
27.0 
27.0 
27.0 
(C) Bondability imparting substance 
Not added 
PP*.sup.4 
EP copolymer*.sup.5 
SBS*.sup.6 
SEBS*.sup.7 
Fluorine 
Polyester TPE*.sup.9 
(each 10 phr added) TPE*.sup.8 
Mea- 
Critical surface tension .gamma.c 
-- 28 28 32 32 23 39 
aure- 
(mN/m) 
ment 
Air permeation coefficient 
0.48 0.79 
1.15 0.98 
1.03 
0.69 
0.74 
items 
(.times.10.sup.-12 cc .multidot. cm/cm.sup.2 .multidot. s .multidot. 
cmHg) 
at (30.degree. C.) 
Young's modulus (MPa) 
299 314 222 217 222 265 312 
Melt-fusion with rubber 
x .smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
x x 
__________________________________________________________________________ 
Note that the facing rubber was SBR/NR (50 parts/50 parts) having .gamma. 
of 30 mN/m 
*.sup.1 Example of invention 
*.sup.2 CM4061 (Toray, 6nylon) 
*.sup.3 Reny 6002 (Mitsubishi Gas Chemical, copolymer nylon) 
*.sup.4 Polypropylene MS230 (Tokuyama Soda) 
*.sup.5 Ethylenepropylene copolymer R210E (Tokuyama Soda) 
*.sup.6 Styrenebutadiene-styrenecopolymer TRKX655 Crayton D (Shell Kagaku 
*.sup.7 Styreneethylene-butadiene-styrenecopolymer G1652 Crayton G (Shell 
Kagaku) 
*.sup.8 Fluorine thermoplastic resin CEFRAL SOFT (Central Glass) 
*.sup.9 Polyester thermoplastic resin Hytrel 5577 (TorayDupont) 
TABLE II-7 
__________________________________________________________________________ 
(Example II-7) 
Comp 
onent 
Formulation No. 
1 2*.sup.1 
3*.sup.1 
4*.sup.1 
5*.sup.1 
6*.sup.1 
7*.sup.1 
8*.sup.1 
9*.sup.1 
10 11 12 
__________________________________________________________________________ 
(A) N6*.sup.2 28.0 
26.6 
25.2 
22.4 
19.6 
16.8 
14.0 
11.2 
8.4 5.6 2.8 -- 
MXD6*.sup.2 
42.0 
39.9 
37.8 
33.6 
29.4 
25.2 
21.0 
16.8 
12.6 
8.4 4.2 -- 
(B) Br-IIR*.sup.3 
30.0 
28.5 
27.0 
24.0 
21.0 
18.0 
15.0 
12.0 
9.0 6.0 3.0 -- 
(C) UHMWPE*.sup.2 (.DELTA..gamma.c = 1) 
0 5 10 20 30 40 50 60 70 80 90 100 
Mea- 
Air permeation coef- 
0.49 
0.62 
0.77 
1.21 
1.90 
2.98 
4.66 
7.30 
11.44 
17.93 
28.09 
44.00 
aure- 
ficient (.times.10.sup.-12 cc .multidot. cm/ 
ment 
cm.sup.2 .multidot. s .multidot. cmHg) 
items 
(at 30.degree. C.) 
Young's modulus (MPa) 
287 298 309 333 358 386 415 447 481 518 557 600 
Melt-fusion with rubber 
x .DELTA. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
__________________________________________________________________________ 
*.sup.1 Example of invention 
*.sup.2 See notes of previous table. 
*.sup.3 BrIIR (Exxon Bromobutyl 2244 Exxon Chemical) 
TABLE II-8 
__________________________________________________________________________ 
(Example II-8) 
Comp 
onent 
Formulation No. 
1 2*.sup.1 
3*.sup.1 
4*.sup.1 
5*.sup.1 
6*.sup.1 
7*.sup.1 
8*.sup.1 
9*.sup.1 
10 11 12 
__________________________________________________________________________ 
(A) N6*.sup.2 28.0 
26.6 
25.2 
22.4 
19.6 
16.8 
14.0 
11.2 
8.4 5.6 2.8 -- 
MXD6*.sup.2 
42.0 
39.9 
37.8 
33.6 
29.4 
25.2 
21.0 
16.8 
12.6 
8.4 4.2 -- 
(B) MAH-g-EPM*.sup.3 
30.0 
28.5 
27.0 
24.0 
21.0 
18.0 
15.0 
12.0 
9.0 6.0 3.0 -- 
(C) UHMWPE*.sup.2 (.DELTA..gamma.c = 1) 
0 5 10 20 30 40 50 60 70 80 90 100 
Mea- 
Air permeation coef- 
1.62 
1.91 
2.26 
3.14 
4.37 
6.08 
8.45 
11.75 
16.35 
22.74 
31.63 
44.00 
aure- 
ficient (.times.10.sup.-12 cc .multidot. cm/ 
ment 
cm.sup.2 .multidot. s .multidot. cmHg) 
items 
(at 30.degree. C.) 
Young's modulus (MPa) 
257 268 279 304 331 360 392 427 465 506 551 600 
Melt-fusion with rubber 
x .DELTA. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
__________________________________________________________________________ 
*.sup.1 Example of invention 
*.sup.2 See notes of previous table. 
*.sup.3 MAHg-EPM: Tafmer MP0610 (Mitsui Petrochemical Industries) 
TABLE II-9 
__________________________________________________________________________ 
(Example II-9) 
Comp 
onent 
Formulation No. 
1 2*.sup.1 
3*.sup.1 
4*.sup.1 
5*.sup.1 
6*.sup.1 
7*.sup.1 
8*.sup.1 
9*.sup.1 
10 11 12 
__________________________________________________________________________ 
(A) N6*.sup.2 28.0 
26.6 
25.2 
22.4 
19.6 
16.8 
14.0 
11.2 
8.4 5.6 2.8 -- 
MXD6*.sup.2 
42.0 
39.9 
37.8 
33.6 
29.4 
25.2 
21.0 
16.8 
12.6 
8.4 4.2 -- 
(B) Br-IIR*.sup.2 
30.0 
28.5 
27.0 
24.0 
21.0 
18.0 
15.0 
12.0 
9.0 6.0 3.0 -- 
(C) EEA*.sup.2 (.DELTA..gamma.c = 3) 
0 5 10 20 30 40 50 60 70 80 90 100 
Mea- 
Air permeation coef- 
0.49 
0.64 
0.84 
1.43 
2.43 
4.13 
7.03 
11.95 
20.33 
34.57 
58.80 
100.00 
aure- 
ficient (.times.10.sup.-12 cc .multidot. cm/ 
ment 
cm.sup.2 .multidot. s .multidot. cmHg) 
items 
(at 30.degree. C.) 
Young's modulus (MPa) 
287 265 244 206 175 148 126 107 90 77 65 55 
Melt-fusion with rubber 
x .DELTA. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
__________________________________________________________________________ 
*.sup.1 Example of invention 
*.sup.2 See notes of previous table. 
TABLE II-10 
__________________________________________________________________________ 
(Example II-10) 
Comp 
onent 
Formulation No. 
1 2*.sup.1 
3*.sup.1 
4*.sup.1 
5*.sup.1 
6*.sup.1 
7*.sup.1 
8*.sup.1 
9*.sup.1 
10 11 12 
__________________________________________________________________________ 
(A) N6*.sup.2 28.0 
26.6 
25.2 
22.4 
19.6 
16.8 
14.0 
11.2 
8.4 5.6 2.8 -- 
MXD6*.sup.2 
42.0 
39.9 
37.8 
33.6 
29.4 
25.2 
21.0 
16.8 
12.6 
8.4 4.2 -- 
(B) MAH-g-EPM*.sup.3 
30.0 
28.5 
27.0 
24.0 
21.0 
18.0 
15.0 
12.0 
9.0 6.0 3.0 -- 
(C) EEA*.sup.2 (.DELTA..gamma.c = 3) 
0 5 10 20 30 40 50 60 70 80 90 100 
Mea- 
Air permeation coef- 
1.62 
#.99 
2.45 
3.70 
5.59 
8.44 
12.74 
19.24 
29.05 
43.86 
66.23 
100.00 
aure- 
ficient (.times.10.sup.-12 cc .multidot. cm/ 
ment 
cm.sup.2 .multidot. s .multidot. cmHg) 
items 
(at 30.degree. C.) 
Young's modulus (MPa) 
257 238 220 189 162 139 119 102 87 75 64 55 
Melt-fusion with rubber 
x .DELTA. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
__________________________________________________________________________ 
*.sup.1 Example of invention 
*.sup.2 See notes of previous table. 
*.sup.3 MAHg-EPM: Tafmer MP0610 (Mitsui Petrochemical Industries) 
TABLE II-11 
__________________________________________________________________________ 
(Example II-11) 
Comp 
onent 
Formulation No. 
1 2*.sup.1 
3*.sup.1 
4*.sup.1 
5*.sup.1 
6*.sup.1 
7*.sup.1 
8*.sup.1 
9*.sup.1 
10 11 12 
__________________________________________________________________________ 
(A) PBT*.sup.3 60.0 
57.0 
54.0 
48.0 
42.0 
36.0 
30.0 
24.0 
18.0 
12.0 
6.0 -- 
(B) Br-IIR*.sup.2 
40.0 
38.0 
36.0 
32.0 
28.0 
24.0 
20.0 
16.0 
12.0 
8.0 4.0 -- 
(C) UHMWPE*.sup.2 (.DELTA..gamma.c = 1) 
0 5 10 20 30 40 50 60 70 80 90 100 
Mea- 
Air permeation coef- 
4.41 
4.95 
5.55 
6.99 
8.79 
11.07 
13.93 
17.53 
22.07 
27.77 
34.96 
44.00 
aure- 
ficient (.times.10.sup.-12 cc .multidot. cm/ 
ment 
cm.sup.2 .multidot. s .multidot. cmHg) 
items 
(at 30.degree. C.) 
Young's modulus (MPa) 
290 301 312 335 361 388 417 449 482 519 558 600 
Melt-fusion with rubber 
x .DELTA. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
__________________________________________________________________________ 
*.sup.1 Example of invention 
*.sup.2 See notes of previous table. 
*.sup.3 PBT: Ultradur B4550 (BASF) 
TABLE II-12 
__________________________________________________________________________ 
(Example II-12) 
Comp 
onent 
Formulation No. 
1 2*.sup.1 
3*.sup.1 
4*.sup.1 
5*.sup.1 
6*.sup.1 
7*.sup.1 
8 9 10 11 12 
__________________________________________________________________________ 
(A) PBT*.sup.2 60.0 
57.0 
54.0 
48.0 
42.0 
36.0 
30.0 
24.0 
18.0 
12.0 
6.0 -- 
(B) Br-IIR*.sup.2 
40.0 
38.0 
36.0 
32.0 
28.9 
24.0 
20.0 
16.0 
12.0 
8.0 4.0 -- 
(C) EEA*.sup.2 (.DELTA..gamma.c = 3) 
0 5 10 20 30 40 50 60 70 80 90 100 
Mea- 
Air permeation coef- 
4.41 
5.15 
6.03 
8.23 
11.25 
15.37 
21.00 
28.69 
39.20 
53.57 
73.19 
100.00 
aure- 
ficient (.times.10.sup.-12 cc .multidot. cm/ 
ment 
cm.sup.2 .multidot. s .multidot. cmHg) 
items 
(at 30.degree. C.) 
Young's modulus (MPa) 
290 267 246 208 176 149 126 107 91 77 65 55 
Melt-fusion with rubber 
x .DELTA. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
__________________________________________________________________________ 
*.sup.1 Example of invention 
*.sup.2 See notes of previous table. 
TABLE II-13 
__________________________________________________________________________ 
(Example II-13) 
Comp 
onent 
Formulation No. 
1 2*.sup.1 
3*.sup.1 
4*.sup.1 
5*.sup.1 
6*.sup.1 
7*.sup.1 
8*.sup.1 
9*.sup.1 
10 11 12 
__________________________________________________________________________ 
(A) PBT*.sup.2 60.0 
57.0 
54.0 
48.0 
42.0 
36.0 
30.0 
24.0 
18.0 
12.0 
6.0 -- 
(B) Br-poly(isoprene- 
40.0 
38.0 
36.0 
32.0 
28.0 
24.0 
20.0 
16.0 
12.0 
8.0 4.0 -- 
p-methylstyrene) 
(C) UHMWPE*.sup.2 (.DELTA..gamma.c = 1) 
0 5 10 20 30 40 50 60 70 80 90 100 
Mea- 
Air permeation coef- 
4.24 
4.77 
5.36 
6.78 
8.56 
10.82 
13.67 
17.27 
21.82 
27.56 
34.83 
44.00 
aure- 
ficient (.times.10.sup.-12 cc .multidot. cm/ 
ment 
cm.sup.2 .multidot. s .multidot. cmHg) 
items 
(at 30.degree. C.) 
Young's modulus (MPa) 
306 316 327 350 374 401 428 458 490 524 561 600 
Melt-fusion with rubber 
x .DELTA. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
__________________________________________________________________________ 
*.sup.1 Example of invention 
*.sup.2 See notes of previous table. 
TABLE II-14 
__________________________________________________________________________ 
(Example II-14) 
Comp 
onent 
Formulation No. 
1 2*.sup.1 
3*.sup.1 
4*.sup.1 
5*.sup.1 
6*.sup.1 
7*.sup.1 
8 9 10 11 12 
__________________________________________________________________________ 
(A) PBT*.sup.2 60.0 
57.0 
54.0 
48.0 
42.0 
36.0 
30.0 
24.0 
18.0 
12.0 
6.0 -- 
(B) Br-poly(isoprene- 
40.0 
38.0 
36.0 
32.0 
28.0 
24.0 
20.0 
16.0 
12.0 
8.0 4.0 -- 
p-methylstyrene) 
(C) EEA*.sup.2 (.DELTA..gamma.c = 3) 
0 5 10 20 30 40 50 60 70 80 90 100 
Mea- 
Air permeation coef- 
4.24 
4.97 
5.82 
7.99 
10.95 
15.02 
20.60 
28.26 
38.76 
53.16 
72.91 
100.00 
aure- 
ficient (.times.10.sup.-12 cc .multidot. cm/ 
ment 
cm.sup.2 .multidot. s .multidot. cmHg) 
items 
(at 30.degree. C.) 
Young's modulus (MPa) 
306 281 258 217 183 154 130 109 92 78 65 55 
Melt-fusion with rubber 
x .DELTA. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
__________________________________________________________________________ 
*.sup.1 Example of invention 
*.sup.2 See notes of previous table. 
Examples II-15 and II-16 and Comparative Examples II-1 and II-2 
Various blending agents were mixed into Br-IIR or 
Br-poly(isoprene-p-methylstyrene) (Br-IPMS) and kneaded in a closed 
Bambury mixer, then a rubber roll was used to form rubber sheets of a 
thickness of 2.5 mm to prepare the master batches A and B. 
The sheets of the master batch A or B were pelletized by a rubber 
pelletizer. The pellets were used to knead the components (A) and (C) with 
the master batch in the various formulations (parts by weight) shown in 
Table II-15 by a b-axial kneader, then a vulcanization system was added 
and the rubber master batch component dispersed as a domain in a resin 
matrix during the kneading was dynamically vulcanized. The elastomer 
component kneaded by the bi-axial kneader was extruded into strands and 
the polymer composition was further pelletized by a resin pelletizer, then 
the pellets were used to prepare films of a width of 350 mm and a 
thickness of 0.05 mm by a resin extruder. The air permeation coefficient 
and the Young's modulus of the resultant films were measured. 
These films were wrapped around tire molding drums, then overlaid with 
carcasses, sidewalls, treads, and other tire members and inflated to 
obtain green tires. The green tires were vulcanized by a vulcanizer at 
185.degree. C. for 15 minutes at a pressure of 2.3 MPa to finish them into 
tires of tire size 165SR13. 
On the other hand, as Comparative Example II-1, a green tire was formed 
having an inner liner layer of about 0.5 mm, comprised of an unvulcanized 
butyl rubber composition shown in the following formulation table on the 
inner surface of the green tire through tie rubber of a thickness of about 
0.7 mm. This was then vulcanized to finish the tire (size 165SR13). 
______________________________________ 
Butyl rubber formulation (unit: parts by weight) 
______________________________________ 
Br-IIR 100 
Carbon black (GPF) 60 
Stearic acid 1 
Petroleum based hydrocarbon resin*.sup.1 
10 
Paraffinic process oil 
10 
No. 3 ZnO 3 
DM 1 
Sulfur 0.6 
______________________________________ 
*.sup.1 Escolets 1102 made by Esso Chemical. 
Further, as Comparative Example II-2, a tire was prepared without using a 
thermoplastic resin with a critical surface tension difference with the 
facing rubber layer of not more than 3 mN/m. 
The weight of the inner liner layer (air permeation prevention layer) of 
the resultant pneumatic tire was measured and an air leakage test and tire 
durability test were run, whereupon the results shown in Table II-15 were 
obtained. 
TABLE II-15 
__________________________________________________________________________ 
Component 
Formulation no. Ex. 15*.sup.1 
Ex. 16*.sup.2 
Comp. Ex. 1 
Comp. Ex. 
__________________________________________________________________________ 
2*.sup.1 
(A) N6*.sup.3 25.2 25.2 General tire using 
28.0l 
MXD6*.sup.3 37.8 37.8 rubber 42.0 
(B) Master batch 48.9 (27) 
48.9 (27) 54.3 (30) 
(C) EEA*.sup.3 10.0 
SBS*.sup.3 10.0 
Cross-linking 
ZnO 1.5 1.5 1.5 
system DM 0.5 0.5 0.5 
Sulfur 0.3 0.3 0.3 
Measurement items 
Air permeation coefficient 
0.54 0.98 55 0.49 
(.times.10.sup.-12 cc .multidot. cm/cm.sup.2 .multidot. s 
.multidot. cmHg) (at 30.degree. C.) 
Young's modulus (MPa) 
244 217 15 287 
Rate of decline of internal pressure 
0.63 0.74 2.7 0.38 
(%/month) 
Inner liner weight (g) 
46 46 650 46 
Tire durability .smallcircle. 
.smallcircle. 
.smallcircle. 
x 
__________________________________________________________________________ 
*.sup.1 Using master batch A of the following formulation: 
Formulation of Master Batch A 
Br-IIR 100 
GPF 60 
Stearic acid 1 
Petroleum based hydrocarbon resin 
10 
Paraffinic process oil 
10 
Br-IIR: Exxon Bromobutyl 2244 (Exxon Chemical) 
GPF: Seast V (Tokai Carbon) 
Petroleum-based hydrocarbon resin: Escolet 1102 (Esso) 
Paraffinic process oil: Machine Oil 22 (Showa Shell Sekiyu) 
*.sup.2 Using master batch B of the following formulation: 
Formulation of Master Batch B 
Br-IPMS (XP-50) 
100 
GPF 60 
Stearic acid 1 
Petroleum based hydrocarbon resin 
10 
Paraffinic process oil 
10 
XP-50: Exxon Butyl (Exxon Chemical) 
GPF: Seast V (Tokai Carbon) 
Petroleum-based hydrocarbon resin: Escolet 1102 (Esso) 
Paraffinic process oil: Machine Oil 22 (Showa Shell Sekiyu) 
*.sup.3 See notes of previous tables. 
As explained above, according to the second aspect of the present 
invention, it is possible to obtain a tire polymer composition which is 
suitable for an air permeation prevention layer for a pneumatic tire which 
enables maintenance of the retention of air pressure in the tire well and 
maintenance of the flexibility, is superior in the bonding with rubber, 
and enables lightening of the weight of the tire. 
Examples III-1 to III-8 and Comparative Examples III-1 to III-2 
The thermoplastic resin component (A) and bondability imparting resin 
component (D) were charged into a first charging port of a bi-axial 
kneader and extruder in the various formulations (parts by weight) shown 
in Table III-1 and kneaded and melted, then the elastomer component (B) 
was charged in from a second charging port and kneaded to make (B) the 
dispersed phase and the components (A) and (C) become the continuous 
phase. The kneaded product was extruded into strands from the front end of 
the bi-axial kneader and extruder, cooled by water, then pelletized by a 
resin pelletizer. The pellets were formed into films of a width of 350 mm 
and a thickness of 0.05 mm by a resin extruder. The films were wrapped 
around tire molding drums, then overlaid with carcasses, sides, belts, 
treads, and other tire members and inflated to form green tires. The green 
tires were vulcanized by a vulcanizer at 185.degree. C. for 15 minutes at 
a pressure of 2.3 MPa to finish them into tires of a tire size 165SR13. 
The films and tires were evaluated as to their various performances. The 
results are shown in Table III-1. 
Comparative Example III-3 
A green tire was formed having an inner liner layer of about 0.5 mm, 
comprised of an unvulcanized butyl rubber of the formulation shown in the 
following table, on the inner surface of the green tire through tie rubber 
of a thickness of about 0.7 mm. This was then vulcanized to finish the 
tire (size 165SR13). The results are shown in Table III-1. 
______________________________________ 
Butyl Rubber Formulation (Unit: Parts by Weight) 
______________________________________ 
Br-IIR*.sup.1 100 
Carbon black (GPF)*.sup.2 
60 
Stearic acid 1 
Petroleum based hydrocarbon resin*.sup.3 
10 
Paraffinic process oil*.sup.4 
10 
No. 3 ZnO 3 
DM 1 
Sulfur 0.6 
______________________________________ 
*.sup.1 Exxon Bromobutyl 2244 (Exxon Chemical) 
*.sup.2 Seast V (Tokai Carbon) 
*.sup.3 Escolets 1102 made by Esso Chemical. 
*.sup.4 Machine oil 22 (ShowaShell Oil) 
TABLE III-1 
__________________________________________________________________________ 
(Parts by weight) 
Formulation Ex. 1 
Ex. 2 Ex. 3 Ex. 4 Ex. 5 Ex. 
__________________________________________________________________________ 
6 
N6*.sup.1 (A) 25.2 25.2 25.2 25.2 25.2 25.2 
MXD6*.sup.2 (A) 37.8 37.8 37.8 37.8 37.8 37.8 
Br-poly(isoprene-p- 
27.0 27.0 27.0 27.0 27.0 27.0 
methylstyrene)*.sup.3 (B) 
Bondability imparting substance 
PP*.sup.4 (10) 
EP copolymer*.sup.5 (10) 
N6/N66/N610*.sup.6 (10) 
N6/N66/N610/N12*.sup.7 (10) 
SEBS*.sup.8 (10) 
EEA*.sup.9 (10) 
(D) (added weight) 
Melting point of bondability 
150.degree. C. 
155.degree. C. 
180.degree. C. 
180.degree. C. 
110.degree. C. 
100.degree. C. 
imparting substance 
Air permeation coefficient 
0.79 1.15 0.63 0.70 1.03 0.82 
(.times.10.sup.-12 cc .multidot. cm/cm.sup.2 .multidot. s .multidot. 
cmHg) 
Young's modulus (MPa) (at 30.degree. C.) 
314 222 317 309 222 252 
Air permeation prevention layer 
0.05 0.05 0.05 0.05 0.05 0.05 
gauge (mm) 
Air permeation prevention layer 
46 46 46 46 46 46 
weight (g) 
Rate off all in internal pressure 
0.61 0.86 0.49 0.54 0.78 0.63 
(%/month) 
Durability of splice portion 
Pass Pass Pass Pass Pass Pass 
Stability of thickness of air 
0.05 0.09 0.06 0.09 0.09 0.10 
permeation prevention layer 
__________________________________________________________________________ 
(Parts by weight) 
Formulation Ex. 7 Ex. 8 Comp. Ex. 1 
Comp. Ex. 
Comp. Ex. 
__________________________________________________________________________ 
3 
N6*.sup.1 (A) 22.4 19.6 28.2 11.2 butyl rubber 
MXD6*.sup.2 (A) 33.6 29.4 42.0 16.8 -- 
Br-poly(isoprene-p-methylstyrene)*.sup.3 (B) 
24.0 21.0 30.0 12.0 -- 
Bondability imparting substance (D) (added weight) 
EEA*.sup.9 (20) 
EEA*.sup.9 (30) 
Not added (0) 
EEA*.sup.9 (60) 
-- 
Melting point of bondability imparting substance 
100.degree. C. 
100.degree. C. 
-- 100.degree. C. 
-- 
Air permeation coefficient (.times.10.sup.-12 cc .multidot. cm/cm.sup.2 
.multidot. s .multidot. cmHg) (at 30.degree. C.) 
1.40 2.38 0.48 11.82 55.00 
Young's modulus (MPa) 213 180 299 108 15 
Air permeation prevention layer gauge (mm) 
0.05 0.05 0.05 0.05 0.5 
Air permeation prevention layer weight (g) 
46 46 46 46 480 
Rate of fall in internal pressure (%/month) 
1.03 1.61 0.38 4.68 3.02 
Durability of splice portion Pass Pass Fail Pass Pass 
Stability of thickness of air permeation prevention layer 
0.10 0.09 -- 0.25 -- 
__________________________________________________________________________ 
*.sup.1 N6: Toray CM4061 
*.sup.2 MXD6: Mitsubishi Gas Chemical Reny 6002 
*.sup.3 Brpoly(isoprene-p-methylstyrene): Exxon Chemical Exxon Butyl XP50 
*.sup.4 PP: Tokuyama Soda MS230 
*.sup.5 EP copolymer: Tokuyama Soda R210E 
*.sup.6 N6/N66/N610: Toray CM4001 
*.sup.7 N6/N66/N610/N12: Toray CM8001 
*.sup.8 SEBS: Shell Kagaku Crayton G G1652 
*.sup.9 EEA: Unitika NUC6070 
Examples 3 and 4 used compatibility agents and maleic acid modified 
polyolefins. 
Examples III-9 to III-17 and Comparative Examples III-4 to III-6 
Films obtained in the same way as in Examples III-1 to III-8 and 
Comparative Examples III-1 to III-3 except that the elastomer components 
were changed to Br-IIR and films obtained using PBT as the thermoplastic 
resin and Br-IIR as the elastomer component were used to prepare tires by 
the same method as in Example III-1. The performances of the tires were 
evaluated. The results are shown in Table III-2. 
TABLE III-2 
__________________________________________________________________________ 
(Parts by weight) 
Ex. Ex. Ex. Ex. Ex. 
Formulation Ex. III-9 
Ex. III-10 
Ex. III-11 
Ex. III-12 
III-13 
III-14 
III-15 
III-16 
III-17 
__________________________________________________________________________ 
N6*.sup.1 (A) 25.2 25.2 25.2 25.2 25.2 
25.2 
22.4 
19.6 
PBT*.sup.10 (A) 54.0 
MXD6*.sup.2 (A) 
37.8 37.8 37.8 37.8 37.8 
37.8 
33.6 
29.4 
Br-IIR*.sup.3 (B) 
27.0 27.0 27.0 27.0 27.0 
27.0 
24.0 
21.0 36.0 
Bondability imparting substance 
PP*.sup.4 
EP copolymer*.sup.5 
N6/N66/ 
N6/N66/N610/ 
SEBS*.sup.8 
EEA*.sup.9 
EEA*.sup.9 
EEA*.sup.9 
EEA*.sup.9 
(D) (added weight) 
(10) (10) N610*.sup.6 (10) 
N12*.sup.7 (10) 
(10) 
(10) 
(20) 
(30) (10) 
Melting point of bondability 
150.degree. C. 
155.degree. C. 
180.degree. C. 
180.degree. C. 
110.degree. C. 
100.degree. C. 
100.degree. C. 
100.degree. 
100.degree. 
C. 
imparting substance 
Air permeation coefficient(30.degree. C.) 
0.81 1.18 0.65 0.72 1.06 
0.84 
1.43 
2.43 6.03 
(.times.10.sup.-12 cc .multidot. cm/cm.sup.2 .multidot. s .multidot. 
cmHg) 
Young's modulus (MPa) 
302 214 305 298 214 244 206 175 246 
Air permeation prevention layer 
0.05 0.05 0.05 0.05 0.05 
0.05 
0.05 
0.05 0.05 
gauge (mm) 
Air permeation prevention layer 
46 46 46 46 46 46 46 46 46 
weight (g) 
Rate of fall in internal pressure 
0.62 0.88 0.51 0.56 0.80 
0.64 
1.04 
1.64 3.21 
(%/month) 
Durability of splice portion 
Pass Pass Pass Pass Pass 
Pass 
Pass 
Pass Pass 
Stability of thickness of air 
0.06 0.10 0.06 0.09 0.10 
0.09 
0.10 
0.09 0.08 
permeation prevention layer 
__________________________________________________________________________ 
*.sup.1 N6: Toray CM4061 
*.sup.2 MXD6: Mitsubishi Gas Chemical Reny 6002 
*.sup.3 BrIIR: Exxon Chemical Exxon Bromobutyl 2244 
*.sup.4 PP: Tokuyama Soda MS230 
*.sup.5 EP copolymer: Tokuyama Soda R210E 
*.sup.6 N6/N66/N610: Toray CM4001 
*.sup.7 N6/N66/N610/N12: Toray CM8001 
*.sup.8 SEBS: Shell Kagaku Crayton G G1652 
*.sup.9 EEA: Unitika NUC6070 
*.sup.10 PBT: BASF: Ultradur B4550 
Examples 11 and 12 used compatibility agents and maleic acid modified 
polyolefins. 
(Parts by weight) 
Formulation Comp. Ex. III-3 
Comp. Ex. III-4 
Comp. Ex. 
Comp. Ex. 
__________________________________________________________________________ 
III-6 
N6*.sup.1 (A) butyl rubber 
28.2 11.2 25.2 
PBT*.sup.10 (A) 
MXD6*.sup.2 (A) -- 42.0 16.8 37.8 
Br-IIR*.sup.3 (B) -- 30.0 12.0 27.0 
Bondability imparting substance 
-- not added(0) 
EEA*.sup.9 (60) 
*.sup.10 (10) 
(D) (added weight) 
Melting point of bondability -- -- 100.degree. C. 
290.degree. C. 
imparting substance 
Air permeation coefficient (.times.10.sup.-12 cc .multidot. cm/cm.sup.2 
.multidot. s .multidot. cmHg) 
55.0 0.49 11.95 0.78 
at (30.degree. C.) 
Young's modulus (MPa) 15 287 107 347 
Air permeation prevention layer 
0.5 0.05 0.05 0.05 
gauge (mm) 
Air permeation prevention layer 
480 46 46 46 
weight (g) 
Rate of fall in internal pressure 
3.02 0.39 4.71 0.60 
(%/month) 
Durability of splice portion Pass Fail Pass Fail 
Stability of thickness of air permeation prevention layer 
-- -- 0.25 -- 
__________________________________________________________________________ 
*.sup.1 N6: Toray CM4061 
*.sup.2 MXD6: Mitsubishi Gas Chemical Reny 6002 
*.sup.3 BrIIR: Exxon Chemical Exxon Bromobutyl 2244 
*.sup.4 PP: Tokuyama Soda MS230 
*.sup.5 EP copolymer: Tokuyama Soda R210E 
*.sup.6 N6/N66/N610: Toray CM4001 
*.sup.7 N6/N66/N610/N12: Toray CM8001 
*.sup.8 SEBS: Shell Kagaku Crayton G G1652 
*.sup.9 EEA: Unitika NUC6070 
*.sup.10 : Polyacrylate Resin: Unitika U100 
Examples III-18 to III-20 
Various blending agents, except the vulcanization agent, were mixed into 
Br-IIR and Br-IPMS to prepare the master batches A and B in a closed 
Bambury mixer. The master batches of the rubber composition were formed 
into sheets of a thickness of 3 mm by a rubber roll which were then 
pelletized using a rubber pelletizer. The formulations of the master 
batches are shown in Table III-3. 
TABLE III-3 
______________________________________ 
Formulation of Master Batches 
Master 
Master 
batch A 
batch B 
______________________________________ 
Br-IIR 100 -- 
Br-IPMS -- 100 
Carbon black (GPF) 60 60 
Stearic acid 1 -- 
Petroleum based hydrocarbon 
10 -- 
resin 
Paraffinic process oil 
10 20 
______________________________________ 
The thermoplastic resin component (A) and bondability imparting resin 
component (D) were charged into a first charging port of a bi-axial 
extruder in the various formulations (parts by weight) shown in Table 
III-4 and kneaded and melted, then the master batch (B) was charged from 
the second charging port and kneaded so that (B) became the dispersed 
phase and the components (A) and (D) became the continuous phase. 
Further, the vulcanization agent etc. were charged from a third charging 
port and the dispersed elastomer layer was made to cross-link and cure. 
The mixture was extruded into strands from the front end of the bi-axial 
kneader and extruder and cooled with water, then pelletized using a resin 
pelletizer. The pellets were formed into films of a width of 350 mm and a 
thickness of 0.05 mm by a resin extruder. The air permeation coefficient 
and the Young's modulus of the resultant films were measured. Further, the 
films were wrapped around tire molding drums, then overlaid with 
carcasses, sidewalls, treads, and other tire members and inflated to 
obtain green tires. The green tires were vulcanized by a vulcanizer at 
185.degree. C. for 15 minutes at a pressure of 2.3 MPa to finish them into 
tires of tire size 165SR13. 
The weights of the inner liners of the pneumatic tires obtained were 
measured and air leakage tests were performed. The results are shown in 
Table III-4. 
TABLE III-4 
__________________________________________________________________________ 
Ex. III-18 
Ex. III-19 
Ex. III-20 
__________________________________________________________________________ 
N6 (A) 25.2 25.2 25.2 
MXD6 (A) 37.8 37.8 37.8 
Master batch A (B) 67 67 -- 
Master batch B (B) -- -- 67 
ZnO 1.8 1.2 0.2 
DM 0.6 0.4 -- 
Sulfur 0.3 0.2 -- 
Stearic acid -- -- 0.8 
Zinc stearate -- -- 0.4 
Bondability imparting substance (D) (added weight) 
N6/N66/N610/N12(10) 
EEA(10) 
N6/N66/N610/N12(10) 
Melting point of bondability imparting substance 
180.degree. C. 
100.degree. C. 
180.degree. C. 
Air permeation coefficient (30.degree. C.) (.times.10.sup.-12 cc 
.multidot. cm/cm.sup.2 .multidot. sec .multidot. cmHg) 
0.65 0.81 0.68 
Young's modulus (MPa) 300 248 310 
Air permeation prevention layer gauge (mm) 
0.05 0.05 0.05 
Air permeation prevention layer weight (g) 
48 48 48 
Rate of fall in internal pressure (%/month) 
0.55 0.64 0.55 
Durability of splice portion Pass Pass Pass 
Stability of thickness of air permeation prevention layer 
0.09 0.10 0.09 
__________________________________________________________________________ 
As explained above, according to the third aspect of the present invention, 
it is possible to obtain a pneumatic tire having an air permeation 
prevention layer which enables maintenance of the retention of air 
pressure in the tire well and maintenance of the flexibility, is superior 
in the bonding with rubber, is superior in bonding with layers such as the 
liner layer during molding of the tire, and enables lightening of the 
weight of the tire. 
Examples IV-1 to IV-3 
For the combinations of the air permeation prevention layers comprised of 
the various thermoplastic resins (A) and elastomer components (B) with the 
bondability imparting layers in the formulations (parts by weight) and 
constitutions shown in Table IV-1 to Table IV-3, the air permeation 
prevention layers (thickness of 0.05 mm) before lamination were formed 
into sheets of a width of 350 mm by an ordinary resin extruder and were 
evaluated in the air permeation coefficient and Young's modulus. Next, 
these films were wrapped around tire molding drums, then the similarly 
prepared 0.02 mm films of the bondability imparting layers were wrapped, 
then these were overlaid with carcasses, sidewalls, treads, and other tire 
members and inflated to form green tires. The green tires were vulcanized 
by a vulcanizer at 185.degree. C. for 15 minutes at a pressure of 2.3 MPa 
to finish them into tires of a tire size of 165SR13. The rate of reduction 
in the internal pressure of these tires and the tire durabilities were 
evaluated. The results are shown in Table IV-1 to Table IV-3. 
TABLE IV-1 
__________________________________________________________________________ 
(Ex. IV-1) 
(Parts by weight) 
Formulation no. 1 2*.sup.1 
3*.sup.1 
4*.sup.1 
5*.sup.1 
6*.sup.1 
7 8 
__________________________________________________________________________ 
Air permeation prevention layer 
N6*.sup.2 (A) 28.0 
28.0 
28.0 28.0 
28.0 
28.0 
28.0 28.0 
MXD6*.sup.3 (A) 42.0 
42.0 
42.0 42.0 
42.0 
42.0 
42.0 42.0 
Br-poly(isoprene-p-methylstyrene)*.sup.4 (B) 
30.0 
30.0 
30.0 30.0 
30.0 
30.0 
30.0 30.0 
Critical surface tension .gamma.c (mN/m) 
35 35 35 35 35 35 35 
Bondability imparting layer 
Non 
PP*.sup.5 
EP copolymer*.sup.9 
SBS*.sup.7 
SEBS*.sup.8 
EEA*.sup.9 
Fluorine 
Polyester 
TPE*.sup.11 
Critical surface tension .gamma.c (mN/m) 
28 28 32 32 27 23 39 
Air permeation coefficient (30.degree. C.) (.times.10.sup.-12 
0.48 
0.48 
0.48 0.48 
0.48 
0.48 
0.48 0.48 
cc .multidot. cm/cm.sup.2 .multidot. sec .multidot. cmHg) 
Young's modulus (MPa) 
299 
299 299 299 299 299 299 299 
Air permeation prevention layer gauge (mm) 
0.05 
0.05 
0.05 0.05 
0.05 
0.05 
0.05 0.05 
Air permeation prevention layer weight (g) 
46 46 46 46 46 46 46 46 
Rate of fall in internal pressure (%/month) 
0.38 
0.38 
0.38 0.38 
0.38 
0.38 
0.38 0.38 
Tire durability x .smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
x x 
__________________________________________________________________________ 
Note: Facing bonded rubber is SBR/NR (50 parts/50 parts) with .gamma.c of 
30 mN/m. 
*.sup.1 Example of invention. 
*.sup.2 N6: Toray CM4061 
*.sup.3 MXD6: Mitsubishi Gas Chemical Reny 6002 
*.sup.4 Brpoly(isoprene-p-methylstyrene): Exxon Chemical Exxon Butyl XP50 
*.sup.5 PP: Tokuyama Soda MS230 
*.sup.6 EP copolymer: Tokuyama Soda R210E 
*.sup.7 SBS: Shell Kagaku Crayton D TRKX655 
*.sup.8 SEBS: Shell Kagaku Crayton G G1652 
*.sup.9 EEA: Unitika NUC6070 
*.sup.10 Fluorine TPE: Central Glass CEFRAL SOFT 
*.sup.11 Polyester TPE: TorayDupont Hytrel 5577 
*.sup.5, *.sup.6, and *.sup.9 have added as compatibility agents Mitsui 
Petrochemicals maleic acid modified polyethylene propylene resin Tafmer 
MP0610 in 10% by weight with respect to total weight of resin. 
TABLE IV-2 
__________________________________________________________________________ 
(Ex. IV-2) 
(Parts by weight) 
Formulation no. 1*.sup.1 
2*.sup.1 
3*.sup.1 
4*.sup.1 
5*.sup.1 
6*.sup.1 
__________________________________________________________________________ 
Air permeation prevention layer 
N6*.sup.2 (A) 28.0 
24.0 
20.0 
-- -- -- 
MXD6*.sup.3 (A) 42.0 
36.0 
30.0 
-- -- -- 
EVOH*.sup.4 (A) -- -- -- 80.0 
70.0 
50.0 
Br-poly(isoprene-p-methylstyrene)*.sup.5 (B) 
30.0 
40.0 
50.0 
20.0 
30.0 
50.0 
Critical surface tension .gamma.c (mN/m) 
35 33 32 31 31 30 
Bondability imparting layer (UHMWPE*.sup.6) (.gamma.c = 29) 
Yes 
Yes 
Yes 
Yes 
Yes 
Yes 
Air-permeation coefficient(30.degree. C.) (.times.10.sup.-12 
0.48 
0.93 
1.81 
0.21 
0.41 
1.61 
cc .multidot. cm/cm.sup.2 .multidot. sec .multidot. cmHg 
Young's modulus (MPa) 299 
189 
119 
419 
269 
111 
Air permeation prevention layer gauge (mm) 
0.05 
0.05 
0.05 
0.05 
0.05 
0.05 
Air permeation prevention layer weight (g) 
46 46 46 46 46 46 
Rate of fall in internal pressure (%/month) 
0.38 
0.71 
1.28 
0.17 
0.33 
1.16 
Tire durability .smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
__________________________________________________________________________ 
Note: Facing bonded rubber is SBR/NR (50 parts/50 parts) with .gamma.c of 
30 mN/m. 
*.sup.1 Examples of invention. 
*.sup.2 N6: Toray CM4061 
*.sup.3 MXD6: Mitsubishi Gas Chemical Reny 6002 
*.sup.4 EVOH: Kuraray Eval EPE153B 
*.sup.5 Brpoly(isoprene-p-methylstyrene): Exxon Chemical Exxon Butyl XP50 
*.sup.6 UHMWPE: Mitsui Petrochemical Hizexmillion (240M) 
The bondability imparting layers of formulation nos. 1 and 2 similarly 
have added as compatibility agents Mitsui Petrochemical's maleic acid 
modified polyethylene propylene resin Tafmer MP0610 in 10% by weight with 
respect to total weight of resin. 
TABLE IV-3 
__________________________________________________________________________ 
(Ex. IV-3) 
(Parts by weight) 
Formulation no. 1*.sup.1 
2*.sup.1 
3*.sup.1 
4*.sup.1 
5*.sup.1 
6*.sup.1 
7 
__________________________________________________________________________ 
Air permeation prevention layer 
N6*.sup.2 (A) 28.0 
25.2 
22.4 
19.6 
16.8 
14.0 
5.6 
MXD6*.sup.3 (A) 42.0 
37.8 
33.6 
29.4 
25.2 
21.0 
8.4 
Br-poly(isoprene-p-methylstyrene)*.sup.4 (B) 
30.0 
27.0 
24.0 
21.0 
18.0 
15.0 
6.0 
EEA*.sup.5 (A) -- 10.0 
20.0 
30.0 
40.0 
50.0 
80.0 
Critical surface tension .gamma.c (mN/m) 
35 32 30 30 29 29 27 
Bondability imparting layer (UHMWPE*.sup.6) 
Yes 
Yes 
Yes 
Yes 
Yes 
Yes 
Yes 
(critical surface tension .gamma.c = 29 mN/m) 
Air permeation coefficient(30.degree. C.) (.times.10.sup.-12 
0.48 
0.82 
1.40 
2.38 
4.06 
6.93 
34.38 
cc .multidot. cm/cm.sup.2 .multidot. sec .multidot. cmHg) 
Young's modulus (MPa) 
299 
252 
213 
180 
152 
128 
77 
Air permeation prevention layer gauge (mm) 
0.05 
0.05 
0.05 
0.05 
0.05 
0.05 
0.05 
Air permeation prevention layer weight (g) 
46 46 46 46 46 46 46 
Rate of fall in internal pressure (%/month) 
0.38 
0.63 
1.03 
1.61 
2.44 
3.50 
6.83 
Tire durability .smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
.smallcircle. 
__________________________________________________________________________ 
Note: Facing bonded rubber is SBR/NR (50 parts/50 parts) with .gamma.c of 
30 mN/m. 
*.sup.1 Examples of invention. 
*.sup.2 N6: Toray CM4061 
*.sup.3 MXD6: Mitsubishi Gas Chemical Reny 602 
*.sup.4 Brpoly(isoprene-p-methylstyrene): Exxon Chemical Exxon Butyl XP50 
*.sup.5 EEA: Unitika NUC6070 
*.sup.6 UHMWPE: Mitsui Petrochemical Hizexmillion (240M) 
The bondability imparting layer of formulation no. 1 similarly has added 
as compatibility agents Mitsui Petrochemical's maleic acid modified 
polyethylene propylene resin Tafmer MP0610 in 10% by weight with respect 
to total weight of resin. 
Example IV-4 and Comparative Example IV-1 
Various blending agents were mixed with Br-IIR or 
BR-poly(isoprene-p-methylstyrene) (Br-IPMS) to prepare the master batches 
A and B in a closed Bambury mixer. 
The master batch A or B was pelletized using a rubber pelletizer and the 
pellets were kneaded by a bi-axial kneader in the various formulations 
(parts by weight) shown in Table IV-4. These polymer compositions were 
pelletized by a resin pelletizer, then were extruded by a resin extruder 
to form films of a width of 350 mm and a thickness of 0.05 mm. The air 
permeation coefficient and Young's modulus of the resultant films were 
measured. 
These films were wrapped around tire molding drums, then films of 0.02 mm 
of ethylene-ethylacrylate copolymer (EEA) were wrapped around them as 
bondability imparting layers, then these were overlaid with carcasses, 
sidewalls, treads, and other tire members and inflated to obtain green 
tires. The green tires were vulcanized by a vulcanizer at 185.degree. C. 
for 15 minutes at a pressure of 2.3 MPa to finish them into tires of tire 
size 165SR13. 
On the other hand, as a comparative example, a green tire was formed having 
an inner liner layer of about 0.5 mm, comprised of an unvulcanized butyl 
rubber composition shown in the following formulation table, on the inner 
surface of the green tire through tie rubber of a thickness of about 0.7 
mm. This was then vulcanized to finish the tire (size 165SR13). 
______________________________________ 
Butyl Rubber Formulation (Unit: Parts by weight) 
______________________________________ 
Br-IIR 100 
Carbon black (GPF) 60 
Stearic acid 1 
Petroleum based hydrocarbon resin*.sup.1 
10 
Paraffinic process oil 
10 
No. 3 ZnO 3 
DM 1 
Sulfur 0.6 
______________________________________ 
*.sup.1 Escolets 1102 made by Esso Chemical. 
The weights of the inner liner layers of the obtained pneumatic tires were 
measured and air leakage tests and tire durability tests were run. The 
results are shown in Table IV-4. 
TABLE IV-4 
__________________________________________________________________________ 
Formulation no. Ex. IV-4-1*.sup.1 
Ex. IV-4-2*.sup.2 
Comp. Ex. IV-1 
__________________________________________________________________________ 
N6*.sup.3 (A) 25.2 25.2 General tire using butyl rubber 
MXD6*.sup.3 (A) 37.8 37.8 
Master batch (B) 48.9 (27) 
48.9 (27) 
ZnO 1.5 1.5 
DM 0.5 0.5 
Sulfur 0.3 0.3 
Air permeation coefficient (.times.10.sup.-12 
0.84 0.98 55 
cc .multidot. cm/cm.sup.2 .multidot. sec .multidot. cmHg)(at 30.degree. 
C.) 
Young's modulus (MPa) 
244 217 12.2 
Rate of fall in internal pressure (%/month) 
0.63 0.74 2.7 
Air permeation prevention layer weight (g) 
46 46 650 
Tire durability .smallcircle. 
.smallcircle. 
.smallcircle. 
__________________________________________________________________________ 
*.sup.1 Using master batch A of the following formulation: 
Formulation of Master Batch A 
Br-IIR 100 
GPF 60 
Stearic acid 1 
Petroleum based hydrocarbon resin 
10 
Paraffinic process oil 
10 
Br-IIR: Exxon Bromobutyl 2244 (Exxon Chemical) 
GPF: Seast V (Tokai Carbon) 
Petroleum-based hydrocarbon resin: Escorez 1102 (Esso) 
Paraffinic process oil: Machine Oil 22 (Showa Shell Sekiyu) 
*.sup.2 Using master batch B of the following formulation: 
Formulation of Master Batch B 
Br-IPMS (XP-50) 
100 
GPF 60 
Stearic acid 1 
Petroleum based hydrocarbon resin 
10 
Paraffinic process oil 
10 
XP-50: Br-IPMS (Exxon Chemical) 
GPF: Seast V (Tokai Carbon) 
Petroleum-based hydrocarbon resin: Escorez 1102 (Esso) 
Paraffinic process oil: Machine Oil 22 (Showa Shell Sekiyu) 
*.sup.3 See notes of previous tables. 
As explained above, according to the fourth aspect of the present 
invention, it is possible to obtain a pneumatic tire which enables 
maintenance of the retention of air pressure in the tire well and 
maintenance of the flexibility, is superior in the bonding with rubber, 
and enables lightening of the weight of the tire.