JPH0322259Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an adhesive sheet having heat-sensitive reversible discoloration.

(Prior Art and Problems) Various thermosensitive and reversible color-changing ink compositions that change color depending on temperature have been known and have been put to practical use in the fields of towels, toys, and the like.

Attempts have been made to apply this thermochromism phenomenon to textile products such as clothing, but even when a thermosensitive reversible color-changing ink composition is applied or printed on fabric, the light fastness is low and it is not practical. The inventors of the present invention have developed a heat-sensitive reversible color-changing sheet that has improved the above-mentioned problems.
Already proposed as 240587.

On the other hand, there have been no examples in which a fabric having the above-mentioned heat-sensitive reversible discoloration property has been used in a conventional adhesive tape using a fabric as a base material.

(Means for Solving the Problems) An object of the present invention is to solve the above-mentioned problems and to provide a thermosensitive reversible color-changing pressure-sensitive adhesive sheet that can stably exhibit a thermochromism phenomenon for a long period of time.

The heat-sensitive reversible color-changing adhesive sheet of the present invention has the following configuration. That is, a fiber base layer (A layer), a synthetic resin layer (B layer) containing thermosensitive reversible color-changing ink encapsulated in microcapsules, and a synthetic resin layer (C layer) containing an ultraviolet absorber and/or an antioxidant. This is a heat-sensitive reversible color-changing pressure-sensitive adhesive sheet characterized by having an adhesive applied to one side of a coated fabric, which is a laminated structure consisting of layers).

The fiber base material used in the present invention may be any sheet-like material containing fiber as an essential component.
For example, synthetic fibers such as polyamide and polyester,
Regenerated fibers such as rayon and acetate, cotton, wool,
Examples include woven fabrics, knitted fabrics, non-woven fabrics, etc. made of natural fibers such as silk. These base materials can also be used after being dyed or treated with water repellent treatment. In addition, if a transparent fiber base material is used and the base material side is the outer surface, it can have the function of protecting the coating layer, and has durability against external forces such as abrasion resistance, kneading resistance, and scratch resistance. It is preferable because the properties are improved.

As the heat-sensitive reversible color-changing ink, any substance or composition that changes color reversibly depending on temperature can be used. For example, Japanese Patent Publication No. 51-35414,
Those described in Japanese Patent Publication No. 51-44708 and Japanese Patent Publication No. 57-76072 are used. In order to effectively exhibit the thermochromism phenomenon near room temperature, it is particularly preferable to use a material that changes color at -20 to 50°C. In the present invention, in order to improve light resistance to a level that poses no practical problems, it is essential to disperse these heat-sensitive reversible color-changing inks in a synthetic resin while encapsulating them in microcapsules. Furthermore, by encapsulating heat-sensitive reversible color-changing ink in microcapsules, it has become possible to develop multiple colors independently.

Specific examples of synthetic resins used in the present invention include polyurethane, polyacrylic ester, polymethacrylic ester, polyamide, polyester, ABS resin, polyvinyl chloride, polyolefin, polysulfone, ethylene-vinyl acetate copolymer, and polychlorinated Examples include vinylidene and fluororesin.

In this invention, the ultraviolet absorber and antioxidant are
Although each can be used alone, it is preferable to use both together. As the ultraviolet absorber, benzotriazole-based, oxalamide-based, benzophenone-based, and hindered amine-based ones are preferred. Furthermore, as the antioxidant, hindered phenol type antioxidants are preferred.

These ultraviolet absorbers and antioxidants are preferably contained in the C layer in an amount of 0.01% by weight or more, particularly 0.1 to 7.0% by weight, although it depends on the synthetic resin used.
It is preferable that the content is % by weight.

The thermosensitive reversible color-changing fabric used as the base material of the adhesive tape of the present invention has a three-layer laminated structure as described above, but the entire surface does not necessarily have to be this structure, and a part of it may have this structure. It's fine as long as it's there. It is also possible to combine a normal fabric that does not have heat-sensitive reversible discoloration with a fabric that has heat-sensitive reversible discoloration to change the pattern from plain to patterned or from patterned to plain based on changes in temperature. It is.

In addition, another method of forming the handle is
This can also be achieved by locally destroying the microcapsules using heat, pressure, etc., as described in No. 51-35414.

Since the heat-sensitive reversible color-changing ink used in the present invention is encapsulated in microcapsules, it is possible to change the color to various colors depending on each temperature range.

For example, (1) Ink that changes from white to colorless at -10℃ (2) Ink that changes from yellow to colorless at 0℃ (3) Ink that changes from blue to colorless at 10℃ (4) Ink that changes from red to colorless at 20℃ When layer B is formed by mixing four types of heat-sensitive reversible color-changing inks, each of which is encapsulated in microcapsules, with a synthetic resin, the color changes to gray below -10°C, -10 to 0.
Black at ℃, purple at 0-10℃, red at 10-20℃, 20
It turns colorless at temperatures above ℃, allowing you to enjoy an extremely wide variety of color changes.

Further, in the heat-sensitive reversible color-changing adhesive sheet,
It is preferable to apply the adhesive to the A layer side in order to improve light resistance since the C layer is used outside the B layer.

The heat-sensitive reversible color-changing laminated structure used in the present invention can further improve water repellency and abrasion resistance by providing a separate protective layer as the outermost layer, if necessary. As the protective layer, a synthetic resin layer having wear resistance, such as vinyl chloride, polymethyl methacrylate, polyethyl methacrylate, polyamide,
ABS resin, polyvinylidene chloride, etc. are preferred.
The thickness of each layer varies depending on the purpose of use, but layer B is 10
-40μ, and the C layer is about 3-20μ.

Further, depending on the purpose of use, a matting agent such as titanium oxide or silicon oxide may be added to the layer constituting the outermost layer in an amount of about 0.1 to 10% by weight based on the outermost layer.

The method for applying each layer of the heat-sensitive reversible color-changing laminated structure used in the present invention can be direct coating, transfer coating, gravure coating, etc., and the method for removing the solvent can be either wet or dry.

In the present invention, it is also possible to use the heat-sensitive reversible color-changing laminate structure by applying wrinkles to the surface thereof.

The adhesive used in the present invention can be used as long as it has tackiness at room temperature, strongly adheres to the fabric base material, and does not lose adhesive strength for a long period of time after adhesion. Generally, a mixture of various elastomer bases or various resin bases with tackifiers, fillers, softeners (plasticity), antioxidants, vulcanizing agents, etc. is used. For applications requiring water resistance and weather resistance, a silicone rubber base is preferably used.

As the tackifier, rosin-based resin or tenpen-based resin is preferably used because it improves tackiness. Zinc oxide, aluminum hydroxide, clay, calcium carbonate, titanium oxide, and various pigments are used as fillers to make the adhesive opaque or colored and at the same time increase cohesiveness. In order to prevent deterioration of the adhesive due to oxidation, common antioxidants, such as hindered phenol-based antioxidants, are used. Further, in order to improve solvent resistance, oil resistance, chemical resistance, heat resistance, etc., it is also preferable to use a vulcanizing agent.

The method for applying the adhesive to the fabric base material may be either a thermal calendar coating method or a solvent coating method.

The heat-sensitive reversible color-changing adhesive sheet of the present invention can be processed into any shape such as a tape or a patch.

Example 1 Nylon taffeta (using 70D-68fil) was coated with 100 parts by weight (hereinafter referred to as "parts") of polyester polyurethane Rheocoat 9054 (manufactured by Daiichi Lace Co., Ltd.) and melamine crosslinking agent Supervetsucomin 820J (Dainippon Co., Ltd.). Ink Co., Ltd.) 5 parts, p-toluenesulfonic acid 0.15 parts as a crosslinking accelerator, toluene 35 parts as a solvent.
5% dimethyl formamide (hereinafter referred to as Tinuvin P (manufactured by Ciba Geigy) as an ultraviolet absorber)
1 part DMF) solution, 5% DMF solution of Sumilizer BBM (manufactured by Sumitomo Chemical Co., Ltd.) as an antioxidant
A coating solution consisting of 14 parts was applied at a rate of 35 g/m ² and dried. Next, 30 parts of Superflex 300 (Daiichi Kogyo Seiyaku Co., Ltd.), a thermochromic color S-20-C/# that changes color from red to colorless, was applied with a thermosensitive reversible color-changing ink composition encapsulated in microcapsules. A-103
A coating solution consisting of 150 parts of melamine-based crosslinking agent Sumitex M-3 (manufactured by Sumitomo Chemical Co., Ltd.), and 0.5 part of Sumitekus Quantalizer ACX was applied at 150 g/ ^m2. The B layer was formed by applying the same proportions and drying. In addition, Crisbon 7667 (Dainippon Ink
(manufactured by Sumitomo Chemical Co., Ltd.) 100 parts, 0.7 parts of Tinuvin P (manufactured by Ciba Geigy) as an ultraviolet absorber, 0.5 parts of Sumilizer BBM (manufactured by Sumitomo Chemical Co., Ltd.) as an antioxidant, and 1:1 of DMF and methyl ethyl ketone (hereinafter referred to as MEK). A coating solution consisting of 80 parts of a mixed solvent was applied at a rate of 25 g/m ² and dried to form a C layer, and then impregnated with a 3.5% aqueous solution of Scotch Guard FC-453 (manufactured by Sumitomo 3M Co., Ltd.).
It was squeezed with a mangle to a 40% reduction, dried, and heat-set at 160°C for 30 seconds using a drawing machine to form a coated fabric with three coating layers. Furthermore, to improve the kneading resistance, a 25% ethyl nitrate solution of polymethacrylic acid ester was added to the
After coating at a ratio of g/m ² and drying, the fabric was stretched and set at 160°C for 35 seconds to obtain a thermosensitive reversible color-changing fabric with a surface height of 80°C.

100 parts of acrylic two-component pressure-sensitive adhesive FAINTAKU (manufactured by Dainippon Ink Co., Ltd.), 3 parts of diisocyanate crosslinking agent Coronate HL (manufactured by Nippon Polyurethane Co., Ltd.)
Apply the mixed solution on one side of the separator release paper EKR-78.
-D (manufactured by Soken Kako Co., Ltd.) at a thickness of 150μ, and
After drying at ℃ for 60 seconds, the thermosensitive reversible color changing fabric obtained as described above was laminated with Niprol, and then aged at room temperature for 7 days to obtain a heat sensitive reversible color changing adhesive sheet.

The heat-sensitive reversible color-changing pressure-sensitive adhesive sheet reversibly changed color from red to colorless, and vice versa, depending on the temperature difference. In addition, the light fastness is grade 3 or higher in the JIS L 0842 fade test, and the rubbing resistance is JIS K 6328.
No abnormality in kneading resistance test (1Kg 1000 times), JIS Z
It conformed to the adhesive tape standard of 0109-81.

Example 2 Nylon resin Ultramid IC (manufactured by Bayer)
8 parts metalail/benzene/water (7/3/1)
Dissolved in 100 parts of mixed solvent, and further added 0.05 part of UV absorber Tinuvin P (manufactured by Ciba Geigy) and 0.4 part of antioxidant Irganox 1222 (manufactured by Ciba Geigy).
The mixed coating solution was coated on release paper EV-130-TP-D (manufactured by Soken Kako Co., Ltd.) using a gravure coater.
It was coated and dried to a weight of 50 g/m ² . Urethane emulsion Izerax 40 (manufactured by Hodogaya Chemical Co., Ltd.)
50 parts, Thermochromic Color S-22-C/#B-103 (Matsui Dyes
(manufactured by Sumitomo Chemical Co., Ltd.) 100 copies, Sumitex M-3 (Sumitomo Chemical Co., Ltd.)
(manufactured by) Part 3 and Sumitetsu Quantizer
ACX 0.5 parts, Tinuvin P (Ciba Geigy) 0.05
100 parts of Crisbon 4070 (manufactured by Dainippon Ink Co., Ltd.) and Crisbon NX (manufactured by Dainippon Ink Co., Ltd.) were applied to a transfer film obtained by applying a coating ^solution of 0.5 parts of Irganox 1222 (manufactured by Ciba Geigy) at a rate of 120 g/m 2 and drying. 5 parts (manufactured by Dainippon Ink Co., Ltd.), Tinuvin P (manufactured by Ciba Geigy)
100 g of adhesive consisting of 14 parts of 0.1 part of 5% DMF solution
g/m ² , bonded with 30D-32G nylon tricot dyed fabric, left for 24 hours, and then removed the release paper to create a coated fabric with heat-sensitive and reversible thermochromic properties. It was ablic.

100 parts of acrylic two-component pressure-sensitive adhesive FAINTAKU (manufactured by Dainippon Ink Co., Ltd.), 3 parts of diisocyanate crosslinking agent Coronate HL (manufactured by Nippon Polyurethane Co., Ltd.)
Apply the mixed solution on one side of the separator release paper EKR-78.
-D (manufactured by Soken Kako Co., Ltd.) at a thickness of 120μ, and
After drying at ℃ for 60 seconds, the thermosensitive reversible color changing fabric obtained as described above was laminated with Niprol, and then aged at room temperature for 7 days to obtain a heat sensitive reversible color changing adhesive sheet.

The heat-sensitive reversible color-changing pressure-sensitive adhesive sheet reversibly changed color from green to colorless, and vice versa, depending on the temperature difference. In addition, the light fastness is grade 3 or higher in the JIS L 0842 fade test, and the rubbing resistance is JIS K 6328.
No abnormality in kneading resistance test (1 kg 800 times), JIS Z
It conformed to the adhesive tape standard of 0109-81.

(Effects of the invention) The heat-sensitive reversible color-changing adhesive sheet of the present invention has the characteristic of changing color depending on temperature, and due to the combination of the color tone and color development temperature of the heat-sensitive reversible color-changing ink used, it is difficult to put it into practical use with conventional adhesive sheets. It is now possible to enjoy a variety of color changes caused by temperature differences, which was previously impossible. Moreover, by devising a combination with the color of the object to be adhered to, an even wider variety of colors can be expressed. The heat-sensitive reversible color-changing adhesive sheet can be used, for example, in sports equipment such as serve boards, sailcloths for windsurfing, skis and stockings,
Widely used for clothing such as windbreakers, swimsuits, coats, bags, shoes, hats, gloves, etc.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an example of the structure of the heat-sensitive reversible color-changing adhesive sheet of the present invention. In Figure 1, 1: a synthetic resin layer containing at least one of an ultraviolet absorber and an antioxidant, 2: a synthetic resin layer containing a thermosensitive reversible color-changing ink, and 3: a synthetic resin layer containing at least one of an ultraviolet absorber and an antioxidant. Synthetic resin layer, 4: fiber base material, 5: adhesive, 6: release paper.

Claims (1)

[Scope of utility model registration request] A fiber base material layer (layer A), a synthetic resin layer containing thermosensitive reversible color-changing ink encapsulated in microcapsules (layer B), and a synthetic resin layer containing an ultraviolet absorber and/or antioxidant (layer C). A heat-sensitive reversible color-changing adhesive sheet characterized by having an adhesive applied to one side of a coated fabric, which is a laminated structure consisting of.