JP2001248027A - Heat-resistant crimped yarn - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a crimped yarn hard to produce fluffs or dust, maximally suppressed in deterioration of the quality inherent in heat-resistant, high- performance fiber due to heat treatment in the production process, thereby having good stretch elongation percentage, elastic recovery percentage of stretch and appearance without losing excellent properties such as heat resistance or flame retardancy inherent in such a heat-resistant, high-performance fiber. SOLUTION: This heat-resistant crimped yarn consists of heat-resistant, high-performance fiber and is subject to no quality deterioration by heating, and is characterized by being >=6% in stretch elongation percentage, >=40% in elastic recovery percentage of stretch and 0.15-3.5 N/tex in tenacity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-resistant crimped yarn made of heat-resistant and high-performance fiber such as aramid fiber and a method for producing the same. More specifically, a heat-resistant crimped yarn that has not only excellent heat resistance, flame retardancy, high strength properties, but also a good elastic elongation and elasticity and an excellent appearance, and is less likely to generate fluff and dust, And a method for producing the heat-resistant crimped yarn, comprising performing a high-temperature high-pressure steam or high-temperature high-pressure water treatment or a dry heat treatment. The present invention also relates to a bulky and stretchable fiber product comprising the heat-resistant crimped yarn.
In particular, high heat work in blast furnaces, various labor work such as welding work or agricultural work in sheet metal work, painting process of products in the automobile industry or electric product industry, or manufacturing in the precision machine industry, aircraft industry or information equipment industry It relates to work clothes and gloves necessary to protect the body and hands in various processes, such as sports, surgery, etc.

[0002]

2. Description of the Related Art While general-purpose thermoplastic synthetic fibers such as nylon and polyester fibers melt at about 250 ° C., heat-resistant and highly functional materials such as aramid fibers, wholly aromatic polyester fibers or polyparaphenylene benzobisoxazole fibers. The fiber does not melt at about 250 ° C., and its decomposition temperature is as high as about 500 ° C. Further, the non-heat-resistant general-purpose fibers such as nylon and polyester fibers have a critical oxygen index of about 20 and burn well in air, whereas the heat-resistant high-performance fibers have a critical oxygen index as described above. It is about 25 or more, and it burns in the air by approaching a heat source flame, but cannot keep burning if the flame is kept away. Thus, the heat-resistant and high-performance fiber is a material excellent in heat resistance and flame retardancy. Therefore, for example, aramid fiber, which is a heat-resistant and high-performance fiber, is used in clothing products where there is a great risk of exposure to fire or high heat, such as firefighting clothing, racing suits for automobile racing, workwear for steelmaking, or workwear for welding. It is used favorably. Among them, para-aramid fiber, which has both high heat resistance and high strength properties, is used in sports clothing, work clothes, ropes, tire cords, etc., which require tear strength and heat resistance. It is also used for gloves. On the other hand, meta-aramid fibers are excellent in heat resistance as well as weather resistance and chemical resistance, and are used for firefighting clothes, heat insulating filters, heat-resistant dust filters, electric insulating materials, and the like.

Heretofore, when producing fiber products such as clothing products using these heat-resistant and high-performance fibers, the fibers have only been used in the form of non-crimped filament yarn or spun yarn. . However, even if non-crimped yarns such as filament yarns and spun yarns are processed into fabrics to produce clothing products such as firefighting clothing, racing suits or work clothes, the yarns have sufficient elasticity. As a result, the elasticity of the clothing product was inferior. As a result, when the clothing product is worn, there is a problem that wearing comfort is poor and activity is difficult.

In particular, in the case of working gloves used in the aircraft industry, the information equipment industry, or the precision machine industry which handle precision parts, conventional working gloves made of non-crimped yarn have poor workability when worn, so work is difficult. This has led to a decrease in efficiency. Also, in the medical field, for example, when operating a patient with a disease that may be infected with blood such as AIDS,
The doctor wears rubber gloves or elastomer gloves (hereinafter referred to as "rubber gloves") so that the blood of the patient does not adhere. In addition, for example, rescue workers use rubber gloves or the like to protect themselves from blood or body fluid of patients who have not been confirmed to have an infectious disease because they are in contact with unspecified injured or sick people. However, since rubber gloves and the like are easily torn with a surgical instrument such as a scalpel, it is not possible to sufficiently protect medical personnel such as doctors and rescue workers from a scalpel or a syringe needle to which the blood of the patient has adhered. Therefore, it is conceivable to wear gloves woven or knitted with the above-mentioned heat-resistant and high-performance fibers having high mechanical strength inside rubber gloves or the like. Inferiority lowers the work efficiency of medical personnel such as doctors and paramedics. Therefore, there is a demand for a glove having elasticity and difficulty in cutting, which is thin and does not impair workability, and which can be used inside a rubber glove or the like.

Further, conventionally, spun yarns are generally formed by spinning short fibers of about 38 mm or about 51 mm into yarns, and therefore, the short fiber ends protrude from the surface of the yarn to form a fluff. Workwear and gloves made from spun yarn made of heat-resistant high-performance fibers lose their fluff due to friction during use.For example, they adhere to clean rooms or painted surfaces in environments where dust in the air has been removed. There is a problem with work clothes and gloves in paint factories where dust that degrades the commercial value of the product is required.Fiber products made of heat-resistant high-performance fibers, such as work clothes and gloves, which are less likely to generate fluff and dust, are required. Was.

[0006] As described above, the heat-resistant and high-performance fibers originally possessed by the heat-resistant and high-performance fibers made of non-crimped yarns are intended to improve the activity or workability of the fiber products and to reduce the generation of fluff and dust. A heat-resistant crimped yarn that has a good stretch ratio, a stretch elastic modulus, and an excellent appearance without losing excellent properties such as heat resistance and flame retardancy, and is less likely to generate fluff and dust is highly desired. Was.

In view of such market demands, many studies and proposals have been made on methods for imparting crimp to heat-resistant crimped yarns or high-performance heat-resistant fibers (Japanese Patent Application Laid-Open No. 48-1981).
8, JP-A-53-114923, JP-A-3-2711
7). Specifically, a method using a crimping method of a general thermoplastic synthetic fiber such as a nylon or polyester fiber is used. For example, a method in which a low modulus fiber is mixed with a high modulus fiber such as a para-aramid fiber and crimping is applied by indentation (Japanese Patent Laid-Open No. 1-192839). (In the case of a meta-aramid fiber, a non-contact heater heated to 390 ° C. or higher and lower than 460 ° C.) is subjected to false twist crimping, followed by relaxation heat treatment. ) Are known. However, in any of the known methods, production of high-quality crimped yarn having good stretchability and elasticity; deterioration of yarn quality such as loss of strength, color change, fluffing or breakage due to heating. From the viewpoint of easiness of process control, facility simplicity, excellent productivity, low cost, etc., all of the technical issues to be overcome are not all solved. At present, there is no heat-resistant crimped yarn having excellent properties such as deterioration in physical properties of constituent fibers and excellent expansion / contraction elongation and the like.

[0008]

SUMMARY OF THE INVENTION In view of the above-mentioned problems of the prior art, the present invention suppresses the deterioration of the quality of heat-resistant and high-performance fiber yarn due to heat treatment at the time of production as much as possible, and reduces the heat resistance inherent in the heat-resistant and high-performance fiber. Another object of the present invention is to provide a heat-resistant crimped yarn having a good stretchability and elasticity and an excellent appearance without losing excellent properties such as flame retardancy and hardly generating fluff and dust. And Another object of the present invention is to provide a method for producing a heat-resistant crimped yarn that is practical in terms of productivity, equipment, cost, and the like. Further, the present invention provides
(A) excellent in elasticity, heat resistance, mechanical strength and appearance,
(B) Workability is good by fitting well to the body such as hands,
(C) It is an object of the present invention to provide a fiber product, particularly a glove, which has advantages in industrial manufacturing such as being less likely to generate fluff and dust, (d) being easy in process control, being excellent in productivity and being low in cost. Aim.

[0009]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, a crimped yarn having a specific expansion / contraction ratio, expansion / contraction elasticity and strength, and having no quality deterioration due to heating. The use of heat-resistant and high-performance fibers in the form of can significantly improve the workability or activity of fiber products, compared to the use in the form of non-crimped yarns such as filament yarns and spun yarns. It has been found that the conventional problems described above, such as the generation of fluff and dust even when subjected to friction during use, can be solved at once. In addition, as a result of examining the method of manufacturing the heat-resistant crimped yarn, the first twist was first added to the heat-resistant and high-performance fiber yarn, and the twist was set by heat treatment using high-temperature high-pressure steam or high-temperature high-pressure water treatment or dry heat treatment. It has also been found that the above-described excellent heat-resistant crimped yarn can be manufactured by fixing and then untwisting by giving a second twist in the direction opposite to the first twist. Further, since the filament yarn of the heat-resistant and high-performance fiber is apt to slip, it is often difficult to produce a fiber product by using a mechanical woven knitting such as a woven knitting. However, it has been found that such a problem can be solved by using the heat-resistant crimped yarn according to the present invention. Furthermore, it has been found that a bulky and elastic fiber product made of a heat-resistant crimped yarn such as the glove according to the present invention has an advantage that fluff and dust are less likely to be generated. That is,
As described above, the spun yarn has a short fiber end protruding into the yarn surface and has a fluff shape.Thus, a fiber product made of a spun yarn of heat-resistant and high-performance fiber tends to fall off due to friction during use, Since the heat-resistant crimped yarn according to the present invention is composed of long fibers, there is no fuzz on the yarn surface, and thus, textile products such as work clothes made therefrom are single fibers even when subjected to friction during use. The fluff, which is the cut end of the fiber, hardly occurs, and the fluff of the single fiber does not fall off. Therefore, in the precision machinery industry, the aircraft industry, or the information equipment industry, for example, when working with electronic components used in airplanes or computers, for example, work gloves should be degraded over time and fibers should be broken and clean. Since it is necessary to avoid a situation where dust is generated by scattering into the space, the fiber product of the present invention, particularly gloves, which has an advantage that fluff and dust are unlikely to be generated, is useful in the above industry. In addition, in the painting process during the manufacturing of aluminum building materials, home appliances, automobiles, etc., if the fluff or dust adheres to the painted surface, the commercial value of the product is reduced. Gloves, in particular, are also useful in these industries.
The present inventors have further studied and completed the present invention.

[0010] That is, the present invention comprises (1) a heat-resistant and high-performance fiber having a single-fiber fineness of 0.02 to 1 tex, a stretch and elongation of 6% or more, a stretch and elastic modulus of 40% or more, and a strength of 0.1% or more. A heat-resistant crimped yarn having a quality of 15 to 3.5 N / tex without deterioration due to heating; (2) a heat-resistant and high-performance fiber made of para-aramid fiber, wholly aromatic polyester fiber or polyparaphenylene benzobis The heat-resistant crimped yarn according to the above (1), which is an oxazole fiber and has a strength of 0.5 to 3.5 N / tex, (3)
The heat-resistant crimped yarn according to (2), wherein the para-aramid fiber is a polyparaphenylene terephthalamide fiber,
(4) The heat-resistant high-performance fiber is a meta-aramid fiber, and has a stretch-elongation of 50 to 300%, and the heat-resistant crimped yarn according to the above (1), and (5) a meta-aramid fiber. Is a polymetaphenylene isophthalamide fiber, the heat-resistant crimped yarn according to the above (4), (6) the above (1) to
(5) a bulky and stretchable fiber product containing 50% or more of the fiber portion of the heat-resistant crimped yarn according to (5); (7) a bulky and stretchable fiber product according to (6) which is a glove; (8) Precision machine industry, aircraft industry, information equipment industry, automobile industry,
The glove according to (7), (9) a firefighting suit, a racing suit for automobile racing, or a workwear for steelmaking, welding or welding used in the electric appliance industry, medical surgery or hygiene field. 6) The bulky and stretchable fiber product described in 6), (10) After twisting the heat-resistant and high-performance fiber yarn, heat setting is performed by high-temperature and high-pressure steam or high-temperature and high-pressure water treatment, and then untwisting the twist. (11) that the twist added to the heat-resistant high-performance fiber yarn has a twist coefficient K5,000 to 11,000 represented by the following formula, The method for producing a heat-resistant crimped yarn according to the above (10), wherein high-pressure steam or high-temperature and high-pressure water treatment is performed at a temperature of 130 to 250 ° C., wherein K = t × D ^1/2 [ t represents the number of twists (times / m), D
Represents fineness (tex). (12) The above-mentioned (10), wherein the heat-resistant and high-performance fiber is a fiber selected from the group consisting of para-aramid fiber, meta-aramid fiber, wholly aromatic polyester fiber and polyparaphenylene benzobisoxazole fiber. Or the method for producing a heat-resistant crimped yarn according to (11), (1)
3) The method for producing a heat-resistant crimped yarn according to the above (12), wherein the para-aramid fiber is a polyparaphenylene terephthalamide fiber; %, And the method for producing a heat-resistant crimped yarn according to any one of the above (10) to (13), and (15) the heat resistance obtained by the production method according to the above (12). (16) Twist is applied to the bulky and stretchable fiber product made of crimped yarn, (16) heat-resistant and high-performance fiber yarn, and then heat-set by dry heat treatment at a temperature equal to or lower than the decomposition start temperature of the heat-resistant and high-performance fiber. (17) A method for producing a heat-resistant crimped yarn, wherein the twist is untwisted.
Add 2,000 to 11,000 twists, 140 to 390 ° C
Heat setting by dry heat treatment at a temperature of the following, followed by untwisting of the twist, wherein the method for producing a heat-resistant crimped yarn according to the above (16), K = t × D ^1/2 [However, t represents the number of twists (times / m), and D
Represents fineness (tex). (18) The method according to (16) or, wherein, after the twist is added to the heat-resistant and high-performance fiber yarn, heat setting is performed by dry heat treatment, and then the step of untwisting the twist is continuously performed. The method for producing a heat-resistant crimped yarn according to (17), (19)
The method for producing a heat-resistant crimped yarn according to any one of the above (16) to (18), wherein the dry heat treatment is performed at a temperature of 200 to 330 ° C .; The fiber according to any one of (16) to (19), which is a fiber selected from the group consisting of a series aramid fiber, a meta series aramid fiber, a wholly aromatic polyester fiber, and a polyparaphenylene benzobisoxazole fiber. (21) The method for producing a heat-resistant crimped yarn according to any one of (16) to (20), wherein the para-aramid fiber is a polyparaphenylene terephthalamide fiber. And (22) the heat-resistant crimped yarn according to any one of (16) to (21), wherein the stretchable elongation of the heat-resistant crimped yarn is 6% or more and the stretchable elasticity is 40% or more. Manufacture of crimped yarn Law, (23) (16) - (2
2) A bulky and stretchable fiber product made of a heat-resistant crimped yarn obtained by the method described in any one of 1) and (24) a knitted fabric made of a heat-resistant and high-performance fiber yarn, and the knitted fabric is subjected to dry heat treatment. Or a method for producing a heat-resistant crimped yarn characterized by treating with high-temperature and high-pressure steam or high-temperature and high-pressure water, and then knitting the knitted fabric; (25) preparing a knitted fabric with a heat-resistant and high-performance fiber yarn;
The method for producing a heat-resistant crimped yarn according to (24), wherein the knitted fabric is treated with high-temperature high-pressure steam or high-temperature high-pressure water at 130 to 250 ° C. for 2 to 100 minutes, and then the knitted fabric is deknitted. (26) The heat-resisting method according to (24), wherein a knitted fabric is prepared from heat-resistant and high-performance fiber yarns, dried and heat-treated at a temperature of 140 to 390 ° C., and then the knitted fabric is deknitted. (27) The heat-resistant crimped yarn according to (25) or (26), wherein the heat-resistant crimped yarn has a crimp elongation of 6.5% or more. (28) a glove characterized by being woven and knitted with a yarn containing a heat-resistant and high-performance fiber crimped yarn, (29) the glove (2).
(8) The crimped yarn according to (2), wherein the crimped yarn has a stretchable elongation of 6% to 30% and a stretchable elasticity of 40 to 100%.
8) The glove according to 8), wherein the heat-resistant and high-performance fiber is a fiber selected from the group consisting of para-aramid fiber, meta-aramid fiber, wholly aromatic polyester fiber, and polyparaphenylenebenzobisoxazole fiber. The glove according to the above (28) or (29), (31) the glove according to the above (30), wherein the para-aramid fiber is a polyparaphenylene terephthalamide fiber, and (32) a heat-resistant high-performance fiber crimped yarn. However, after the twist is added to the heat-resistant and high-performance fiber yarn, heat-set by dry heat treatment or high-temperature and high-pressure steam or high-temperature and high-pressure water treatment, and then manufactured by a manufacturing method characterized by untwisting the twist. (28) to (28), which are heat-resistant and high-performance crimped fibers.
The glove according to any one of (31) and (33), wherein the glove is used in the precision machine industry, the aircraft industry, the information equipment industry, the medical operation, or the hygiene field. The described gloves.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention has a single yarn fineness of 0.02 to 0.02.
It is made of heat-resistant and high-performance fiber of 1 tex, and has a stretch rate of about 6% or more, a stretch modulus of about 40% or more, a strength of about 0.15 to 3.5 N / tex, and a quality by heating. A heat-resistant crimped yarn without deterioration is provided. The heat-resistant and high-performance fiber according to the present invention has a limiting oxygen index of about 25.
Fibers having the above flame retardancy and heat resistance having a thermal decomposition temperature of about 400 ° C. or more by differential scanning calorimetry are preferred. Examples thereof include aramid fiber, wholly aromatic polyester fiber (for example, Kuraray Co., Ltd., trade name Vectran), polyparaphenylene benzobisoxazole fiber (for example, Toyobo Co., Ltd., trade name Zylon), polybenzimidazole fiber, polyamide Examples include imide fibers (for example, product name Kermel, manufactured by Rhone Poulin Co., Ltd.), and polyimide fibers. Aramid fibers include meta-aramid fibers and para-aramid fibers. Examples of the meta-aramid fiber include a meta-type wholly aromatic polyamide fiber such as polymetaphenylene isophthalamide fiber (manufactured by DuPont, trade name: Nomex). Examples of the para-aramid fiber include polyparaphenylene terephthalamide fiber (manufactured by Toray DuPont, trade name Kevlar) and copolyparaphenylene-3,4'-diphenyl ether terephthalamide fiber (manufactured by Teijin Limited, trade name Technora) ) And the like. The heat-resistant crimped yarn according to the present invention may be composed of one kind of the heat-resistant and high-performance fibers, or may be composed of any two or more kinds of the heat-resistant and high-performance fibers.
Further, it can be used as a composite yarn obtained by blending with other known fibers such as polyester, nylon, and polyvinyl alcohol-based fibers, and twisting.

The single-fiber fineness of the heat-resistant high-performance fiber used in the present invention is about 0.02 to 1 tex, preferably about 0.05 to 0.6 tex, and more preferably about 0.1 to 0.6 tex.
It is preferably about 08 to 0.5 tex from the viewpoint of the flexibility of the heat-resistant crimped yarn according to the present invention and the ease of manufacturing the heat-resistant crimped yarn. The total fineness of the heat-resistant high-performance fiber yarn used in the present invention is not limited as long as it can be processed into a twisted yarn or a knitted fabric. In consideration of about 5-50
About 00 tex is preferable. In addition, the fineness is JIS
It is represented by tex (tex) defined in L0101 (1999). For example, 1 tex indicates that a fiber having a length of 1000 m has a mass of 1 g, and 10 tex indicates that a fiber having a length of 1000 m has a mass of 10 g. The larger the value represented by tex, the thicker the fiber.

In the heat-resistant crimped yarn according to the present invention, when the heat-resistant and high-performance fiber is a para-aramid fiber, a wholly aromatic polyester fiber or a polyparaphenylene benzobisoxazole fiber, the expansion and contraction of the crimped yarn is possible. The modulus is preferably about 6% or more, more preferably about 10 to 50%, and still more preferably about 15 to 40%, and the elastic modulus of the crimped yarn is about 40% or more. Preferably about 50 to 100%, more preferably about 60 to 1
00%, and the strength of the crimped yarn is about 0.1%.
About 5 to 3.5 N / tex, preferably about 0.5 to 3.5 N / tex.
About 5 N / tex is a preferred embodiment of the present invention.

In the heat-resistant crimped yarn according to the present invention, when the heat-resistant and high-performance fiber is a meta-aramid fiber, the crimped yarn has a stretch and elongation of about 6% or more, preferably about 50 or more. More preferably, it is about 50 to 300%, more preferably about 70 to 300%, and the elastic modulus of the crimped yarn is about 40% or more, preferably about 50 to 1%.
About 100%, more preferably about 70 to 100%, and the strength of the crimped yarn is about 0.15 to 1.0 N /
The preferred embodiment in the present invention is about tex.

The heat-resistant crimped yarn according to the present invention is characterized in that there is substantially no deterioration in quality due to heating. Examples of the quality deterioration due to heating include a decrease in the physical properties or appearance of the heat-resistant crimped yarn due to the heat treatment, and more specifically,
For example, reduction in strength of heat-resistant crimped yarn due to heat treatment, change in color tone, yarn breakage or fluffing and the like can be mentioned. For example, it is preferable that the strength retention of the yarn after the heat treatment is 30% or more, preferably 40% or more, and more preferably 50% or more, as a measure that the strength does not decrease. The strength retention can be calculated from the following equation.

## EQU1 ## Strength retention (%) = ｛Strength of heat-resistant crimped yarn (N
/ Tex) / strength of heat-resistant and high-performance fiber yarn before treatment (N / t)
ex)｝ × 100 Also, it cannot be said unconditionally because it differs depending on the type of heat-resistant and high-performance fiber. The lightness of the yarn after is about 80% of the lightness of the yarn before heating
Degree, preferably about 85%.

The present invention provides a bulky and elastic fiber product comprising the heat-resistant crimped yarn. The fiber product may be composed of only the above-mentioned heat-resistant crimped yarn, or may be a knitted or knitted product with other fiber yarns. However, when the fiber product is the above-mentioned mixed weave or mixed knit, about 5% or more, preferably about 25% or more, more preferably about 50% or more of the fiber component is heat-resistant crimp according to the present invention. It is preferably a yarn. The fiber yarn other than the heat-resistant crimped yarn is not particularly limited, and a known yarn may be used. The textile product according to the present invention is not particularly limited, and examples thereof include a fabric woven and knitted with a thread containing the above-described heat-resistant crimped yarn, gloves such as a heat-resistant safety glove using the fabric, firefighting clothing, and automobile racing. Racing suit,
Examples include clothing products in a situation where there is a great risk of exposure to flame or high heat, such as work clothes for steel making, welding or painting, heat-resistant materials such as heat-resistant dust filters, ropes or tire cords. The fiber product can be easily produced according to a method known per se. For example, as the glove, a commercially available computer glove knitting machine SFG or STJ (manufactured by Shima Seiki Seisakusho) is conveniently used. When using the above fibrous products, the above fibrous products may be used alone or in combination with other products having heat resistance or flame retardancy. Further, a process known per se may be performed. For example, the glove according to the present invention may be used for various operations as it is, or a resin may be applied to a part of the glove, particularly to the outer surface on the palm side or the entire outer surface of the glove. Examples of the resin therefor include vinyl chloride resin, latex, urethane resin, natural rubber and synthetic rubber, and the application of the resin increases the strength of the glove and makes the glove less slippery when grasped. The resin application may be performed according to a means known per se. Further, a rubber glove or an elastomer glove may be further put on the glove according to the present invention.

The present invention also provides a method for producing a heat-resistant crimped yarn which is practical in terms of productivity, equipment or cost. The method is, for example, twisting a yarn made of heat-resistant and high-performance fiber such as aramid fiber, and performing high-temperature high-pressure steam treatment or high-temperature high-pressure water treatment (hereinafter, simply referred to as “high-temperature high-pressure steam
Or performing a dry heat treatment, and then untwisting the twist. The yarn comprising the heat-resistant and high-performance fiber may be, for example, a spun yarn or a filament yarn produced by a method known per se. Among them, a filament yarn that does not easily generate fluff and dust is preferable. More specifically, firstly, firstly, a yarn or the like made of heat-resistant and high-performance fibers is first used.
Twist (either S or Z) is added, and if necessary, this is wound up on a heat-resistant bobbin made of aluminum or the like, heated to a specific temperature range, and heat-set to fix the twist. Next, a second twist (Z or S) in a direction opposite to the first twist is applied and untwisted to produce a heat-resistant crimped yarn. According to the method of the present invention, the single yarn constituting the yarn by applying the first twist takes a complicated spiral shape, and the shape is fixed by the heating action. However, by untwisting in the next step, the single yarn is released from the restraint due to twisting while retaining the shape when the first twist was given. As a result, each single yarn takes the form of a crimped yarn in an attempt to assume each arrangement based on the stored shape.

As described above, the method for producing a heat-resistant crimped yarn according to the present invention includes a production method by high-temperature and high-pressure steam treatment and a production method by dry heat treatment, depending on the means of heat setting. In the case of high-temperature and high-pressure steam treatment, there is an advantage that heating unevenness is small. That is, the fiber yarn portion which is extremely heated and causes quality deterioration,
The fiber yarn portion where the heating is not sufficiently performed due to insufficient heating hardly occurs. On the other hand, in the case of dry heat treatment,
(A) Since high-temperature high-pressure steam or high-temperature high-pressure water (hereinafter simply referred to as “high-temperature high-pressure steam”) for heat treatment is not used,
Twisting and fixing can be performed under atmospheric pressure, so that a high-pressure heat-resistant device is not required. (B) As a manufacturing process, not only a batch process but also a continuous process such as passing through a high-temperature processing region can be employed. There are advantages such as the use of hot air and a fluidized bed in the high-temperature treatment area.

Hereinafter, a production method by high-temperature and high-pressure steam treatment will be described in detail. In the manufacturing method, first, a first twist is added to a yarn made of a heat-resistant high-performance fiber. The yarn may be a filament yarn or a spun yarn. Among them, a filament yarn that does not easily generate fluff and dust is preferable. The first twist is given by the following equation: K = t × D ^1/2
[However, t represents the number of twists (times / m), D represents fineness (tex)
Represents The value of the twist coefficient K represented by
It is preferably about 11,000. More preferably, it is about 6,000 to 9,000. The above-mentioned range is preferable for the twist added to the yarn in order to appropriately crimp the yarn and to prevent the fiber from being cut by applying too much twist. The twist coefficient (K) is an index indicating the degree of twist regardless of the thickness of the yarn, and the higher the twist coefficient, the higher the degree of twist.

In the twisting step of adding the first twist, a well-known twisting machine such as a ring twisting machine, a double twister or an Italian twisting machine may be used. The resulting twisted yarn is preferably wound up on a bobbin. However, when wound on a bobbin at the time of twisting, there is no need to rewind.
Here, the bobbin is generally a core for winding a yarn, and a bobbin known per se may be used, but a bobbin made of a heat-resistant material such as aluminum is preferable. In the next heat setting step, it is preferable to provide small holes on the entire surface of the heat-resistant bobbin so that high-temperature and high-pressure steam can easily pass therethrough. At this time, the winding thickness of the yarn cheese or the yarn cone formed by winding the twisted yarn around the bobbin is preferably about 15 mm or more, and the winding density is about 0.4 to 1.0 g / cm ^3.
The degree is preferably about 0.5 to 0.9 g / cm ³ , more preferably about 0.6 to 0.9 g / cm ³ .

Next, a high-temperature high-pressure steam in a specific temperature range is
A high-temperature and high-pressure steam treatment for fixing the first twist is performed.
U. The high-temperature and high-pressure steam treatment is performed according to a technique known per se, for example,
For example, a high-temperature, high-pressure sealed container that can supply high-temperature, high-pressure steam inside
This is performed using a vessel. The high-temperature high-pressure closed container is known per se.
May be used, for example, to supply high-temperature, high-pressure steam
Steam lines and drain valves and drains for pressure relief at end of treatment
A pneumatic valve is connected, and the twisted yarn obtained in the previous process
With an opening for loading a bobbin
Having a structure with an openable lid
Is mentioned. Temperature conditions for high-temperature high-pressure steam treatment
About 130 to 250 ° C. is suitable, and preferably about 1 to about 250 ° C.
About 30 to 220 ° C, more preferably about 140 to 220
℃, more preferably about 150-200 ℃
You. Provides practical crimp while preventing fiber degradation
Therefore, the above temperature range is preferable. Pressure during the process
When using saturated steam as high-temperature high-pressure steam
Is uniquely determined physicochemically from the above temperature conditions.
Yes, the value of the saturated steam pressure at the lower limit temperature of 130 ° C is
2.70 × 10⁵Pa, and at an upper limit temperature of 250 ° C.
The value of the saturated water vapor pressure is 38.97 × 10⁵Equivalent to Pa
Therefore, for the present invention, about 130 ° C. to 250 ° C.
Temperature, about 2.70-39.0 × 10⁵Pressure of about Pa
It is preferable to carry out high-temperature and high-pressure steam treatment at However, the book
In the invention, it must always be treated with saturated steam
It does not mean that the pressure of water vapor is about 2.7 ~
39.0 × 10⁵What is necessary is just Pa. However,
Naturally, the pressure cannot be higher than the saturated steam pressure at the temperature.
It is. Above all, high-temperature high-pressure steam treatment is about 130 ° C ~
Temperature of about 220 ° C, about 2.7 to 23.2 × 10⁵Pa
About 140 ° C. to 220 ° C.
Temperature, about 3.5-23.2 × 10⁵Pressure of about Pa
More preferably, it is performed by force, about 150 ° C. to 200 ° C.
Temperature, about 4.8-15.6 × 10⁵At a pressure of about Pa
More preferably, it is performed. High instead of high temperature and high pressure steam
Hot and high pressure water may be used. In this case, the water temperature is about 1
About 30 to 250 ° C, preferably about 130 to 220 ° C
Degree, more preferably about 140 to 220 ° C., even more preferably
Preferably, the pressure is about 150-200 ° C, and the pressure is about 2.70-
39.0 × 10⁵About Pa, preferably about 2.7 to 2
3.2 × 10 ⁵About Pa, more preferably about 3.5 to 2
3.2 × 10⁵About Pa, more preferably about 4.8 to
15.6 × 10⁵It is about Pa. High-temperature and high-pressure water treatment plant
If high temperature and high pressure steam above and below and
Steam shall be read as high-temperature high-pressure water and water
You.

The time required for the high-temperature and high-pressure steam treatment varies depending on the winding amount of the yarn wound on the bobbin when the high-temperature and high-pressure steam treatment is performed, so it cannot be said unconditionally. It is sufficient if the above-mentioned predetermined temperature can be maintained for several minutes. But about 2 to 100
Of the order of minutes. It is more preferably in the range of about 3 to 60 minutes. The above range is preferable in order to heat-set the surface yarn and the internal yarn more uniformly among the yarns wound on the bobbin while preventing the fiber from deteriorating. The yarn wound on the bobbin may be forcibly cooled with cold air or the like after high-temperature and high-pressure steam treatment, but natural cooling at room temperature is preferred.

After the high-temperature and high-pressure steam treatment, the twisted yarn is given a second twist in a direction opposite to the first twist, and the twisted yarn is untwisted, whereby the heat-resistant crimped yarn according to the present invention can be produced. At the time of untwisting, a twisting machine known per se may be used as in the case of twisting.

Next, a manufacturing method by dry heat treatment will be described in detail. Examples of the production method by dry heat treatment include a batch-type production method and a false twisting method, and any of them may be used in the present invention. In these production methods, high-temperature high-pressure steam or high-temperature high-pressure water is not used for heat setting. That is, a heat treatment that does not use high-temperature high-pressure steam or high-temperature high-pressure water is referred to as dry heat treatment. In any of the batch-type manufacturing method or the false twist processing method,
If desired, a relaxation heat treatment may be performed. Examples of the relaxation heat treatment include a method of heating the obtained crimped yarn while elongating it to some extent. By performing the relaxation heat treatment, there is an advantage that the torque can be reduced without impairing the bulkiness of the yarn.

Hereinafter, a batch-type manufacturing method by dry heat treatment will be described. In the manufacturing method, first, a first twist is added to a yarn made of a heat-resistant high-performance fiber. The thread is
It may be a filament yarn or a spun yarn. Among them, a filament yarn that does not easily generate fluff and dust as described above is preferable. In the first twist, the value of the twist coefficient K is about 5,000 to 11, in order to prevent the fiber from being cut by appropriately crimping the yarn and applying too much twist.
It is suitably about 000, preferably about 6,000 to 9,000. In the twisting step of adding the first twist, for example, a known twisting machine such as a ring twisting machine, a double twister, or an Italian twisting machine may be used. The resulting twisted yarn is preferably wound up on a bobbin.
However, when wound on a bobbin at the time of twisting, there is no need to rewind. The bobbin may be a known bobbin,
For example, a material made of a heat-resistant material such as aluminum is preferable.

Next, a dry heat treatment is performed by heating to a specific temperature range and heat setting and fixing the first twist. The temperature condition of the heat treatment may be lower than the decomposition starting temperature of the raw fiber, preferably about 140 to 390 ° C, more preferably about 170 to 350 ° C, and most preferably about 200 to 350 ° C.
~ 330 ° C. The above range is preferable in order to make the degree of crimp of the obtained heat-resistant crimped yarn suitable for practical use, while avoiding deterioration of the yarn. Thus, in the dry heat treatment of the present invention, since it is not necessary to perform a high-temperature treatment at or above the decomposition starting temperature of the raw fiber, for example, a decrease in strength,
Deterioration of the yarn due to heating such as color change, fluffing or yarn breakage does not substantially occur. Specifically, for example, as a measure that the strength does not decrease, the strength retention of the yarn after the heat treatment is preferably 30% or more, preferably 40% or more, and more preferably 50% or more. is there. The strength retention is easily calculated from the above equation. Also, since it depends on the type of heat-resistant high-performance fiber, it cannot be said unconditionally,
For example, in the case of a meta-aramid fiber, the lightness of the yarn after the heat treatment is about 80% of the lightness of the yarn before the heat treatment, preferably 85%, as a guideline that the color tone of the yarn after the heat treatment does not change. % Is preferably maintained. The heater for the heat treatment may be a contact heater or a non-contact heater, and the heating may be performed by a known means such as a hot air method or a fluidized bed method. The heating time in the batch method varies depending on the type of the fiber, the thickness of the yarn, the heating temperature, and the like, and cannot be specified unconditionally. However, it is usually desirable to be about 2 to 100 minutes. More preferably about 1
The range is about 0 to 100 minutes, more preferably about 20 to 40 minutes. The above range is preferable in order to heat-set the surface yarn and the internal yarn more uniformly among the yarns wound on the bobbin while preventing the fiber from deteriorating. The dry heat treatment may be performed under any of a pressure, a reduced pressure, and a normal pressure, but is preferably performed under a normal pressure.

Next, after the dry heat treatment, the twisted yarn is given a second twist in a direction opposite to the first twist, and the twisted yarn is untwisted to produce the heat-resistant crimped yarn according to the present invention. it can. After the heat treatment, forcible cooling with cold air or the like may be performed, but it is preferable to leave it to air cooling. At the time of untwisting, a twisting machine known per se may be used as in the case of twisting.

Next, a manufacturing method using the false twisting method will be described. In the false twisting method, a yarn pulled out from a supply yarn cheese (a yarn wound up on a bobbin as a winding core) by a feed roller is wound up on a winding bobbin via a winding roller. A false twist spindle is provided between the feed roller and the take-up roller. When the yarn is wound around the pin of the false twist spindle and grasped, and the spindle is rotated, the yarn between the feed roller and the false twist spindle is subjected to, for example, S twist,
This is heat-set by a heater, and untwisted between the false twisting device and the take-up roller by applying a twist of, for example, Z opposite thereto to form a crimped yarn. A cooling zone is provided between the false twisting device and the take-up roller, and is preferably left to air cooling. In addition to the above-described false-twisting spindle, a method of applying false-twisting is a method in which the yarn is brought into contact with the inner wall of a cylinder rotating at a high speed, the outer periphery of a disk, or the surface of a belt running at a high speed to give false twist by friction.

In the false twisting method, the yarn made of the heat-resistant and high-performance fiber may be a filament yarn or a spun yarn, but a filament which does not easily generate fluff is preferred. Twisting by the false twisting spindle causes the yarn to be appropriately crimped and prevents the fiber from being cut by over-twisting.
About 11,000, preferably about 6,000 to 9,00
About 0 is preferable. In the present method, the twisting may be performed by any of, for example, a spindle method and a nip belt method, and is not particularly limited. When twisting is applied by the spindle method, a single pin may be used, but a preferred embodiment of the present invention uses a spinner having two or more pins, preferably four pins. That is, when twisting is performed using a one-pin spinner usually used in the spindle method, a thread made of a heat-resistant high-performance fiber is applied to the pin.
Although it is necessary to wrap the yarn, it is possible that the yarn made of the heat-resistant and high-performance fiber that is easily broken by friction may be broken during combustion. However, two or more pins, especially
Use a four-pin spinner that is shifted from the bottom and the bottom two, and pass the thread between the pins in a zigzag shape.
If the yarn enters from the upper central portion and exits from the lower central portion, twist can be added more efficiently. In this case, since the yarn is bent between the pins, twist is given by frictional resistance.

The heating temperature for the heat setting is the same as in the batch production method. On the other hand, since the present production method has a higher heat treatment effect than the batch production method, the heating time depends on the thickness of the yarn, but is about 0.5 to 300 seconds, preferably about 1 to 120 seconds. . The heater for the heat treatment may be a contact heater or a non-contact heater similarly to the batch-type production method, and the heating may be performed by a known means such as a hot air method or a fluidized bed method. In addition, even if a contact heater is used as a heater, tar-like mist hardly accumulates. Generally, even aramid fibers, which easily accumulate mist, can be processed stably. is there. The false twisting may be performed under any of pressure, reduced pressure, and normal pressure as in the batch-type manufacturing method, but is preferably performed under normal pressure.

The heat-resistant crimped yarn according to the present invention can be produced by the following method in addition to the above method. That is, a knitted fabric is prepared from heat-resistant and high-performance fiber yarns, and the knitted fabric is heat-set, and then the knitted fabric is unknitted (unknitted fabric) to obtain a heat-resistant crimped yarn. As the heat setting treatment, the above-described high-temperature and high-pressure steam treatment or dry heat treatment may be used, and the conditions and the like may be as described above. Among them, it is preferable to use a high-temperature and high-pressure steam treatment. In this case, the twist of the yarn at the time of forming the knitted fabric is preferably small because the yarn is restrained, and the twist coefficient is preferably from 0 to 500, and more preferably 0.

[0032]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below based on embodiments. The evaluation method of each physical property was based on the following method. Limit oxygen index: JIS K 7201: 1999 Measured by a combustion test method for polymer materials by the oxygen index method. Thermal decomposition point: JIS K 7120: 1987 Measured by a thermogravimetric method for plastics. Elasticity: JIS L 1013: 1999 Chemical fiber filament yarn test method 8.11. The stretch elongation and the stretch elastic modulus were measured by Method A. Fineness: Positive fineness was measured according to JIS L 1013: 1999 Chemical Fiber Filament Yarn Test Method 8.3. Tensile strength: Measured according to JIS L 1013: 1999 Chemical Fiber Filament Yarn Test Method 8.5.1.
However, the twist coefficient K = 100 before the measurement so as to eliminate the disorder of the single fibers and apply stress to each of the single fibers constituting the yarn.
The measurement was performed with a twist of 0 added. Snar index: Measured according to JIS L 1095: 1999 General spun yarn test method, 9.7.2B method.

Example 1 A limiting oxygen index of 29, a thermal decomposition point of 537 ° C., a tensile strength of 2.03 N / tex and a tensile modulus of 4
9.9 N / tex, 10 single yarns with fineness of 0.167 tex
Using a polyparaphenylene terephthalamide fiber filament yarn (trade name: Kevlar) manufactured by Toray Dupont Co., Ltd. having a fineness of 167 tex and having a bundle of 00 bundles, a ring twisting machine (composite twisting machine manufactured by Kakigi Seisakusho Co., Ltd.) After adding a first twist corresponding to a twist coefficient K = 6308 by type KCT), heat treatment with saturated steam at 180 ° C. was performed for 30 minutes. Next, a second twist was applied in a direction opposite to the first direction by the twisting machine and untwisted until the number of twists became 0, to obtain a crimped yarn according to the present invention. The physical properties of the crimped yarn were measured.

Examples 2 and 3 and Comparative Examples 1 and 2 Using the same yarn type as in Example 1 except that the twist coefficient of the first twist added to the yarn is the value shown in Table 1. Heat treatment with saturated steam, twisting, and untwisting were performed in the same manner. As a result, the physical properties of the obtained crimped yarn were measured. In addition, the value of the twist coefficient in Examples 2 and 3 was within the preferred range of the present invention, while the value of the twist coefficient in Comparative Examples 1 and 2 was selected to be lower than the preferred range of the present invention.

Example 4 Using a yarn of the same material as in Example 1 except that the fineness was 22.2 tex, a first twist corresponding to a twist coefficient K = 5277 was added to the yarn, and the temperature was adjusted to 180 ° C.
For 30 minutes and then untwisted to obtain a crimped yarn according to the present invention. Similarly, its physical properties were measured. Table 1 summarizes the results of Examples 1 to 4 and Comparative Examples 1 and 2. FIG. 1 shows the relationship between the twist coefficient before the heat treatment with saturated steam and the expansion / contraction rate which is a typical characteristic of the crimped yarn. As shown in the table and the figure, the crimped yarns of Examples 1 to 4 have a sufficient stretchable elongation as crimped yarns, whereas Comparative Examples 1 and 2 have a low degree of twist before treatment and have a poor stretchable elongation. It is not suitable for practical use.

[0036]

[Table 1]

[Examples 5 to 7 and Comparative Example 3] The twist coefficient of the first twist added to the yarn is K = 8258,
The time of the saturated steam treatment was 7.5 to 6 as shown in Table 2.
Except for 0 minute, exactly the same as in Example 1,
A heat-resistant crimped yarn according to the present invention was obtained. As Comparative Example 3, the same yarns as those of Examples 5 to 7 were used, the same twist was applied, and the yarn was untwisted after standing at room temperature for 1 day without performing the saturated steam treatment, and the physical properties were measured. Table 2 summarizes the results. FIG. 2 shows the relationship between the processing time and the expansion / contraction rate.
Shown in Examples 5 to 7 and Example 2 and Comparative Example 3
It can be seen from Table 2 that there is no change in the stretch ratio when the treatment time is 7.5 minutes or longer, and that the heating time for obtaining the heat-resistant crimped yarn according to the present invention is short enough.

[0038]

[Table 2]

[Examples 8 to 10 and Comparative Examples 3 and 4] As shown in Table 3, the twist coefficient of the first twist added to the yarn was K = 8258, and the steam temperature during the saturated steam treatment was as shown in Table 3. A heat-resistant crimped yarn according to the present invention was obtained in exactly the same manner as in Example 1 except that the temperature was 130 to 200 ° C. In Comparative Example 4, a crimped yarn was obtained in exactly the same manner as described above except that the steam temperature during the saturated steam treatment was 120 ° C. The results are shown in Table 3 together with Example 2 and Comparative Example 3. FIG. 3 shows the relationship between the processing temperature and the expansion / contraction rate. From this, it is understood that the temperature condition of the saturated steam treatment is preferably 130 ° C. or more for the production of a practical crimped yarn.

[0040]

[Table 3]

[Examples 11 to 14, Comparative Examples 5 and 6] Using the same yarn as in Example 1, twists having a twist coefficient shown in Table 4 were added by a ring twisting machine, and the twisted yarn was put into a hot air dryer. Dry heat treatment was performed under the conditions shown in Table 4. Next, a second twist was applied by the twisting machine in a direction opposite to the first direction and untwisted until the number of twists became 0, thereby obtaining a heat-resistant crimped yarn according to the present invention. Comparative Example 5 was performed in the same manner as in Example 11 except that the temperature during the dry heat treatment was 130 ° C. Comparative Example 6 was performed in the same manner as in Example 12, except that a twist having a twist coefficient K = 4846 was added. Table 4 shows the results. FIG. 3 shows the relationship between the processing temperature and the expansion / contraction rate. In the tested range, in both the production method using high-temperature and high-pressure steam and the production method using dry heat treatment, the higher the heat treatment temperature, the higher the stretchability of the obtained crimped yarn. Further, under the above conditions, a crimped yarn having a higher expansion / contraction rate was obtained by using the high-temperature and high-pressure steam treatment than by using the dry heat treatment. In Comparative Example 5, since the temperature at the time of the dry heat treatment was as low as 130 ° C., the obtained crimped yarn had a slightly lower expansion / contraction rate. Therefore, it was found that the temperature during the dry heat treatment is preferably 140 ° C. or higher. On the other hand, in Comparative Example 6, since the number of twists of the first twist was small, the stretchability of the obtained crimped yarn was slightly low. Therefore, it was found that the first twist preferably has a twist coefficient of 5,000 or more.

[0042]

[Table 4]

Example 15 A yarn of the same material as in Example 1 except that the fineness was 22.2 tex was twisted at 1850 turns / m (twist coefficient K = 8775) with an Italian twisting machine. A weight of 500 g was wound around a bobbin with an aluminum collar. Twisting directions S and Z each produced the same number of cheeses. Put this in a sealed container for saturated steam treatment,
A saturated steam treatment was performed at 80 ° C. for 30 minutes. After cooling, reverse twisting was performed with an Italian twisting machine until the number of twists became 0, to obtain a heat-resistant crimped yarn according to the present invention. The stretch ratio of the obtained crimped yarn was 17.1%. Since this crimped yarn has a small amount of torque remaining, crimped yarns having different residual torques of S and Z are aligned to cancel out the torque, and a total of 88 tex yarns are combined with an SFG-10G seamless glove knitting machine (Shima Seiki Co., Ltd.) And gloves for working according to the present invention. The resulting work gloves are difficult to cut (Cut protec
action performance) was 6.8 N as measured according to ASTM F1790-97. On the other hand, for comparison, a commercially available wooly polyester filament yarn 16.5 tex was used instead of the heat-resistant crimped yarn according to the present invention.
Gloves were knitted in exactly the same manner as described above using a yarn having a total of 99 tex by aligning six (48 filaments, single filament, manufactured by Toray Industries, Inc.), and measuring the difficulty in cutting in the same manner as above. However, it was 3.5N. Thus, the gloves according to the present invention were found to be excellent in difficulty in cutting. The resulting work gloves are composed of crimped yarn, so they are less likely to have fluff than gloves made of Kevlar spun yarn, and handle thin parts because they are thin and stretchy. Easy to use. Therefore, these gloves are effective for soldering electronic components, assembling in a clean room, or in the painting process of aluminum building materials, home appliances or automobiles, and preventing injuries due to burns and sharp parts. It is.

Example 16 500 g of a twisted yarn having the same yarn and the same twisting conditions as those of Example 15 was wound up on an aluminum bobbin, treated with high-temperature and high-pressure water at 180 ° C. for 10 minutes, and then cooled, dehydrated and dried. Then, in the same manner as in Example 15, the heat-resistant crimped yarn according to the present invention was obtained by performing reverse twisting with an Italian twisting machine until the number became zero. The stretch rate of the obtained crimped yarn was 18%. In addition, there was no twist unevenness and the uniformity was excellent.

Example 17 500 g of a twisted yarn having the same yarn and the same twisting conditions as those of Example 15 was wound on an aluminum bobbin, treated with a hot-air dryer at 250 ° C. for 30 minutes, and then cooled naturally. In the same manner as in the above, reverse twisting was performed using an Italian twisting machine until the number became zero, and a crimped yarn was obtained. Although the stretch ratio of the obtained yarn was 12%,
The heat transfer to the inside of the winding layer of the bobbin was not sufficient, and there was a twist set uneven portion. The stretch / elongation ratio of the portion was low, and the crimp unevenness was excessive, and the crimped yarn was not practically usable. However, the above problem was solved by reducing the bobbin winding thickness by half. Thus, in the dry heat treatment, when the yarn layer of the bobbin is thick, the crimp unevenness due to the heat treatment unevenness is likely to occur.
When producing the crimped yarn according to the present invention by using the dry heat treatment, it is preferable that the winding thickness of the bobbin is not too large.

Example 18 A false twist device was provided between a heating zone having a length of 10 m and an air cooling zone having a length of 5 m, and the number of twists of yarn passing through both zones was 1760 turns / m (twist coefficient K = 8258). The heat-resistant crimped yarn according to the present invention was continuously obtained by a so-called false twisting method in which twisting was performed in a heating zone, and twisting was performed in an air cooling zone. Para-aramid fiber Kevlar 22Tex which is a yarn of the same material as in Example 1 except that the fineness is 22 tex as the raw yarn
Was used. The heating zone was heated to 300 ° C., and the yarn feeding speed was 10 m / min. The physical properties of the obtained heat-resistant crimped yarn are as follows: the stretch ratio is 12.5%;
2.6%, crimped yarn fineness 22.9 tex, strength 0.9
It was 6 N / tex.

Example 19 Since the crimped yarn of the para-aramid fiber Kevlar obtained in Example 18 has a small amount of torque remaining, the crimped yarns having different residual torques S and Z are aligned to obtain a torque. And supplied to Shima Seiki's 13 gauge seamless glove knitting machine to obtain a thin glove. This glove has the following advantages, unlike a glove made of spun yarn. 1) Good workability because it has elasticity and fits well to the hand and does not hinder hand movement. 2) It is suitable for work in an environment where dust is not allowed, such as in a clean room, because the fluff is not easily formed.

Example 20 The same number of twists as 640 t / m (twist) was applied to the filament yarn of the same polyparaphenylene terephthalamide fiber (manufactured by Du Pont-Toray Co., Ltd., trade name: Kevlar) using a ring twisting machine. Coefficient 827
0), wound on a bobbin made of aluminum, subjected to high-temperature and high-pressure steam treatment, and then untwisted with a ring twisting machine until the number of twists becomes zero, and the heat-resistant crimped yarn according to the present invention is obtained. I got High temperature and high pressure steam treatment temperature is 200
℃, treatment time was 15 minutes.

[Examples 21 to 24] Instead of polyparaphenylene terephthalamide fiber, in Example 21, polyparaphenylene terephthalamide fiber [high elasticity type]
(Product name: Kepler 49, manufactured by Dupont Toray)
In Example 22, copolyparaphenylene-3,4'-
Oxydiphenylene terephthalamide fiber (manufactured by Teijin Limited, trade name: Technora), a wholly aromatic polyester fiber (manufactured by Kuraray Co., Ltd., trade name: Vectran) in Example 23, and a polybenzobisoxazole fiber in Example 24 A heat-resistant crimped yarn according to the present invention was obtained in the same manner as in Example 20, except that Toyobo Co., Ltd., trade name: Xylon was used. However, as shown in Table 5, the twist added to the filament yarn was changed to a different number of twists from that of Example 20.

Example 25 Using a yarn having a finer size (22.2 tex) than Example 20, the number of twists per unit length of twist added to the filament yarn was 1600 t /
m (see Table 5), and the same procedure as in Example 20 was repeated, except that instead of the ring twisting machine, twisting and untwisting were performed using a double twister suitable for twisting when the number of twists was large. A heat-resistant crimped yarn according to the invention was obtained.

[Example 26] A yarn made of polymetaphenylene isophthalamide fiber having a fineness of 22.2 tex (trade name: Nomex, manufactured by DuPont) was used instead of the polyparaphenylene terephthalamide fiber. In the same manner as in Example 25, a heat-resistant crimped yarn according to the present invention was obtained.

Table 5 shows the physical properties of the heat-resistant crimped yarns obtained in Examples 20 to 26. In Table 5, the tensile strength, tensile modulus, thermal decomposition point, critical oxygen index, and fineness of the original yarn indicate physical properties of the filament yarn before being processed into a crimped yarn. As a result, no matter which of the tested fibers was used, the elongation at stretch indicating the degree of crimp was 8.5% or more. In particular, polyparaphenylene terephthalamide fibers and copolyparaphenylene-3,4'-oxydiphenylene terephthalamide fibers which are para-aramid fibers, polymetaphenylene isophthalamide fibers which are meta-aramid fibers, and wholly aromatic polyester fibers are high. The expansion and contraction rate was shown. Among them, the expansion and contraction rate of polymetaphenylene isophthalamide fiber, which is a meta-aramid fiber, is 104.6%, and has a high crimping property comparable to the expansion and contraction rate of generally used general-purpose fiber crimped polyester. there were.

[0053]

[Table 5]

Example 27 Polyparaphenylene terephthalamide fiber (trade name, manufactured by Du Pont-Toray Co., Ltd.)
Kevlar) 22.2 tex filament yarn 1
The book was supplied to a circular knitting machine in which a total of 150 knitting needles were arranged in a circular shape having a diameter of 91 mm, and a tubular knitted fabric of knitted fabric was prepared. This was treated with saturated steam at 200 ° C. for 15 minutes. Then, the knitted fabric was allowed to cool naturally, and then the knitting yarn was unwound from one end of the knitted fabric. The unwound yarn is a crimped yarn in which the knitting shape is stored. The stretch ratio of the crimped yarn is 35.
%, And the elastic modulus was 56%.

Example 28 A tubular knitted fabric of a knitted structure was prepared in the same manner as in Example 27, using a filament yarn made of polymetaphenylene isophthalamide fiber (trade name: Nomex, manufactured by DuPont). . The knitted fabric was heated in a hot air drier at 200 ° C. for 0.5 minutes. Subsequently, the knitted fabric was allowed to cool naturally, and then the knitting yarn was unwound from one end of the knitted fabric to produce a crimped yarn. The tensile strength and lightness of the obtained crimped yarn were measured. The tensile strength was 200 mm between the grips and the pulling speed was 200 m.
It was measured with a constant speed tensile tester at m / min. The lightness was measured with an SM color computer manufactured by Suga Test Instruments Co., Ltd.

[Examples 29 and 30 or Comparative Examples 7 and 8]
Except that the heat treatment was performed at the temperature shown in Table 6, the same procedure was performed as in Example 28. In Examples 29 and 30, heat treatment was performed within the preferred temperature range of the present invention, and in Comparative Examples 7 and 8, heat treatment was performed at a temperature higher than the preferred temperature range of the present invention. Table 6 shows the results. FIG. 4 shows the relationship between the temperature during the dry heat treatment and the tensile strength, and FIG. 5 shows the relationship between the temperature and the brightness during the dry heat treatment. As is clear from FIG.
A decrease in tensile strength was observed from 350 to 400 ° C. In addition, as is apparent from FIG.
, The lightness of the meta-aramid fiber was changed from brown to brown.

[0057]

[Table 6]

[0058]

The heat-resistant crimped yarn according to the present invention has excellent properties such as heat resistance and flame retardancy inherent in heat-resistant and high-performance fibers, as well as excellent properties which cannot be obtained with conventional filament yarns and spun yarns. It has a stretchable elongation and a stretched elasticity and excellent appearance. In addition, there is substantially no deterioration in quality such as a decrease in strength, a change in color tone, fluffing or breakage due to heat treatment at the time of production. Therefore, if the heat-resistant crimped yarn according to the present invention is used, it is possible to impart not only heat resistance and flame retardancy but also elasticity to the textile product. For example, when the textile product is a clothing product such as gloves or work clothes, It fits well with the body such as hands, and the workability and activity when wearing the fiber product are remarkably improved, and the wearing feeling is also excellent. Further, the heat-resistant crimped yarn according to the present invention hardly generates fluff and dust. Therefore, it is possible to provide useful textile products, particularly work clothes and gloves, in assembly work in a clean room in the precision machine industry, the aircraft industry or the information equipment industry, or in the painting work in the production of aluminum building materials, home appliances or automobiles. .

The method for producing a heat-resistant crimped yarn according to the present invention is characterized in that heat setting is performed by high-temperature high-pressure steam treatment or dry heat treatment. Here, in the high-temperature and high-pressure steam treatment, heat setting can be performed only by maintaining a predetermined temperature for a short time using a conventional facility such as a pressure-resistant closed vessel.
The dry heat treatment can be usually performed under normal pressure, and a continuous process is also possible. Therefore, both are production methods advantageous in production equipment, process management, cost, and productivity.
In addition, since the heat setting is performed at a temperature lower than the decomposition start temperature of the heat-resistant and high-performance fiber, the deterioration of the yarn during heating can be avoided as much as possible.

[Brief description of the drawings]

FIG. 1 shows a relationship between a twist coefficient before a saturated steam treatment and an expansion / contraction rate which is a typical characteristic of a crimped yarn.

FIG. 2 shows the relationship between processing time and expansion / contraction rate.

FIG. 3 shows a relationship between a processing temperature and an expansion / contraction rate.

FIG. 4 shows the relationship between the temperature during dry heat treatment and the tensile strength.

FIG. 5 shows the relationship between temperature and brightness during dry heat treatment.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) D04B 1/28 D04B 1/28 (72) Inventor Kazuhiko Kosuge 1-5-6 Nihonbashi Honcho, Chuo-ku, Tokyo Toray Dupont Co., Ltd. (72) Inventor Takeshi Hatano 1-5-6 Nihonbashi Honcho, Chuo-ku, Tokyo Toray Dupont Co., Ltd. (72) Inventor Mitsuhiko Tanahashi 3-2-2, Hakusancho, Gifu City, Gifu Prefecture No. 3 Fujiwa City Homes Shin Gifu 1002 (72) Inventor Iori Nakabayashi 1-1-1, Oe, Otsu-shi, Shiga Pref.

Claims (14)

[Claims] 1. A heat-resistant and high-performance fiber having a single-fiber fineness of 0.02 to 1 tex, a stretchable elongation of 6% or more, a stretchable elasticity of 40% or more, and a strength of 0.15 to 3.5 N / tex.
A heat-resistant crimped yarn having no deterioration in quality due to heating. 2. The heat-resistant and high-performance fiber is a para-aramid fiber,
2. A wholly aromatic polyester fiber or a polyparaphenylene benzobisoxazole fiber having a strength of 0.5 to 3.
The heat-resistant crimped yarn according to claim 1, wherein the heat-resistant crimped yarn is 5 N / tex. 3. The heat-resistant crimped yarn according to claim 2, wherein the para-aramid fiber is a polyparaphenylene terephthalamide fiber. 4. The heat-resistant crimped yarn according to claim 1, wherein the heat-resistant and high-performance fiber is a meta-aramid fiber and has an expansion and contraction rate of 50 to 300%. 5. The heat-resistant crimped yarn according to claim 4, wherein the meta-aramid fiber is a polymetaphenylene isophthalamide fiber. 6. A bulky and stretchable fiber product comprising the heat-resistant crimped yarn according to claim 1 at 50% or more of a fiber portion. 7. Gloves, firefighting suits, racing suits for automobile racing, racing suits for use in the precision machine industry, aircraft industry, information equipment industry, automobile industry, electric appliance industry, medical operation or hygiene field, or for steel making, welding 7. A bulky and stretchable textile product according to claim 6, which is a workwear for painting. 8. After adding twist to the heat-resistant and high-performance fiber yarn,
A method for producing a heat-resistant crimped yarn, comprising performing heat setting by high-temperature high-pressure steam or high-temperature high-pressure water treatment, and then untwisting the twist. 9. The twist added to the heat-resistant high-performance fiber yarn has a twist coefficient K5,000 to 11,0 represented by the following formula:
The method for producing a heat-resistant crimped yarn according to claim 8, wherein the high-temperature and high-pressure steam or the high-temperature and high-pressure water treatment is performed at a temperature of 130 to 250 ° C. K = t × D ^1/2 [where t represents the number of twists (times / m) and D
Represents fineness (tex). ] 10. After the twist is added to the heat-resistant and high-performance fiber yarn, heat setting is performed by a dry heat treatment at a temperature equal to or lower than the decomposition start temperature of the heat-resistant and high-performance fiber, and then the untwisting of the twist is performed. A method for producing a heat-resistant crimped yarn. 11. A heat-set high-performance fiber yarn is subjected to a heat treatment by a dry heat treatment at a temperature of 140 to 390 ° C. The method for producing a heat-resistant crimped yarn according to claim 10, wherein the twist is untwisted. K = t × D ^1/2 [where t represents the number of twists (times / m) and D
Represents fineness (tex). ] 12. A knitted fabric made of heat-resistant and high-performance fiber yarns, and the knitted fabric is subjected to dry heat treatment or high-temperature / high-pressure steam or high-temperature / high-pressure water treatment, and then the knitted fabric is deknitted. Method for producing crimped yarn. 13. A method of preparing a knitted fabric from heat-resistant and high-performance fiber yarns, treating the knitted fabric with high-temperature high-pressure steam or high-temperature high-pressure water at 130 to 250 ° C. for 2 to 100 minutes, and then knitting the knitted fabric. The method for producing a heat-resistant crimped yarn according to claim 12, wherein: 14. The heat-resistant fabric according to claim 12, wherein a knitted fabric is prepared from heat-resistant and high-performance fiber yarns, dried and heat-treated at a temperature of 140 to 390 ° C., and then the knitted fabric is deknitted. A method for producing a flexible crimped yarn.