Napped fusible interlining cloth with adhesive powder on tips of nap

This invention provides a fusible interlining which comprises a base fabric having naps distributed thereon, the surface of tip portion of the naps is applied with heat adhesive synthetic resin powders. Particle size of the powders is preferably 80.mu. or less. A method for production thereof is also provided.

BACKGROUND OF THE INVENTION 
This invention relates to a heat fusible interlining cloth (hereinafter 
referred to as merely "fusible interlining") used mainly for shape making, 
shape retention and reinforcement of clothes, bags and the like and more 
particularly it relates to a fusible interlining which comprises a base 
fabric having thereon naps, the tip of naps being applied with heat 
adhesive synthetic resin fine powders and a method for making same. 
Fusible interlinings have been known which comprise a base fabric such as a 
woven fabric, a knitted fabric, a non-woven fabric or the like on the 
surface of which heat adhesive synthetic resin materials are allowed to 
exist. Especially, as fusible interlinings for clothes, there are widely 
used those which have adhesive resins applied in the form of dots in order 
to keep feelings of shell fabric such as softeness, air permeability, 
handling, appearance, etc. 
As these fusible interlinings having applied adhesive dots, there have been 
known those which are made by randomly scattering and fusion-bonding heat 
adhesive synthetic resin powders on a base fabric, by transfering and 
fusion-bonding small masses of the resin powders on a base fabric or by 
printing a paste containing the powders and drying them. 
In case of the above mentioned conventional fusible interlinings having 
adhesive resins in the form of random points which are made by scattering 
resin powders, it is difficult to uniformly distribute the powders on the 
surface of a base fabric and besides, when particle size of the powders is 
too fine, the powders sink into the base fabric, resulting in reduction of 
adhesion efficiency and deterioration of softeness and air permeability of 
the base fabric. Therefore, generally, powders having narrow particle size 
distribution within the range of 100-250.mu. in diameter are used. 
On the other hand, in case of those made by transferring or printing 
methods using engraved rollers, stencils, screens, etc., regular point 
distribution can be obtained, but when size of each dot is made small, the 
original pattern becomes unstable by clogging with resins. Therefore, the 
shapes of each dot are difficult to reduce to less than 0.1 mm in 
diameter. 
For the above reasons, the adhesive portions in the form of dots in the 
conventional fusible interlinings are relatively large and when they are 
subjected to hot press bonding to shell fabric, tendency of the adhesive 
to strike through the front and back sides of the bonded fabric increases 
with increase in bonding area and this may cause deterioration of handle. 
Especially, it is very difficult to obtain fusible interlinings effective 
for light weight shell fabric. 
SUMMARY OF THE INVENTION 
As a result of researches on the state of application or deposition of heat 
adhesive synthetic resin powders on base fabric in an attempt to solve the 
problems in the conventional fusible interlinings, it has been found that 
when the resin powders are applied to only nap portions distributed on the 
surface of a base fabric, excellent adhesion state can be obtained and 
this invention has been accomplished based on this finding.

DETAILED DESCRIPTION OF THE INVENTION 
The first invention has the gist in a fusible interlining cloth, 
characterized in that heat adhesive synthetic resin powders are applied 
mainly to the surface of tip portion of each nap distributed on a base 
fabric and one embodiment of the invention is that said heat adhesive 
synthetic resin powders have a particle size of 80.mu. or less and said 
powders are fusion-bonded to the surface of naps. 
The second invention is a method for making the fusible interlining of the 
first invention which comprises sprinkling charged powders of heat 
adhesive synthetic resin, suspension of said powders or fine particle 
emulsion of said resin onto a number of naps distributed on the fabric and 
standing on the fabric in electrostatic field, thereby to apply the resin 
powders mainly to the tip portions of the naps and then heating the fabric 
to fusion-bond the powders to the surface of the naps. 
The base fabrics having naps distributed thereon include knitted fabrics 
made from spun yarns, non-woven fabrics made from short staples and base 
fabrics made from filaments which are provided with naps by cutting 
surface filaments. In some case, it is preferred to subject the fabric to 
singeing or shearing in order to make even the fiber length of naps. 
As the powders of the heat adhesive synthetic resin powders, there may be 
used those of the known heat fusible resin materials, for example, 
synthetic resins and/or copolymer resins such as polyamide, polyester, 
polyethylene, polyurethane, polyvinyl chloride, ethylenevinyl acetate 
copolymer, mixtures thereof and mixtures of these resins and additives 
such as plasticizers if necessary. The particle size is 80.mu. or less in 
order that the powders can be applied stably to naps and good adhesion 
efficiency can be obtained. 
When the particle size of the resin powder is more than 80.mu., the powders 
are also applied onto the base portion of naps depending on sprinkling 
means and uniform distribution of the powders is difficult. Thus, volume 
of the adhesive portions is increased and penetration of powders into the 
fabric produces hard texture, which often results in deterioration of 
handle of fabrics. 
If the surface of resin powders are covered with a thin layer of water or a 
viscous solution at the time of sprinkling, they can be stably applied 
onto the surface of naps. On the other hand, when an electrostatic 
application means is employed, dry powders can also be stably applied. Of 
course, in this case, also the powders can be in the form of a dispersion 
in water and the like to cover the surface with water in order to obtain 
more excellent application state or an emulsion of fine particles of the 
resin may be sprinkled. The emulsion of fine particles are made into 
powders by removal of volatile matter. 
When the resin powders applied onto naps are fusion-bonded by heating, a 
stable fusible interlining from which the powders are difficult to remove 
by external force can be obtained. 
The fusible interlining of the first invention can be easily obtained by 
the production method of the second invention. 
That is, the method of the second invention is characterized in that 
charged heat adhesive synthetic resin powders or suspension thereof or 
emulsion of fine particles of said resin are sprinkled onto a number of 
naps which are distributed on the surface of a base fabric and in the 
state of being raised in a high voltage electrostatic field, thereby 
applying the powders mainly to the tip portion of naps and then the 
powders are fusion-bonded to the surface of naps by heating. 
In the above method for production of fusible interlinings, the base fabric 
and the heat adhesive synthetic resin powders are as stated above and the 
high voltage electrostatic field keeps normally a voltage gradient of 
60-120 KV in the zone of sprinkling and application of resin powders, 
wherein the resin powders are charged. 
The naps on the base fabric are in the state of being raises from the 
surface of the base fabric in said electrostatic field and the charged 
resin powders dispersed in the electrostatic field are selectively 
adsorbed onto the tip portion of the raised naps under good dispersion 
state to obtain relatively stable application state of the powders. These 
powders are heated by, e.g., infrared heating to such extent that the 
surface of the applied resin powders is fused, thereby to fusion-bond the 
powders. Thus, objective product is obtained. 
The drawing grammatically shows the enlarged cross-section of said product. 
That is, heat adhesive synthetic resin powders R of 80.mu. or less in 
particle size are fusion-bonded onto the tip portion of naps N which are 
distributed on the front side of a base fabric composed of yarns Y.sub.1 
and Y.sub.2 and which are longer among others. 
It is a matter of course that the method of this invention can be applied 
to a base fabric which is continuously moving. 
Since in the fusible interlining of this invention the heat adhesive 
synthetic resin powders are applied only to the tip portion of naps on the 
surface of base fabric, this interlining can be very effectively bonded by 
hot pressing to a fabric superposed thereon and the bonded portion is 
extremely small because they are bonded through the naps and hence 
softness and air permeability of the bonded fabric can be satisfactorily 
maintained. 
Furthermore, according to the method of this invention, it is very easy to 
uniformly distribute relatively small amount of resin powders on the 
surface of a base fabric and to apply them only to the tip portion of the 
naps. 
This invention is further illustrated by the following examples wherein 
"part" and "%" are by weight. 
EXAMPLE 1 
(1) Dispersion of resin powders 
A dispersion having a viscosity of 500 cp (20.degree. C.) which was 
prepared by mixing and stirring 100 parts of water, one part of sodium 
acrylate dispersant and 30 parts of polyamide resin powders (particle size 
80.mu. or less). 
(2) Sprinkling conditions 
An electrostatic coating apparatus provided with rotational spraying nozzle 
under operating conditions of rotation number of spray head: 50000-60000 
rpm and applied voltage DC: 120 KV. 
(3) Base fabric 
A plain weave fabric prepared with 65 ends and 58 picks per inch of 85 
count polyester 65% cotton 35% blended spun yarns. 
The base fabric was horizontally placed and the spray head was positioned 
at a distance of 40 cm above the base fabric, from which the dispersion 
was sprinkled. Then, the resin powders were dried and fusion-bonded by 
heating with an infrared heater to obtain an interlining with the resin 
applied only to the tip portion of naps in an amount of 6 g/m.sup.2. 
COMATIVE EXAMPLES 1-3 
The following three fusible interlinings were obtained by conventional 
method using the same base fabric and the same polyamide resin as used in 
Example 1. 
COMATIVE EXAMPLE 1 
An interlining of 6 g/m.sup.2 in application amount of resin which was 
produced by random scattering of the resin of 100-150.mu. in particle 
size. 
COMATIVE EXAMPLE 2 
An interlining of 7 g/m.sup.2 in resin application amount and 
1225/inch.sup.2 in dot density which was produced by application of the 
resin of 80.mu. or less in particle size by dot transfer method using an 
engraved roller. 
COMATIVE EXAMPLE 3 
An interlining of 8 g/m.sup.2 in resin application amount and 
900/inch.sup.2 in dot density which was produced by screen printing of 
dispersion containing the resin of 80.mu. or less in particle size. 
These interlinings are those which are practically used for application to 
light weight shell fabric. 
The interlinings of Example 1 and Comparative Examples 1-3 were subjected 
to bonding test under the following conditions. 
Shell fabric; Crepe de Chine of 100% silk (basis weight 45 g/m.sup.2) 
Bonding conditions; 140.degree. C., 0.3 kg/cm.sup.2, 10 seconds 
Thus bonded fabrics were subjected to measurement of bond strength (by 
peeling at 180.degree. ), visual examination of strike-through of resin to 
outer surface of the shell fabric, evaluation of handle with hands and 
measurement of strike-back of resin to the back side of the interlining 
under the following conditions and the results are shown in the following 
Table. 
Measurement of strike-back: On both sides of the interlining were 
superposed poplin fabrics prepared with 108 ends and 100 picks per inch of 
60 count polyester and cotton (65/35) blended spun yarns and these were 
bonded under the bonding conditions as mentioned above. Bond strength by 
180.degree. peeling of the cloth on the back side was measured. 
TABLE 
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Comparative Examples 
Example 1 
1 2 3 
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Bond strength 
150 150 180 150 
(g/inch) 
Strike- None Found Slightly 
Found 
through found occurred 
Strike-back 
0 10 15 30 
(g/inch) 
Handle Very Somewhat Soft Hard 
soft hard 
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That is, the fusible interlining of Example 1 was bonded to the light 
weight shell fabric in excellent bonding state while the conventional 
fusible interlinings had the problem of deterioration in properties of the 
bonded fabrics. 
EXAMPLE 2 
In accordance with the procedure of Example 1, a fusible interlining of 6 
g/m.sup.2 in resin application amount was produced using the same resin 
dispersion except that polyester resin powders (80.mu. or less) were used 
in place of polyamide resin powders, under the same electrostatic coating 
conditions and using as a base fabric a woven fabric prepared with 65 ends 
and 58 picks per inch of 80 count of 100% polynosic spun yarns. 
This fusible interlining was bonded to light weight shell fabric of crepe 
de Chine of 100% polyester (basis weight: 30 g/m.sup.2) by hot pressing. 
An extremely soft bonded fabric which cannot be obtained with the 
conventional fusible interlinings was obtained without any problems 
mentioned in Example 1. 
As explained hereabove, since the fusible interlining of this invention has 
heat adhesive synthetic resin powders applied to the tip portion of naps 
on a base fabric, bonding by hot pressing of it to a shell fabric can be 
easily and surely accomplished and useless penetration of resin into both 
shell fabric and base fabric of the interlining can be prevented. Thus, 
very soft bonded fabrics are obtained. This interlining is especially 
useful for application to light weight shell fabrics. 
Furthermore, according to the method for making the interlining of this 
invention, a relatively small amount of resin powders can be uniformly 
distributed on the surface of a base fabric and be applied to the tip 
portion of naps by utilizing electrostatic coating technique and fusible 
interlining of excellent quality can be produced efficiently.