Composition for forming water-permeable material water-permeable material and process for producing the same

A water-permeable material having good chemical resistance, water resistance and weatherability and in which cracks do not form in the material. The composition for forming a water-permeable material includes aggregate grains, a polysulfide-modified epoxy resin and a curing agent for the polysulfide-modified epoxy resin.

TECHNICAL FIELD 
The present invention relates to a composition for forming a 
water-permeable material and process for producing the same. More 
particularly, the present invention relates to a composition containing 
aggregate and a resin for forming a water-permeable material, a process 
for producing the water-permeable material and a method for applying the 
same. 
BACKGROUND ART 
Water-permeable materials are recently more and more widely used for 
forming footpaths, roadways, plazas, dry riverbeds, banks, roofs of 
buildings, parking spaces, swimming pool sides and the like in order to 
promote the drainage. Water-permeable materials not only improve 
environment by virtue of their good drainage, but also have good outer 
appearances. 
These water-permeable materials are in the form of plates and blocks and 
are produced by molding a composition for forming the water-permeable 
material, which composition generally comprises aggregate grains, a 
synthetic resin binder and a curing agent of the synthetic resin binder. 
The aggregate grains contained in the compositions for forming the 
water-permeable materials are naturally occurring stones, grains obtained 
by processing naturally occurring stones, balls made of ceramics such as 
pottery, spherical sintered grains made of a mixture of wood-containing 
clay and clay feldspar. As the synthetic resin binder, epoxy resins are 
generally employed. The epoxy resins employed are those which have 
glycidyl groups at the end, such as bisphenol A type and bisphenol F type 
epoxy resins which are copolymers of bisphenol A or bisphenol F and 
epichlorohydrin. Such a synthetic resin binder is added to the aggregate 
in an amount that it can just bind the aggregate grains so that the 
obtained material exhibits water permeability (see, for example, Japanese 
Laid-open Patent Application (Kokai) Nos. 51-133350, 1-51349 and 2-148003. 
The water-permeable materials are generally molded as follows: 
(1) Aggregate grains and a curable resin liquid in an amount necessary for 
binding the aggregate grains are sufficiently mixed; 
(2) The obtained composition is spread on a conditioned floor to a uniform 
thickness using a rake or the like; and 
(3) A flat surface is given to the composition using a trowel or the like. 
Although the operation using the trowel is similar to that for applying a 
cement mortar, application of the water-permeable material is different 
from the application of the cement mortar in that aggregate grains covered 
with the resin liquid are applied. Since the viscosity of the resin liquid 
increases with time because of the proceeding of the reaction, the 
composition adheres to the trowel, so that it is necessary to frequently 
wipe off the composition using an organic solvent such as a thinner. Thus, 
it is not practical to carry out the application by a machine. 
The water-permeable materials made from the conventional compositions 
described above have the following drawbacks: 
(i) The weatherability is insufficient and the material is deteriorated to 
become brittle or colored with time. Such deterioration mainly occurs in 
the regions of epoxy resin used as a binder. 
(ii) The material is elongated or shrunk due to the stress given by the 
repetition of heating and cooling, or to the external load, so that cracks 
tend to be formed. Although formation of the cracks due to the elongation 
and shrinkage can be prevented by providing joints, providing joints is 
troublesome and appearance of the material is also deteriorated. 
(iii) The conditions for application of the composition are influenced by 
the weather, that is, by rain, dew, snow, freezing or the like. As a 
result, curing may be insufficient or the material may be whitened. In 
order to avoid such undesired consequences, it is necessary to apply the 
composition only in good weather. Therefore, the time period necessary for 
the construction may be prolonged. 
(iv) The chemical resistance of the materials is insufficient. Therefore, 
if an acid, alkali, soft drink such as juice, organic solvent or the like 
is attached to the material, the material is easily colored or 
deteriorated. 
It is thought that these problems with the water-permeable materials are 
mainly caused by the synthetic resin binder components. 
The conventional method for applying the water-permeable material has the 
following problems: 
(1) When the water-permeable material is applied with a trowel, the resin 
and the aggregate adhere to the trowel surface. As a result, the 
slipperiness of the trowel is deteriorated, so that the efficiency of the 
operation is decreased and the quality of the finishing is poor. 
(2) In order to remove the material attached to the trowel surface so as to 
improve the slipperiness, a thinner (organic solvent) is used. However, 
use of a thinner presents the following problems: 
(i) Odor and safety. 
(ii) The solvent attached to the surface of the trowel dissolves and flow 
out the resin on the surfaces of the aggregate grains in the finishing 
step, so that the binding force of the aggregate grains in the vicinity of 
the surface is decreased. 
(iii) Spilt organic solvent dissolves the resin on the aggregate grains 
inside the material, so that the strength of the portion of the layer is 
decreased and the strength of the material is thus made non-uniform. 
(iv) The solvent from the surface of the trowel dissolves the resin layer 
in the surface of the material, so that the curing of the resin is 
delayed. As a result, the viscousness of the surface is retained, so that 
dusts tend to be attached. 
(v) The solvent is evaporated during operation and the trowel tends to 
become heavy. Therefore, it is difficult to uniformly slip and press the 
trowel. As a result, the flatness of the material is not good and the 
surface of the material is irregular. Thus, the quality of the finishing 
is poor and the outer appearance is not good. 
(3) Because of the above-mentioned (1) and (2), a machine cannot be well 
used. 
The object of the present invention is to make an improvement such that a 
water-permeable material which has good weatherability and chemical 
resistance, in which cracks are hardly formed, can be easily produced. 
Another object is to overcome the above-mentioned problems on the 
application of the water-permeable material, thereby improving the 
efficiency of the application and performance of the finished product. 
DISCLOSURE OF THE INVENTION 
The composition for forming a water-permeable material according to the 
present invention comprises aggregate grains, a sulfur-modified epoxy 
resin and a curing agent for the sulfur-modified epoxy resin. 
In the composition for forming a water-permeable material according to the 
present invention, the aggregate grains are, for example, spherical 
ceramic grains having an average diameter of not more than 1 cm. The 
sulfur-modified epoxy resin comprises, for example, repeating units of 
diethylformalpolysulfide. 
The process for producing a water-permeable material according to the 
present invention comprises the steps of: 
providing a composition comprising aggregate grains, a sulfur-modified 
epoxy resin and a curing agent for the sulfur-modified epoxy resin; and 
molding the above-mentioned composition into a desired shape and curing the 
composition. 
Aggregate Grains 
The aggregate grains used in the present invention are made of a hard 
metal, a hard inorganic material, a polymer material containing inorganic 
powder or the like which are known stable materials that do not undergo 
vigorous chemical reactions such as ignition at room temperature under 
atmospheric pressure. 
Examples of the hard metal materials include iron, nickel-cobalt alloys, 
stainless steels, brass, copper and aluminum. Examples of the hard 
inorganic materials include naturally occurring various minerals, stones, 
gravel, pebbles, jewels, glass, pottery, porcelain, sintered material, 
concrete and mortar. Examples of the composite materials include those 
prepared by kneading inorganic fine powder of calcium carbonate, alumina, 
talc, silica, kaolin, aluminum hydroxide, siliceous sand, carbon, cement, 
fry ash or the like with a thermoplastic resin such as polyethylene resin, 
polypropylene resin, polystyrene resin, ethylene-vinyl acetate copolymer 
resin, polyvinylchloride resin or polyester resin, and by molding the 
mixture into the form of grains. 
The shape of the above-mentioned aggregate grains may preferably be 
spherical (curved surface) having substantially no edges. Such aggregate 
grains may preferably have a longer diameter/shorter diameter ratio of 
about 1-3. The aggregate grains may have more or less irregular portions. 
Such more or less irregular portions are advantageous for promoting the 
adhesiveness among the aggregate grains. 
The aggregate grains have an average particle size of 0.5-20 mm, preferably 
1-10 mm, more preferably 1.5-6 mm. If the average particle size is less 
than 0.5 mm, the water-permeable material is easily clogged, so that the 
water-permeablity of the material is decreased. On the other hand, if the 
average particle size is more than 20 mm, the feeling when walking and 
outer appearance are deteriorated. When the aggregate grains are not 
spherical, the average particle size means the average of (longer 
diameter+shorter diameter)/2. 
The above-mentioned aggregate grains may contain a small amount of adhered 
grains, in which a plurality of individual grains are adhered, that occur 
during production process of the grains. However, inclusion of such 
adhered grains in a small amount does not matter. 
Two or more types of the above-mentioned aggregate grains may be employed 
in combination. For example, by mixing aggregate grains made of different 
materials or having different sizes, shapes, colors and the like, a 
water-permeable material having a good outer appearance may be obtained. 
In order to promote the adhesiveness of the aggregate grains with the resin 
hereinbelow described, a primer containing an aminosilane, urethane or 
alkoxysilane may be applied to the aggregate grains. 
Epoxy Resin The synthetic resin binder component employed in the present 
invention is an epoxy resin modified with a sulfur atom. The 
sulfur-modified epoxy resin is represented by the general formula (1): 
##STR1## 
In the formula, R.sup.1 and R.sup.2 represent organic groups such as 
alkylene groups. Examples of R.sup.1 and R.sup.2 include those represented 
by the following general formulae: 
##STR2## 
In the above-described general formulae representing R.sup.1 and R.sup.2, 
m means an integer of not less than 1. R.sup.1 and R.sup.2 may be the same 
organic group or may be the different organic groups. In the 
above-described general formula (1), R.sup.3 and R.sup.4 represent 
residues of an epoxy prepolymer having not less than 2 epoxy groups in one 
molecule. Examples of R.sup.3 and R.sup.4 include the residues of the 
epoxy prepolymers represented by the following general formulae: 
##STR3## 
In the above-described general formulae showing R.sup.3 and R.sup.4, n 
represents an integer of not less than 1 and R.sup.5 represents H or 
CH.sub.3. R.sup.3 and R.sup.4 may be the same prepolymer residue or may be 
different prepolymer residues. 
In the above-described general formula (1), X and Y represent the following 
substituent groups: 
EQU --S--, --O--, --NH--. 
X and Y may be the same group or may be different groups. 
In the above-described general formula (1), a represents an integer of 0-5 
and b represents an integer of 1-50, with the proviso that when a is 0, at 
least one of the above-mentioned X and Y is --S-- group. 
The above-described sulfur-modified epoxy resin may be synthesized by 
addition reaction between a sulfur-containing polymer or oligomer having a 
sulfur bond group such as --S-- group, --S--S-- group, --S--S--S-- group, 
--S--S--S--S-- group or --S--S--S--S--S-- group and having at its both 
ends functional groups which can react with epoxy group, such as --OH 
group, --NH.sub.2 group, --NRH group (R represents an organic group) or 
--SH, and an epoxy prepolymer having not less than two epoxy groups in one 
molecule. 
As the epoxy prepolymer employed for the synthesis of the 
polysulfide-modified epoxy resin, those having not less than two epoxy 
groups in one molecule, which are synthesized by condensation reaction 
between an aliphatic polyol or an aromatic polyol and epichlorohydrin are 
employed. Examples of the epoxy prepolymers include epoxy resins of 
bisphenol types such as bisphenol A type epoxy resins, bisphenol F type 
epoxy resins and halogenated bisphenol A type epoxy resins, as well as 
epoxy resins having similar molecular structures to these types of epoxy 
resins. 
In the synthesis, twice or more equivalents of the above-mentioned epoxy 
prepolymer is reacted with the sulfur-containing polymer or the 
sulfur-containing oligomer. 
Among the polysulfide-modified epoxy resins employed in the present 
invention, especially preferred are those in which R.sup.1 in the general 
formula (1) is of diethylformal structure of the following formula (2): 
##STR4## 
wherein m represents an integer of not less than 1. 
Two or more types of the above-described sulfur-modified epoxy resin may be 
employed in combination. However, it is preferred to adjust the mixing 
ratio such that the average of the value a is between 1.5 and 2.5. 
Specific examples of the sulfur-modified epoxy resins employed in the 
present invention include "FLEP"-10, "FLEP-50", "FLEP"-60 and "FLEP"-80 
which are commercially available from TORAY THIOKOL CO., LTD. 
The sulfur-modified epoxy resins employed in the present invention have 
better adhesiveness and better chemical resistance than ordinary epoxy 
resins. Further, since they have specific polysulfide skeleton structures, 
they have good flexibility and impact resistance. Still further, they are 
excellent in adhesiveness with metals and inorganic substances (salts of 
metals). Still further, they exhibit strong adhesiveness with wet 
surfaces. 
Curing Agent 
The curing agent used in the present invention is a curing agent for the 
above-described sulfur-modified epoxy resin. 
As such a curing agent, amines and acid anhydrides are mainly employed. 
As the curing agent which is an amine, any of room temperature-curing type, 
medium temperature-curing type and high temperature-curing type may be 
employed. The curing agent may be a primary amine, secondary amine or a 
tertiary amine. Specific examples of the amine-based curing agents include 
aliphatic polyamines such as triethylenetetramine; polyamides such as 
condensed products of a dimer acid and a polyethylene polyamine; and 
aromatic polyamines such as m-xylenediamine. Modified polyamines such as 
adducts of a polyamine and phenylglycidylether or ethyleneoxide are 
preferred since their volatilities and toxicities are small. 
On the other hand, examples of the curing agent which is an acid anhydride 
include phthalic anhydride, hexahydrophthalic anhydride and chlorendic 
acid. 
Composition 
The composition for forming the water-permeable material according to the 
present invention comprises the above-described aggregate grains, the 
sulfur-modified epoxy resin and the curing agent. In this composition, the 
mixing ratio (A/B) of the aggregate grains (A) to the sulfur-modified 
epoxy resin (B) is adjusted to 100/1-100/25, preferably 100/2-100/15 by 
volume. If the content of the sulfur-modified epoxy resin is less than the 
above-mentioned range, the adhesion among the aggregate grains is reduced. 
On the other hand, if the content of the sulfur-modified epoxy resin is 
more than the above-mentioned range, the water-permeable material is 
clogged with the resin, so that the water permeability is reduced. 
The composition according to the present invention may comprise other 
components in addition to the above-mentioned indispensable components. 
Examples of such other components include resins other than the 
sulfur-modified epoxy resins, pigments, bulk fillers, reinforcing 
materials and other components. 
Examples of the resins other than the sulfur-modified epoxy resin include 
resins miscible with the sulfur-modified epoxy resins such as excess epoxy 
resins other than the sulfur-modified epoxy resins, which were added for 
synthesizing the sulfur-modified epoxy resins, alkyd resins, 
polyvinylformal resins, phenol resins, polyvinylacetal resins, urea 
resins, melamine resins and various aliphatic acids. Epoxy resins which 
are the same as or different from the epoxy resin that is the starting 
material for synthesizing the sulfur-modified epoxy resin may be added to 
the composition. 
Examples of the pigment include inorganic fine powders such as talc, 
calcium carbonate and kaolin; organic fine powders such as polystyrene 
resins and polyethylene resins; organic and inorganic coloring pigments 
such as soil, metal powders, lakes, pigment colors and carbon; and soluble 
dyes such as triphenylmethane-based, anthraquinone-based, and 
naphthol-based dyes. 
Examples of the bulk fillers and the reinforcing materials include 
inorganic fine powders such as cement powder, silica fume, mica, glass 
flake and asbestos; fine aggregate; gravel; and fibrous materials such as 
polyolefin fibers, carbon fibers and glass fibers. 
An example of the above-mentioned "other components" is the epoxy monomer 
which is added in excess when synthesizing the sulfur-modified epoxy 
resin. 
To promote the weatherability of the water-permeable material, a weather 
stabilizer such as an U.V. absorber may be added to the composition 
according to the present invention. It should be noted, however, that when 
a pigment is incorporated in the composition, the pigment can promote the 
weatherability even if a weather stabilizer is not contained. 
Colored powder made of the same material as the aggregate grains may be 
added to the composition according to the present invention. For example, 
fine powder (average particle size of not more than 500 .mu.m) of colored 
ceramic balls may be incorporated. Such fine powder is incorporated in the 
resin component which binds the aggregate grains and may color the resin 
regions in the water-permeable materials. 
Process for Producing Water-permeable Material 
The water-permeable material made from the above-described composition is 
used for forming those for which water permeability is required, such as 
footpaths, roadways, plazas, dry riverbeds, banks, roofs of buildings, 
parking spaces, swimming pool sides and the like. The water-permeable 
material may be applied in situ at the place under construction or may 
preliminarily be shaped in the form of plate or block. 
When the water-permeable material is produced in situ using the 
above-described composition, the application surface on which the 
water-permeable material is to be formed is first provided. The 
application surface may be a vertical surface, slant surface or a 
horizontal surface. The material constituting the application surface may 
preferably be hard soil, stone or concrete. In cases where the application 
surface is a water-impermeable surface which is not so irregular or is 
made of a water-permeable concrete or a water-permeable asphalt laminated 
on a cut stone having a large irregularity, it is preferred to apply a 
primer on the application surface in order to promote the adhesion between 
the application surface and the water-permeable material and to prevent 
deformation of the water-permeable material. 
On the above-mentioned application surface, the composition for forming the 
water-permeable material according to the present invention is placed. In 
this step, pressure or vibration is given to the composition so that the 
composition is uniformly spread on the entire application surface. 
Thereafter, the surface of the composition is uniformly finished by using 
a metal trowel or the like. The thickness of the applied composition is 
not less than 3 mm, preferably 5-100 mm, although not restricted. Such a 
method is known in the art. 
The composition thus applied on the application surface is cured by leaving 
the composition to stand at room temperature or by heating the 
composition, thereby the water-permeable material is formed. 
In cases where the water-permeable material is produced in situ on the 
application surface, the weather is not critical as long as it is not so 
harsh as to give physical deformation in the surface of the applied 
composition. Depending on the weather, however, it is preferred to control 
the curing rate by adding a curing rate-controller such as a curing 
promoter or a retarder. 
On the other hand, in cases where the water-permeable material is shaped 
into plate or block, a molding frame is first provided. The molding frame 
may be made of, for example, an acrylic resin. The size of the molding 
frame may preferably be 0.5-10.sup.-4 m.sup.3. 
The above-described composition is then poured into the above-mentioned 
molding frame and is uniformly spread by giving pressure or vibration, 
followed by curing the composition. After curing, the molding frame is 
removed to obtain a water-permeable material in the form of a plate or 
block. The thus obtained water-permeable materials are laid on the 
above-mentioned application surface. 
In some cases, it may be preferred to add various solvents to the 
composition in order to promote the moldability of the composition and to 
promote the performance of the water-permeable material. Examples of the 
solvents to be added include ketones such as methylethyl ketone; esters 
such as ethyl acetate; chlorinated hydrocarbons such as 
1,2-dichloroethane; aromatic solvents such as toluene; and ethers such as 
diethylether. In cases where the evaporation of the solvent or in cases 
where it is desired to modify the performance of the water-permeable 
material, various reactive diluents suited for the particular purpose may 
be added. An example of the reactive diluent is an epoxy compound having 
one or more reactive epoxy groups in one molecule. 
Method for Applying Water-permeable Material Using Water 
The problems in the conventional application method are described above. 
When the water-permeable composition according to the present invention is 
used, water may be used in place of the organic solvent such as a thinner, 
when the composition for forming the water-permeable material, which 
contains the resin and the aggregate, is applied using a trowel or a 
finisher. 
The water is used such that the water exists at the interface between the 
surface of the trowel or the finishing surface of the finisher and the 
resin (covering the surface of the aggregate). More particularly, water is 
attached to the surface of the trowel or the finishing surface by 
supplying the water by an appropriate method (application, immersion, 
sprinkling and spraying) or the water is sprinkled to the surface of the 
aggregate. 
By using water, the friction between the water-permeable material (or the 
surface of the resin liquid attached to the aggregate) and the surface of 
the trowel or the finishing surface of the machine is drastically 
decreased, so that the resin liquid does not become sticky and the 
slipperiness is drastically improved. Further, by virtue of the good 
slipperiness of the aggregate mixture, the layer is well tightened so that 
the flatness of the surface is easily assured. 
Although the resin liquid gets sticky with time because of polymerization, 
since sliding resistance is not felt because of the existence of water, a 
resin liquid with high viscosity having good performance can be employed. 
Unlike a thinner, water is safe and does not elute or dissolve the resin, 
so that voids are not formed in the applied layer of the water-permeable 
material and troubles of contamination due to the delay of curing can be 
avoided. 
As the water, clean water, tapped water, rain water, river water and the 
like may be employed. Even if the water is little turbid due to soil or 
inorganic materials, it does not matter. Even if a compound which does not 
adversely affect the used resin liquid, such as a surfactant or a water 
soluble organic compound such as alcohols or celluloses is contained in 
the water, it does not matter. 
The amount of the water to be used is not restricted because the material 
to be applied is water-permeable, so that excess water is flowed out. 
However, the condition under which the resin contacts water during the 
curing reaction, such as the case where the resin is immersed in water or 
the curing reaction proceeds under rain for a long time, should be 
avoided. 
Advantageous Features of Water-permeable Material and Method for Applying 
the Same 
The water-permeable material made from the composition for forming the 
water-permeable material according to the present invention has the 
following advantageous features: 
(i) Since the sulfur-modified epoxy resin is used as the resin component, 
the flexibility and elongation of the resin are large, so that the 
material well follows deformation. Therefore, cracks are hardly formed, so 
that it is not necessary to frequently cut joints during the application 
operation. 
(ii) Ease of application is excellent. For example, the composition can be 
applied even if it rains. This is because that the polysulfide-modified 
epoxy resin is contained as the resin component, so that the curing rate 
is hardly decreased by water and deterioration of performance after curing 
hardly occurs. However, care should be taken that large external force or 
sustaining external force by water is not exerted during the resin is not 
cured. 
(iii) Even if the material contacts water, the adhesiveness is hardly 
reduced. The resin regions are hardly whitened and the material is not 
whitened by dew. 
(iv) The material has a good weatherability. Therefore, the material is 
hardly deteriorated (cracked or colored) with time by various conditions 
such as weather. 
(v) The material has a good chemical resistance. Therefore, the material 
exhibits excellent resistance to various food solutions, acidic rain, 
sewage and the like. 
(vi) By making water to exist on the surface of the trowel, finishing 
surface of the finisher and/or on the water-permeable material during the 
application operation, the operation efficiency is largely promoted and a 
material with high performance is obtained.

The present invention will now be described in more detail by way of 
examples. 
EXAMPLES 
Examples 1-3, Comparative Example 1 
Resin compositions having the compositions shown in Table 1 were prepared. 
In Table 1, "FLEP"-60 is a sulfur-modified epoxy resin (viscosity: 200 
poise (25.degree. C.), sulfur content: 11.2 wt %) commercially available 
from TORAY THIOKOL, "DAITOCRAL" X 2392 is a modified polyamine curing 
agent for epoxy resins commercially available from DAITO SANGYO, 
"FUJICURE" #5420 is a modified polyamine curing agent for epoxy resins 
commercially available from FUJI KASEI, and "ARALDAITO" XAC5009 and B-1968 
are an epoxy resin (viscosity: 19.6 poise (25.degree. C.)) and a curing 
agent for the epoxy resin, respectively, commercially available from 
NIPPON CIBA GEIGY. 
Each of the obtained resin compositions was mixed with green ceramic balls 
having an average particle size of 2 mm (commercially available from 
SHIBATA TOKI, maximum diameter: 3 mm) such that the entire surfaces of the 
balls are wetted. The mixing ratio of the resin composition (A) to the 
ceramic balls (B) was A:B=6:100 by weight. By this operation, compositions 
for forming water-permeable material were obtained. 
TABLE 1 
__________________________________________________________________________ 
Main Component Curing Viscosity 
Resin Diluent 
Agent Solvent (poise) 
__________________________________________________________________________ 
Example 1 
FLEP-60 -- DAITOCRAL 
Xylene 211 
(100) X2392(28) 
(2) 
Example 2 
FLEP-60 Phenylglycidyl- 
FUJICURE 
-- 46 
(87) ether (13) 
#5420 (30) 
Example 3 
FLEP-60 -- DAITOCRAL 
Xylene-methylene 
8 
(100) X2392(28) 
chloride Mixture* 
(25) 
Comparative 
ARALDAITO XA 
-- B-1968 -- 9 
Example 1 
C5009(100) (40) 
__________________________________________________________________________ 
*: Xylene/methylene chloride (w/w) = 1/1 
Values in parentheses indicate parts by weight. 
Each of the thus obtained compositions for forming water-permeable material 
was poured into a molding frame made of an acrylic resin sizing 12.8 
cm.times.7.8 cm.times.1.0 cm, and the composition was uniformly spread 
using a trowel. The compositions were left to stand until the next day to 
cure the resins. The cured products were removed from the molding frames 
to obtain water-permeable materials in the form of plate. 
The thus obtained water-permeable materials were left to stand at 
20.degree. C. for 7 days and then bending strengths and Charpy impact 
strengths were measured. The bending strengths were measured according to 
JIS-R-5201 before and after immersing the materials in 10% sulfuric acid. 
The materials were immersed in 10% sulfuric acid at room temperature for 1 
week. The Charpy impact strength was measured in accordance with 
JIS-K-7111-1977. The results are shown in Table 2. 
TABLE 2 
______________________________________ 
Bending Strength 
after Immersion in 
Bending Strength 
10% Sulfuric Acid 
(at maxium load) 
(at maximum load) 
Bending Bending Charpy Impact 
Strength Strain Strength 
Strain 
Strength 
(Kg/cm.sup.2) 
(mm) (Kg/cm.sup.2) 
(mm) (Kg .multidot. cm/cm.sup.2) 
______________________________________ 
Example 1 
94.3 1.30 91.0 1.27 0.98 
Example 2 
90.2 1.15 -- -- 0.84 
Example 3 
68.2 2.58 -- -- 1.58 
Comparative 
86.8 0.40 76.8 0.33 0.76 
Example 1 
______________________________________ 
As is apparent from Table 2, the water-permeable materials obtained in the 
examples of the present invention have good bending strengths, impact 
strengths and resistances to acid. It should be noted that the strains of 
the bending strengths of the materials according to the examples are 
larger than that of the material according to the comparative example. 
This shows that the water-permeable materials according to the present 
invention are flexible and are resistant to cracking, breaking and 
chipping. 
Examples 4-7, Comparative Example 2 
Resin compositions having the compositions shown in Table 3 were prepared. 
TABLE 3 
__________________________________________________________________________ 
Amount of 
Main Component Curing Added Water 
Resin Diluent 
Agent Solvent 
Wt % 
__________________________________________________________________________ 
Example 4 
FLEP-60 Phenylglycidyl- 
FUJICURE 
Xylene 
0 
(90) ether (10) 
#5420 (29.3) 
(6.8) 
Example 5 
FLEP-60 Phenylglycidyl- 
FUJICURE 
Xylene 
10 
(90) ether (10) 
#5420 (29.3) 
(6.8) 
Example 6 
FLEP-60 Phenylglycidyl- 
DAITOCRAL 
-- 0 
(90) ether (10) 
x2392(29) 
Example 7 
FLEP-60 Phenylglycidyl- 
DAITOCRAL 
-- 10 
(90) ether (10) 
x2392(29) 
Comparative 
ARALDAITO XA 
-- B-1968 -- 10 
Example 2 
C5009(100) (40) 
__________________________________________________________________________ 
Values in parentheses indicate parts by weight. 
Each component shown in Table 3 is the same as that shown in Table 1. 
Each of these resin compositions was mixed with the ceramic balls used in 
Examples 1-3. To the compositions according to Examples 5 and 7, and 
Comparative Example 2, water was further added. By this operation, 
compositions for forming water-permeable material were obtained. The 
amount of the added ceramic balls was the same as in Examples 1-3. 
Each of the thus obtained compositions for forming water-permeable material 
were poured into the molding frame used in Examples 1-3 and the 
compositions were left to stand for 24 hours to cure the resins. The cured 
products were removed from the molding frames to obtain water-permeable 
materials in the form of plate. 
The obtained water-permeable materials were tested for the bending strength 
as in Examples 1-3. The results are shown in Table 4. 
TABLE 4 
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Bending Strength 
after Immersion in 
Bending Strength 
10% Sulfuric Acid 
(at maxium load) 
(at maximum load) 
Bending Bending 
Strength Strain Strength 
Strain 
(Kg/cm.sup.2) 
(mm) (Kg/cm.sup.2) 
(mm) 
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Example 4 95.6 1.07 83.5 1.00 
Example 5 89.6 0.90 91.1 1.07 
Example 6 66.4 2.67 73.3 1.87 
Example 7 75.6 1.33 78.1 1.50 
Comparative 
75.5 0.57 18.0 0.43 
Example 2 
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No differences in outer appearance were observed between the compositions 
according to the examples of the present invention to which water was 
added and the compositions according to the examples of the present 
invention to which water was not added. In contrast, in the material 
obtained in Comparative Example 2, resin regions were partly whitened and 
the resistance to acid was extremely poor. 
Examples 8 and 9 
In molding the compositions for forming water-permeable material according 
to Examples 1 and 2, water was used in place of a petroleum-based thinner 
in order to improve the slipperiness of the trowel and to make it easy to 
remove the ceramic balls attached to the trowel in the molding operation. 
Ease of handling of the trowel was the same as in the case wherein the 
thinner was used, and no whitening of the water-permeable material was 
observed after leaving the composition to stand for 1 week. From this, it 
was confirmed that the whitening phenomenon does not occur even if water 
is used. 
Example 10 
Using the resin liquids used in Example 2 (FLEP series, viscosity: 46 
poises) and in Comparative Example 1 (ARALDAITO series, viscosity: 9 
poise), and using the ceramic balls as aggregate, compositions for forming 
water-permeable material were prepared. The obtained compositions were 
applied on asphalt pavement to a thickness of the water-permeable material 
of 10 mm, and the application processes were compared. 
In the case of the composition according to Example 2 (FLEP series), water 
was used for wiping the trowel and water was sprinkled on the composition 
during finishing. In spite of the fact that the viscosity of the resin was 
as high as 46 poise, the trowel could be moved fluently and could be used 
easily. Further, the finished layer was well tightened and had good 
flatness. On the other hand, in case of the composition according to 
Comparative Example 1, a petroleum-based thinner was used for wiping the 
trowel. Although at the beginning, the ease of handling of the trowel was 
the same as mentioned above, the trowel got heavy to move with time in 
spite of the low viscosity as low as 9 poise, so that the thinner was 
frequently used. The whitening of the material was not observed in the 
material prepared by using the composition of Example 2. In contrast, the 
entire surface of the material prepared by using the composition of 
Comparative Example 1 was whitened by dew and its strength was decreased. 
INDUSTRIAL AVAILABILITY 
The water-permeable material according to the present invention excels in 
chemical resistance and water resistance, and cracks are hardly formed 
therein. The material is also resistant to acidic rain. Therefore, the 
water-permeable material according to the present invention may be widely 
used for creating amenity spaces in hot spring resorts, sea shores and 
swimming pools. 
Since water, not an organic solvent, is used in molding, the operation is 
preferable from the viewpoint of hygiene, and the efficiency of the 
application operation is high. In addition, the quality of the 
water-permeable material is also high. Therefore, wide use of the 
composition according to the present invention is expected.