JP2005220201A - Lightfast temperature-sensitive discolorable composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a temperature-sensitive discolorable composition which is excellent in fastness to UV light and visible light. <P>SOLUTION: (1) This temperature-sensitive discolorable composition is prepared by compounding (d) a benzotriazole ultraviolet absorber and (e) a lightfastness improver comprising an α iron oxide particle having an average primary particle size of ≤0.20 μm to a temperature-sensitive discolorable material comprising (a) an electron-donative color-developing organic compound, (b) an electron-accepting compound and (c) a discoloration temperature controlling agent. (2) The temperature-sensitive discolorable composition is the one mentioned in (1) wherein the temperature-sensitive discolorable material and the benzotriazole ultraviolet absorber are encapsulated in microcapsules. (3) The temperature-sensitive discolorable composition is the one mentioned in (1) or (2) wherein the α iron oxide particle having the average primary particle size of ≤0.20 μm is a spherical particulate iron oxide pigment obtained through a hydrothermal method. (4) A temperature-sensitive discolorable paint wherein the temperature-sensitive discolorable composition mentioned in (1), (2) or (3) is compounded, an ink or articles coated with the ink or paint are also provided. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a light-resistant temperature-sensitive color-changing composition.

Conventionally, a temperature-sensitive color-changing composition comprising an electron-donating compound (leuco dye), an electron-accepting compound (developer), and a color-changing temperature adjusting agent has been used in many applications, taking advantage of its properties. (Patent Literature 1, Patent Literature 2, Patent Literature 3).
However, the temperature-sensitive color-changing composition has a problem that it degrades due to decomposition by ultraviolet rays or photooxidation by ozone generated by ultraviolet rays.
As a method for solving the above problem, for example, a coating film containing an ultraviolet absorber and an antioxidant is laminated on a synthetic resin layer containing a temperature-sensitive color-changing ink, and the light resistance of the ink composition is increased. There is an improved method (Patent Document 4).
However, photodegradation of the temperature-sensitive color-changing composition is caused not only by ultraviolet rays but also by visible rays, so that the above-mentioned Patent Document 4 is visible even if degradation by ultraviolet rays can be prevented. It has the disadvantage that it cannot cope with deterioration due to light rays.
Therefore, as a method for coping with deterioration due to visible light, a method using a light resistance improver made of a compound having a specific structure has been developed (Patent Document 5).

JP 59-120492 A Japanese Examined Patent Publication No. 62-28990 JP 7-40660 A Japanese Patent Publication No. 4-18543 JP 2003-313453 A

  The above-mentioned method is epoch-making in that it has light resistance not only to ultraviolet rays but also to visible rays. Since it is decomposed or deteriorated by light such as a fluorescent lamp, it is difficult to maintain the original reversible temperature-sensitive color-changing function of the temperature-sensitive color-changing composition outdoors or in a bright room for a long time. As for the use of the light-sensitive composition, there are many applications for indoor use, and further development of a thermochromic composition having excellent light fastness is awaited even outdoors or in bright rooms.

  An object of the present invention is to provide a thermochromic composition having excellent light fastness against ultraviolet rays and visible light.

  The inventors of the present invention have made extensive studies in order to solve the above problems, and as a result, when a light resistance improver composed of a specific ultraviolet absorber and a visible light absorbing component is added to the thermochromic material, excellent light fastness is obtained. As a result of further research, it was completed that the present invention was completed.

The present invention comprises the following inventions.
1. (I) a temperature-sensitive color-changing material comprising an electron-donating color-forming organic compound, (b) an electron-accepting compound, and (c) a color-changing temperature adjusting agent; (d) a benzotriazole-based ultraviolet absorber; A temperature-sensitive discoloration composition comprising a light fastness improver composed of α-iron oxide particles having an average primary particle size of 0.20 μm or less.
2. 2. The temperature-sensitive color-changing composition according to 1 above, wherein the temperature-sensitive color-changing material and the benzotriazole ultraviolet absorber are encapsulated.
3. 3. The temperature-sensitive color-changing composition according to 1 or 2 above, wherein the α iron oxide particles having an average primary particle size of 0.20 μm or less are spherical fine particle iron oxide pigments obtained by a hydrothermal method.
4). A temperature-sensitive color-changing paint, ink, or a coated product thereof, characterized in that the temperature-sensitive color-changing composition described in the above 1, 2, or 3 is blended.
5). 5. The temperature-sensitive color-changing coated product according to 4 above, wherein the coated product is a printed product, a printed product, a coated product, a painted product, or a written product.
6). A temperature-sensitive color-changing molded article obtained by molding a molding resin composition containing the temperature-sensitive color-changing composition described in the above 1, 2, or 3.
7). Coating composed of a temperature-sensitive color-changing material comprising (a) an electron-donating color-forming organic compound, (b) an electron-accepting compound, and (c) a color-change temperature adjusting agent, coated with a light-resistant protective film In the article or molded article, the light-resistant protective film contains at least one of (e) a light-resistance improving agent composed of α-iron oxide particles having an average primary particle diameter of 0.20 μm or less and (d) a benzotriazole-based ultraviolet absorber. A temperature-sensitive color-changing coated or molded product, characterized in that both agents are present in the light-resistant protective film and the entire substrate of the coated or molded product.
8). 8. The temperature-sensitive discoloration coated or molded product according to 7 above, wherein the light-resistant protective film has a thickness of 10 μm or more.
9. 5. The sensation as described in 4 above, wherein the α iron oxide particles blended in the temperature-sensitive color-changing paint, temperature-sensitive color-changing molded product, or light-resistant protective film are 0.1 to 30 parts by weight with respect to 100 parts by weight of the synthetic resin. 9. A thermochromic paint, or a thermochromic molded article according to the above 6, 7 or 8.

The light-resistant thermochromic composition of the present invention is a thermochromic material comprising (a) an electron-donating color-forming organic compound, (mouth) an electron-accepting compound, and (c) a color-changing temperature adjusting agent. And (d) a benzotriazole-based ultraviolet absorber and (e) a light fastness improver composed of α-iron oxide particles having an average primary particle size of 0.20 μm or less.
The temperature-sensitive color-changing composition of the present invention is an epoch-making one having light resistance not only to ultraviolet rays but also to visible light.

The present invention has been made based on the following findings.
(1) When ultraviolet rays are irradiated, ozone and oxygen radicals are generated. However, the normal temperature-sensitive color-changing composition is deteriorated by ozone, oxygen radicals, etc., so that the composition is composed of an ultraviolet absorber or an oxidant. It is said that it needs to be protected by an inhibitor or the like.
(2) However, although the ultraviolet absorber absorbs UV-A, UV-B, and UV-C ultraviolet rays of 400 nm or less, it does not exhibit an effect on short-wavelength visible light.
(3) On the other hand, the temperature-sensitive color-changing composition is decomposed or deteriorated not only by ultraviolet rays of 400 nm or less, but also by visible light emitted from sunlight or fluorescent lamps, and particularly by visible light having a short wavelength of 400 to 600 nm. I learned that the impact was significant.
(4) In order to solve the above problem, the applicant has previously developed a thermochromic composition having light resistance not only to ultraviolet rays but also to visible rays (Patent Document 5).
(5) A new temperature-sensitive color-changing composition having light fastness that is not inferior to that of the above-mentioned invention was obtained, and when many studies were repeated, the average primary particle diameter was finally 0.20 μm or less. It has been found that alpha iron oxide particles absorb short wavelength rays of 600 nm or less.
(6) Therefore, when a light fastness improver composed of the α iron oxide particles and the benzotriazole-based ultraviolet absorber is blended in the temperature-sensitive color-changing composition, the synergistic effect can be applied to both ultraviolet rays and visible rays. However, a practical temperature-sensitive color-changing composition with improved light resistance was obtained.

In any case, the present invention provides a light resistance improver for the thermochromic composition, a benzotriazole-based ultraviolet absorber and an α-average particle size of 0.20 μm or less that absorbs short-wavelength visible light of 600 nm or less. The discovery of iron oxide particles has led to the development of such a novel light fastness improver, which makes it possible to produce a thermochromic composition having excellent light fastness not only for ultraviolet rays but also for visible light rays. It became possible to provide.
Therefore, since ordinary temperature-sensitive color-changing compositions are inferior in light fastness, many of them are for indoor use, but the temperature-sensitive color-changing composition of the present invention has unprecedented light fastness. As a result, its use has become more widespread, such as outdoor or bright indoor use.

Hereinafter, the present invention will be described in more detail.
The light-resistant thermochromic composition of the present invention is a thermochromic material comprising (a) an electron-donating color-forming organic compound, (b) an electron-accepting compound, and (c) a color-changing temperature adjusting agent. And (d) a light resistance improver comprising (iii) a benzotriazole-based ultraviolet absorber and (e) an α-iron oxide particle having an average primary particle size of 0.20 μm or less.
Then, the component of the said thermosensitive color-change composition of this invention, its use, etc. are demonstrated.

(1) Temperature-sensitive color-changing composition The temperature-sensitive color-changing composition is reversibly discolored in response to temperature changes, and is quasi-reversible with a history of color-changing behavior when temperature rises or falls. The temperature-sensitive discoloration is brought about by (a) an electron-donating color-forming organic compound and (b) an electron-accepting compound, and the discoloration temperature is (c) a discoloration temperature adjusting agent. Can be adjusted.

(I) Electron-donating color-forming organic compound The electron-donating color-forming organic compound is a component that develops a color reaction (discoloration) with the following electron-accepting compound (developer), As the compound, known compounds can be used, but a leuco dye is optimal.
As this dye, a colorless or light leuco dye can be used. Examples of the dye include those commonly known as pressure-sensitive copying paper dyes and heat-sensitive recording paper dyes, and other thermochromic compositions. Any conventionally known leuco dye constituting the product can be used.
For example, triphenylmethane phthalide, fluoran, phenothiazine, indolylphthalide, leucooramine, spiropyran, rhodamine lactam, triphenylmethane, triazene, spirophthalanthanthene, naphtholactam, Any conventionally known one such as azomethine can be used.
Specific examples of such leuco dyes include 3,6-dimethoxyfluorane, 3,6-dibutoxyfluorane, 3-diethylamino-6,8-dimethylfluorane, 3-chloro-6-phenylaminofluorane. 3-diethylamino-6-methyl-7-chlorofluorane, 3-diethylamino-7,8-benzofluorane, 3,3-bis (p-dimethylaminophenyl) phthalide, 3-diethylamino-7-phenylaminofluor Oran, 3,3-bis (p-diethylaminophenyl) -6-dimethylaminophthalide, 3- (4-diethylaminophenyl) -3- (1-ethyl-2-methylindol-3-yl) phthalide, 3- (4-diethylamino-2-methyl) phenyl-3- (1,2-dimethylindol-3-yl) phthalide, 2,- 2-chloroanilino) -6 - dibutylaminoethyl spiro (phthalide -3,9, - xanthene), but can be given, but not limited to course this like.
In the present invention, these leuco dyes can be used singly or in combination of two or more, whereby the color at the time of color development is yellow, orange, red, peach, magenta, purple, blue, green, brown, Any color such as black can be used.

(B) Electron-accepting compound The electron-accepting compound is a color developer and develops a color reaction with the electron donating color-forming organic compound (leuco dye) described in (a) above (color change). Known components can be used.
Examples of the electron-accepting compound (developer) include triazoles, phenols, bisphenols, aromatic carboxylic acids, aliphatic carboxylic acids, thioureas, phosphoric acids, or esters thereof, ethers In addition, those known for pressure-sensitive and heat-sensitive copying paper such as metal salts can be used.
In the present developer, the developer can be used alone or in combination of two or more. The amount of use is not particularly limited, but can usually be selected in the range of about 0.1 to 1000 parts by weight per 1 part by weight of the leuco dye.

(C) Color change temperature adjusting agent The color change temperature adjusting agent is the temperature of the color reaction of the above (a) electron donating color developing organic compound (leuco dye) and (b) electron accepting compound (developer). It is a component for controlling. By using this color change temperature adjusting agent, the color change temperature can be freely controlled.
As the present color changing temperature adjusting agent, any conventionally known organic medium that is used as the color changing temperature adjusting agent in this type of temperature sensitive color changing composition can be used. For example, a wide range can be selected from alcohols, esters, ethers, ketones, amides, azomethines, fatty acids, hydrocarbons, and the like.

(2) Light resistance improver The light resistance improver comprises a benzotriazole-based ultraviolet absorber and α iron oxide particles having an average primary particle diameter of 0.20 μm or less, and forms the basis of the present invention.

[(D) Benzotriazole UV absorber]
The present benzotriazole-based ultraviolet absorber is made of a benzotriazole compound and has a function of absorbing ultraviolet rays of 400 nm or less.
Therefore, when used in combination with α-iron oxide particles having a visible light absorption ability of 600 nm or less, excellent light resistance can be imparted to the thermochromic material.
As this benzotriazole ultraviolet absorber, 2- (5-t-butyl-2-hydroxyphenyl) -benzotriazole (trade name: Tinuvin-PS, manufactured by Ciba Geigy Co., Ltd.), 2- (5-methyl-2) -Hydroxyphenyl) -benzotriazole, 2- (2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl) 2H-benzotriazole, 2- (3,5-di-tert-butyl-2- Hydroxyphenyl) -benzotriazole, 2- (3-t-butyl-5-methyl-2-hydroxyphenyl) -5-chlorobenzotriazole, 2- (3,5-di-t-amyl-2-hydroxyphenyl) -Benzotriazole (trade name: Tinuvin 328, manufactured by Ciba-Geigy Corporation), methyl-3- (3-t-butyl-5- (2H-benzotriazo) Ol-2-yl) -4-hydroxyphenyl) propionate-polyethylene glycol molecular weight 300 (trade name: Tinuvin 1130, manufactured by Ciba Geigy Co., Ltd.), 2- (3-dodecyl-5-methyl-2-hydroxyphenyl) benzo Triazole, methyl-3- (3- (2H-benzotriazol-2-yl) -5-tert-butyl-4hydroxyphenyl) propionate-polyethylene glycol molecular weight 300, 2- (3-tert-butyl-5-propyl octylate 2-hydroxyphenyl) -5-chlorobenzotriazole, 2- (3-t-butyl-5-octyloxycarbonylethyl-2-hydroxyphenyl) -benzotriazole (trade name: Tinuvin 384, manufactured by Ciba-Geigy Corporation) , 2- (2-bidoxy-5-t-octylfe ) -Benzotriazole, 2- (2-hydroxy-3- (3,4,5,6, -tetrahydrophthalimidomethyl) -5-methylphenyl) -benzotriazole, and the like. It is not limited to these as long as it has an ultraviolet absorption effect.
The amount of the ultraviolet absorber used may be in the range of 0.1 to 30.0% by weight with respect to the thermochromic composition, and preferably in the range of 1.0 to 25.0% by weight. good. This is because when the amount is less than 0.1%, the effect of improving light resistance is small, and when the amount exceeds 30.0%, the sensitivity of discoloration is impaired.

[(E) α iron oxide particles]
The present α iron oxide particles are yellow to orange particles having an α-type lattice structure having the structure of Fe ₂ O ₃ , and transparency is obtained by controlling the average primary particle diameter to 0.20 μm or less. Even if it is used as a light fastness improver, it absorbs visible light of 600 nm or less without disturbing the original function of the temperature-sensitive color-changing material, that is, the color reversibly changes with temperature. It can improve the light resistance of the material and is the most important component of the present invention.
As the α iron oxide particles, those having an average primary particle diameter of 0.20 μm or less, preferably 0.001 to 0.20 μm are used.
When the average primary particle size is 0.20 μm or more, as the particle size increases, the pigment becomes opaque and strongly concealed with a red color. Generally, iron oxide pigments with a particle size of 0.5 μm or more are red inorganic pigments. Although these iron oxide pigments have been known for a long time as a light resistance improver for temperature-sensitive color-changing compositions, the color of the temperature-sensitive color-changing composition is reduced due to their strong coloring power and opacity. Since it is concealed, it is not suitable as a light resistance improver.
In addition, since the γ-type iron oxide particles are used as a magnetic substance, and the color is generally black to dark brown, when this is also used as a light resistance improver, the dark color is reduced. The color change inhibits the original color change of the thermochromic material and is not suitable as the light fastness improver of the present invention.
Therefore, in the present invention, only the above-mentioned α iron oxide particles can be used, and the light resistance of the temperature-sensitive color-changing composition can be remarkably improved by using in combination with the above-mentioned (d) benzotriazole ultraviolet absorber. Can do.
And the denser the arrangement of α iron oxide particles in the coating film, the better the visible light absorption effect of 600 nm or less, and the particle shape of α iron oxide particles is more than the acicular α iron oxide particles produced by the firing method. It is preferable to use a spherical product produced by a hydrothermal method.

(3) Microcapsules The temperature-sensitive color-changing material is preferably microencapsulated.
This is because the color-changing component of the temperature-sensitive color-changing material is protected by encapsulating it in an independent micro-enclosed system, and if not blended in the paint, ink, or synthetic resin, the organic solvent or surfactant in the paint This is because the original function of the temperature-sensitive color-changing material, that is, the function of causing the color change reversibly due to the temperature change is lost due to the influence of the synthetic resin, the additive and the like.
In microencapsulation, if necessary, a benzotriazole ultraviolet absorber which is a light resistance improver can be microencapsulated together.
The average primary particle size of microencapsulation is 0.5 to 20 μm, preferably 0.5 to 15 μm. When the particle diameter is smaller than 0.5 μm, the color density is low and the effect of protecting the inclusions is poor. On the other hand, when the particle diameter is larger than 20 μm, the coated surface is poor in smoothness, and the microcapsules are destroyed by physical stress during processing, thereby impairing the original function of the thermochromic material.
Therefore, the thermochromic material composed of the above components must be encapsulated in a microsystem by applying various microencapsulation techniques. As a microencapsulation method, a conventional method such as coacervation can be used. Method, in situ polymerization method, interfacial polymerization method, submerged curing coating method, air suspension coating method, spray drying method, and the like. Different methods can be used together.
Examples of microencapsulated wall membrane materials include polyamines and carbonyl compounds for forming polyurea wall membranes, polybasic acid chlorides and polyamines for forming polyamide wall membranes, and polyurethane wall membranes. Polyhydric isocyanate and polyol compound for forming epoxy resin wall film, epoxy resin and polyamine, melamine formalin prepolymer, methylol melamine prepolymer, methylated melamine prepolymer for forming melamine resin wall film, Urea formalin prepolymer for forming urea resin wall film, phenol resin prepolymer for forming phenol resin wall film, vinyl acetate, styrene, (meth) acrylic acid ester for forming vinyl resin wall film, Various monomers such as acrylonitrile and vinyl chloride, Examples thereof include latin, gum arabic, polyvinyl alcohol, ethyl cellulose, carboxymethyl cellulose, and styrene / maleic acid resin. However, the present invention is not limited to these, and two or more types can be used in combination. .
Then, after forming the primary microcapsule wall film, the physical strength of the microcapsules may be further improved by coating and curing the wall film resin again to form a double wall film.

(4) Use The light-resistant thermochromic composition of the present invention can be used as a thermochromic paint or ink, or a coated or molded product thereof.

1) Paint and ink The temperature-sensitive color-changing composition of the present invention is mixed with a water-soluble fixing agent or oil-soluble fixing agent to obtain a temperature-sensitive color-changing aqueous coating material or ink, or oil-based coating material or ink.
The blending amount of the α iron oxide particles is in the range of 0.1 to 30 parts by weight, preferably 0.5 to 20 parts by weight with respect to 100 parts by weight of the synthetic resin in the paint or ink.
The addition amount of the benzotriazole-based ultraviolet absorber is in the range of 0.05 to 20 parts by weight, preferably 0.05 to 10 parts by weight with respect to 100 parts by weight of the synthetic resin in the paint or ink.

(Water-based paint, ink)
Water-soluble adhesives include polyester resin, polyurethane resin, (meth) acrylic ester resin, polyvinyl chloride resin, polyvinyl acetate resin, ethylene / vinyl acetate resin, polycarbonate resin, epoxy resin, acrylic silicone resin, acrylic / urethane Resins, alkyd resins, emulsions of ethylene / polyvinyl alcohol resins, UV-cured or electron-beam cured emulsions of these monomers and oligomers and sensitizers, or carboxymethylcellulose, hydroxyethylcellulose, methylcellulose, polyvinyl alcohol, poly Although a water-soluble fixing agent such as (meth) acrylic acid ester copolymer can be used, the present invention is not limited to these, and two or more kinds can be used in combination.
For water-based paints or inks, surfactants, plasticizers, curing agents, catalysts, thickeners, photosensitizers, general organic pigments or inorganic pigments as permanent colors, extender pigments, phosphorescents as necessary. Pigments, photochromic dyes, pearl pigments, metal powders, metal soaps, antioxidants and the like can be added.

(Oil paint, ink)
The thermochromic composition of the present invention is blended with an oil-soluble fixing agent to obtain a thermochromic oil-based paint or ink, but when the thermochromic microcapsule is produced in water, it is filtered. And it dries and uses for oil-based paint or ink. The drying method is not particularly limited and can be obtained by a conventional method such as spray drying or freeze drying.
Oil-soluble adhesives include polyester resin, polyurethane resin, (meth) acrylic ester resin, polyvinyl chloride resin, polyvinyl acetate resin, ethylene / vinyl acetate resin, polycarbonate resin, epoxy resin, acrylic silicone resin, acrylic / urethane Resins, alkyd resins, ethylene / polyvinyl alcohol resins, oil-free polyester resins, melamine resins, nylon resins, etc. dissolved in organic solvents, or those dissolved by heating, and their monomers, oligomers and sensitizers However, it is not limited to these, and two or more types can be used in combination.
For oil-based paints or inks, surfactants, plasticizers, curing agents, catalysts, thickeners, photosensitizers, general organic or inorganic pigments as an invariant color, extender pigments, phosphorescents as necessary. Pigments, photochromic dyes, pearl pigments, metal powders, metal soaps, antioxidants and the like can be added.

2) Coated product The coated product of the present invention includes a printed product, a coated product, a painted product, a written product, etc., and the coated product is printed, coated and painted with the thermosensitive color-changing paint or ink. It is obtained by applying to an object using means such as writing.

(Printed matter)
The above inks can be used for fiber, paper, plastic film, plastic sheet, plastic container, metal by gravure printing, rotary screen printing, silk screen printing, offset printing, dry offset printing, tampo printing, melt printing, letterpress printing, etc. By printing on glass, non-woven fabric, etc., it is possible to obtain a light-fast and temperature-sensitive discoloration printed matter that is excellent over a long period of time.

(Coating)
The above-mentioned paint is coated on cloth, paper, plastic film, metal, etc. with a knife coater, comma coater, padding, wire coater, reverse coater, roll coater, melt coat, etc., and has excellent light fastness over a long period of time. A temperature-sensitive discoloration coating can be obtained.

(Painted material)
The above paints have excellent light-resistant temperature-sensitive discoloration over a long period of time by hand spraying, electrostatic coating, or brush coating on cloth, paper, plastic films / sheets / containers, metal, glass, nails, etc. A characteristic paint is obtained.

(Writing materials)
The above inks can be filled into various marker pen containers, crayons, pastels can be manufactured, and using these writing instruments, writing on cloth, paper, plastics, metals, glass, etc. for a long time, An excellent light-resistant thermochromic writing is obtained.

3) Molded product A thermochromic molded product can be produced by molding a molding resin composition containing the thermosensitive color-changing composition.

(Resin composition for molding)
The thermochromic molding resin composition can be obtained by blending the thermochromic composition of the present invention with a thermoplastic synthetic resin.
The resin composition for molding may be a master batch or may be in the form of color pellets that are put into a molding machine and molded.
The blending amount of the alpha iron oxide particles in the resin composition for molding is 0.1 to 30 parts by weight, preferably 0.5 to 20 parts by weight with respect to 100 parts by weight of the resin.
Further, the addition amount of the benzotriazole-based ultraviolet absorber is 0.05 to 20 parts by weight, preferably 0.05 to 10 parts by weight with respect to 100 parts by weight of the resin.
Molding resins include polyethylene resin, polypropylene resin, ABS resin, AS resin, K resin resin, styrene resin, silicone resin, polyester resin, polyurethane resin, (meth) acrylate resin, polyvinyl chloride resin, polyvinyl acetate Resin, ethylene / vinyl acetate resin, polycarbonate resin, ethylene / polyvinyl alcohol resin, 6 nylon resin, 6,6 nylon resin, 12 nylon resin, copolymer nylon resin, polyacetal resin, etc. can be used. It is not limited and it can also be used in combination of 2 or more types.
The molding resin composition includes a dispersant, a surfactant, a plasticizer, a wax, a curing agent, a catalyst, a thickener, a general organic pigment or an inorganic pigment as an invariant color, and a constitution as necessary. Pigments, luminous pigments, photochromic dyes, pearl pigments, metal powders, metal soaps, antioxidants, and the like can be added.

(Molding method)
The molding resin composition is diluted with a general thermoplastic synthetic resin, and the temperature-sensitive color-changing color pellets are not diluted, but are usually molded, for example, an injection molding method, an extrusion molding method, By a blow molding method, it can be molded into molded products of various desired shapes.
Further, after extrusion molding, the film is stretched to obtain a doll's hair, embroidery thread, sewing thread and the like as a thread. The obtained molded product becomes a thermochromic molded product having excellent light fastness over a long period of time.

4) Light-resistant protective film α-iron oxide particles having an average primary particle diameter of 0.20 μm or less or α-iron oxide particles and a benzotriazole-based ultraviolet absorber By forming a light-resistant protective film made of the above, it is possible to obtain a coated or molded product with further improved light resistance.
When a light-resistant protective film is provided on the surface of the coated product or molded product, the α iron oxide particles or the benzotriazole-based ultraviolet absorber that is not present in the protective film is applied to the substrate of the coated product or molded product. Both agents must be present in the light-resistant protective film and the entire substrate of the coated product or molded product.
The light-resistant protective film may be a water-soluble or oil-soluble paint (ink) or heat-dissolved, and synthetic resins used include polyester resins, polyurethane resins, and (meth) acrylic ester resins. , Polyvinyl chloride resin, polyvinyl acetate resin, ethylene / vinyl acetate resin, polycarbonate resin, epoxy resin, acrylic silicone resin, acrylic / urethane resin, alkyd resin, ethylene / polyvinyl alcohol resin, oil-free polyester resin, melamine resin, nylon Emulsions such as resins, or those dissolved in an organic solvent, or those dissolved by heating, or those obtained by ultraviolet curing or electron beam curing of these monomers and oligomers and sensitizers can be used. It is not limited to these. It can also be used in conjunction seen.
The light-resistant protective film may include a surfactant, a plasticizer, a curing agent, a catalyst, a thickener, a photosensitizer, a general organic pigment or inorganic pigment as an invariant color, an extender, if necessary. Phosphorescent pigments, photochromic dyes, pearl pigments, metal powders, metal soaps, waxes, dispersants, antioxidants, and the like can be added.

(Film formation method)
The above light-resistant protective film can be applied to the above-mentioned thermochromic coated or molded product by hand spray coating, electrostatic coating, brush coating, screen printing, gravure printing, coating, extrusion film formation, calendar film formation or The thickness is preferably 10 μm or more by a method such as laminating, and preferably 20 μm or more. When the thickness of the light-resistant protective film is 10 μm or less, a sufficient light-resistant protective effect cannot be obtained.
The obtained temperature-sensitive color-changing coated product and molded product become a temperature-sensitive color-changing product excellent in light fastness for an extremely long period of time.

(1) Since the temperature-sensitive color-changing composition of the present invention contains a light-resistant component, a benzotriazole-based ultraviolet absorber, and fine α-iron oxide particles having an average primary particle size of 0.20 μm or less, and thus transparent, An all-weather temperature-sensitive color-changing product that is light-resistant not only to ultraviolet rays but also to visible light can be obtained, but the light resistance is extremely excellent in that it can be sustained for a long period of time.
(2) Therefore, the thermochromic composition of the present invention was able to produce a thermochromic product that can be used outdoors, which has been difficult in the past, and its application has greatly expanded.
(3) For example, the temperature-sensitive color-changing composition, which has been difficult in the past due to the problem of light fastness, is also used in automotive paints, bicycle paints, outdoor bulletin boards, outdoor paints, outdoor toys, game machines, etc. It became possible to do.

  Hereinafter, although an example etc. are given and the present invention is explained still in detail, the present invention is not limited to these. In the following examples and the like, “parts” and “%” mean “parts by weight” and “% by weight” unless otherwise specified.

(Example 1)
In a 200 cc beaker, 1.5 parts of 3-dibutylamino-7,8-benzofluorane, 3 parts of bisphenol A, 10 parts of lauryl palmitate, 10 parts of cetyl alcohol, and tinuvin 326 ( 5 parts of Ciba Geigy Co., Ltd.) was added and dissolved by heating at 100 ° C. to prepare a temperature-sensitive color-changing solution.
In addition, 400 parts of an aqueous solution of methyl vinyl ether / maleic anhydride copolymer resin (GANTREZ AN-179: manufactured by GAF CHEMICALS) neutralized and dissolved in NaOH as a protective colloid agent is placed in a 1 liter beaker, and 95-100 Heated to ° C.
While stirring the solution in the obtained 1-liter container, the above-mentioned temperature-sensitive color-changing solution was gradually added and emulsified, the stirring speed was adjusted, and the average particle size of the oil droplets was adjusted to 2 μm.
After the adjustment, while continuing stirring, 200 parts of a 50% methylolmelamine aqueous solution was gradually added as a capsule film agent, followed by heating and stirring for 4 hours to obtain thermochromic microcapsules.
To 20 parts of the resulting thermochromic microcapsule solution, as a water-soluble fixing agent, 70 parts of Matsumine Binder S (clear binder containing an acrylate emulsion: manufactured by Matsui Dye Chemical Co., Ltd.), 25% 10 parts of spherical α iron oxide particle aqueous dispersion (average primary particle size 0.06 μm) was mixed to obtain a temperature-sensitive color-changing ink.
Subsequently, the obtained temperature-sensitive color-changing ink was printed on a cotton knit using an 80-mesh screen plate and dried to obtain a target temperature-sensitive color-changing printed cloth excellent in light fastness. .
The obtained printed cloth exhibited a red color at a temperature lower than 35 ° C. and changed to a yellow color at 35 ° C. or higher.
Further, as a result of testing the light fastness of the printed cloth with a fade meter, sun exposure, and fluorescent lamp, the printed cloth had excellent light fastness as shown in Table 1 below.

(Example 2)
5% oxalic acid was added to the thermochromic microcapsule solution obtained in Example 1 to adjust the pH to 2.0, and the water dispersibility of methyl vinyl ether / maleic anhydride copolymer resin as a protective colloid agent was adjusted. The function was lowered to make an unstable dispersion system. Subsequently, it filtered with the filter press and obtained the thermochromic microcapsule of 40% of moisture content.
The obtained temperature-sensitive color-changing microcapsules 64 parts were again put into a 1-liter beaker, 400 parts of water was added, and then heated to 95 to 100 ° C. While stirring the obtained solution, 20 parts of 50% methylolmelamine aqueous solution was gradually added dropwise as a capsule film agent, reacted for 4 hours, and filtered with a filter press to give a temperature-sensitive color change with a water content of 40%. A double-encapsulated temperature-sensitive color-changing microcapsule enclosing a sexual component was obtained.
Subsequently, the obtained microcapsules having a water content of 40% were diluted 10-fold with water and dried using a spray dryer to form the microcapsules.
10 parts of the resulting powder-like thermochromic microcapsules and as oil-soluble fixing agent, clear Q-086A (clear paint of acrylic ester / urethane copolymer resin dissolved in organic solvent: made by Isamu Paint Co., Ltd.) 80 parts, 10 parts of a 25% spherical α iron oxide particle organic solvent dispersion (average primary particle size 0.03 μm), and 5 parts of Fixer Q-086B (isocyanate-based curing agent: Isam Paint Co., Ltd.) as a curing agent A temperature-sensitive color-changing paint was obtained by blending.
The obtained paint is applied to a 0.5 mm thick iron plate previously coated with a white paint by hand spraying at a thickness of 100 g / m ² and dried at 60 ° C. for 30 minutes to achieve the desired light resistance. An excellent temperature-sensitive discoloration paint was obtained.
The obtained coated product was red when the temperature was lower than 35 ° C. and changed to yellow when the temperature was 35 ° C. or higher.
Moreover, as a result of testing the light fastness of this coated product using a fade meter, sun exposure, and a fluorescent lamp, it was found to have excellent light fastness as shown in Table 1 below.

(Example 3)
20 parts of powder-like thermochromic microcapsules obtained in Example 2, 55 parts of polyethylene resin, 1 part of magnesium stearate, 14 parts of low molecular weight polyethylene wax, spherical α iron oxide particles (average primary particle size 0.03 μm) ) 10 parts were dry blended and processed with an extrusion molding machine to obtain a temperature sensitive discoloration masterbatch.
Next, 10 parts of the obtained thermochromic masterbatch and 90 parts of polyethylene resin were dry blended, and a 10 cm × 10 cm plate having a thickness of 2 mm was molded using an injection molding machine.
The obtained thermochromic plate was red at less than 35 ° C. and reversibly changed to yellow at 35 ° C. or higher.
Further, as a result of testing the light fastness of the plate-like material with a fade meter, exposure to sunlight, and a fluorescent lamp, it showed excellent light fastness as shown in Table 1 below.

Example 4
10 parts of powdery thermochromic microcapsules obtained in Example 2; 80 parts of epoxy clear H (epoxy resin: manufactured by Matsui Pigment Chemical Co., Ltd.) as an oil-soluble fixing agent; 20% spherical alpha iron oxide Mix 10 parts of particle organic solvent dispersion (average primary particle size 0.03 μm), 50 parts of epoxy fixer H (amine curing agent: manufactured by Matsui Dye Chemical Co., Ltd.) and 50 parts of xylene as a curing agent. A temperature-sensitive color-changing paint was obtained.
The obtained temperature-sensitive color-changing paint is applied by hand spraying on a glass plate previously coated with a white paint so as to have a thickness of 150 g / m ^2, and heat-cured at 140 ° C. for 20 minutes to obtain the desired light resistance. An excellent temperature-sensitive discoloration paint was obtained.
The obtained temperature-sensitive color-changing glass exhibited a red color at a temperature lower than 35 ° C., and reversibly changed to a yellow color at 35 ° C. or higher.
Further, as a result of testing the light fastness of this glass with a fade meter, exposure to sunlight, and a fluorescent lamp, the glass showed excellent light fastness as shown in Table 1 below.

(Example 5)
10 parts of powdery thermochromic microcapsules obtained in Example 2, 80 parts of clear R-073-PEU-1 (ultraviolet curable clear paint: made by Isamu Paint Co., Ltd.) as an oil-soluble fixing agent, 10 parts of a 20% acicular iron oxide particle acrylic monomer dispersion (average primary particle size 0.001 μm) was mixed to obtain a temperature-sensitive color-changing paint.
The obtained temperature-sensitive color-changing paint is applied to an ABS plastic plate with a hand spray so that the thickness is 150 g / m ^2, and cured by irradiating with a 1 kW metal halide lamp for 10 seconds with ultraviolet light to achieve the desired light resistance. An excellent temperature-sensitive discoloration paint was obtained.
The obtained temperature-sensitive color-changing plastic plate was red at a temperature lower than 35 ° C. and reversibly changed to yellow at a temperature higher than 35 ° C.
Further, as a result of testing the light fastness of this plastic plate with a fade meter, exposure to sunlight, and a fluorescent lamp, it showed excellent light fastness as shown in Table 1 below.

(Example 6)
On the thermochromic printed fabric obtained in Example 1, Matsumin Rubber Binder MSB-N (Clear Binder Containing Acrylic Ester Emulsion: Made by Matsui Dye Chemical Co., Ltd.) as a Light Resistant Protective Film 90 parts, 10 parts of a 25% spherical α iron oxide particle aqueous dispersion (average primary particle size 0.03 μm), 2 parts of Fixer F (ethyleneimine-based curing agent: manufactured by Matsui Color Chemical Co., Ltd.) as a curing agent The light-resistant protective paint mixed with the above is printed on a 50-mesh screen plate, dried to a dry thickness of 15 μm, a protective film is laminated, and the desired temperature-sensitive discoloration is excellent. A printed fabric was obtained.
The obtained temperature-sensitive color-changing printed cloth exhibited red at a temperature lower than 35 ° C. and reversibly changed to yellow at a temperature higher than 35 ° C.
In addition, as a result of testing the light fastness of this printed cloth with a fade meter, sun exposure, and fluorescent lamp, as shown in Table 1 below, it shows light fastness superior to that of the printed cloth obtained in Example 1. Met.

(Example 7)
Q085-1A (including spherical α-iron oxide particles having an average primary particle size of 0.03 μm and an acrylate ester / urethane copolymer resin as a light-resistant protective film on the thermochromic coating obtained in Example 2 was used. Solvent-type protective paint: 100 parts of Isamu Paint Co., Ltd., 150 g of light-resistant protective paint mixed with 10 parts of Q-085-1B (isocyanate-based hardener: Isamu Paint Co., Ltd.) as a curing agent / M ² (dry thickness 45 μm) was applied by hand spraying and dried and cured at 60 ° C. for 30 minutes to obtain a desired thermochromic coating with excellent light resistance.
The obtained temperature-sensitive color-changing coating exhibited a red color below 35 ° C. and reversibly changed to yellow above 35 ° C.
Moreover, as a result of testing the light fastness of this coated product with a fade meter, sun exposure, and fluorescent lamp, the light fastness superior to that of Example 2 was shown as shown in Table 1 below.

(Example 8)
On the thermochromic molded product obtained in Example 3, as a light-resistant protective film, Q085-1A (including spherical α iron oxide particles having an average primary particle size of 0.03 μm and an acrylate ester / urethane copolymer resin) Solvent type protective paint: 100 parts by Isamu Paint Co., Ltd., and a light-resistant protective paint mixed with 10 parts Q-085-1B (isocyanate-based hardener: Isamu Paint Co., Ltd.) as a curing agent, It was applied by hand spraying at a thickness of 200 g / m ² (dry thickness 60 μm), dried and cured at 60 ° C. for 30 minutes, and a target thermosensitive color-changing molded product with extremely excellent light resistance was obtained.
The obtained thermochromic molded product exhibited a red color at a temperature lower than 35 ° C. and reversibly changed to a yellow color at 35 ° C. or higher.
Further, as a result of testing the light fastness of this molded product with a fade meter, exposure to sunlight, and a fluorescent lamp, the light fastness superior to that of Example 3 was shown as shown in Table 1 below.

Example 9
On the thermochromic coating obtained in Example 4, as a light-resistant protective film, 100 parts of epoxy clear H (epoxy resin clear: manufactured by Matsui Dye Chemical Co., Ltd.), 25% spherical α iron oxide particles As an organic solvent dispersion (average primary particle size 0.03 μm) 20 parts, as a curing agent, epoxy fixer H (amine curing agent: manufactured by Matsui Dye Chemical Co., Ltd.) 50 parts, as a benzotriazole ultraviolet absorber, A light-resistant protective paint mixed with 1 part of Tinuvin 326 (manufactured by Ciba Geigy Co., Ltd.) and 39 parts of xylene was applied by hand spraying at a thickness of 200 g / m ² (dry thickness 60 μm) and cured at 140 ° C. for 30 minutes. As a result, a temperature-sensitive color-changing coated product having extremely excellent light resistance was obtained.
The obtained temperature-sensitive color-changing coating exhibited a red color below 35 ° C. and reversibly changed to yellow above 35 ° C.
Moreover, as a result of testing the light fastness of this coated product using a fade meter, sun exposure, and a fluorescent lamp, the light fastness superior to that of Example 4 was shown as shown in Table 1 below.

(Example 10)
On the thermochromic coating obtained in Example 5, as a light-resistant protective film, R-073-PEU2 (ultraviolet curable paint containing acicular iron oxide particles having an average primary particle diameter of 0.001 μm: Isam 100 parts of paint (manufactured by Paint Co., Ltd.) was applied by hand spraying at a thickness of 150 g / m ² (dry thickness 45 μm), irradiated with a 1 kW metal halide lamp for 10 seconds and cured with ultraviolet rays, and extremely excellent in light resistance. An excellent temperature-sensitive discoloration coating was obtained.
The obtained temperature-sensitive color-changing coating exhibited a red color below 35 ° C. and reversibly changed to yellow above 35 ° C.
Further, as a result of testing the light fastness of this coated product with a fade meter, sun exposure, and fluorescent lamp, the light fastness superior to that of Example 5 was shown as shown in Table 1 below.

(Example 11)
In a 200 cc beaker, 1.5 parts of 3-dibutylamino-7- (2-chloroanilino) fluorane, 3 parts of bisphenol A, 10 parts of lauryl palmitate, 10 parts of cetyl alcohol, and tinuvin 326 as a benzotriazole-based UV absorber 5 parts (manufactured by Ciba Geigy Co., Ltd.) and 30 parts of epoxy resin (Epicoat 828: manufactured by Yuka Shell Co., Ltd.) were added and dissolved by heating at 100 ° C. to obtain a temperature-sensitive color-changing solution.
In a 1 liter beaker, 400 parts of 10% ethylene / maleic acid copolymer resin (EMA31: manufactured by Monsanto Co., Ltd.) neutralized and dissolved in NaOH as a protective colloid agent was placed and heated to 95-100 ° C. did.
While stirring the solution of the obtained 1 liter container, the above temperature-sensitive color-changing solution was gradually added and emulsified, and then the speed of the stirrer was adjusted to make the average primary particle diameter of the oil droplets 2 μm. It was adjusted. After adjustment, while continuing stirring, 5 parts of an amine-based curing agent (Epicure U: manufactured by Yuka Shell Co., Ltd.) is gradually added, and the reaction is performed by heating and stirring for 5 hours to include a temperature-sensitive discoloration component. A thermochromic microcapsule was obtained.
Next, 5% sulfuric acid is added to the obtained thermochromic microcapsule solution to adjust the pH to 2.0, thereby adjusting the water dispersibility of the protective colloidal agent ethylene / maleic acid copolymer resin. The function was lowered to make an unstable dispersion system. Subsequently, it was filtered with a filter press to obtain a thermochromic microcapsule having a water content of 40%.
The obtained temperature-sensitive color-changing microcapsules having a water content of 40% were put again in a 1-liter beaker, 400 parts of water was added, and the mixture was heated to 95 to 100 ° C. While stirring the resulting solution, 20 parts of a 50% methylolmelamine aqueous solution was added dropwise as a capsule film agent, reacted for 4 hours, and filtered with a filter press to obtain a thermochromic component having a moisture content of 37%. The temperature-sensitive color-changing microcapsules encapsulated in which the wall film was coated with an epoxy resin and further coated with a melamine resin, that is, double-encapsulated were obtained.
Subsequently, the obtained capsule having a water content of 37% was diluted 10-fold with water and dried using a spray dryer, and the microcapsule was powdered.
20 parts of the powdery thermochromic microcapsules obtained, 20 parts of saturated polyester resin (Byron 300: manufactured by Toyobo Co., Ltd.), 60 parts of cellosolve acetate, Coronate HL (Japan Polyurethane Industry Co., Ltd.) ) Produced) 5 parts of thermosensitive color-changing screen printing ink was printed on a mirror-coated tack paper with a 120 mesh screen plate.
Next, on the printed matter, as a light-resistant protective film, 30 parts of a saturated polyester resin (Byron 200: Toyo Shin Co., Ltd.), 60 parts of cellosolve acetate, 25% spherical α iron oxide particles organic solvent dispersion (average primary particles) A 120-mesh screen version of a light-resistant protective ink containing 10 parts of a diameter 0.03 μm and 5 parts of an isocyanate compound (Coronate HL: manufactured by Nippon Polyurethane Industry Co., Ltd.) as a curing agent so that the dry thickness is 25 μm. Was printed twice and laminated.
Next, a 25 μm PET film provided with an adhesive on one side was laminated for the purpose of improving and protecting the scratching property of the ink.
The obtained thermochromic label exhibited a black color at a temperature lower than 35 ° C. and reversibly changed to a yellow color at 35 ° C. or higher.
The obtained tack label was subjected to a light fastness test using a fade meter, exposure to sunlight, and a fluorescent lamp. As a result, as shown in Table 1 below, the light tack fastness was shown.

(Example 12)
As the temperature-sensitive color changing layer, dry-blended with 4 parts of the temperature-sensitive color-changing microcapsule powder obtained in Example 11, 94 parts of a polyester resin (Mitsui PET J125: manufactured by Mitsui Chemicals) and 2 parts of magnesium stearate 97 parts of polyester resin (Mitsui PET J125: manufactured by Mitsui Chemicals, Inc.), 2 parts of magnesium stearate, 1 part of spherical α iron oxide particles (average primary particle size 0.03 μm) as a light-resistant protective film with a thickness of 250 μm Extruded using a three-layer coextrusion device so that a light-resistant protective film is formed on both sides of the temperature-sensitive discoloration layer with a thickness of 125 μm, and the temperature-sensitive discoloration with a total thickness of 500 μm A sheet in which the layer and the light-resistant protective film were integrated was obtained.
The obtained thermochromic sheet exhibited a black color at a temperature lower than 35 ° C. and reversibly changed to a yellow color at 35 ° C. or higher.
Further, the obtained sheet was subjected to a light fastness test using a fade meter, exposure to sunlight, and a fluorescent lamp. As a result, as shown in Table 1 below, the sheet exhibited extremely excellent light fastness.

(Comparative Example 1)
In a 200 cc beaker, 1.5 parts of 3-dibutylamino-7,8-benzofluorane, 3 parts of bisphenol A, 10 parts of lauryl palmitate and 10 parts of cetyl alcohol are heated and dissolved at 100 ° C. A color changing solution was prepared.
In addition, 400 parts of an aqueous solution of methyl vinyl ether / maleic anhydride copolymer resin (GANTREZ AN-179: manufactured by GAF CHEMICALS) neutralized and dissolved in NaOH as a protective colloid agent is placed in a 1 liter beaker, and 95-100 Heated to ° C.
While stirring the solution in the obtained 1-liter container, the above temperature-sensitive color-changing solution was gradually added and emulsified, the stirring speed was adjusted, and the average primary particle size of the oil droplets was adjusted to 2 μm. .
After the adjustment, while continuing stirring, 200 parts of a 50% methylolmelamine aqueous solution was gradually added as a capsule film agent, followed by heating and stirring for 4 hours to obtain a thermochromic microcapsule solution.
To 20 parts of the resulting temperature-sensitive color-changing microcapsule solution, 80 parts of a clear binder (Matsumin Binder S: manufactured by Matsui Dye Chemical Co., Ltd.) containing an acrylate emulsion as a water-soluble fixing agent was mixed. A temperature-sensitive color-changing ink was obtained.
Next, the obtained temperature-sensitive color-changing ink was printed on a cotton knit using an 80-mesh screen plate and dried to obtain a desired temperature-sensitive color-changing printed cloth.
The obtained printed cloth had a red color below 35 ° C. and turned white at 35 ° C. or higher. The printed cloth was tested for light fastness with a fade meter, sun exposure, and fluorescent lamp. As a result, as shown in Table 1 below, the light resistance was extremely inferior to that of Example 1.

(Comparative Example 2)
A clear binder (Matsumin Binder S: manufactured by Matsui Dye Chemical Co., Ltd.) containing 20 parts of the thermochromic microcapsule solution obtained in Example 1 and an acrylic ester emulsion as a water-soluble fixing agent. Parts were mixed to obtain a thermochromic ink.
Next, the obtained temperature-sensitive color-changing ink was printed on a cotton knit using an 80-mesh screen plate and dried to obtain a desired temperature-sensitive color-changing printed cloth.
As in Example 1, the obtained printed fabric had a red color at less than 35 ° C. and turned white at 35 ° C. or higher. However, the printed fabric was made light-resistant by a fade meter, sun exposure, and fluorescent light. As a result of the robustness test, the light resistance was inferior to that of Example 1 as shown in Table 1 below.

(Comparative Example 3)
A clear binder (Matsumin Binder S: manufactured by Matsui Dye Chemical Co., Ltd.) containing 20 parts of the thermochromic microcapsule solution obtained in Comparative Example 1 and an acrylic ester emulsion as a water-soluble fixing agent. 10 parts of a 25% spherical α iron oxide particle aqueous dispersion (average primary particle size 0.06 μm) were mixed to obtain a temperature-sensitive color-changing ink.
Next, the obtained temperature-sensitive color-changing ink was printed on a cotton knit using an 80-mesh screen plate and dried to obtain a desired temperature-sensitive color-changing printed cloth.
The obtained printed cloth was red at a temperature lower than 35 ° C. and changed to yellow at a temperature higher than 35 ° C., but this printed cloth was tested for light fastness using a fade meter, sun exposure, and a fluorescent lamp. As a result, as shown in Table 1 below, the light resistance was inferior to that of Example 1.

(Comparative Example 4)
10 parts of powder-like thermochromic microcapsules obtained in Example 2 and clear Q-086A (clear coating of acrylic ester / urethane copolymer resin dissolved in organic solvent: Isam coating ( 90 parts by weight), 5 parts of Fixer Q-086B (manufactured by Isamu Paint Co., Ltd.) were blended as an isocyanate curing agent to obtain a temperature-sensitive color-changing paint.
The obtained paint was applied to a 0.5 mm thick iron plate previously coated with a white paint by hand spraying at a thickness of 100 g / m ² and dried at 60 ° C. for 30 minutes to achieve the desired feeling. A thermochromic coating was obtained.
100 parts of clear Q-086A (clear paint of acrylic acid ester / urethane copolymer resin dissolved in organic solvent: made by Isamu Paint Co., Ltd.) as a protective film on the thermochromic coating obtained above. As an isocyanate curing agent, a protective coating mixed with 5 parts of Q-086B (manufactured by Isamu Paint Co., Ltd.) was applied by hand spraying at a thickness of 150 g / m ² and dried and cured at 60 ° C. for 30 minutes. A temperature-sensitive discoloration paint was obtained.
The obtained temperature-sensitive color-changing coating exhibited a red color at temperatures below 35 ° C. and reversibly changed to white at temperatures above 35 ° C. This coating was treated with a fade meter, sun exposure, fluorescent lamp As a result of testing the light fastness, the light fastness was extremely inferior to Example 7 as shown in Table 1 below.

(Comparative Example 5)
10 parts of a powder-like thermochromic microcapsule that develops a black color at less than 35 ° C. obtained in Example 11, clear Q-086A (acrylic ester / urethane copolymer dissolved in an organic solvent) as an oil-soluble fixing agent Resin clear paint: Isamu Paint Co., Ltd. 80 parts, 25% iron oxide petal red pigment organic solvent dispersion (average primary particle size 1.00 μm) 10 parts, isocyanate curing agent Fixer Q-086B ( 5 parts of Isamu Paint Co., Ltd. was blended to obtain a temperature-sensitive color-changing paint.
The obtained paint is applied to a 0.5 mm thick iron plate previously coated with a white paint by hand spraying at a thickness of 100 g / m ² and dried at 60 ° C. for 30 minutes, and temperature-sensitive discoloration. A painted product was obtained.
90 parts clear Q-086A (clear paint of acrylic acid ester / urethane copolymer resin dissolved in an organic solvent: made by Isamu Paint Co., Ltd.) as a protective film on the thermochromic coating obtained above. Protective paint mixed with 10 parts of 25% iron oxide petal red pigment organic solvent dispersion (average primary particle size 1.00 μm) and 5 parts of Q-086B (produced by Isamu Paint Co., Ltd.) as an isocyanate curing agent The film was applied by hand spraying at a thickness of 150 g / m ² (dry thickness 45 μm) and dried and cured at 60 ° C. for 30 minutes to obtain the desired thermochromic coating.
The obtained temperature-sensitive color-changing coating is dirty red at less than 35 ° C., and red at 35 ° C. or more, and the red iron oxide pigment has a high concealing property. The color development of the adhesive composition was inhibited, and the original thermochromic function was hardly exhibited.
Table 1 shows the light resistance of the above Examples and Comparative Examples.

In the evaluation, the half-life was described as the time during which the color density of the thermochromic dye was reduced by half after each test exposure.
Sun exposure was tested by exposing samples to the south in February and May.
The fluorescent lamp used was 30 W x 2 and was irradiated from a distance of 1 m.

From the results of Table 1 above, the following can be said.
(1) When a temperature-sensitive color-changing composition using a combination of a benzotriazole-based ultraviolet absorber and an α-iron oxide particle having an average primary particle size of 0.20 μm or less is used as a light resistance improver (Example 1), the product The light resistance of the (printed fabric) is that when both of these agents are not used (Comparative Example 1), when only a benzotriazole ultraviolet absorber is used (Comparative Example 2), α-oxidation with an average primary particle size of 0.20 μm or less Compared with the case where only iron particles are used (Comparative Example 3), it is greatly improved.
(2) Even if it is a molded product (Examples 3 and 8), the effect of using the sensitivity discoloration structure combined with the above light resistance improver is greatly improved in light resistance. improves.
(3) In the case of the above product (coating material), the printed material (Example 6) on which a light-resistant protective film is further laminated is a printed material (Example 1) that is not provided with a light-resistant protective film. In comparison, the light resistance is further improved.
The lamination effect of such a light-resistant protective film is that other products (iron plate: Examples 2 and 7) (polyethylene resin plate: Examples 3 and 8) (glass plate: Examples 4 and 9) (ABS resin plate: The same occurs in Examples 5 and 10).
(4) Even if it is iron oxide, when the petal iron oxide having a particle diameter larger than the average primary particle diameter of 0.20 μm or more of the present invention is used (Comparative Example 5), the high concealing property of the petal iron oxide And the coloring power inhibits the color development of the thermochromic dye and does not exhibit the function of changing the color depending on the original temperature.
(5) From the above, the sensation of the present invention formulated as a light fastness improver composed of a benzotriazole ultraviolet absorber and an α iron oxide particle having an average primary particle size of 0.20 μm or less in a temperature-sensitive color-changing material. It can be seen that the product containing the thermochromic composition has significantly improved light fastness.
In addition to this, α-iron oxide particles having an average primary particle diameter of 0.2 μm or less, or a light-resistant protective film made of the α-iron oxide particles and a benzotriazole-based ultraviolet absorber are further laminated to further change the temperature sensitivity. It can be seen that the light resistance of the product is improved.

The temperature-sensitive color-changing composition of the present invention can be used for obtaining a product such as a light-fast and temperature-sensitive color-change printed matter, a coated product, a molded product, a printed matter, or a written matter.

Claims (9)

  (I) a temperature-sensitive color-changing material comprising an electron-donating color-forming organic compound, (mouth) an electron-accepting compound, and (c) a color-changing temperature adjusting agent; (d) a benzotriazole-based ultraviolet absorber; A temperature-sensitive discoloration composition comprising a light fastness improver composed of α-iron oxide particles having an average primary particle size of 0.20 μm or less.   The temperature-sensitive color-changing composition according to claim 1, wherein the temperature-color-changing material and the benzotriazole ultraviolet absorber are encapsulated.   The temperature-sensitive color-changing composition according to claim 1 or 2, wherein the α iron oxide particles having an average primary particle size of 0.20 µm or less are spherical fine particle iron oxide pigments obtained by a hydrothermal method.   A thermochromic paint, ink, or a coated product thereof, wherein the thermochromic composition according to claim 1, 2, or 3 is blended.   The temperature-sensitive color-changing coated material according to claim 4, wherein the coated material is a printed material, a printed material, a coated material, a painted material, or a written material.   A thermochromic molded product obtained by molding a molding resin composition containing the thermochromic composition according to claim 1, 2 or 3.   Coating composed of a temperature-sensitive color-changing material comprising (a) an electron-donating color-forming organic compound, (b) an electron-accepting compound, and (c) a color-change temperature adjusting agent, coated with a light-resistant protective film In the article or molded article, the light-resistant protective film contains at least one of (e) a light-resistance improving agent composed of α-iron oxide particles having an average primary particle diameter of 0.20 μm or less and (d) a benzotriazole-based ultraviolet absorber. A temperature-sensitive color-changing coated or molded product, characterized in that both agents are present in the light-resistant protective film and the entire substrate of the coated or molded product.   The temperature-sensitive discoloration coated or molded product according to claim 7, wherein the light-resistant protective film has a thickness of 10 µm or more. The alpha iron oxide particles blended in the thermochromic paint, thermochromic molded product, or light-resistant protective film are 0.1 to 30 parts by weight with respect to 100 parts by weight of the synthetic resin. A thermochromic paint or a thermochromic molded product according to claim 6, 7 or 8.