JPH04281051A - Knitted fabric excellent in dimensional stability - Google Patents

Abstract

PURPOSE:To provide the title knitted fabric dyeable with basic dye containing spun yarns blended with modacrylic fibers with the surface impregnated with a small amount of a solvent and also knittedly woven homogeneously. CONSTITUTION:The objective knitted fabric containing spun yarns blended with >=20wt.% of modacrylic fibers with the surface impregnated with 0.5-10wt.% of a solvent (pref. sulfolane) and also knittedly woven homogeneously using at a level accounting for >=50wt.% of the whole yarns used. It is preferable that said modacrylic fibers be obtained by immersing conventional acrylic fibers in a solvent diluted with e.g. water followed by drying at <=60 deg.C. Said fibers, when dried, may mildly stick; in that case, they are recommended to open before blending.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a knitted fabric having excellent dimensional stability.

0002

BACKGROUND OF THE INVENTION In order to improve the dimensional stability of knitted fabrics, it is possible to use blended yarns in which heat-fusible fibers are blended. Previously, as a heat-fusible fiber
In the publication, crystalline polypropylene (first component)
By spinning ethylene-vinyl acetate copolymer or its saponified product and polyethylene (second component) side-by-side or in a core-sheath type, the thermal adhesion between fibers and the thermal adhesion with other different materials can be improved. A thermoadhesive composite fiber is disclosed.

Regarding acrylic and acrylic fibers,
Acrylic heat-sealable fibers are still in the development stage because they are difficult to melt during spinning.

Furthermore, when the heat-fusible fiber of the above-mentioned Japanese Patent Publication No. 54-44773 is blended with acrylic fiber, the heat-fusible fiber is not dyed with the basic dye and remains white when dyeing the yarn. The drawback is that it significantly reduces value. Furthermore, since the fiber is a composite fiber of polypropylene and polyethylene, it is not easy to impart flame retardancy to the fiber.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a knitted fabric that can be dyed with basic dyes and has excellent dimensional stability.

[0006]

[Means for Solving the Problems] In order to achieve the above object, the present invention adopts the following configuration. That is, modified acrylic fibers impregnated with 0.5 to 10% by weight of solvent from the fiber surface (
This knitted fabric is made of spun yarn in which 20% or more of (thermally fusible acrylic fiber) is blended, 50% or more of the spun yarn is used, and the knitted fabric is substantially uniformly knitted.

[0007] The constituent elements of the present invention will be described below. The spun yarn used in the present invention removes the solvent from the fiber surface by 0.5 to 1
20% or more of modified acrylic fiber (heat-fusible acrylic fiber) impregnated with 0% by weight is blended. The acrylic fiber used in the spun yarn of the present invention is a general acrylic or acrylic fiber containing acrylonitrile as a main component (40% by weight or more). For example, commercially available ordinary acrylic fibers such as Cashmiron, Exlan, Bonnell, Bethlon, Toleron, and Kanekalon may be used. As the second comonomer, methyl acrylate, vinyl acetate, acrylamide, acrylic acid, vinyl chloride, vinylidene chloride, etc. can be used. Further, as the third monomer, sodium allylsulfonate, sodium methacrylsulfonate, sodium 2-acrylamide 2-methylpropanesulfonate, etc. can be used.

In the acrylic fiber of the present invention, the surface of the acrylic fiber is substantially impregnated with 0.5% by weight or more of a solvent (based on the weight of the fiber), and the surface of the acrylic fiber is plasticized by the solvent impregnated into the surface of the acrylic fiber. Heat fusion properties are developed. If the amount of impregnated solvent is less than 0.5% by weight, the thermal fusion effect will be low. The content is preferably 1% by weight or more, and particularly when a high thermal bonding strength (strength during untwisting) is required, the content is preferably 3% by weight or more. If the solvent is impregnated with 10% by weight or more, the stability with the spinning oil to be mixed becomes poor, resulting in scum or part of the oil separating, which is not preferable.

Next, a method for producing heat-fusible acrylic fibers used in the spun yarn of the present invention will be described. The polymerization method may be solution polymerization or suspension polymerization, and is not particularly limited. There are no particular problems with the spinning method, either wet or dry. The acrylic fibers used may be either spun dyed cotton or dyed acrylic fibers. The solvent used in the present invention may be a common organic solvent for acrylic, such as dimethyl sulfoxide, dimethyl acetamide, dimethyl formamide, sulfolane, ethylene carbonate, etc. Among them, sulfolane having a high boiling point is preferred, and a plurality of solvents may be used as a mixed solvent. The solvent is mixed with, for example, an aqueous solution or emulsion of a spinning oil to substantially uniformly adhere to the fibers. In order to attach a small amount of solvent (about 0.5%) to the fibers, there is a method of spraying the solvent directly and then thoroughly mixing the cotton, but it is also possible to dilute the solvent with a diluent that easily evaporates, such as water. Post-deposition is preferred. The method of attachment may be a dipping method or a spraying method. Although not particularly limited, the dipping method is preferable because it causes less spots of adhesion. In order to impregnate the fibers with the solvent and to dry the diluent, the solvent is applied and then dried. As drying progresses, the fibers swell due to the solvent on the fiber surface and are simultaneously impregnated with the solvent, but if the drying temperature is too high, the fibers will adhere to each other. If the drying temperature exceeds 80° C., adhesion will become significant, which is not preferable. The temperature is preferably 70°C or lower, preferably 60°C or lower, although the drying efficiency decreases. Although the heat-fusible fibers of the present invention may slightly stick together when dried, they may be used by opening them before blending. Next, spinning is performed, and general methods such as short fiber spinning, semi-straight wool spinning, straight wool spinning, air spinning, and bundle spinning may be used, but modified acrylic fibers and other fibers may be uniformly blended. is preferred. It is necessary to thoroughly mix the cotton by passing it through a cotton blending machine before putting it into the card. If the cotton is not mixed sufficiently, the heat-sealing effect will be uneven and cause unevenness in the product.

The blending ratio of the modified acrylic fibers used in the spun yarn of the present invention is 20% by weight or more, and the spun yarn is used to produce knitted fabrics. The knitting machines and looms to be set up may be ordinary ones.For example, in the case of knitting, the weave is selected appropriately so that warp knitting is alternately knitted, and in the case of weft knitting, the number of threads to be supplied is appropriately allocated, and in the case of woven fabrics, The warp and weft structures may be appropriately selected. The modified acrylic fiber blend yarn has a knitting ratio of 50% or more, preferably 70% or more, and is substantially uniformly knitted and woven. Interlaced weave ratio is 50
%, dimensional stability is not sufficient. The obtained knitted fabric is heat-treated in a tenter-type hot-air dryer at 100° C. or higher for 30 seconds or longer to undergo heat-fusion treatment. When the blending ratio of modified acrylic fibers is low, heat treatment is preferably performed at 110° C. or higher for 1 minute or longer in order to further strengthen the heat fusion bond.

[0011]

[Examples] The present invention will be specifically explained below with reference to Examples. In addition, "%" in the examples means "weight %". <Measurement of fiber strength and elongation> JIS L-1015, <
Measurement of strength and elongation of spun yarn> JIS L-1095, <
Measurement of dimensional stability of circular knitted fabric of spun yarn> JIS
L-1018 Drying shrinkage rate, <Measurement of dimensional stability of textiles> JIS L-104
2, <Flammability of knitted fabrics> JIS L-1091,
Each was conducted according to the following. The sample was processed once according to the washing test method using a household washing machine, and used as a sample for measurement.

Example Commercially available Kanebo acrylic (acrylonitrile 90% by weight)
, methyl acrylate 9.5% by weight, methacrylsulfonate sodium salt 0.5% by weight) 3d51mm and flame-retardant acrylic, Rufunene (acrylonitrile 60% by weight, vinylidene 39% by weight, methacrylsulfonate sodium salt 1% by weight) 3d51mm as acrylic fiber. used. 10g of acrylic fiber was immersed in 100ml of an aqueous solvent solution under the conditions shown in Table 1. After the solvent was applied to the fibers by the dipping method, the fibers were squeezed using a centrifugal dehydrator and dried using a hot air dryer under the conditions shown in Table 2. The obtained modified acrylic fibers were mixed with normal acrylic fibers at the blending ratio shown in Table 3 using a cotton blending machine, passed through a roller type drawing machine twice, roving was made using a flyer type roving machine, and then passed through a short spinning machine. Number of twists: 420 times/m
Blended with No. 25 single yarn, mixed with 540 twists/m to obtain No. 52 single yarn, and No. 52 single yarn was twisted with double twister to obtain No.
A double thread was obtained by threading 0 times/m. For knitting, we also prepared intertwisted twin yarns made of a blended yarn of modified acrylic fibers and a normal yarn. The strength of the obtained single yarn was measured using a Tensilon type tensile tester, and the results are shown in Table 3. Table 3 No. No. 2 (reference example) has a low amount of solvent attached to the modified acrylic fiber. No. 1 (reference example) has a low blending ratio. In Example 4 (Reference Example), the drying temperature of the modified acrylic fibers was too high and they stuck together, so normal spinning could not be performed. The No. 52 double yarn was used as the warp yarn, and the No. 25 single yarn was used as the weft yarn, making a plain weave with 120 yarns and 100 yarns for the warp and warp, respectively. The fabrics tested for flame retardancy are all made of acrylic material and the above-mentioned Rufunen 3.
d51mm was used. The blended yarn of modified acrylic fibers is a plain weave "Weave Fabric No. 1", which has regular pure acrylic yarn and one plain weave in each warp, and the blended yarn of modified acrylic fiber is a plain weave "fabric No. 1" with one regular pure acrylic yarn in each warp and warp. Earth No.
．． 2" was created. As a reference example, a "reference woven fabric" was created using the corresponding normal acrylic pure yarn. In addition, the circular knitted fabric is made using a regular 32-hole circular knitting machine for jersey, and the fabric is ``Knitted Fabric No. 1'', which uses a No. 52 intertwisted double yarn, and the No. 52 mixed yarn of modified acrylic fiber in each stitch. A knitted fabric “Knitted Fabric No. 2” was created using yarn and No. 52 intertwisted twin yarn. As a reference example, a "reference knitted fabric" was created using the corresponding normal acrylic pure yarn. The obtained knitted fabric was subjected to dry heat treatment at 110° C. for 3 minutes. Table 4 shows the dimensional stability test results of the obtained knitted fabric. Similarly, the vertical flammability test results of a circular knitted fabric using flame-retardant acrylic and a fabric knitted with modified acrylic fiber No. 52 twisted double yarn using a regular 32-neck circular knitting machine for jersey are still available. It exhibited excellent flame retardancy with a flame time of 2 seconds and a carbonization distance of 5 cm. The dimensional stability was excellent with almost no difference from "knitted fabric No. 1".

[0013]

[Table 1]

[0014]

[Table 2]

[0015]

[Table 3]

[0016]

[Table 4]

[0017]

[Effects of the Invention] The knitted fabric using the spun yarn blended with the modified acrylic fiber of the present invention exhibits excellent dimensional stability.

Claims (1)

[Claims] Claim 1: Consisting of a spun yarn in which 20% or more of modified acrylic fibers are impregnated with 0.5 to 10% by weight of a solvent from the fiber surface, 50% or more of the spun yarn is used, and the yarn is substantially uniform. A knitted fabric characterized by being mixed and woven.