Conductive Liquid Composition

Abstract

A conductive liquid composition includes:for a binder resin, 5 to 25 mass % of hydroxyl-containing resin with hydroxyl value 3 to 100 and weight-average molecular weight 4000 to 20000,for a solvent, at least one solvent with a boiling point ≥170° C., ≥70 mass % of the total solvent,for a curing agent, 1.5 to 10.0 mass % of polyisocyanate,(D) for a curing accelerator, 0.005 to 0.1 mass % of an organometallic compound,(E) for an adhesion reinforcing agent, 0.2 to 2.5 mass % of coupling agent,(F) for conducting materials:(f1) 2.0 to 10.0 mass % of graphite,(f2) 5.0 to 15.0 mass % of conductive carbon black, and(f3) 20.0 to 50.0 mass % of silica particles with a mean particle size 1.0 to 7.0 μm and surface-coated with silver, and(G) a surface resistivity 1 to 1000 Ω / sq. when the thickness of the cured film of the conductive liquid composition is 8 μm.

Description

TECHNICAL FIELD[0001]The present invention relates in particular to a conductive liquid composition that can be applied for both flexible plastic film substrates and glass substrates, the conductive liquid composition being usable for antistatic purposes and for electromagnetic wave shields. The invention further relates to a conductive liquid composition having an antistatic function and an electromagnetic wave shield function that exhibits a very excellent leveling property (surface smoothness) as a coated film even with a thin film thickness of about 8 to 10 μm, and also excellent resistance to rinsing with organic solvents such as MEK.BACKGROUND ART[0002]Conductive liquid compositions are used in the production of semiconductor packages and microelectronic devices and in assembly, for various purposes including antistatic functions, electromagnetic wave shield functions and anisotropic conductive adhesive functions (die mounting adhesives and the like).[0003]With the introductio...

AI Technical Summary

Benefits of technology

The invention provides a conductive liquid composition that can be used on both plastic and glass substrates. It has good electromagnetic wave shielding and antistatic properties even at low film thicknesses, and is easy to apply and smooth as a thin coated film. It can withstand rinsing with solvents and is useful for creating coated articles. The technical effects of the invention are improved functionality and reliability in electronic devices, and improved protection against static charge and electromagnetic interference.

Problems solved by technology

Furthermore, as thicknesses decrease as is above described, the coating layers of the conductive liquid compositions are also becoming thinner, and for solid patterns with low thicknesses of about 5 to 10 μm and wide areas (for example, about 50 mm×80 mm), it is becoming increasingly difficult to achieve uniform and highly smooth surfaces for the conductive liquid composition coating layers, which has resulted in the problem of variation in conductive functioning at the coating layer locations.

Incidentally, the surface smoothness of a coated film tends to be improved when the conductive liquid composition coating layer is a thick film of about not less than an extent from 15 to 25 μm, but this solution not only increases the amount of conductive liquid composition used and results in higher cost, but also interferes with the aforementioned decrease in thickness.

However, it is clear from the prior art literature cited below that, as of the current time, no conductive liquid composition has yet been developed that simultaneously exhibits the aforementioned required performance to a satisfactory extent.

Prior Patent Document 1 (Japanese Unexamined Patent Application Publication No. 2015-230847) discloses metal covered particles with high conductivity and a conductive resin composition containing the metal covered particles, but it does not disclose technology relating to a conductive liquid composition that can be used in common for plastic substrates and glass substrates, nor does it disclose technology relating to formation of a coated film with a high degree of surface smoothness even as a thin-film, and able to adequately withstand organic solvent rinsing.

Prior Patent Document 2 (Japanese Patent Public Inspection No. 2016-513143) discloses technology relating to a conductive ink composition that is satisfactory for flexible film substrates, but it does not disclose technology allowing common use for glass substrates as well, or technology relating to formation of a coated film with a high degree of surface smoothness even as a thin-film, and able to withstand organic solvent rinsing.

Prior Patent Document 3 (Japanese Patent Public Inspection No. 2010-539650) discloses a conductive composition including a binder and filler particles with a silver plated core, the composition having a sheet resistivity of not more than about 0.100 Ω / sq. / 25 μm, but it does not disclose technology allowing common use for both plastic substrates and glass substrates, or technology relating to formation of a coated film with a high degree of surface smoothness even as a thin-film, and able to withstand organic solvent rinsing.

However, it does not disclose technology allowing common use for both plastic substrates and glass substrates, nor does it disclose technology relating to formation of a coated film with a high degree of surface smoothness even as a thin-film, and able to withstand organic solvent rinsing.