WO2002053825A1

WO2002053825A1 - Acrylic short fiber and method of dyeing acrylic short fiber

Info

Publication number: WO2002053825A1
Application number: PCT/JP2001/011604
Authority: WO
Inventors: Kiyomiti Ninomiya
Original assignee: Kanebo, Limited; Kanebo Gohsen Limited
Priority date: 2000-12-28
Filing date: 2001-12-27
Publication date: 2002-07-11
Also published as: JPWO2002053825A1

Abstract

An acrylic short fiber capable of maintaining a high dry heat contractility; a method of manufacturing the acrylic short fiber by a dyeing method suitable for the dyeing of a small lot production of a wide variety of products, characterized in that the acrylic short fiber developing a dry heat contractility of 20 to 50% at 120 to 150 ° C is dyed with the cation dye in a warm bath at the temperature of 80 ° C or below, whereby, since the acrylic short fiber has target hue of color and fastness irrespective of the density of color and a high residual contractility, the short fiber can also be used in the application for being contracted under dry heat conditions.

Description

Description Method for dyeing acryl short fibers and acrylic short fibers

TECHNICAL FIELD The present invention relates to an acrylic short fiber and a method for dyeing an acrylic short fiber, which have a small decrease in dry heat shrinkage even by hot bath dyeing. Background art

Acrylic fibers can be dyed by adsorbing a cationic dye in a boiling bath, or by immersing the dye in an aqueous cationic dye solution immediately after being extruded from a spinneret in a wet spinning method to physically knead the dye between the fibers. There is a so-called soaking process.

The method of adsorbing cationic dyes on fibers in this boiling bath is more suitable for dyeing small lots of various products than the dyeing method, but the fibers shrink when heated at a high temperature. There is a disadvantage that the dry heat shrinkage of acryl raw cotton hardly remains. This means that it cannot be used for purposely shrinking under dry heat conditions.

On the other hand, in the soaking process, while the fiber structure of the cationic dye immediately after spinning is flexible, the dye is pushed into the inside of the fiber, so the dyeing speed is much higher, and it is suitable for mass production. The heat drawing applied before cutting into short fibers causes distortion in the fiber structure, and the short fibers after cutting have the advantage of remaining dry heat shrinkage.However, the dye is drawn between spinning and hot drawing. Since a special process of passing through a solution is required, there is a drawback that it is unsuitable for dyeing small lots of various varieties.

An object of the present invention is to provide a high-quality dyeing method suitable for dyeing small lots of many varieties. An object of the present invention is to obtain short fibers that maintain dry heat shrinkage. Disclosure of the invention

The purpose of the above is that acrylic short fibers exhibiting dry heat shrinkage are dyed with a cationic dye in a warm bath at 80 ° C or lower, and acrylic short fibers and acryl short fibers exhibiting dry heat shrinkage are used. The acrylic short fiber which satisfies the dry heat shrinkage of 20 to 50% at 120 to 150, and has a dry heat residual shrinkage of at least 14% at 120 to 130. Acrylic staple fiber and acrylic staple fiber are dyed in a warm bath using a cationic dye. The method for dyeing acryl short fibers, which uses short fibers that exhibit dry heat shrinkage and is dyed in a warm bath at 80 ° C or lower, and the packing density of acryl short fibers in a warm bath, 0.2 gZcm ³ or more, which is a method for dyeing the acrylic short fiber. Achieved by BEST MODE FOR CARRYING OUT THE INVENTION

The acrylic short fiber used in the present invention is not particularly limited as long as it exhibits a dry heat shrinkage of 20% to 50% at 120 to 150.

Specific examples include, but are not limited to, acryl short fibers having the following composition. A polymer solution of the following (I) and (II) is mixed by any known method to obtain a spinning dope, and subjected to predetermined stretching as necessary, such as spinning stretching, primary stretching, and dry heat stretching. Can be obtained by shortening the fiber.

This fiber has a dry heat shrinkage of 20% or more.

(I) 40% by weight or more of acrylonitrile and a halogen-containing monomer and 20 to 60 to 95% by weight of a polymer consisting of 60% by weight

(II) a polymer comprising 30 to 75% by weight of acrylonitrile and 25 to 70% by weight of methyl acrylate; 5 to 40 parts by weight

It is also possible to use those in which the polymer (II) contains the sulfonic acid-containing monomer in an amount of 0 to 10% by weight.

(B type)

In another embodiment, 25 to 70% by weight of vinyl chloride may be used instead of the above 25 to 70% by weight of methyl acrylate.

This fiber also has a dry heat shrinkage of 20% or more. In still another embodiment, the content of the halogen-containing monomer in the polymer (I) is 20 to 54% by weight, the content of the sulfonic acid-containing monomer in the polymer is 0.5 to 6% by weight, 20 to 60% by weight of acrylonitrile, 35 to 78% by weight of (meth) acrylate ester instead of methyl acrylate, and 2 to 5% by weight of sulfonic acid-containing monomer Can also be used.

This fiber also has a dry heat shrinkage of 20% or more.

A specific example of the method for producing acryl-based staple fibers exhibiting a dry heat shrinkage of 20% to 50% at 120 to 150 ° 0 is described in detail below. And C type can be manufactured in almost the same manner.

The polymer (I) is produced by a known method called aqueous emulsion polymerization or solution polymerization of 40% by weight or more of acrylonitrile and 20 to 60% by weight of halogen-containing monomer and 0.5 to 5% by weight of sulfonic acid-containing monomer. After removing the residual monomers, the process is usually dissolved in a spinning solvent or used as a spinning stock solution.However, the polymer polymerized in the following process has few voids generated during spinning, and the This is preferable because gloss is not lost. The polymer (I) is composed of 20 to 60% by weight of a halogen-containing monomer composed of vinyl chloride, vinylidene chloride or vinyl bromide or a mixture thereof, acrylonitrile and a small amount of, for example, 0.5 to 5% by weight of arylsulfone. Monomers such as sodium acrylate, sodium styrenesulfonate or sodium 2-acrylamido-2-methylpropanesulfonate are treated with azobisisopropane in an organic solvent such as dimethylformamide, dimethylsulfoxide or dimethylacetamide. Polymerization is carried out using a polymerization initiator such as thyronitrile and azobisdimethylvaleronitrile.

Particularly preferably, a polymer having a composition of 5 to 40% by weight of sodium arylsulfonate, 10 to 85% by weight of acrylonitrile, and 10 to 50% by weight of a halogen-containing monomer is prepared by the above polymerization method in dimethylformamide. In a dimethylformamide solution containing the polymer, 20 to 60% by weight of a halogen-containing monomer and acrylonitrile and, if necessary, sodium arylsulfonate are present in the presence of other additives such as a coloring inhibitor. Polymerize underneath.

The unreacted monomer in the obtained polymerization dope is removed at a temperature as low as possible using a low evaporator or a rotary thin film evaporator, and then the polymer concentration is adjusted to 20 to 30% by weight. Then, additives are added to obtain a spinning solution of the polymer (I).

On the other hand, for the polymer (II), a polymer of 30 to 75% by weight of acrylonitrile, 70 to 25% by weight of methyl acrylate and 0 to 10% by weight of a sulfonic acid-containing monomer was prepared in dimethylformamide. Polymerization is performed by a polymerization method, and the unreacted monomer in the obtained polymerization dope is removed. Thereafter, the concentration of the polymer (II) is adjusted to 20 to 30% by weight.

Next, the solutions of the polymers (I) and (Π) are mixed in a ratio of 0.6 to 95 parts by weight: 5 to 40 parts by weight (all known methods can be used for mixing). A spinning dope is obtained. The spinning dope is spun from a normal spinneret into a coagulation bath. Coagulation The solid bath is preferably an aqueous solution of the same organic solvent as the organic solvent of the spinning dope to reduce the cost of solvent recovery and simplify the recovery process. The organic solvent concentration is 40 to 70% by weight, preferably 50%. The temperature is 15 to 35 ° C, preferably 18 to 28 ° C.

The undiluted spinning solution is spun into a coagulation bath, and the coagulated filament is usually subjected to spinning through a spinning bath of a numerical value with a gradually decreasing solvent concentration. The spinning draw ratio is usually 3 times or more, preferably 4 to 10 times, and more preferably 5 to 8 times. After spinning and stretching, wash in a water bath at 50 ° C or more, apply oil before drying, and dry and bake with a hot roller type or a dryer used in combination with a hot air dryer. In this drying step, it is preferable to perform a slight shrinkage of about 10% as compared with the constant-length tension drying in terms of drying, baking effect, prevention of mechanical overload, and the like.

For ordinary regular acrylic fiber, primary stretching is often used before drying.However, in the production of high shrinkage fibers, primary stretching after drying is more efficient in terms of shrinkage performance, fiber gloss and dyeability. More effective in terms.

The primary stretching is performed with a wet heat of 60 to L0 ° C, preferably 80 to L0 ° C, and the primary stretching magnification is the amount of the halogen-containing monomer in the polymer (I) and the polymer in the fiber. Although it depends on the content of (II), it is better to carry out at the draw ratio immediately before entering the overdrawing region from the viewpoint of fiber performance such as shrinkage performance, strength, gloss and dyeability, operability, and productivity.

Looking at the relationship between the primary draw ratio and the fiber performance (here, the shrinkage ratio), the shrinkage ratio increases with the increase in the draw ratio where the draw ratio is low, but the shrinkage ratio increases when the draw ratio exceeds a certain ratio. Reaches saturation, or conversely, the draw ratio decreases. The stretch ratio or more is called an overstretched region. In this overdrawing region, not only saturation and reduction of the shrinkage rate, but also drawbacks such as a decrease in the strength and elongation of the fiber, a decrease in the dyeability, and a break in single yarn occur.

One large continuous shrinkage after dry baking and before primary stretching e.g. 20-5 A step of performing 0% shrinkage and then performing primary stretching may be employed.

The fiber after the primary drawing is subjected to post-oil adhesion and mechanical crimping, and

Dry at a temperature of less than 80 ° C, preferably 80 ° C, so as not to cause shrinkage.

Next, the fibers are shortened by cutting to an appropriate fiber length by a conventional method. However, in the case of the C type, a wet heat shrinkage / dry heat drawing step is applied after the primary drawing and before the crimping.

Specifically, after the primary drawing, the fibers are subsequently contracted by moist heat. The temperature is from 80 ° C to 130 ° C, preferably from 90 ° C to 115 ° C. Shrinking at low temperatures does not provide the desired shrinkage. At high temperatures, shrinkage between fibers is so severe that shrinkage at high temperatures has a serious effect on fiber properties and operability. The shrinkage ratio varies depending on the amount of the halogen-containing monomer in the polymer (I) and the content of the polymer (II) in the fiber. However, considering the shrinkage performance, fiber performance, operability, productivity, etc. It is preferably about 0.95 times.

After this wet heat shrinkage, oil is attached to the fiber, and dry heat drawing is performed. The stretching temperature is from 80 to 140 ° (preferably from 90 to 110 ° C. If the stretching temperature is too low, the stretching ratio is not sufficient, and the fiber is whitened at a low ratio. Conversely, if the drawing temperature is too high, sticking between the single fibers, yellowing due to heat, etc. are observed, and the dry heat shrinkage is adversely affected.

According to the above-mentioned method, an acrylic material exhibiting a dry heat shrinkage of 20% to 50% at 120 to 150 which is suitably used as a yarn for dyeing in the present invention. Short fibers can be produced.

The cationic dye used in the present invention has a positive charge and is adsorbed on a fiber having a negative charge such as a sulfonate group or a carboxylic acid group. I do. For example, a maker name Nichilon dye etc. is mentioned. Among them, dyes that can be quickly adsorbed on fibers even when dyed at a low temperature are preferable.

For example, those having an index / mixture (Imix.) Of C or more are preferable, and those of B or more are particularly preferable.

Although the concentration of the dye is not particularly limited, for example, 5% by weight or less per fiber weight is suitably used.

The dyeing temperature is at most 80 ° C, preferably at most 75 ° C, particularly preferably at most 70 ° C. By dyeing at a low temperature of 80 or less, it is possible to maintain high residual shrinkage after dyeing.

The dyeing time is preferably 30 to 50% longer than generally used, for example, about 30 to 60 minutes, but is not limited thereto.

When dyeing a dark color such as black, for example, it is preferable to use a dyeing agent such as an ether cyanide compound.

The concentration of the propellant is not particularly limited, but, for example, 10% by weight or less per fiber weight is suitably used. Further, when the content is 5% by weight or less, a decrease in residual shrinkage can be suppressed, and therefore, it is particularly preferable.

At the time of dyeing, the packing density of the acrylic short fibers is preferably such that shrinkage of the short fibers can be physically suppressed, for example, preferably 0.20 gZcm ³ or more, more preferably 0.30 gZcm. ^{It is 3} or more, more preferably 0.35 g / cm ³ or more. However, from the viewpoint of exerting the effect of physically restricting shrinkage, it is preferably 0.37 gZ cm ³ or more, particularly preferably 0.45 g / cm ³ or more.

It is preferable that the soaping after dyeing is such that shrinkage of the acrylic short fibers can be suppressed as much as possible. However, from the viewpoint of maximizing the use of the soaping effect, the heating time is preferably 65 ° C or more and 20 minutes or more. Drying after soaping is preferably performed at 90 ° C. or less from the viewpoint of preventing shrinkage of the acrylic short fiber. More preferably, it is 80 or less.

By optimizing the packing density, soaping conditions and drying conditions described above, the shrinkage of acrylic short fibers from dyeing to drying is suppressed to 5% or less (8% or less for medium and dark colors). Becomes possible.

The acrylic short fiber used in the present invention can be dyed after being blended with another fiber, and can also be blended with another fiber after dyeing and used for commercialization.

The acryl-based short fibers obtained by the present invention maintain high dry heat shrinkage even at low temperatures. In particular, those having a dry heat residual shrinkage of 120 to 130 ° (: 14% or more) are suitable for high pile products.

An example will be described below, and prior to that, a method for evaluating acrylic short fibers in the example will be described.

(Wash fastness)

J I S L 0 844 (A-2)

(Water fastness)

J I S L 0 846 A method

(Fastness of friction)

J I S L 0 849.1. Gakushin type friction test

(Light fastness)

J I S L 0 842 (Ultraviolet light-bon arc light test)

(Sweat fastness)

J I S L 0 848 A method

(Fastness of sublimation) JISL 0 8 7 9 (Robustness test for dry heat treatment)

(Dry cleaning fastness)

J I S L 0 8 6 0 A method

(Achievement of target hue)

〇; Achieve target hue.

X: Target hue is not achieved.

Example 1

(Dark color dyeing)

The polymer solutions of the following (I) and (Π) are mixed by any known method to obtain a stock solution for spinning, and the yarn spun with the stock solution for spinning is spin-drawn by a usual method and then dried. The fiber after oil adhesion is subjected to dry heat drawing after primary heat drawing and shrinkage, and is shortened by a conventional method. An acrylic short fiber exhibiting 7% dry heat shrinkage was obtained.

(I) a polymer comprising 55% by weight of acrylonitrile, 42% by weight of halogenated vinylidene chloride and 3% by weight of sulfonic acid-containing monomer; 70 parts by weight;

(II) A polymer comprising 50% by weight of acrylonitrile, 48% by weight of methyl acrylate, and 2% by weight of a monomer containing sulfonic acid; 30 parts by weight

The acryl-based short fibers were packed in an Obermeier dyeing machine at a density of 0.37 g / cm ³ and dyed at a maximum temperature of 72 ° C. for 60 minutes. As the dye, a black dye of I mix. B (Nichilon Black manufactured by Nissei Kasei Co., Ltd.) was used at a concentration of 4.5% by weight based on the weight of the fiber. Carrier Gin K (manufactured by Nissei Chemicals, Inc.) was used in an amount of 3.0% by weight per fiber weight.

Soaping was performed at 65 ° C for 30 minutes, and drying was performed at 90 for 5 minutes. The target hue is black (RAL—Kl RAL 9004). Example 2

(Medium color dyeing)

The acrylic short fibers exhibiting a dry heat shrinkage of 37% under dry heat conditions of 150 ° C. for 5 minutes used in Example 1 were applied to an O.O.Maya single dyeing machine at 0.37 gZcm ^3. And dyed at a maximum temperature of 70 ° C for 30 minutes. As the dye, a yellow dye of I mix. A to B (a blend of Nichilon OrangeGL, Nichilon RedGL and Nichilon BlueGL manufactured by Nissei Kasei Co., Ltd.) was used in an amount of 0.915% by weight per fiber weight Used at concentrations.

Soaping was performed at 65 ° C for 20 minutes, and drying was performed at 90 ° C for 5 minutes. Note that the target hue is Melon Yellow (RAL-Kl RAL 12028).

Example 3

(Dark color dyeing)

The acrylic short fibers exhibiting a dry heat shrinkage of 37% under dry heat conditions of 150 ° C. for 5 minutes used in Example 1 were applied to an O.O.Maya single dyeing machine at 0.37 gZcm ^3. At a maximum temperature of 7 Ot for 60 minutes. As the dye, a blue dye (a blend of Nichilon OrangeGL, Nichilon RedGL and Nichiion BlueGL, manufactured by Nissei Kasei Co., Ltd.) of I mix. Used at concentrations.

Soaping was performed at 65t for 20 minutes, and drying was performed at 90 ° C for 5 minutes. The target hue is Knightble (RAL—Kl RAL 5022). Table 1 shows the results of evaluation of the residual shrinkage and the like in each of Examples 1 to 3. Dyed goods

Color fastness

Residual dry heat after dyeing process Target shrinkage rate Light resistance Evaluation item Washing fastness Hue Occurrence shrinkage rate (%) Achieving property (%) 1 500 ° C 20 0

5 minutes Time Example 1 7.1 2 6.0 5 5 5 3 4 〇 Example 2 2.2 3 0.0 5 5 5 4-5 4 〇 Example 3 4.9 2 8.5 5 4 4 2-3 4 〇

As can be seen from Table 1, the acrylic short fibers of Examples 1 to 3 can obtain the target hue and have a sufficient dry heat residual shrinkage, and are suitable as shrinkable cotton for high pile and pore products. Was.

In addition, the high pile and pore products manufactured using the acrylic short fibers of Examples 1 to 3 had a very favorable texture because the acrylic short fibers sufficiently shrunk.

Example 4: I 2

(Dark color dyeing)

Using the same composition as that used in Examples 1 to 3, and adjusting the stretching conditions, dry heat of 120 ° C for 5 minutes, 130 ° C for 5 minutes, and 150 ° C for 5 minutes Under the conditions, acrylic short fibers exhibiting 26.0%, 30.5%, and 37.1% of dry heat shrinkage were obtained. This was packed in an Ober-Mayer-I dyeing machine at a density of 0.45 gZcm ³ and dyed at a maximum temperature of 65 ° C for 40 minutes. Dye types and dyeing densities listed in Table 2 were used. b

* Concentration per fiber weight

Table 3 shows the results of evaluation of the residual shrinkage and the like.

Table 3

As can be seen from Table 3, the acrylic short fibers dyed by the method of the present invention have a sufficient dry heat shrinkage even after dyeing, and in particular, a dryness of 14% or more suitable for high pile products. One having heat residual shrinkage was also obtained. In addition, Table 411 and Table 412 show the results of evaluation of the fastness after dyeing for the case without soaping and the case with soaping, respectively.

Color Wash fastness Water fastness Light fastness

-B Robustness Original transfer solution Original transfer solution Dry τ Raw fabric Dyeing and decoloring Dyeing and declosing Upper stage: No solid M

Bottom: So-pin Yes Color Color Color

Net cotton silk cotton

4 Carmine Red 5 4-5 5 2 5 4-5 5 5 4-5. 3 5 After leaching and drying 5 5 5 2-3 4-5 3-4

5 Telemagenta 5 5 5 2-3 5 5 5 5 4-5 3-4 b After re-linking and drying 5 5 5 2-3 4-5 3-4

"

h- 1 6 Melon iel low 5 5 5 2-3 5 5 5 5 4-5 3-4 5 Re-pin & dry 5 5 5 3 5 4

7 Night Blue 5 4 4-5 1-2 5 5 5 5 4 3 5 So-Pink '& After Drying 5 5 5 3 5 5 5 5 4-5 3 5

8 Leaf Green 5 5 5 2-3 5 5 5 5 5 3 5 Repin & dry 5 4-5 4-5 3 4-5 3-4

9 Pale Green 5 5 5 2-3 5 5 5 5 5 4-5 5 After leaching & drying 5 5 5 3-4 5 4-5

"

10 Deep Orange 5 5 5 3 5 5 5 5 5 3-4 5 Sohi Nok & Beggar 5 5 5 3 4-5 4

11 Pastel Violet 5 5 5 4 5 5 5 5 5 4 5 Re-pinge & dry 5 5 5 4-5 5 4-5

12 Pastel Blue 5 5 5 4 5 5 5 5 5 4 5 After re-pinking and drying 5 5 5 4 5 4-5

Upper: Sweat fastness Sublimation Dry clean garlic ^f Fastness Sohi. Nk ',

C, acid acidity

Cloth dyed cloth

Original cloth transfer liquid Original cloth transfer liquid

-k ° link ',, BL

Change out change change out

Yes

Color b color color

Net cotton color cotton

4 5 4 4-5 3-4 5 4 4-5 3-4 4-5 5 4-5 4 or more

5 5 5 5 5 5 5 5 5 4-5 5 4-5 4 or more

6 5 4-5 5 4-5 5 4-5 5 5 4-5 5 4-5 4 or more en

7 5 3 3-4 4 5 3 3-4 4-5 3-4 5 4 Silk 3, cotton 3, others 4 or more

5 5 4- 5 5 5 5 4- 5 5 4- 5 5

Out 8 5 5 5 5 5 5 5 5 4-5 5 4-5 4 or more

9 5 5 5 5 5 5 5 5 4-5 5 4-5 4 or more Example 1 0 5 5 5 5 5 5 5 5 4-5 5 4-5 4 or more

1 1 5 5 5 5 5 5 5 5 4-5 5 4-5 4 or more

1 2 5 5 5 5 5 5 5 5 4-5 5 4-5 4 or more

I As can be seen from Table 4-1 and Table 4-2, the acrylic short fibers dyed by the method of the present invention had sufficient color fastness.

Comparative Examples 1-2

Table 5 shows the results of treating the acrylic short fibers obtained in Example 4 with a warm bath at 85 ° C and 90 ° C.

Table 5

As can be seen from Table 5, when the treatment was carried out at a high temperature exceeding 80 ° C., the treatment caused a considerable increase in shrinkage, and the dry heat residual shrinkage after the treatment was inferior to those of the examples. Industrial applicability

The acrylic short fiber of the present invention has a target hue and fastness irrespective of dark color or light color, and has a high residual shrinkage. As a result, it can be used for shrinking under dry heat conditions.

Claims

The scope of the claims

1. Acrylic staple fibers that exhibit dry heat shrinkage and are dyed with thione dye in a warm bath at 80 ° C or lower.

2. The acryl-based short fiber according to claim 1, wherein the acrylic short fiber exhibiting dry heat shrinkage satisfies a dry heat shrinkage of 20 to 50% at 120 to 150 °.

3. The acrylic short fiber according to claim 1, wherein the dry heat residual shrinkage is 14% or more at 120 to 130 ° C.

4. In the method of dyeing acrylic short fibers in a warm bath dyeing using a cationic dye, the acrylic short fibers have a dry heat shrinkage of 20% to 50% at 120 to 150 ° C. A method for dyeing acrylic short fibers, characterized by dyeing in a warm bath of 80 or less, using the short fibers that exert their effects.

5. The method for dyeing acrylic short fibers according to claim 4, wherein the packing density of acrylic short fibers in the warm bath is 0.2 gZcm3 or more.

Claims of amendment

[May 31, 2002 (31.05.02) Accepted by the International Bureau: Claims at the time of filing

1, 3 and 5 have been amended; claim 2 originally filed has been withdrawn; new claim 6 has been added; other claims remain unchanged. H page)]

1. (After correction) Short acrylic fibers exhibiting dry heat shrinkage of 20 to 50% at 120 to 150 ° C are dyed with a cationic dye in a warm bath at 80 ° C or lower. Acrylic staple fibers characterized by being made.

2. (Delete)

3. The acrylic short fiber according to claim 1, wherein (after correction) the dry heat residual shrinkage is at least 14% at 120 to 130 ° C.

4. In the method of dyeing acrylic short fibers using a warm dye in a warm bath using a cationic dye, the acrylic short fibers are dried at 120 to 150 ° C by 20% to 50%. A method for dyeing acrylic short fibers, wherein short fibers exhibiting heat shrinkability are dyed in a warm bath at 80 ° C or lower.

5. (corrected) the packing density of the acrylic staple fibers into a hot bath, 0. 2 gZc m ³ or more as defined in Claim 4 The method of dyeing acrylic short fiber according to.

6. (Additional heat) Acrylic short fibers that exhibit dry heat shrinkage are dyed with a cationic dye in a warm bath of 80 or less, and the residual dry heat shrinkage is 120 to 130 ° C. And at least 14% by weight.

18

Paper captured (Convention No. II) Statements under Article 19 (1) of the Convention Claim 1 was limited to acryl-based staple fibers exhibiting a specific range of dry heat shrinkage. Paragraph 3 has been amended in accordance with the deletion of paragraph 2. Paragraph 5 deletes "Characteristics." Paragraph 6 was newly added in accordance with the amendments in paragraphs 1 and 3.

The invention of the present application is to obtain acrylic short fibers maintaining high dry heat shrinkability by dyeing acrylic short fibers exhibiting dry heat shrinkage in a warm bath under specific conditions. Does not describe dry heat shrinkability. Citation 3 describes that dry heat is applied to the acrylic fiber, but it is clear that the meaning of dry heat is different from dry heat shrinkage as a fiber property.

The correction of the claims by specifying the dry heat shrinkage clarifies the difference between the present invention and each cited document.