WO2007060946A1

WO2007060946A1 - Acrylic shrinkable fiber and process for production thereof

Info

Publication number: WO2007060946A1
Application number: PCT/JP2006/323206
Authority: WO
Inventors: Masaaki Miyoshi; Sohei Nishida
Original assignee: Kaneka Corporation
Priority date: 2005-11-22
Filing date: 2006-11-21
Publication date: 2007-05-31

Abstract

The invention aims at providing an acrylic shrinkable fiber which retains a high shrinkage factor even after dyeing and little changes in shrinkage factor within the tentering temperature range of 110 to 130°C. This aim is attained by an acrylic shrinkable fiber which is obtained by spinning a spinning dope containing a mixture of an acrylonitrile copolymer with a copolymer containing at least 1% by weight of a monomer bearing a sulfonic acid group by a wet spinning process comprising a drying step wherein 2 to 20% relaxation and 1.5- to 2-fold stretching at 95 to 115°C are conducted successively either in the course of the drying step or after the drying step and which exhibits a dry-heat shrinkage factor of 15% or above in dry-heat treatment at 110°C for 5 minutes after the dyeing at 80°C or below and a difference of 10% or below between the dry-heat shrinkage factor observed in dry-heat treatment at 110°C for 5 minutes and that observed in dry-heat treatment at 130°C for 5 minutes.

Description

Specification

Method for producing acrylic shrink fiber

Technical field

[0001] The present invention relates to a dyeable acrylic high-shrinkable fiber having a high shrinkage rate even after dyeing, and a production method.

Background art

[0002] Acrylic synthetic fibers are widely used in the fields of hynoir, bore, seal, fleece and the like because of their soft feel and ease of handling. Among them, the shrink fiber is suitable for use as a portion corresponding to down hair of natural hair. When shrinking fibers are mixed with non-shrinking fibers for guard hair and pile processing is performed, only the shrinking fibers are shrunk, resulting in a clear step with the non-shrinking fibers. For this reason, shrink fibers are used in pile products such as mink type.

[0003] However, when the shrink fiber is dyed at a normal dyeing temperature of 90 ° C or higher, the shrink fiber shrinks at the time of dyeing, and the shrinkage becomes difficult in the pile caching process. Therefore, the original fiber colored in the spinning process has been used for piles and the like (Patent Document 1). When coloring in the spinning process, many product losses occur when switching from one color to another. For this reason, the production of small lots was inefficient, and it was not easy to produce piles with various hues where the hue of the shrink fibers was limited.

[0004] In recent years, acrylic short fibers have been developed that can be dyed in a warm bath at a low temperature of 80 ° C or lower and do not shrink much during dyeing (Patent Document 2). However, this acrylic short fiber had a slightly lower shrinkage at 110 ° C., which is slightly lower in dry heat shrinkage after dyeing than the shrinkable fiber colored in the spinning process.

[0005] On the other hand, when shrink fibers are used in piles, the fibers are shrunk in a tenter process in which an adhesive is attached to the back surface of the pile and dried. The temperature for shrinkage is often 110-130 ° C. However, the temperature inside the tenter varies depending on the location, and the heating time may not be constant. Therefore, it is desirable that the shrinkage rate is as constant as possible in a wide temperature range, particularly in a range of 110 ° C to 130 ° C. 110 If the difference in shrinkage between ° C and 130 ° C is large, the difference between the shrinkable fiber and the non-shrinkable fiber may not be constant throughout the pile due to temperature variation inside the tenter.

[0006] As described above, when acrylic short fibers dyed in a warm bath are used, the level difference becomes unclear due to the low shrinkage, and the change in shrinkage from 110 ° C to 130 ° C is large. There was a drawback that it was difficult to obtain a stepped noise of a certain size over the entire pile. Patent Document 1: JP-A-60-21978

Patent Document 2: WO2002Z053825 Publication

Disclosure of the invention

Problems to be solved by the invention

[0007] An object of the present invention is to provide a pile in which a step difference between a guard hair and a down hair is clear and constant even when using a pile processing machine using an acrylic fiber that can be dyed in a warm bath and having a variation in temperature. It is an object to provide an acrylic fiber that can be used for manufacturing a fiber or a method for manufacturing the same.

Means for solving the problem

[0008] The present inventors have found that the above-mentioned object has a shrinkage ratio of 15% or more when heated at 110 ° C for 5 minutes after dyeing, and a shrinkage ratio of 130% when heated at 110 ° C for 5 minutes. Difference in shrinkage when heated at 5 ° C for 5 minutes is 10% or less, maintains high shrinkage even after dyeing, and dry heat shrinkage at a temperature range of 110 to 130 ° C in the tentering temperature range It has been found that this is achieved by acrylic shrink fibers with little change in

In addition, the present inventors have maintained a high shrinkage ratio after dyeing acrylic shrink fibers, and in order to reduce the difference in shrinkage ratio between 110 ° C and 130 ° C, the drying process during wet spinning. It was found that the relaxation at this point and subsequent dry heat drawing conditions are important. Specifically, in the fiber production method, the film is drawn in a bath after nozzle spinning (drawing ratio is usually 1.5 to 8 times) and then dried (drying temperature is usually 120 ° C to 160 ° C). During the drying or after drying, it was relaxed by 2 to 20%, and then stretched by 1.5 to 2 times at 95 to 115 ° C., it was found that the shrinkage ratio of the present invention was obtained. The relaxation during drying may be either dry heat or wet heat. By relaxing during or after drying, the change in shrinkage from 110 ° C to 130 ° C after dyeing can be reduced. In order to obtain a clear pile with a step, % Or more is necessary, but such a shrinkage rate is achieved by the above-described stretching temperature, stretching ratio, and the like.

[0009] Also, as the fibers capable of dyeing at 80 ° C following a hot bath, and acrylonitrile 40-80 by weight percent and 0-5 percent by weight halogen-containing monomer 20 to 60 weight ^_0/0 and sulfonic acid-containing monomer Polymer (A) Polymer comprising 70 to 99% by weight, 5 to 70% by weight of acrylonitrile and 29 to 94% by weight of other copolymerizable monomers and 1 to 40% by weight of sulfonic acid-containing monomer (B ) A fiber made from a polymerization composition mixed with 1 to 30 parts by weight is preferred. The invention's effect

[0010] The acrylic shrinkable fiber of the present invention can be easily dyed at a low temperature by an ordinary dyeing method. In addition, it retains a high shrinkage rate even after dyeing, and there is little change in the shrinkage rate at 110 to 130 ° C. For this reason, it is possible to easily produce a mink type pile having various hues and having a uniform step between the guard hair and the down hair over the entire pile even if the tentering temperature varies.

BEST MODE FOR CARRYING OUT THE INVENTION

[0011] acrylonitrile copolymer used in the present invention are acrylonitrile from 40 to 80 wt% and Nono androgenic containing monomer 20-60 wt ^_0/0 and sulfonic acid-containing monomer 0 to 5 wt ^_0/0 become more polymer ( A) Polymer composed of 70 to 99% by weight, acrylonitrile 5 to 70% by weight and other copolymerizable monomers 29 to 94% by weight and sulfonic acid-containing monomer 1 to 40% by weight (B) 1 to 30% by weight %, Preferably from a polymerized composition mixed.

[0012] In the polymer (A) of the present invention, acrylonitrile is preferably used in an amount of 40 to 80% by weight. If it is 40% by weight or less, the heat resistance is lowered and the fibers are likely to be fused in the fiber production process, and if it is 80% by weight or more, the shrinkage at a dry heat of 110 ° C may be lowered. Examples of the halogen-containing monomer used in the polymer (A) of the present invention include halogenated vinyls such as salted vinyl, vinylidene chloride, vinyl bromide, vinylidene bromide and the like, Rogenbibiurydens and the like. These can be used alone or in combination of two or more. This halogen-containing monomer can be used in the polymer (A) in an amount of 20 to 60% by weight. If it exceeds 60% by weight, the hydrophobicity tends to be high and sufficient dyeability cannot be obtained. Examples of sulfonic acid-containing monomers that may be used in the polymer (A) of the present invention , Aryl sulfonic acid, methallyl sulfonic acid, styrene sulfonic acid, isoprene sulfonic acid,

2 Acrylamide 2-methylpropanesulfonic acid or metal salts and amine salts thereof. These can be used alone or in admixture of two or more. In the polymer (A) of the present invention, the content of the sulfonic acid-containing monomer is preferably 0 to 5% by weight. If it exceeds 5% by weight, voids stick to the fiber and the strength decreases.

[0013] In the polymer (B) of the present invention, it is preferable to use 5-70% by weight of acrylonitrile. If it is less than 5% by weight, fiber fusion occurs due to a decrease in heat resistance, and if it exceeds 70% by weight immediately, the heat resistance becomes high and sufficient shrinkage may not be obtained.

[0014] Examples of other copolymerizable monomers used in the polymer (B) of the present invention include allylic acid, methacrylic acid and lower alkyl esters thereof, and N or N, N alkyl substituted aminoalkyl esters. Glycidyl esters, acrylamide, methacrylamide, and their N or N, N-alkyl-substituted products, carboxyl group-containing vinyl monomers typified by acrylic acid, methacrylic acid, itaconic acid, etc., and their sodium, strength or Cationic bull monomers such as ammonia salts, quaternized aminoalkyl esters of acrylic acid and methacrylic acid, or beryl group-containing lower alkyl Ether, Bul group-containing lower carboxylic acid ester represented by butyl acetate, vinyl chloride, vinyl chloride vinyl chloride, vinyl chloride bromide And vinyl chlorides and chlorogenic vinylidenes such as styrene and vinylidene bromide, and styrene. These monomers can be used alone or in admixture of two or more. The content of other copolymerizable monomer components in the polymer) is preferably 29 to 94% by weight. If it is less than 29% by weight, the heat resistance becomes high and sufficient dyeability may not be obtained. In particular, from the viewpoint of dyeability, it is preferable to use an acrylate ester as another copolymerizable monomer. As the acrylate ester, methyl acrylate, ethyl acrylate, butyl acrylate, and the like are preferred. These monomers can be used alone or in combination of two or more.

[0015] Examples of the sulfonic acid-containing monomer used in the polymer) include allylic sulfonic acid, methallyl sulfonic acid, styrene sulfonic acid, isoprene sulfonic acid, 2-acrylamido 2-methylpropane sulfonic acid, or metal salts thereof. And amine salts I can get lost. These can be used alone or in admixture of two or more. In the polymer (B) of the present invention, the sulfonic acid-containing monomer component is preferably 1 to 40% by weight. If it exceeds 40% by weight, voids stick to the fiber and the strength decreases.

[0016] The acrylic shrink fiber of the present invention preferably contains 1.0% by weight or more of a sulfonic acid-containing monomer in order to improve dyeability.

[0017] The polymer (A) and the polymer) of the present invention use a known compound such as a peroxide compound, an azo compound, or various redox compounds as a polymerization initiator. It can be obtained by a general vinyl polymerization method such as turbid polymerization or solution polymerization.

[0018] The polymer (A) and the polymer) of the present invention can be used in organic solvents such as acetone, acetonitrile, dimethylformamide, dimethylacetamide, dimethyl sulfoxide, or inorganic solvents such as salt, zinc, nitric acid, and rhodan salts. Dissolve to make the spinning dope. Use inorganic and Z or organic pigments such as titanium oxide or coloring pigments, stabilizers effective in weathering resistance, etc. in this spinning solution as long as they do not interfere with spinning. Is also possible.

[0019] The mixing ratio of the polymer (A) and the polymer (B) of the present invention is preferably 70Z30 to 99Zl (weight). If the polymer (Β) is less than 1% by weight, sufficient dyeability cannot be obtained, and if it exceeds 30% by weight, void sticking occurs in the fiber, and strength and dyeability may be lowered.

[0020] A spinning stock solution in which a mixture of the polymer (Α) and the polymer (Β) is dissolved in a solvent is spun into a coagulation bath from a nozzle and stretched in the bath by a conventional method. The draw ratio is preferably in the range of 1.5 to 8 times. When the draw ratio in the bath exceeds 8 times, it is difficult to obtain a sufficient shrinkage ratio by drawing after drying. After stretching in a bath and washing with water, it is dried at 120 to 160 ° C. in a drying step. When the temperature is 120 ° C or lower, the densification of the fibers is not sufficient. When the temperature is 160 ° C or higher, the fibers are fused.

[0021] Relaxation of 2 to 20% may be performed during or after drying. The relaxation during drying may be either dry heat or wet heat. The relaxation temperature is preferably higher than the drying temperature. The relaxation temperature is preferably 3 ° C or higher, more preferably 5 ° C or higher, especially 8 ° C or higher than the drying temperature. When the drying temperature changes, the drying temperature refers to the drying temperature immediately before relaxation. The relaxation time is preferably within 30 seconds, preferably within 20 seconds, and particularly preferably within 15 seconds. Long at high temperature When the time is relaxed, the fiber is greatly shrunk, and it becomes difficult to obtain a fiber having a sufficient shrinkage rate even by the subsequent drawing treatment.

[0022] Thereafter, the film is stretched 1.5 to 2 times at 95 to 115 ° C. If the temperature is less than 95 ° C, the fiber is whitened by stretching. If the temperature is 115 ° C or more, the shrinkage rate decreases. In addition, it is difficult to obtain a shrinkage ratio of 15% or more at 110 ° C with an elongation of 1.5 times or less. With stretching of 2 times or more, the change in shrinkage ratio between 110 ° C and 130 ° C increases. Thereafter, crimping and cutting are performed, and dyed acrylic shrinkable fibers with a small change in shrinkage between 110 ° C and 130 ° C are obtained.

Example

[0023] The present invention will be described in more detail with reference to examples below, but the present invention is not limited to these examples. Prior to describing the examples, the evaluation method will be described.

[0024] (Dyeing shrinkage)

The dye shrinkage rate is an index of how much the fiber shrinks due to dyeing. The length L of the fiber after treating the fiber of length Lo in a water bath at a predetermined temperature for 60 minutes was measured, and the dyeing shrinkage was obtained from the following formula.

Dye shrinkage (%) = ((Lo-L) / Lo) X 100

[0025] (Shrinkage after dyeing)

The shrinkage after dyeing is an index of how much the dyed fiber can shrink in the tenter process. The fiber of length Ldo after dyeing was treated for 5 minutes at 110, 130 ° C using a soaking oven, the fiber length Ld was measured, and the shrinkage rate after dyeing was determined from the following formula.

Shrinkage after staining (%) = ((Ldo-Ld) / Ldo) X 100

[0026] (70 ° C staining relative saturation value)

The 70 ° C dyeing relative saturation value is an indicator of the dyeing ability of the fiber. The fiber was dyed with malachite green at a concentration of 2.5% omf at 70 ° C for 60 minutes to determine the saturation dyeing amount, and the relative saturation value was determined from the saturation dyeing amount. The saturated dyeing amount and the relative saturation value were obtained from the following formula.

Saturated dyeing amount = ((Ao— A) ZAo) X 2.5)

A: Absorbance of dyeing bath after dyeing (618nm)

Ao: Absorbance of dye bath before dyeing (618nm) Relative saturation value = saturation dyeing amount X 400/463

[0027] (Example 1)

As shown in Table 1, acrylonitrile (AN) Z butyl chloride (VC1) Z sodium styrene sulfonate (3S) = 50Z49. 5 / 0.5 acrylic copolymer (A1) and ANZ methyl acrylate (MA ) Copolymer (B1) consisting of Z2-acrylamide-sodium 2-methylpropanesulfonate (SAM) = 30Z40Z30 is mixed in a ratio of (Al) / (Bl) = 95/5 and dissolved in acetone. A spinning dope was prepared so that the concentration was 28%. This spinning dope is spun into a coagulation bath of acetone Z water = 30Z70, 25 ° C through a nozzle with a hole shape of perfect circle, diameter 0.08mm, and number of holes 10,000, and stretched 3 times while washing with water. After drying at 130 ° C for 8 minutes, 5% relaxation was performed at 140 ° C for 10 seconds. Furthermore, it was stretched 1.6 times at a dry heat of 110 ° C, then crimped by a stuffing box, cut to obtain an acrylic shrink fiber having a length of 4 dtex and a cut length of 32 mm. Table 1 shows the measurement results of the 70 ° C dyeing relative saturation value of this fiber and the dry heat shrinkage at 110 ° C and 130 ° C after dyeing at 70 ° C.

[0028] [Table 1]

[0029] (Example 2)

As shown in Table 1, acrylic copolymer (A2) consisting of ANZ vinylidene chloride (VD) Z3S = 52Z47Z1 and copolymer (B1) consisting of ANZMAZSAM = 30Z40Z30 (A2) / (Bl) = 95Z5 The spinning solution was prepared so that the polymer concentration was 28% by mixing at a ratio and dissolving in acetone. This spinning dope is spun into a coagulation bath of acetone Z water = 30Z70, 25 ° C through a nozzle with a hole shape of perfect circle, diameter of 0.08mm, and number of holes of 10,000, and doubled while washing with water. After drying at 130 ° C for 8 minutes, 3% relaxation was performed at 145 ° C for 7 seconds. Further, the film was stretched 1.7 times at 105 ° C with dry heat, then crimped with a stuffing box, cut to obtain an acrylic shrink fiber with 4 dtex and a cut length of 32 mm. Table 1 shows the measurement results of the 70 ° C dyeing relative saturation value of this fiber and the dry heat shrinkage at 110 ° C and 130 ° C after dyeing at 70 ° C.

[0030] (Example 3)

As shown in Table 1, ANZVDZSAM = 56Z42Z2 acrylic copolymer (A3) in dimethylformamide (DMF) solution (polymer concentration 26%) and ANZMAZSAM = 40 Z35Z25 copolymer in DMF ( A polymer stock solution of 26%) was mixed at a ratio of (A3) / (B2) = 90Z10 to prepare a spinning dope. DMFZ water = 60,40, 15 through a nozzle with a hole shape of 0.08 mm and a hole diameter of 10,000 mm. It was spun into a coagulation bath of C, stretched 4 times while washing with water, dried at 130 ° C for 8 minutes, and then relaxed by 10% at 145 ° C for 7 seconds. Furthermore, it was stretched 1.7 times at a dry heat of 110 ° C, then crimped by a stuffing box, and after cutting, 4dtex and a cut length of 32mm were obtained. Table 1 shows the measurement results of the relative saturation value of this fiber at 70 ° C dyeing and the dry heat shrinkage at 110 ° C and 130 ° C after dyeing at 70 ° C.

[Example 4]

As shown in Table 1, acrylic copolymer (A1) consisting of ANZVC1Z3S = 50Z49. 5 / 0.5 and copolymer (B3) consisting of ANZMAZSAM = 40Z50Z10 at a ratio of (Al) / (B3) = 85Z15 The mixture was dissolved in acetone to prepare a spinning dope so that the polymer concentration was 28%. This spinning dope was spun into a coagulation bath of acetone Z water = 30Z70, 25 ° C through a nozzle with a hole shape of perfect circle, diameter 0.08mm, and number of holes 10,000, and washed with water. The film was stretched twice, dried at 130 ° C for 8 minutes, and then relaxed by 4% at 145 ° C for 10 seconds. Furthermore, the film was stretched 1.6 times at 105 ° C with dry heat, then crimped with a stuffing box, and after crimping, an acrylic shrink fiber with 4dtex and a cut length of 32mm was obtained. Table 1 shows the measurement results of the 70 ° C dyeing relative saturation value and the dry heat shrinkage at 110 ° C and 130 ° C after dyeing at 78 ° C.

[Example 5]

As shown in Table 1, ANZVDZSAM = 56Z42Z2 acrylic copolymer (A3) in dimethylformamide (DMF) solution (polymer concentration 26%) and ANZMAZSAM = 42 Z50Z8 in DMF solution (B4) A polymer stock solution of 26%) was mixed at a ratio of (A3) / (B4) = 80Z20 to prepare a spinning dope. DMFZ water = 60,40, 15 through a nozzle with a perfect circular shape and a diameter of O.08 mm and a number of holes of 10,000. It was spun into a coagulation bath of C, stretched 5 times while washing with water, dried at 130 ° C for 8 minutes, and then relaxed by 12% at 145 ° C for 10 seconds. Further, the film was stretched 1.7 times at a dry heat of 115 ° C, then crimped by a stuffing box, cut to obtain an acrylic shrink fiber having a length of 4 dtex and a cut length of 32 mm. Table 1 shows the measurement results of the 70 ° C dyeing relative saturation value and the dry heat shrinkage at 110 ° C and 130 ° C after dyeing at 65 ° C.

[0033] (Comparative Example 1)

As shown in Table 1, acrylic copolymer (A1) consisting of ANZVC1Z3S = 50Z49. 5 / 0.5 and copolymer (B1) consisting of ANZMAZSAM = 30Z40Z30 at a ratio of (Al) Z (B1) = 95Z5 The mixture was dissolved in acetone to prepare a spinning dope so that the polymer concentration was 28%. This spinning dope is spun into a coagulation bath of acetone Z water = 30Z70, 25 ° C through a nozzle with a hole shape of perfect circle, diameter of 0.08mm and number of holes of 10,000, and stretched 3 times while washing with water. After drying at 130 ° C for 8 minutes, it was stretched 1.7 times at a dry heat of 110 ° C, then crimped by a stuffing box, and cut to obtain an acrylic shrink fiber with 4dtex and a cut length of 32mm. . Table 1 shows the measurement results of the relative saturation value of this fiber at 70 ° C dyeing and the dry heat shrinkage at 110 ° C and 130 ° C after dyeing at 70 ° C.

[0034] (Comparative Example 2)

As shown in Table 1, ANZVDZSAM = 56Z42Z2 acrylic copolymer (A3) Dimethylformamide (DMF) solution (polymer concentration 26%) and ANZMAZSAM = 42 Z50Z8 copolymer (B4) DMF solution (polymer concentration 26%) at a ratio of (A3) / (B4) = 80Z20 A spinning dope was prepared by mixing. DMFZ water = 60,40, 15 through a nozzle with a perfect circular shape and a diameter of O.08 mm and a number of holes of 10,000. It was spun into a coagulation bath of C, stretched 5 times while washing with water, dried at 130 ° C for 8 minutes, and then relaxed by 12% at 145 ° C for 10 seconds. Furthermore, it was stretched by 1.4 times at a dry heat of 115 ° C, then crimped by a stuffing box, cut to obtain an acrylic shrink fiber of 4 dtex and a cut length of 32 mm. Table 1 shows the measurement results of the relative saturation value of this fiber at 70 ° C dyeing and the dry heat shrinkage at 110 ° C and 130 ° C after dyeing at 70 ° C.

[0035] (Comparative Example 3)

As shown in Table 1, acrylic copolymer (A1) consisting of ANZVC1Z3S = 50Z49. 5 / 0.5 and copolymer (B5) consisting of ANZMAZSAM = 40Z45Z15 at a ratio of (A1) Z (B5) = 90Z10 The mixture was dissolved in acetone to prepare a spinning dope so that the polymer concentration was 28%. This spinning dope is spun into a coagulation bath of acetone Z water = 30Z70, 25 ° C through a nozzle with a hole shape of perfect circle, diameter 0.08mm, and number of holes 10,000, and stretched 4 times while washing with water. After drying at 130 ° C for 8 minutes, 10% relaxation was performed at 145 ° C for 8 seconds. Further, the film was stretched 1.7 times at 120 ° C with dry heat, then crimped by a stuffing box, and subjected to force to obtain an acrylic shrink fiber having a length of 4 dtex and a cut length of 32 mm. Table 1 shows the measurement results of the 70 ° C dyeing relative saturation value and the dry heat shrinkage at 110 ° C and 130 ° C after dyeing at 70 ° C.

[0036] (Comparative Example 4)

As shown in Table 1, ANZVDZSAM = 56Z42Z2 acrylic copolymer (A3) in dimethylformamide (DMF) solution (polymer concentration 26%) and ANZMAZSAM = 42 Z50Z8 copolymer (B4) in DMF solution ( A polymer stock solution of 26%) was mixed at a ratio of (A3) / (B4) = 60Z40 to prepare a spinning dope. DMFZ water = 60,40, 15 through a nozzle with a perfect circular shape and a diameter of O.08 mm and a number of holes of 10,000. It was spun into a coagulation bath of C, stretched 5 times while washing with water, dried at 130 ° C for 8 minutes, and then relaxed by 12% at 145 ° C for 10 seconds. Further, stretched 1.6 times at 110 ° C with dry heat, and then stuffy Crimping was applied by a box and after cutting, acrylic shrink fibers with 4dtex and a cut length of 32mm were obtained. Table 1 shows the measurement results of the relative saturation value of this fiber at 70 ° C dyeing and the dry heat shrinkage at 110 ° C and 130 ° C after dyeing at 70 ° C.

Industrial applicability

The acrylic shrinkable fiber of the present invention can be easily dyed by a usual dyeing method. In addition, a high shrinkage ratio is maintained even after dyeing, and there is little change in the shrinkage ratio at 110 to 130 ° C. For this reason, it is possible to easily produce mink type piles having various hues and having almost uniform steps between the guard hair and the down hair even if the tentering temperature is wide. In this way, it can be used especially in industrial fields such as nozzles.

Claims

The scope of the claims

[1] acrylonitrile 40-80 wt ^_0/0, acrylonitrile copolymerizable with the halogen-containing monomer one 20 to 60 weight ^_0/0, a sulfonic acid group-containing monomer 0 to 5% by weight strength becomes polymer (A) 70 to 99 the weight ^_0/0, acrylonitrile 5-70 ^_0/0 and other copolymerizable monomer 29-94 wt%, sulfonic acid group-containing monomer to 40% by weight strength becomes polymer (B) 1 to 30 wt% The mixed polymer composition is wet-spun and stretched in a bath, and then 2 to 20% relaxation is applied during or after drying, and further 1.5 to 2 times at 115 ° C or lower A method for producing stretched ateryl shrink fibers.

[2] The method for producing an acrylic shrinkable fiber according to [1], wherein the relaxation temperature is higher than the drying temperature.

[3] The method for producing an acrylic-based condensed fiber according to [2], wherein the relaxation temperature is 5 ° C or more higher than the drying temperature!

[4] acrylonitrile 40-80 wt ^_0/0, acrylonitrile copolymerizable with the halogen-containing monomer one 20 to 60 weight ^_0/0, a sulfonic acid group-containing monomer 0 to 5% by weight strength becomes polymer (A) 70 to 99 the weight ^_0/0, acrylonitrile 5-70 ^_0/0 and other copolymerizable monomer 29-94 wt%, sulfonic acid group-containing monomer to 40% by weight strength becomes polymer (B) 1 to 30 wt% The mixed polymer composition is wet-spun and stretched in a bath, and then 2 to 20% relaxation is applied during or after drying, and further 1.5 to 2 times at 115 ° C or lower Acrylic shrinkable fiber obtained by stretching.

5. The acrylic shrinkable fiber according to claim 3, wherein the relaxation temperature is higher than the drying temperature.

[6] The acrylic compressed fiber according to [2], wherein the relaxation temperature is 5 ° C or more higher than the drying temperature!

[7] Staining relative saturation value at 70 ° C is 0.5 or more, after dyeing at 80 ° C or less, dry heat shrinkage at 110 ° C for 5 minutes is 15% or more, and 110 ° C Acrylic shrinkable fiber that has a difference of 10% or less between the dry heat shrinkage when heated for 5 minutes at 130 ° C and the dry heat shrinkage when heated at 130 ° C for 5 minutes.