JPS61179389A - Thermally discoloring fiber - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION A) Object of the Invention Industrial Application The present invention relates to a thermochromic fiber whose color changes reversibly depending on temperature.

The thermochromic fiber of the present invention includes yarn, cotton, woven fabric, knitted fabric,
It can be easily processed into pile fabrics, non-woven fabrics, etc., and can be used as a basic material for all kinds of textile processing, such as clothing, bedding, interior goods, and toys.

■Conventional technology Conventionally, regarding threads that change color due to temperature changes,
1-2582 discloses an application example of liquid crystal ink. This invention is characterized in that one or both sides of a sheet-like dark colored base material such as black or dark blue is coated with liquid crystal ink to form a flat yarn, or the flat yarn is wound around a core yarn to form a twisted yarn. Therefore, this thread is rather a sheet with a unique shape different from that of ordinary fibers, and the degree of freedom in shape and properties is restricted, making it impossible to take a variety of shapes depending on the purpose.

Furthermore, since the liquid crystal itself is used, its moisture resistance is extremely poor.
It cannot be washed at all, only one color is based on a dark color, it is not possible to freely obtain the color change temperature, and it is expensive and has not been put into practical use. To explain this sheet a little more, even if there is a discoloration layer on both the top and bottom sides, there is no discoloration layer on both the left and right cross sections, and if the sheet is made thin, the discoloration layer will be reduced to less than ]/2 of the total surface, and the discoloration effect will be reduced. It has the drawback of being extremely bad, so it has not been put into practical use. Therefore, there has been a strong desire for fibers that can change color at any temperature and that can change colors in a variety of ways.

■Problems to be Solved by the Invention The present invention completely eliminates the above-mentioned limitations and provides a thermochromic fiber that can be applied to all kinds of textile products.

(b) Structure and effect of the invention ■ Means for solving the problem The present invention provides a method for solving the problem by applying the following formula % on the surface of each elementary fiber [r: particle size of pigment, D: denier number of elementary fiber, d: elementary fiber] The present invention relates to a thermochromic fiber provided with a thermochromic layer comprising a thermochromic pigment and a binder having a particle size that satisfies the specific gravity of the fiber.

In the present invention, in order for the fiber to exhibit a good and uniform thermochromic effect, the particle size of the pigment satisfies r≦1of7r [r: particle size of pigment, D: denier number of elementary fiber, CL: specific gravity of elementary fiber]. It is necessary to do so. In the present invention, since each elementary fiber is independent, the distribution of the thermochromic pigment to the fiber is uniform, and as a result, the fiber has a good texture and is characterized by uniform thermochromic properties. For this purpose, the particle size of the pigment must be within a specific range. According to research by the present inventors, the uneven discoloration of fibers coated with thermochromic pigments is due to uneven distribution of the pigment, and this uneven distribution causes cross-linking of the pigment across multiple fibers. It was discovered that this was due to a number of factors. In other words, depending on the particle size and the thickness of the elementary fibers, when the pigment binds multiple elementary fibers together in a bridge-like manner, there is a tendency for a large amount of the thermochromic pigment to gather in this area.
As a result, the pigment distribution becomes uneven, resulting in uneven thermal discoloration. Since uneven discoloration is caused by a cross-linking phenomenon, it cannot be prevented simply by regulating the particle size of the pigment, and the relationship with the thickness of the elementary fibers becomes an important issue. Based on this new knowledge, the present inventors conducted research to solve the conventional problems, and found that if the relationship of 1510 g between the pigment and the basic fibers was satisfied, the above-mentioned phenomenon could be prevented, and uneven discoloration could be prevented. That's what I did.

Another feature of the present invention is that a thermochromic layer made of a pigment and a binder is provided on the surface of each individual fiber of the fiber. Because the thermochromic layer is provided on the surface of each individual fiber, the distribution of the thermochromic pigment throughout the fiber is uniform, and the texture, flexibility, and pigment adhesion strength are uniform throughout. This new structural unit is a novel thermochromic fiber that has not been previously known. For example, the material described in the above-mentioned Japanese Patent Publication No. 51-2582 cannot provide a thermochromic layer on the entire surface. Therefore, the flocculent material, yarn, etc. made of this basic fiber are novel products that exhibit uniform thermochromic properties, texture, and pigment adhesion strength.

In the present invention, the specific relationship between the thickness of the elementary fiber and the particle size of the thermochromic pigment is particularly determined by r≦](1/”E7T [r:
The particle size of the pigment, D: denier number of the elementary fiber, d: specific gravity of the elementary fiber] is defined by the cross-sectional shape of the elementary fiber, which may have an irregular shape such as a polygonal shape or a flattened shape.

In order to prevent the bridging phenomenon of pigment particles, it is meaningless to simply specify the wire diameter of the elementary fiber and the particle diameter of the pigment. This configuration is required.

The thermochromic layer in the present invention has a weight of 8 s to 9 s to the basic fiber.
0% by weight is appropriate, and 5% to 70% by weight is particularly suitable from the viewpoint of thermochromic discoloration effect.The reason for this is as follows after examining the amount of adhesion. This is because it has become. That is, if it is less than 3% by weight, the texture is good, but the density is low and the color change is not clear, so it is not practical as a fiber. In addition, when the amount of coating exceeds 90% by weight, the concentration is high and the color change is clear, but binding between elementary fibers occurs and it is difficult to make each elementary fiber exist independently. Since the texture is impaired and the soft feel cannot be obtained, it is not of practical use as a fiber.

Therefore, the range of 3% to 90% by weight is a practical range that satisfies both the clarity of the two-color change in density and the soft texture. Furthermore, in the range of 5% to 70% by weight, the density 9 color change is sufficiently clear, and there is no binding between elementary fibers, allowing each fiber to exist completely independently. , a thermochromic fiber of the best quality is obtained, which exhibits a very soft texture and a sufficient balance of pigment adhesion strength. Because it uses a thermochromic pigment with a particle size suitable for the denier of the basic fibers, it has extremely excellent performance in uniformity, flexibility, texture, abrasion resistance, washability, and processability, and is therefore suitable for all types of textile products. It can be applied to

As the thermochromic pigment used in the present invention, conventionally known reversible thermochromic materials made of a combination of an electron-donating color former and an electron-accepting color developer are effective. ]-44706, Japanese Patent Publication No. 51-44707, Japanese Patent Publication No. 51-44708, Japanese Patent Publication No. 51-8
The thermochromic material disclosed in Japanese Patent No. 5216 can be mentioned.

For example, h) electron-donating color formers, (b) compounds having phenolic hydroxyl groups and their metal salts, aromatic carboxylic acids and aliphatic carboxylic acids having 2 to 5 carbon atoms, carboxylic acid salts, acidic phosphoric esters, their metal salts, ], 2.
8-) Electron-accepting color developer such as lyazole and its derivatives, tetrahydrin compounds, (c) Alcohols, esters, ketones, ethers, acid amides, carbon number 6
Thermochromic pigments made of color change temperature regulators such as the above aliphatic carboxylic acids, thiols, sulfides, disulfides, sulfoxides, and sulfones are used.

To give a concrete example, Table 11 is Nodosa'SoZ'J.

These thermochromic materials are approximately -80°C to +100″C
At temperatures between red, blue, yellow til + orange, purple, brown, black, and other combinations, subtle colors can be changed reversibly and instantly from colored to colorless, and from colorless to colored. Agents can also be added to increase the brightness of the white in the neutral and further enhance the contrast. Furthermore, one color can be changed from one color (1) to another new color (1) by adding and using colored compounds such as general dyes, fluorescent dyes, pigments, fluorescent pigments, and monochrome pigments. It is effective because it can be changed. It can also transmit light! It can be made transparent according to a one-degree change, revealing the underlying layer. To turn these thermochromic materials into pigments, the thermochromic materials are encapsulated in microcapsules, blended with various resins, emulsified and then cured, or sprayed and then cured or solidified using a spray drying method, and then pulverized after curing. It can be made into fine particles.

When this pigment is coated on the fiber surface, thermochromic fibers that change from colored to colorless depending on temperature changes are formed.Using this process, thermochromic fibers that change from colored to colored (1) are created. To do this, a thermochromic pigment that is obtained by adding a colored component to a thermochromic composition and that changes from colored (1) to colored (1) is coated on the surface of the bare fibers, or the surface of the fiber is changed from colored to colorless. Thermochromic pigments and general pigments, fluorescent pigments, phosphorescent pigments, dyes, and fluorescent dyes are encapsulated into two particles and coated on the surface of the basic fibers, or colored with general dyes or general pigments. The surface of the base fibers may be coated with a colored or colorless thermochromic pigment. Alternatively, a method such as blending a basic fiber coated with a thermochromic pigment that changes between colored and colorless with a basic fiber colored with general dyes or general pigments may be used.

As the binder for binding the obtained thermochromic pigment to the basic fibers, conventionally known waxes, low melting point thermoplastic resins,
Examples include rubber, natural resin, synthetic resin, and the like. For example, low molecular weight gellyethylene, low melting point polyester, ethylene-vinyl acetate copolymer.

Chlorinated rubber, polyvinyl acetate emulsion, polyethylene emulsion, acrylic emulsion, styrene resin emulsion, butadiene-nitrile emulsion,
Contains shellac, zein, unsaturated finish/l [i, epoxy resin, cellulose resin, polyurethane resin, phenol W resin, hinyl am chloride, vinyl acetate resin, silicon resin, polyvinyl alcohol, zarivinyl methyl ether, etc. .

Single fibers of various materials and shapes are effective, specifically natural fibers, semi-synthetic fibers, and synthetic fibers.

Other chemical fibers such as copolymer fibers, and inorganic fibers.

Examples include materials such as metal fibers, and further examples include cotton,
Wool, goat hair, camel hair, rabbit hair, #I.

Natural silk thread, casein fiber, soy protein fiber, zein fiber, peanut protein fiber, regenerated silk thread, viscose rayon, #I ammonia rayon, saponified acetic acid +-), natural a rubber fiber, alginate fiber, acetate fiber, triacetate fiber , acetylated staple fiber, ethyl cellulose IIIm, m rubber fiber, zaryamide fiber, polyester fiber, polyurethane fiber, polyethylene fiber, poly1o pyrene fiber, polyvinyl chloride fiber, polyvinylidene chloride fiber, polyfluoroethylene type fiber,
l Liacrylonitrile fiber, polyvinyl alcohol a
fiber m, promix fiber, benzoate fiber, voliclar fiber, polynosic fiber.

Acrylonitrile-alkylvinylpyridine copolymer fiber, acrylonitrile-vinyl chloride copolymer fiber, vinyl chloride copolymer fiber, vinyl chloride-vinylidene chloride copolymer fiber, vinyl chloride-vinyl acetate copolymer fiber, vinyl chloride-vinyl acetate copolymer fiber , vinyl chloride-acrylic nitrile copolymer fiber, hinyl chloride-ethylene copolymer fiber, glass fiber, rock wool, ceramic fiber, carbon fiber, and the like.

In addition to the 9 normal fiber Im shapes, the shapes are triangular,
Pentagon, hexagon, Y shape, L shape, house shape, dog bone shape,
Horseshoe-shaped, uneven cross-section fibers, macaroni-like, lotus root-like, spongy9. Hollow fibers such as field shape, side, pie, side type, sheath.

Examples include conjugate fibers such as core type and matrix type 9. Irregular cross-section fibers and hollow fibers have a large surface area and are easy to adhere to pigments, so they have the characteristic that they can be highly concentrated.

Thermochromic fibers coated with thermochromic pigments are produced by the following method, which varies slightly depending on the form of the fiber. first,
Thermochromic elementary fibers are produced by immersing the target strand Jl (which may be crimped if necessary) in a coating composition consisting of a thermochromic pigment, a binder, and a coloring agent, and then drying it. It can be obtained by a method such as spraying, direct coating, etc., followed by drying, and if necessary, crimping.

Next, the thermochromic raw cotton can be obtained by cutting the thermochromic raw fibers obtained above, which have been crimped as necessary, into appropriate lengths, but the raw cotton to be subjected to this process is coated with the above-mentioned coating. Excess components are removed from the composition using immersion wall centrifugation, roll squeezing, air gun, etc., and then drying is performed, or coating is performed using a brush or roll coater, spraying is performed, and then drying is performed. The zero-order thermochromic yarn, which can be obtained by A method of bundling and twisting a plurality of yarns to make a thermochromic filament yarn, or applying the thermochromic raw cotton to a thermochromic sliver, and then going through a spinning process to make a thermochromic spun yarn.Amount% ~90% by weight, especially 5% by weight
-70% by weight is suitable from the viewpoint of thermochromic color change effect. Further, the thermochromic pigment is suitably contained in the thermochromic layer in an amount of 5% to 80% by weight, particularly 10% to 60% by weight from the viewpoint of the thermochromic discoloration effect.In other words, less than 5% by weight. In this case, the color density is low and the color changes.
1ml! On the other hand, if it exceeds 80% by weight, it is difficult to see a clear decolored state. The range of 1% by weight to 60% by weight is the optimum range in which the balance between density and color change is maintained.

The resin to be applied is appropriately selected from among the binders described above, and if necessary, an antioxidant, an ultraviolet absorber, an anti-aging agent, etc. can be added to further make the thermochromic function permanent.

①Example Next, concrete examples will be shown, but the present invention is not limited thereto. (Boss 1 and wholesaler are trying to avoid W-.

Example] A thermochromic composition consisting of 1M crystal violet lactone, 8 parts of benzyl 4-hydroxybenzoate, and 25 parts of stearyl alcohol was encapsulated by a coacervation method using gelatin/gum arabic. 150g of thermochromic microcapsules with a particle size of 8.
, aqueous two-L/I resin emulsion (solid content approx. 41
%) 450g.

After soaking, take out the sample and dry it at 0°C for 2 minutes.

550 g of thermochromic polyurethane fibers were obtained. The thermochromic fiber exhibits a blue color at temperatures below 58°C, and
When the temperature reached 8°C or higher, it turned colorless, and when the temperature was lowered again to 58°C or lower, the color returned to blue, showing reversible thermochromic properties.

Example 2 Spiro(la-H-benzo[α]xanthenya 12,
1'(8'H)-isobenzofuran) = 8'-
on, 9-(diethylamino)-116, bispheno-
1A2[, 15 parts of myristyl alcohol, stearic acid capric acid/L'IO part encapsulated thermochromic composition by an interfacial polymerization method using an epoxy resin/amine curing agent Particle size 5a satisfying 10 parts 7τ 60g of scrap thermochromic microcapsules, 20g of glycidyl ether type epoxy resin
0g, sprayed with amine curing agent, dried at 80°C for 80 minutes, 86
0 g of thermochromic nylon fiber was obtained.

The above-mentioned thermochromic fiber exhibits a pink color at temperatures below 25°C, changes to colorless at temperatures above 25°C, and returns to pink when the temperature is lowered to below 25°C, exhibiting reversible thermochromic properties. Ta.

Example 8 Spiro[isobenzofuran-1 (8H), 9'-[9H
] A thermochromic composition consisting of bovine santen)-8-one, 1 part of B'=chloro-6'-(diethylamino)-8°-methyl, 2 g of zinc benzoate, and 25 parts of diphenyl ether was mixed with an epoxy resin/amine. 200g of thermochromic microparticles with a particle size of 12μ satisfying r≦104, solidified to the inside with a hardening agent, and 800g of an acrylic ester resin emulsion with a solid content of about 42% were uniformly mixed and dried for a coating period of 1280g. A thermochromic vinyl chloride-vinyl acetate copolymer fiber was obtained.

The above-mentioned thermochromic fiber exhibits a vermilion color at temperatures below 10°C, turns colorless at temperatures above 10°C, and returns to vermilion when the temperature is lowered to below 0°C, exhibiting reversible thermochromic properties. Indicated.

Implementation number Spiro (isobenzofuran-1 (IIH)', 9'-
[9H]xanthine]-8-one, 6'-(diethylamino)-8'-methyl-2'-(phenylamino J-1
K? 4-Chlorobenzoin caB part, stearin amide 25 parts polypropylene? To 509 M - Particle size 4 that satisfies r≦10$ obtained by cooling and pulverizing after crosstalk
After immersing 200 g of thermochromic microparticles of μ-end and g of vinyl acetate-ethylene-vinyl chloride ternary copolymer, take them out and heat them to 100°C.
Dry for 5 minutes.

1080 g of thermochromic fibers were obtained.

The thermochromic fiber exhibits a black color below 95°C,
When the temperature reached 95"C or higher, it turned colorless, and when the temperature was lowered to 95"C or lower, the color returned to black, showing reversible thermochromic properties.

Example 5 1(8H)-isobenzofuranone, 8.8-bis(]-
ethyl-2-methyl-]H-indol-8-yl)-
A thermochromic composition consisting of 1 part bisphenol A subf [2 [2] and 25 g cetyl alcohol is solidified to the inside with an epoxy resin/amine curing agent.Thermal discoloration of the particle diameter axis m satisfying r≦101-Σ1- Acrylic-vinyl acetate copolymer emulsion 70 with 100g of fine particles and solid content of about 45%
5D acrylonitrile-vinyl chloride copolymer flat cross-section elementary fiber 8 in a coating composition uniformly mixed with 0g of
After soaking, take out 00g and cut into 100'' CIG.
880 g of thermochromic acrylonitrile-vinyl chloride copolymer raw cotton was obtained.

The above-mentioned thermochromic raw cotton exhibits a pink color at temperatures below 40'C, changes to colorless at temperatures above 40'C, and returns to pink when the temperature is lowered to below 40'C, exhibiting reversible thermochromic properties. Indicated.

Example 6 A thermochromic composition consisting of 1 part of crystal violet lactone, octyl 4-humanxybenzoate a@, and 25 parts of butyl stearate was encapsulated by an interfacial polymerization method using an acrylic resin/amine curing agent. 100g of thermochromic microcapsules with a particle size of 12Arn that satisfy 71-
, a thermochromic vinyl chloride-vinylidene chloride copolymer obtained by uniformly mixing 650 g of an ethylene-vinyl acetate copolymer emulsion with a solid content of about 50% and crimping it into a coating composition and drying it at 90°C for 15 minutes. 50ff~9 fibers
Bias cutting was carried out at 0ff to obtain 790 g of thermochromic vinyl chloride-vinylidene chloride copolymer raw cotton.
When the temperature reached 0°C or higher, it turned colorless, and when the temperature was lowered to 10°C or lower, the color returned to blue, showing reversible thermochromic properties.

Example 7 1 part of crystal violet lactone, 2 parts of 4.4-methylene diphenol, and 25 parts of stearon were uniformly mixed into 800 parts of polyethylene, cooled, and finely pulverized.
A coating composition in which 800 g of thermochromic microparticles with a particle size of 8IA7'yI satisfying ≦104- and 400 g of an acrylic acid ester emulsion with a solid content of about 45% are uniformly mixed. After removing the excess composition by centrifugation. ]00
After drying for 10 minutes, 650 g of thermochromic polyacrylonitrile raw cotton was obtained.

The above-mentioned thermochromic raw cotton exhibits a blue color at temperatures below 85°C.
When the temperature exceeded C, it turned colorless, and when the temperature was lowered to below 85°C, the color returned to blue, showing reversible thermochromic properties.

Example 8 Spiro[isobenzofuran-1 (8H), 9°-[9H
[Xanthine]-8-one, 8″, 6′-dimethoxy-
] part, dodecyl gallate 2 parts, capryl-〇K
tm y F + z ync &
M-threat are Ml-p-, JJ =
<+-/-y 500g of thermochromic microcapsules with a particle size of about 10μ that satisfy rpl'OMΣGo, encapsulated by the coacervation method using rapia rubber, and 500g of acrylic acid ester resin emulsion with a solid content of about 42%.
The above-mentioned thermochromic cotton exhibits a yellow color at temperatures below 15°C.
When the temperature exceeded C, it turned colorless, and when the temperature was lowered to below 15°C, the color returned to yellow, showing reversible thermochromic properties.

Example 9 Spiro(isobenzofuran-1(8H), 9'-(
9H) Xanthine2-one, 6″-(cyclo)xylamino)-comethyl-2′-(phenylamino)-
A thermochromic composition consisting of 1 part, 2 g of 5,5-bis(],]2,8-benzotriazole, and myristyl alcohol 2581S was encapsulated in acid chloride/phenol by polymerization on the upper 7.R surface.

Particle diameter satisfying r≦1of−Σ]−4. &fi's Thermochromic W Thermochromic polypropylene element obtained by soaking 500 g of small capsules, vinyl acetate-ethylene-vinyl chloride terpolymer emag with approximately 50% solidity, and drying for 6 minutes at 100" C. 80 fibers were bundled and twisted at 80 turns/m to obtain 850 g of thermochromic polypropylene filament yarn.

The thermochromic yarn exhibited a black color at temperatures below 88°C, turned colorless at temperatures above 88°C, and returned to black when the temperature was lowered to below 88°C, exhibiting reversible thermochromic properties.

Example 10 1 (8H-isobenzofuranone, 8-(1-ethyl-2-methyl-IH-indo-8-yl)-8-
(4-diethylaminophenyl)-1 part, naphthoic acid 2
part, Valmitin #I] z, s part, decyl caprylate 12
A thermochromic composition consisting of 65 parts was solidified to the inside with an epoxy resin/amine curing agent, and 60 g of thermochromic fine particles with a particle size of 10 μm satisfying r<IOD/a and 900 g of epoxy resin.

Twenty-five 5D nylon fibers crimped with a coating composition uniformly mixed with 80 g of an amine curing agent were bundled and twisted at 40 turns/m to obtain 850 g of thermochromic nylon thread.

The above-mentioned thermochromic yarn exhibits a blue color at temperatures below -8°C.
When the temperature exceeded this temperature, the temperature changed to colorless, and when the temperature was lowered to below -8°C, the color returned to blue, showing reversible thermochromic properties.

Example 11 Spiro[isobenzofuran-1 (BH), 9″-[9H
[xanthine]-8-one, a'=(diethylamino)
= 1 g of 6',8'-dimethyl, 2 parts of 1.1-bis(4-hydroxyphenyl)-cyclohexane, and 25 parts of dilauryl ether were uniformly mixed into 760 parts of polypropylene, cooled, and finely pulverized. 500 g of thermochromic microparticles with a particle size of 8 cm that satisfy r≦104-, solid content 45%
Acrylic acid ester resin emulsion soogtl!
50 7D polyacrylonitrile spongy hollow fibers crimped in r-mixed coating composition
After soaking, 0g of thermochromic polyacrylonitrile raw cotton was taken out and heated at 100°C for 10 minutes.The obtained thermochromic polyacrylonitrile raw cotton was applied to a card to make a sliver, and then subjected to a spinning process to obtain a spun yarn of 600g of thermochromic polyacrylonitrile hollow fibers. Ta.

The thermochromic spun yarn has an orange color below BO"C, and
When the temperature exceeded 0''C, the color changed to colorless, and when the temperature was lowered to 80C or lower, the color returned to orange, showing reversible thermochromic properties.

Example 12 Spiro[isobenzofuran-1 (8!1), 9'-
(9H) 100g of thermochromic microcapsules with a particle size of 10μ that satisfies OpZl-, in which a thermochromic composition is encapsulated using an interfacial polymerization method using a polyisocyanate/amine curing agent.
Approximately 25% Maryester resin emulsion 500
Remove excess composition evenly with a gun, and heat at 100℃5
The thermochromic polyester raw cotton obtained by drying for minutes was carded to form a sliver, and then subjected to a spinning process to obtain 600 g of thermochromic polyester spun yarn.

The above-mentioned thermochromic spun yarn exhibits a green color at temperatures below -]0°C, turns yellow at temperatures above -10°C, and then returns to 4-10°C.
When the temperature was lowered below, the color returned to green and exhibited reversible thermochromic properties.

Comparative Example 150 g of thermochromic microcapsules with a particle diameter of a oIlm, r > 1 Or, containing the same composition as in Example 1 using gelatin/gum arabic using the core 7 Lebessie method, and an aqueous urethane resin with a solid content of approximately 41%. emulsion 450g
, take out the water-based epoxy and dry for 2 minutes at 0'C.
80 g of thermochromic polyurethane fibers were obtained.

This thermochromic fiber also exhibits a blue color at temperatures below 58°C.
When the temperature reached 58°C or higher, the color changed to colorless, and when the temperature was lowered to 58°C or lower, the color returned to blue, showing reversible thermochromic properties.

Comparative Test 1 When the thermochromic elementary fibers obtained in Example 1 and Comparative Example were bundled and the appearance of Togane body was compared, the fiber bundle obtained in Example 1 showed a uniform blue color, and there was no uneven discoloration at the time of discoloration. However, in the fiber bundles obtained from comparative examples, the blue color was non-uniform, and when the fibers changed color, significant discoloration and unevenness occurred which made them unsuitable for practical use.

Comparative Test 2 Thermochromic textile fabric obtained by bundling 10 thermochromic fibers obtained in Example 1 and Comparative Example and twisting them at 80 times/m to form thermochromic filaments and weaving them on a loom. JxS
When a washing test was conducted in accordance with I, No. 0844A-2, the fabric obtained from Example 1 maintained the same density as the fabric before washing, but the fabric obtained from Comparative Example showed that the pigment did not fall off. Most importantly, the thermal discoloration effect almost disappeared after one wash.

Comparative Test 8 A thermochromic pile fabric with a pile length of 46 m obtained by crimping the thermochromic fibers obtained in Example 1 and Comparative Example, cutting them into 90 fl, processing them into slivers with cards, and then knitting them. When it was subjected to a brushing process and a polyrashing process at the finishing stage, the thermochromic pile fabric obtained from Example 1 maintained the same density as before finishing, was highly flexible and had a very nice texture. However, in the thermochromic pile fabric obtained in the comparative example, the pigments came off due to strong abrasion, and the thermochromic effect almost disappeared.

From the above comparative test results, the particle size r (I
lm) and the denier number of the basic fiber (specific gravity d) is r
It was clearly shown that the relational expression: as+a10FΣ]- is satisfied.

As explained above, the present invention completely eliminates the limitations of thermochromic fibers obtained by coating with conventional liquid crystal inks, and has unprecedented thermochromic properties, flexibility, texture, and scratch resistance. The purpose of this invention is to provide thermochromic fibers that have excellent properties in terms of washability, washability, and processability, and can be applied to all kinds of textile products.

An example of the use of the present invention is shown below.

Shirts, cardigans, vests, sports shirts, polo shirts, dress shirts, T-shirts, blouses, suits,
Bramble. Jackets, slacks, skirts, training wear, jeans/<-9 men's clothing, women's clothing, children's clothing, baby clothing, school uniforms.

Clothing fabrics such as work clothes 1 Kimono, Japanese clothing fabrics such as obi, coats,
Raincoat, gown, pajamas, bathrobe, socks 9
Gloves, underwear, swimwear, chassis, scarves, shawls,
Muffler, hat, earmuffs, slippers, tie, veil, ski wear, tabi, patch, handbag, shade 1. -tlikM rug, towels, handkerchiefs, blankets, sheets, lap hooks.

Futons, futon cotton, carpets, chair upholstery, rugs,
Cushions, moquettes, kotatsu overlays, kotatsu underlays, sheet fabrics, wall covering fabrics, artificial flowers, embroidery, lace, ribbons, curtains, cloths, curtains, carpets, rugs, ropes, canvas, tents, cheesecloth, hoses, canopies, sheets, Climbing shoes, transport bags, lifeboats, rucksacks, wrapping cloth, parachutes, belts, nets, clothes for nine stuffed animals, doll hair, cotton for Christmas trees, false beards, false eyelashes, wigs, hair pieces, Balls, sound-absorbing curtains, heat insulating materials, napkins, lampshades, partition screens, blinds, and more! ! [Can be applied to products.

Claims (1)

[Claims] 1. The following formula r≦10√(D/d) [r: particle size of pigment, D: denier number of elementary fiber, d: specific gravity of elementary fiber] is applied to the surface of each elementary fiber. A thermochromic fiber provided with a thermochromic layer comprising a thermochromic pigment of a satisfactory particle size and a binder. 2. The thermochromic fiber according to claim 1, wherein the thermochromic fiber is a plain fiber. 3. The thermochromic fiber according to claim 1, wherein the thermochromic fiber is raw cotton formed by aggregating elementary fibers. 4. The thermochromic fiber according to claim 1, wherein the thermochromic fiber is a thread made of basic fibers. 5. The thermochromic fiber according to claim 1, wherein the thermochromic pigment comprises a thermochromic material in which an electron-donating color former and an electron-accepting color developer are combined.