JPH0474037B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing stretchable padding using latent crimpable fibers.

In general, a known method for producing padded cotton is to form a web of fibers with a large number of crimps using a card, perform processing such as needling, and then bond the fibers together. However, with this manufacturing method,
Since the fibers are adhesively fixed to other fibers at the crimped portion, the degree of freedom of the fibers is reduced, and it is not possible to obtain padded cotton with sufficient elasticity. Furthermore, when fibers with a higher number of crimps are used, the carding properties are significantly deteriorated due to entanglement of the fibers, and there are production problems in that the web becomes extremely non-uniform. Therefore, the padded cotton produced by this manufacturing method could be used for quilting, etc., which does not require much elasticity, but was unsuitable for use in clothing such as sportswear, in which the human body moves vigorously. Therefore, as a method of imparting elasticity to padded cotton, a method has been proposed in which an elastic thread made of polyurethane elastomer or the like is inserted into a fiber web. However, this manufacturing method also requires a device and process for inserting the elastic threads, and the resulting cotton filling has insufficient elasticity in areas where the elastic threads are not present, resulting in wrinkles and twitching. It was hot.

The present invention was carried out in order to eliminate these conventional drawbacks, and an object of the present invention is to provide a manufacturing method for obtaining padded cotton having uniform and good elasticity.

The present invention involves forming a short fiber web (hereinafter simply referred to as a web) containing latent crimp fibers, spraying an adhesive onto the web, and heating the web at a temperature at which the crimp of the latent crimp fibers does not fully develop. After drying the web, heat treatment is performed without applying tension to cause the latent crimpable fibers to develop crimp, causing the web to shrink.
The present invention relates to a method for producing stretchable padded cotton having a weight of 0.005 to 0.05 g/cm ³ .

The latent crimpable fibers used in the present invention include side-by-side composite fibers made of two-component polymers with different thermal behaviors, and fibers that are heat-set in a highly twisted state and then untwisted at a lower temperature. These include thermoplastic fibers that have been given a thermal history by this process, and fibers that have been given latent crimpability by disrupting the molecular arrangement on one side of the fiber, such as edge-crimped yarn (rubbed yarn). The elasticity of the padded cotton is
This is caused by the crimp of the fibers constituting the cotton padding, so it is thought that the greater the number of crimp fibers, the better the elasticity can be obtained. Therefore, it is desirable that the latent crimpable fibers also exhibit a significant increase in the number of crimp after the occurrence of crimp.

In the present invention, the web is formed by a card method or the like. The fibers that make up the web include
It is preferable that the latent crimp fibers are mixed in an amount of at least 30% by weight, preferably 50% by weight or more. If the amount of latent crimpable fibers mixed into the web is less than 30% by weight, it will not be possible to obtain filler cotton with sufficient elasticity. The greater the amount of latent crimp fibers mixed into the web, the better the elasticity of the resulting filler will be, so in order to obtain the best stretchability, it is best to make the web with only latent crimp fibers. Just form it. The fibers to be mixed with the latent crimping fibers in the web are preferably fibers with a large number of crimps as long as they do not impede carding properties or web uniformity. Although it is possible to use fibers with a small number of crimps, they are not preferred because they reduce the elasticity of the resulting cotton wadding. Note that since latent crimpable fibers are used, carding properties are good and a uniform web can be obtained with good productivity. After forming the web, treatments such as needling may be performed if necessary.

Next, an adhesive such as an acrylic resin emulsion is applied to the web using a spray. In order to give the padded cotton elasticity, elasticity in the thickness direction, and bulkiness, the bonding points must be distributed three-dimensionally, and bonding by a spray method is necessary. In addition to the spray method, there is also a method using thermally adhesive fibers in which bonding points are distributed three-dimensionally. The elastic fibers melt again and bond and fix the crimped portion of the latent crimpable fibers to other fibers, which may impede the elasticity.
For this reason, although thermally adhesive fibers can be used as an auxiliary bonding means in an adhesive spraying method, it is not desirable to use thermally adhesive fibers as the main bonding means.

After applying the adhesive by spraying, the web is dried to bond and fix the fibers. In this step, if the latent crimpable fibers are completely crimped by drying heat, the web will shrink unevenly, resulting in dimensional deformation and poor elasticity. Therefore, drying must be carried out at a temperature at which the latent crimp fibers do not fully develop their crimp. Note that even if latent crimp occurs partially before the heat treatment, it is sufficient that the degree of latent crimp does not impair stretchability.

After drying, a heat treatment such as heating or hot water treatment is performed to cause the latent crimpable fibers to crimp, thereby shrinking the web. In order to obtain a filling with good elasticity, the web should not be under tension during contraction. This is because when tension is applied to the web, the fibers are fixed in an elongated state in the tension direction and sufficient shrinkage does not occur, which significantly reduces the elasticity of the resulting padded cotton. The above-mentioned drying of the web and development of crimping of latent crimping fibers are as follows:
Although it is preferable to use separate dryers,
A single dryer may be used as long as it is capable of crimping the latent crimpable fibers after drying the web.

In addition, the apparent density of the resulting padded cotton is preferably 0.005 to 0.05 g/cm ³ from the relationship between heat retention and strength.
Particularly preferably 0.01 to 0.03 g/cm ³ .

As described above, according to the present invention, since latent crimpable fibers are used, web formation with cards etc. can be carried out with high productivity, and since a spray method is used as a fiber adhesion method, bulkiness and elasticity in the thickness direction can be achieved. Filled cotton is obtained. Furthermore, in the present invention, after bonding the fibers, heat treatment is performed without applying tension to cause the latent crimpable fibers to develop crimp and shrink the web. A large number of these particles are generated in the web, and as a result, it is possible to produce padded cotton that has uniform and good elasticity.

The padded cotton obtained by the manufacturing method of the present invention not only has good elasticity as described above, but also has good washing resistance because it has been adhesively treated by spraying, and can be used for sportswear that requires elasticity. It can be used for insulation materials such as futons and gloves, as well as fillings for cold-weather clothing.

EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited thereto. In addition, in the examples, the residual strain rate is used as a value indicating elasticity, but this is measured by a test method based on JISL-1080, and the test piece is
The residual elongation after stretching and returning to the original position is repeated 10 times is divided by the original length of the test piece.
The value is expressed as a percentage.

Example 1 50% by weight polyester fiber with a thickness of 3 denier, length of 51 mm, and number of crimp of 17 threads/inch, which was given latent crimp property by the edge crimp method, and polyester fiber with thickness of 3 denier, length of 51 mm, and crimp Using 50% by weight conduit gate type highly crimped polyester fibers with 17 threads/inch, crosslay card was used to achieve a fabric weight of 38g/m ²
A web was formed. Next, a polyacrylic acid ester emulsion was applied to both sides of this web by spraying and dried in a band dryer at 100°C or less. The basis weight of the web at this time was 44 g/m ² . After drying, the latent crimpable fibers were caused to shrink using a dryer heated to 170° C. without any tension being applied to the web, thereby causing the web to shrink. The number of crimps of the latent crimped fiber after crimping is 34.
The shrinkage rate of the web was 17% in the longitudinal direction and 23% in the width direction.

The fabric weight of the resulting padded cotton is 70g/m ² and the thickness is 7.
mm, and the apparent density was 0.01 g/cm ³ . In addition, the residual strain rate, which indicates the elasticity of the cotton filling, was 2.5% in the longitudinal direction and 1.5% in the width direction, indicating very good elasticity. Furthermore, even after dry cleaning, the residual strain of the padded cotton is 3.5% in the longitudinal direction.
Maintains good elasticity of 2.0% in the width direction,
It also had dry cleaning resistance.

Comparative Example A web with a basis weight of 38 g/m ² was formed using a crosslay card using 100% by weight of a conjugate type highly crimped polyester fiber with a thickness of 3 denier, a length of 51 mm, and a number of crimps of 17 threads/inch. . Next, in the same manner as in Example 1, polyacrylic acid emulsion was applied to both sides of this web by spraying.
Dry in a hair dryer at ℃. The basis weight of the web at this time was 44 g/m ² .

The residual strain rate of the filled cotton obtained in this way cannot be measured because the filled cotton cannot withstand repeated elongation of 40% in the longitudinal direction and is cut, and it is extremely elastic at 15% in the width direction. It showed a lack of sexuality.

Example 2 A polyester component with a melting point of 210°C and a shrinkage start temperature of 160°C and a polyester component with a melting point of 255°C and a shrinkage start temperature of 230°C, with a thickness of 4 denier and a length of 51 cm.
Using 100% by weight side-by-side composite fiber of mm, the fabric weight is 55g/
^A web of 10 mm thick was formed. Next, this web was subjected to needling treatment with a fiber rocker to obtain a felt-like web with a thickness of 4 mm. Polyacrylic acid ester emulsion was applied to both sides of this felt-like web by spraying and heated to 120°C.
It was dried. The basis weight of the web at this time was 63 g/m ² . After drying, the side-by-side composite fibers having latent crimpability were crimped using a heat shrinking machine heated to 170° C., thereby shrinking the web. The shrinkage rate of the web was 22% in the longitudinal direction and 38% in the width direction.

The fabric weight of the resulting padded cotton was 130g/m ² and the thickness was 6.
mm, and the apparent density was 0.022 g/cm ³ . Further, the residual strain rate was 1.5% in the longitudinal direction of the padded cotton and 1.0% in the width direction, indicating better elasticity than in Example 1 since the web was formed only from latent crimp fibers. Furthermore, the elasticity was improved by the needling treatment, making it possible to produce padded cotton suitable for use in sportswear and the like.

Claims (1)

[Claims] 1. A short fiber web containing latent crimpable fibers was formed, an adhesive was sprayed on the short fiber web, and the short fiber web was dried at a temperature at which the crimp of the latent crimpable fibers did not fully develop. After that, the latent crimpable fibers are subjected to heat treatment without applying tension, thereby causing the short fiber web to shrink.
Method for manufacturing cm ³ elastic padded cotton.