JPH11323708A - Reversibly thermally color-changeable braid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject braid with high flexibility and high durability to color change by melt-blending a resin with a pigment including a homogeneously compatibilized mixture comprising an electron-donating and coloring compound, an electron-accepting compound and a reaction medium determining the color reaction-inducing temperature. SOLUTION: This reversibly thermally color-changeable braid having the above-mentioned advantages is obtained by the following process: a microencapsulated pigment including a reversibly thermally color-changeable composition consisting of a homogeneously compatibilized mixture comprising (A) an electron-donating and coloring organic compound, (B) an electron- accepting compound and (C) a reaction medium determining the temperature inducing the color reaction between the components A and B, is melt-blended at 0.1-30 pts.wt. in 100 pts.wt. of a thermoplastic resin, and the resulting blend is then melt-spun using a melt spinning unit to produce a reversibly thermally color-changeable yarn 10-300 μm in outer diameter; subsequently, the yarn is braided using a braider for circular braid.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a reversible thermochromic braid. More specifically, the present invention relates to a reversible thermochromic braid having the same tactile sensation and durability of a thermochromic function as a conventional general-purpose braid.

[0002]

2. Description of the Related Art Conventionally, regarding reversible thermochromic yarns,
Although some proposals have been disclosed, no effective proposal has been disclosed yet for a braid that exhibits a reversible color change due to a temperature change. Further, as a method of manufacturing a braid that exhibits a reversible color change due to a temperature change, the braid is immersed and dyed in a reversible thermochromic material containing a binder resin,
Alternatively, after dyeing the yarn before braiding, braiding or dyeing the fiber in advance, a yarn is created by spinning, and a braid that reversibly changes color by a method such as braiding the yarn is obtained. A method of obtaining a braid exhibiting a reversible color change by a method or a method of providing a reversible thermochromic layer on the surface of the braid by spraying or the like is conceivable. In any of the above-described methods, even if a braid that can reversibly change color due to a temperature change can be obtained, the former method uses a binder resin in a reversible thermochromic material during dyeing or during spinning or braiding after dyeing. Are easy to produce, difficult to manufacture, and the braid made is poor in flexibility. Also, although the latter can slightly maintain the flexibility of the braid, the reversible thermochromic layer does not follow the movement of each yarn due to the bending of the braid, or easily peels off due to friction between the yarns. A problem occurs in that it is difficult to exhibit a desired color change.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a reversible thermochromic braid which is excellent in flexibility and excellent in durability against color change even when used repeatedly.

[0004]

The present invention relates to (a) an electron-donating color-forming organic compound, (b) an electron-accepting compound,
(C) A microcapsule pigment containing a reversible thermochromic composition comprising a homogeneous compatible solution of a reaction medium for determining the temperature at which the color reaction of (a) and (b) occurs is dispersed in a thermoplastic resin. A reversible thermochromic braid braided with a reversible thermochromic yarn formed by melt-blending into a braid.
Further, the reversible thermochromic microcapsule pigment is braided with a reversible thermochromic yarn containing 0.1 to 30 parts by weight in a thermoplastic resin, and the outer diameter of the reversible thermochromic yarn is 10 to 10. It is required that the thickness is 300 μm, that the braid is formed by the reversible thermochromic yarn and the non-thermochromic yarn, and the like.

Examples of the thermoplastic resin forming the reversible thermochromic yarn include polyolefin resins such as low-density polyethylene, linear low-density polyethylene, high-density polyethylene, and polypropylene; polyester resins such as polyethylene terephthalate and polybutylene terephthalate; Examples thereof include polyamide resins such as 6-nylon, 6,6 nylon, 12-nylon, 6-6,6 copolymer nylon, and 6-12 copolymer nylon, and polyvinyl chloride resins.

(B) an electron-donating color-forming organic compound which is melt-blended in a dispersed state in the thermoplastic resin;
Microcapsule pigments containing an electron-accepting compound, (c) a reversible thermochromic composition comprising a homogeneous compatible solution of a reaction medium for determining the temperature at which the color reaction of (a) and (b) occur, have been conventionally used. A known reversible thermochromic composition is encapsulated. Specific examples of the reversible thermochromic composition include JP-B-51-35414 and JP-B-51-44.
No. 706, Japanese Patent Publication No. Sho 51-44708, Japanese Patent Publication No. Sho 52-7776, Japanese Patent Publication No. Hei 1-29398, and Japanese Patent Application Laid-Open No. Hei 7-186546. The color changes before and after a predetermined temperature (discoloration point) as a boundary, and only one specific state can exist in a normal temperature range between the two states before and after the change. That is, the other state is maintained while the heat or cold required for the state to develop is applied, but returns to the state exhibited in the normal temperature range if the application of the heat or cold disappears, so-called, A small hysteresis width (Δ
H) is a type that changes color.

Also, Japanese Patent Publication No. 4-171 proposed by the present applicant.
No. 54, JP-A-7-179777, JP-A-7-179777
The thermosensitive color-changing color memory composition which exhibits large hysteresis characteristics and discolors described in, for example, JP-A-339997, that is, the shape of a curve plotting a change in coloring density due to a temperature change indicates a temperature in a discoloration temperature range. This is a type in which the color changes following a significantly different path between the case where the temperature is raised from the lower temperature side and the case where the temperature is lowered from the higher temperature side than the color change temperature range. A reversible thermochromic composition having a characteristic of being able to memorize and retain a state changed at a temperature lower than the low-temperature side discoloration point or higher than the high-temperature side discoloration point in the normal temperature range is also effective.

The above-mentioned reversible thermochromic composition containing three components of an organic compound medium which reversibly causes a color reaction between the electron-donating color-forming organic compound and the electron-accepting compound is contained in a microcapsule. Used as a pigment. This is because the reversible thermochromic compositions can be maintained under the same composition under the various use conditions and can exert the same effect. By being encapsulated in the microcapsules, a chemically and physically stable pigment can be constituted, and the particle diameter is 0.1 to 100 μm, preferably 1 to 50 μm.
m, more preferably the range of 2 to 30 μm satisfies the practicality. The microencapsulation is carried out by a conventionally known interfacial polymerization method, in situ polymerization method, in-liquid curing coating method, phase separation method from aqueous solution, phase separation method from organic solvent, melting dispersion cooling method, air suspension. There are a coating method, a spray drying method, and the like, which are appropriately selected according to the application. Further, a secondary resin film may be further provided on the surface of the microcapsule according to the purpose to impart durability, or the surface characteristics may be modified for practical use.

[0009] The reversible thermochromic yarn comprising the thermoplastic resin and the microcapsule pigment is prepared by adding a microcapsule pigment together with the thermoplastic resin at the time of spinning, and also preparing a microcapsule in the thermoplastic resin in advance. A yarn can also be obtained by a melt spinning apparatus using a pellet blended with a pigment. Incidentally, the microcapsule pigment,
0.1 to 30 parts by weight, preferably 1 to 10 parts by weight, is contained with respect to 100 parts by weight of the thermoplastic resin to form a reversible thermochromic yarn. If the amount is less than 0.1 part by weight, it is difficult for the reversible thermochromic composition to obtain a desired color density in a colored state,
If the amount exceeds 30 parts by weight, the amount of microcapsule pigment becomes excessive, the non-melting part is present in the thermoplastic resin, the spinnability is reduced, and the melt spinning becomes difficult, and the residual color may be generated in the decolored state. is there. Furthermore, conventionally used light stabilizers, for example, ultraviolet absorbers, antioxidants, antioxidants,
A light stabilizer selected from a singlet oxygen quencher, an ozone decolorizer, a visible light absorber, and an infrared absorber may be appropriately blended, or various plasticizers, general pigments, fluorescent pigments, and white pigments such as titanium dioxide. Also, a colorant such as a pearl pigment or a metal powder or a luminous pigment may be added. Further, the outer diameter of the reversible thermochromic yarn is suitably 10 to 300 μm, preferably 30 to 150 μm, more preferably 50 to 10 μm.
0 μm. The outer diameter of the reversible thermochromic yarn is 300 μm
If the temperature exceeds the limit, the braid obtained by braiding lacks flexibility and has poor thermal conductivity, which may impair the thermochromic function of reversibly developing and erasing colors due to temperature changes. or,
When the outer diameter of the reversible thermochromic yarn is less than 10 μm, the color density at the time of color development is low, and thus the color change of the braid obtained by braiding becomes difficult to visually recognize.

Using the reversible thermochromic yarn formed as described above, a flat type reversible thermochromic braid or a round braid using a braiding machine such as a flat braiding machine or a round braiding braid. Manufacture reversible thermochromic braids. Examples of the form of the braid include forms such as three-strike, four-strike, six-strike, eight-stroke, sixteen-stroke, twenty-four-stroke, and loose-strike.

As the yarn constituting the reversible thermochromic braid, not only a yarn formed by melt-blending the microcapsule pigment in a dispersed state in a thermoplastic resin, but also various non-thermochromic yarns are used in combination. Can also be used. Examples of the non-thermochromic yarn include conventionally known non-thermochromic synthetic yarns and natural yarns, and yarns colored with the coloring agent can also be used.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The reversible thermochromic braid of the present invention is obtained by braiding a reversible thermochromic yarn prepared in advance by a conventionally known method.
Plush toys, doll hair, doll costumes, accessories for dolls such as shoes and bags, toys such as Christmas trees, hagoita, clothes such as dresses, swimwear, raincoats, personal belongings such as handkerchiefs, furoshiki, curtains, Indoor decorations such as curtain strings, table hangings, shoes, shoelaces, hats, bags, stationery, packaging containers, cushions, cushions, pillows, mattresses, picture frames, pants hanging, hair stoppers, ribbons, artificial flowers, various printed materials, It is used for photo stands, bags such as wallets, various tool cases, parasols, bowls, banners, flags and the like.

[0013]

EXAMPLES The reversible thermochromic braid of the present invention will be specifically described by the following examples, but the present invention is not limited by these examples. In addition, the composition in an Example shows a weight part.

Example 1 Preparation of a reversible thermochromic microcapsule pigment 2 parts of 1,2-benz-6-diethylaminofluoran
A reversible thermochromic composition comprising 6 parts of 1,1-bis (4-hydroxyphenyl) -n-octane and 50 parts of stearyl caprate is microencapsulated by an epoxy resin / amine interfacial polymerization method to obtain an average particle diameter. 10-20μ
m of reversible thermochromic microcapsule pigment was obtained. The microcapsule pigment reversibly changes color to a color above 34 ° C. and to a pink color below 28 ° C.

Spinning of reversible thermochromic yarn 10 parts of the above dried and dehydrated microcapsule pigment and 300 parts of polypropylene resin (melt flow 45) are mixed and melt-mixed at 180 ° C. in an extruder for thermochromic discoloration. A functional polypropylene resin was obtained. The resin is 34
The color reversibly changes to white at 28 ° C or higher and pink at 28 ° C or lower. Next, the resin is spun at 180 ° C. from a die having 24 discharge holes using a general-purpose melt spinning device,
By stretching, 24 outer diameters of about 80 μm (4
A multifilament consisting of the reversible thermochromic yarn 0d) was obtained.

Production of thermochromic braid The above-mentioned reversible thermochromic yarn was woven using an eight-punched round lace machine. The reversible thermochromic braid obtained as described above is a braid that exhibits a white color at 34 ° C or higher and a pink color at 28 ° C or lower, and does not impair the thermochromic function even after repeated use. A reversible thermochromic braid satisfying the properties and flexibility was obtained. This change in appearance could be repeated by changing the temperature.

Example 2 A reversible resin having an outer diameter of about 60 μm was prepared in the same manner as in Example 1 except that the polypropylene resin used in Example 1 was replaced with a polybutylene terephthalate modified at 35 mol% isophthalic acid (melting point: 168 ° C.). A thermochromic yarn was obtained. The reversible thermochromic braid made by the same method using the yarn had the same color change, durability and flexibility as in Example 1.

Example 3 In place of the polypropylene resin used in Example 1, 6-1
A reversible thermochromic yarn was obtained in the same manner as in Example 1 except that a 2-copolymer polyamide resin (melting point: 155 ° C.) was used. The reversible thermochromic braid made into a braid by the same method using the yarn had the same color change, durability and flexibility as in Example 1.

Example 4 Using the four reversible thermochromic yarns obtained in Example 1 and four non-thermochromic white polypropylene yarns, an eight-strand braid was formed in a striped pattern. The reversible thermochromic braid obtained as described above had a pink and white stripe pattern at 28 ° C or lower, and a white solid braid at 34 ° C or higher. This change in appearance could be repeated by changing the temperature.

COMPARATIVE EXAMPLE 1 A braid made with an eight-punched round cord tying machine using a nylon thread was immersed in a dyeing solution comprising the microcapsule pigment and an acrylic resin emulsion prepared in Example 1. And
The excess dyeing liquid was squeezed out using a roller, and then dried to obtain a reversible thermochromic braid. The reversible thermochromic braid shows the same color change as in Example 1 due to temperature change, but has poor flexibility because the yarns are bound together, and further impairs the appearance as a braid and has low commercial value. there were.

Comparative Example 2 An acrylic short fiber was immersed and dyed in the same dyeing solution as in Comparative Example 1, and then dried while loosening. A sliver obtained was spun with a spinning machine to obtain a reversible thermochromic yarn. Obtained. The thread was tied with an eight-punched round cord tying machine to obtain a reversible thermochromic braid. Although the reversible thermochromic braid shows the same color change as in Example 1 due to temperature change, the microcapsule pigment is detached at the time of spinning and at the time of braiding, and the quality of the braid is reduced because powder is generated, and Also, the discoloration function of the braid was not sufficient.

[0022]

The reversible thermochromic braid of the present invention exhibits a reversible color change by a temperature change, without losing a soft texture, and satisfies the color changing function and the durability of repeated use. A braid that satisfies practicality and decorativeness can be provided even in various fields requiring endurance.

Claims (4)

[Claims] (1) an electron-donating color-forming organic compound,
(B) an electron-accepting compound; and (c) a microcapsule pigment containing a reversible thermochromic composition comprising a homogeneous compatibilizer of a reaction medium for determining the temperature at which the color reaction of (a) and (b) occurs. A reversible thermochromic braid formed by braiding with a reversible thermochromic yarn formed by melt-blending in a dispersed state in a thermoplastic resin. 2. The reversible thermochromic yarn according to claim 1, wherein the reversible thermochromic microcapsule pigment is contained in an amount of 0.1 to 30 parts by weight with respect to 100 parts by weight of the thermoplastic resin. Thermochromic braid. 3. The reversible thermochromic yarn has an outer diameter of 10 to 30.
The reversible thermochromic braid according to claim 1 or 2, which has a thickness of 0 µm. 4. The reversible thermochromic braid according to claim 1, which is braided by the reversible thermochromic yarn and the non-thermochromic yarn.