JPH0132871B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an adhesive tape with good thermal conductivity. Adhesive tapes and sheets made of paper, cloth, plastic film, metal foil, etc. coated with a pressure-sensitive adhesive on one side have been used for a wide range of purposes such as packaging materials, corrosion-resistant materials, and electrical insulation materials. This is an adhesive tape or adhesive sheet that easily adheres to various types of adherends simply by contacting them, permanently and firmly adheres to the adherend, or can be peeled off without leaving any adhesive on the adherend. This is largely due to the convenience of use. However, in recent years, due to the diversification and increasing luxury of consumer needs, as well as increasing constraints on resources and energy, adhesive tapes and adhesive sheets are now required to offer various benefits in addition to their inherent convenience. It became. One of these is the increasing demand for adhesive tapes and adhesive sheets, which have traditionally been used as insulators, to be used as conductors of heat and electricity. For example, the aluminum foil adhesive tape used for adhering the heat radiation pipes of energy-saving electric refrigerators needs to have as high thermal conductivity as possible. Aluminum foil originally has high thermal conductivity, so in this type of adhesive tape, the thermal conductivity of the pressure sensitive adhesive determines the quality of the thermal conductivity of the tape. Metal foil generally has high thermal conductivity, and in addition to aluminum foil, copper foil and iron foil can be used as base materials for adhesive tapes. Pressure-sensitive adhesives are manufactured from natural rubber, synthetic rubber, polyacrylic acid ester, etc., but all of them are polymeric substances, and the thermal conductivity of polymeric substances differs slightly depending on the type, or the adhesive Although it varies depending on the degree of crosslinking inside, the presence or absence of air bubbles, etc., it can generally be said to be about one hundredth of that of metal. The inventor of the present invention focused on the large difference in conductivity between metals and polymeric substances, and as a result of attempting to combine the two, patent application No.
As disclosed in Japanese Patent Publication No. 2003-112003, a pressure-sensitive adhesive with high thermal conductivity is created by incorporating a certain amount of metal powder into a pressure-sensitive adhesive, and this adhesive is coated on one or both sides of a metal foil. As a result, adhesive tapes and adhesive sheets with good thermal conductivity were completed. The present invention was arrived at as a result of further studies on the concept of adding metal powder to pressure-sensitive adhesives.By uniformly containing metal-containing dyes or pigments in pressure-sensitive adhesives, even better thermal properties can be achieved. The purpose is to obtain conductivity. The pressure sensitive adhesive used in the present invention includes hot melt type, emulsion type, aqueous solution type, rubber type,
Either acrylic type or oligomer type may be used. As metal-containing dyes or pigments, those containing metals in the form of intramolecular complex salts are used, but as a binding metal, copper, which has a high thermal conductivity, is preferable (the thermal conductivity of copper is 0.94 cal/cm, sec, ℃). The structure of the ligand is determined by the solubility in solvents such as water, alcohol, MEK, toluene, and ethyl acetate, depending on the type of pressure-sensitive adhesive. A specific structural example is as follows. The amount of metal dye or pigment added is in the range of 0.1 to 5.0 parts by weight per 100 parts by weight of the pressure-sensitive adhesive. That is, if the amount added is less than the minimum amount, no improvement in thermal conductivity can be obtained, and if the amount added is more than the maximum amount, the inherent adhesive properties of the pressure sensitive adhesive cannot be exhibited, which may result in an unacceptable increase in price. Next, the present invention will be explained by examples. Example: An acrylic solution-based adhesive is used as a pressure-sensitive adhesive, and a metal-containing dye, such as that manufactured by Nippon Kayaku Co., Ltd., is used as a pressure-sensitive adhesive.
Add specified amount of kayaset Blue K-FL, thickness 0.05
A test piece was prepared by coating a soft aluminum foil with a thickness of 0.04 mm and drying it at 120°C for 3 minutes. Comparative Example The pressure sensitive adhesive of the above example was applied to a soft aluminum foil with a thickness of 0.05 mm to a thickness of 0.04 mm.
The sample was dried for 3 minutes to prepare a test piece. Next, the adhesive pressure and thermal conductivity of these test pieces were measured, and the results are shown in Table 1. 【table】

Claims (1)

[Scope of Claims] 1. An adhesive tape with good thermal conductivity, characterized in that a coating layer of a pressure-sensitive adhesive uniformly containing a metal-containing dye or pigment is formed on one side of a metal foil. 2. The adhesive tape with good thermal conductivity according to claim 1, wherein the metal-containing dye or pigment is 0.1 to 5.0 parts by weight based on 100 parts by weight of the pressure-sensitive adhesive.