JPH05132655A - Adhesive - Google Patents

Abstract

PURPOSE:To provide an adhesive consisting of a coloring composition containing an adhesive material and color fading matter, colored when applied, thus capable of visibly recognizing its coating situation, also not impairing its appearance because of becoming colorless by light irradiation after application. CONSTITUTION:The objective adhesive consists of a coloring composition containing (A) an adhesive material (e.g. vinyl acetate-based adhesive, epoxy- based adhesive, synthetic resin-based adhesive) and (B) a color fading matter, being fadable by light irradiation. For the coloring matter, e.g. a combination of a cyanine-based coloring matter with an organoboron compound such as butyltriphenyl borate is used, ensuring color-fading function to be borne.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive which is colored when applied and becomes colorless upon irradiation with light.

[0002]

2. Description of the Related Art If the adhesive is transparent, it is not possible to know where the adhesive has been applied, so it may be wasteful to apply the adhesive more than necessary. The appearance may be impaired due to the traces remaining.

Therefore, an adhesive has been developed that is colored when applied but colorless after applied. As such an adhesive, for example, UHU stic color
(Mitsubishi Pencil Co., Ltd.) This adhesive is colored when it is contained in a container, but it becomes colorless and transparent when it is left on after applying the adhesive to paper or the like. The composition of this adhesive is currently unknown and the mechanism of its discoloration has not been clarified.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to provide an adhesive that changes from colored to colorless by light irradiation. ..

[0005]

The adhesive of the present invention comprises a coloring composition containing an adhesive material and a color erasable dye, and capable of being erased by irradiation with light, thereby achieving the above object. It

The decolorizable dye used in the adhesive of the present invention is colored in the state where it is not irradiated with light having a specific wavelength, but when it is irradiated with the light, it is absorbed and decolored and becomes transparent. It will be. As the decolorizable dye, there is a cyanine dye, and as such a cyanine dye, the following compounds can be exemplified.

[0007]

[Chemical 1]

[0008]

[Chemical 2]

[0009]

[Chemical 3]

[0010]

[Chemical 4]

[0011]

[Chemical 5]

(In the formula, X represents a halogen atom).

The above cyanine dye requires the presence of a salt of an organic boron compound in order to impart a decolorizing function, and in the coexistence of both, near infrared wavelengths, typically 780 to 780. It has an absorption maximum for light having a wavelength of 880 nm, and particularly absorbs light having a wavelength near 820 nm, and is blue when not irradiated with light having a near-infrared wavelength. When absorbed, it is absorbed, erased and becomes transparent.

Further, in this case, in each of the above formulas, X has a structure in which the organic boron compound residue is substituted.

Examples of the organic boron compound include butyltriphenylborate (Ph ₃ B-nC ₄ H ₉ ), and examples of the salt thereof include ammonium salts. That is, as a salt of an organic boron compound, an ammonium salt of butyl triphenyl borate (eg, tetrabutyl ammonium butyl triphenyl borate)
In the above equations, instead of X, Ph
_The structure is such that ₃ B ⁻ −nC ₄ H ₉ exists as a counter ion.

In this case, the mixture of the cyanine dye represented by formula 1 and the salt of the organoboron compound has an absorption maximum for light having a wavelength of 820 nm, and the cyanine dye represented by formula 2 and the organoboron compound. 828 with a mixture of
The mixture of the cyanine dye and the salt of the organic boron compound represented by Formula 3 has an absorption maximum for light having a wavelength of 8 nm, and the mixture has the absorption maximum for light having a wavelength of 819 nm and is represented by Formula 4. The mixture of the cyanine dye and the salt of the organic boron compound has an absorption maximum for light having a wavelength of 874 nm, and the mixture of the cyanine dye and the salt of the organic boron compound represented by Formula 5 has a wavelength of 785 nm. It has an absorption maximum for the light it has.

The adhesive material used in the present invention includes:
Various conventionally known ones can be used.

Examples thereof include room temperature curable adhesives, thermosetting adhesives, hot melts, pressure sensitive adhesives, and rewet adhesives.

Specifically, vinyl acetate type, polyvinyl alcohol type, polyvinyl acetal type, vinyl chloride type,
Acrylic, polyamide, polyethylene, cellulose and other thermoplastic adhesives; urea, melamine, phenol, resorcinol, epoxy, polyester, polyurethane, polyimide, polybenzimidazole, etc. Adhesives: chloroprene-based, nitrile rubber-based, styrene rubber-based, polysulfide-based, butyl rubber-based, silicone rubber-based synthetic rubber-based adhesives and the like.

In addition to the decolorizable dye and the adhesive material, the coloring composition may contain known solvents (organic solvent, water, etc.), plasticizers, additives and the like.

To prepare the above coloring composition, for example,
It can be obtained by mixing the above-mentioned cyanine dye, a salt of an organic boron compound, an adhesive material and, if necessary, other additives. The adhesive of the present invention is contained in a container which is not irradiated with light during storage and is taken out from the container during use.

When the coloring composition contains the above cyanine dye, a salt of an organic boron compound and an adhesive material, the adhesive composed of the coloring layer composition is blue and changes to colorless by light irradiation. is there. Therefore, the adhesive part coated with this adhesive can be visually recognized as blue, and the color of the adhesive part can be appropriately erased by irradiating the adhesive part with light of a predetermined wavelength.

[0023]

When the adhesive composed of the coloring composition containing the decolorizable dye is applied to the adherend, the adhesive has a color such as blue, so that the trace of the adhesive can be visually confirmed. .. Then, by irradiating the application portion of the adhesive with light that can be absorbed by the decolorizable dye, the adhesive can be decolorized.

[0024]

According to the adhesive of the present invention, since the application state of the adhesive can be visually recognized at the time of use, it is possible to eliminate the useless use of the adhesive, and after applying the adhesive, a predetermined wavelength is applied. Since the color is erased by irradiating this light, the adhesive surface is not visible and the appearance is not spoiled. As described above, since the adhesive application portion can be made colorless by the light irradiation, there is also an advantage that the time to be made colorless can be freely set.

Front Page Continuation (72) Inventor Masatomi Funato 1-2-28 Tamatsukuri, Chuo-ku, Osaka Mita Engineering Co., Ltd. In-house (72) Inventor Kazuhiko Yamamura 1-22 Tamatsukuri, Chuo-ku, Osaka Mita Engineering Co., Ltd.

Claims (1)

[Claims] 1. An adhesive comprising a coloring composition containing an adhesive material and a color erasable dye and capable of being erased by light irradiation.