JPH0651956B2 - Photo-reversible discoloration fabric - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) In the present invention, the hue of fabric is reversibly changed to dark and light depending on the intensity of light. The present invention relates to a photo-reversible discolorable cloth having excellent light resistance and wash resistance. Here, the photo-reversible discoloration is called the photochromic effect, and when light is irradiated, the hue changes from colorless due to the effect of light of a certain wavelength, and it returns to the original hue when returned to a dark place and left for a while. Say.

(Prior Art) For curtains and some outer garments, when the light irradiation amount is strong, the hue of the fabric is darkened to suppress the light transmission amount, and conversely, when the light irradiation amount is weakened. There is a demand for a fabric that can be lightly colored to increase the amount of light transmission.

Various attempts have hitherto been made to meet such demands. For example, according to the description regarding the prospect of the possibility of chameleon fibers (“Chemical Fiber Monthly Report”, Vol. 28, December 1975, p. 50). As a method for producing chameleon fibers, a method of mixing a compound exhibiting a photoreversible discoloration property during spinning of the fiber (a), coating the fiber surface (c) using it as a dye, and the like are described. . In addition, the present applicant previously proposed in Japanese Patent Application No. 59-246883 a photosensitive resin composition having excellent color-forming property and rapid repetitive color change and reproducibility by using a spironaphthoxazine derivative. In JP-A-60-115656, a photo-reversible discoloration cloth and a method for producing the same were proposed.

It is possible to produce a photo-reversible discoloration fabric by any of these methods, and in particular, in the invention of the above application, a product excellent in color developability and rapid repeatability can be obtained, and light resistance and washing resistance can be improved. However, it is far superior to the conventional technology. However, in the case of the curtain or the cloth for clothing which is the object of the present invention, not only the required performance is excellent in photoreversible discoloration characteristics, but also the characteristics such as durability against sunlight and washing, and quick response are also provided. ，
Furthermore, it should be easy to manufacture. The fact is that a photo-reversible color-changing fabric having these characteristics has not yet been obtained.

(Problems to be Solved by the Invention) The present invention has been made in view of the above situation, and has excellent color development and rapid repeated color change and repeatability, and also has good light resistance and washing resistance. The purpose is to obtain a photo-reversible discolorable cloth.

(Means and Actions for Solving Problems) The present invention provides a fiber cloth with the following general formula (I): (In the formula, R is a lower alkyl group, X ₁ and X ₂ are hydrogen atoms,
Hydroxyl group, lower alkoxy group or halogen atom, X ₃ , X
₄ represents a hydrogen atom, a lower alkyl group, a lower alkoxy group, a halogen atom, a nitro group, or a cyan group. ) The photoreversible discolorable cloth characterized in that the spironaphthoxazine derivative represented by the formula (3) is applied in the form of microcapsules encapsulated as a core substance in a spherical porous hollow inorganic powder. is there.

Hereinafter, the present invention will be described in detail.

The cloth used in the present invention includes nylon 6 and nylon 6
Polyamide synthetic fiber represented by 6, polyester synthetic fiber represented by polyethylene terephthalate, polyvinyl alcohol synthetic fiber, semi-synthetic fiber such as triacetate, nylon 6 / cotton, mixed fiber such as polyethylene terephthalate / cotton, cotton, Examples include woven fabrics, knitted fabrics, non-woven fabrics and the like made of natural fibers such as hemp, wool and silk.

In the present invention, as a photoreversible color-changing compound, a spironaphthoxazine derivative represented by the general formula (I) (hereinafter referred to as compound (I)) is encapsulated in spherical, porous or hollow inorganic powder to form a microencapsulated compound. Use what you did. Compound (I) has excellent color development performance and 1,00
It is a substance having a repeatability of 0 or more times.

The microencapsulation of the compound (I) is carried out by first forming an inorganic shell with spherical, porous, or hollow inorganic powder (see JP-B-57-55454, if necessary), and then keeping it under reduced pressure. It is also possible to perform microcapsulation by injecting an organic solvent saturated solution of the compound (I) into the spherical, porous or hollow inorganic powder described above and then drying.

In the present invention, in view of fluidity of the solution, lubricity and stability when dispersed in the resin solution, the particle size of the powder is 0.1
It is preferably about 10 μm.

In the present invention, since the compound (I) soluble in an organic solvent such as methylene chloride, acetone, and ethanol is dispersed in the resin while being contained in the microcapsules, it is used.
In order to prevent the capsules from breaking in the resin solution, an inorganic material is suitable for the wall material of the Micule capsule.
For example, an alkaline earth metal carbonate such as calcium carbonate or barium carbonate, an alkaline earth metal silicate such as calcium silicate or magnesium silicate, a metal oxide such as iron oxide or silica (anhydrous silica) can be used.

Among the above-mentioned inorganic compounds, the composition of the inorganic powder, which has a composition that absorbs nearly 100% of ultraviolet rays, is important for obtaining the photo-reversible discoloration cloth excellent in light resistance which is the object of the present invention. Is most preferably silica.

The hollow inorganic powder has fluidity in a resin dispersion solution,
From the aspect of lubricity, it is important that the shape is spherical, and a perfect spherical shape is particularly preferable. It is particularly necessary that the hollow inorganic powder be porous and non-cotton or sponge-like. Since the capsule wall is a sponge tissue, the core substance can be contained in the capsule in a solution state, and after that, only the solvent can be expelled from the capsule system.

As a resin binder for adhering the compound (I) to the fiber, a material having a total light transmittance of 65% or more is preferably used in order to remarkably express the photochromic effect, and the amount of resin adhered should be appropriately controlled during use. To In addition, in order to improve the light resistance of the compound (I), a resin material having an oxygen gas barrier property is preferable, and specifically, nylon 6, polypropylene, polyethylene terephthalate, polyvinyl alcohol, polyvinyl chloride, polyvinylidene chloride are preferable. , Polytrifluoroethylene, polyvinyl butyral, and the like. Polyvinyl alcohol is particularly useful as the resin binder used here. However, since polyvinyl alcohol is inferior in water resistance, the hydroxyl group of polyvinyl alcohol is a triazine-based crosslinking agent such as trimethylolmelamine, an isocyanate compound having three or more functional groups (for example, 3 mol of hexamethylene diisocyanate and 1 mol of trimethylolpropane). It is also possible to employ a resin formulation in which intermolecular crosslinking is performed with a triisocyanate crosslinking agent obtained by an addition reaction to improve water resistance.

The microcapsules of the compound (I) are dispersed in the resin solution and then applied to the fiber cloth. In this case, it may be applied in any form of an aqueous dispersion, an emulsion and an organic solvent solution. The application method can be carried out by an ordinary butting method, a pad steam method, a coating method, a laminating method, a spray method or the like. The amount of the compound (I) attached to the fiber cloth is equivalent to the disperse dye concentration of an ordinary polyester dyeing material. The amount required is 0.1 to 20% o. w. f
This is the range in which photoreversible discoloration appears most effectively. 0.1% o. w. If it is less than f, the photoreversible discoloration property is small and it is not practical, and conversely 20% o. w.
At around f, the photo-reversible discoloration reaches an almost equilibrium state, and even if more than that is attached, the effect hardly changes and it is rather economically disadvantageous.

(Example) Next, the present invention will be further described with reference to the examples. The measurement and evaluation of the performance of the cloth in the examples were performed by the following methods.

(1) Hue density color difference meter Macbeth Color Eye MS-2
The reflectance at a wavelength of 600 mμ was measured using 020, and the hue density K / S value was calculated by the Kubelka-Munk equation.

(2) Lightfastness JIS-L-0842 (carbon arc 20 hours irradiation) (3) Washing conditions After washing at 40 ° C for 10 minutes using a home washing machine, rinsing at room temperature for 3 minutes 3 times What was done and centrifugally dehydrated was washed once.

Example 1 First, microcapsules of the compound (I) used in this example were produced by the following method.

An emulsion was prepared by vigorously shaking a mixture of 100 cc of a 180 g / concentration aqueous sodium silicate solution and 200 cc of a benzene solution of polyoxyethylene sorbitan monostearate (concentration 20 g /). This emulsion has a concentration of 1.
After adding to 600 cc of 5 mol / sulfuric acid aqueous solution with stirring, the mixture is left for 1 hour, filtered, washed and dried to have a pore size of 10Å, a particle size of 3 to 5 µ, a composition of SiO ₂ 75%, H ₂ O.
28 g of 25% spherical porous hollow inorganic powder was obtained. next,
1,3,3-Trimethylspiro [indoline-2,3'-3H) -naphtho (2,1-) which is one of the compounds (I)
6) -1,4 Oxazine] (hereinafter, abbreviated as ASO) in an acetone solution (concentration: 150 g /) (20 cc) was injected into the porous hollow inorganic powder under a reduced pressure of 200 mmHg, and subsequently to 60 ° C. And dried. After drying, ASO adhering around the inorganic powder was washed off with distilled water and dried again at 100 ° C. to obtain ASO microcapsules. The composition of this microcapsule is SiO ₂
75% and ASO 3.5%.

Here, a plain woven fabric (taffeta; after scouring and dyeing with a cationic type fluorescent dye) having a warp density of 120 threads / inch and a weft density of 90 threads / inch using cationic dyeable polyester 75d / 36f for warp and weft Prepared, padded with Asahi Guard 710 (a product of Asahi Glass Co., Ltd.), which is a fusso-based water repellent Emulsion, with 5% water solubility (squeezing rate 35%), and heat-treated at 160 ° C for 1 minute. Using a calendering machine having a mirror surface roll, calendering was performed under the conditions of a temperature of 170 ° C., a pressure of 20 kg / cm ² , and a speed of 20 m / min to obtain a base fabric for a photoreversible discoloration fabric.

This woven fabric was coated with the resin solution shown in the following Formulation 1 using a knife over roll coater at a coating amount of 100 g / m ² and then dried at 80 ° C. for 5 minutes, followed by 1
Heat treatment was performed at 50 ° C. for 1 minute.

Prescription 1 Polyvinyl alcohol UMR-150L 100 parts (product of Unitika Kasei Co., Ltd.) ASO microcapsules 40 parts (ASO content 5%) Methyl ethyl ketone 80 parts Dimethylformamide 150 parts Crisbon BL-50 5 parts (isocyanate cross-linking agent, Dainippon Ink and Chemicals, Inc. Products) About the obtained cloth, its original cloth, after washing 5 times,
The performance of each of the carbon arcs after irradiation for 20 hours was measured, and the results are shown in Table 1.

As is clear from Table 1, the photo-reversible discolorable fabric of the present invention is 1
When it was left in the dark, the hue became lighter when it was exposed to sunlight or mercury lamp in January. Also, after 20 hours of carbon arc irradiation, the color was darkened by the irradiation of sunlight or mercury lamp in November, and it was lightened when left in the dark. The cloth after irradiation with this carbon arc for 20 hours was evaluated by gray scale judgment and was grade 4 of discoloration and fading, and had good light resistance.

(Effect of the invention) The photoreversible discolorable cloth of the present invention is prepared by encapsulating the spironaphthoxazine derivative represented by the general formula (I) in a porous spherical inorganic powder as a core substance to form microcapsules. According to the present invention having such a structure, a resin binder having an oxygen barrier property is applied to the fiber cloth, and according to the present invention, the light resistance and the washing resistance are excellent, and the excellent color developability and rapid repeated color change repetition are performed. It is possible to obtain a photoreversible discolorable cloth having properties. The photo-reversible color-changing fabric of the present invention can be widely used for various applications such as curtains and clothes.

Claims (1)

[Claims] 1. A fiber cloth provided with a spironaphthoxazine derivative represented by the following general formula (I) in the form of microcapsules enclosed as a core substance in a spherical porous hollow inorganic powder. A photo-reversible discolorable fabric that (In the formula, R is a lower alkyl group, X ₁ and X ₂ are hydrogen atoms,
Hydroxyl group, lower alkoxy group, or halogen atom, X ₃ ,
X ₄ is a hydrogen atom, a lower alkyl group, a lower alkoxy group,
Represents a halogen atom, nitro group, or cyan group. )