Flame-retardant curable resin composition, dry membrane, flame-retardant covering membrane, and printed circuit board

Abstract

The invention provides a flame-retardant curable resin composition, a dry membrane, a flame-retardant covering membrane and a printed circuit board, specifically provides a flame-retardant curable resin composition, a dry membrane and a flame-retardant covering membrane which are free from halogen compositions, have little environmental loads, excellent flame resistance and excellent flexibility, and has no exudation of flame retardant during high-temperature pressing, and a printed circuit board having the flame-retardant covering film. The flame-retardant curable resin composition and the like contain (A) a phosphorus-containing acrylate resin which is obtained by reacting at least one of a phosphorus-containing dicarboxylic acid and an acid anhydride thereof with an acrylic ester, (B-1) a carboxyl-containing resin having partial structures selected from bisphenol A structure and the like, (C) a thermosetting composition and (D) a photo-polymerization initiator. In formula (1), R1 and R2 independently and respectively represent monovalent hydrocarbyl having a hydrogen atom number or a carbon atom number being 1 to 6; m and n respectively and independently represent integers being 0 to 4; the dotted line represents that two carboxyls can form an acid anhydride.

Description

technical field [0001] The present invention relates to a flame-retardant curable resin composition, a dry film, a flame-retardant coating, and a printed circuit board. A flame-retardant curable resin composition for a flame-retardant film without oozing out of a flame retardant when pressed, a dry film formed from the composition, and at least one of heat-curing and photo-curing the composition or the dry film The flame-retardant coating obtained by any one, and the printed wiring board provided with this flame-retardant coating. Background technique [0002] Conventionally, for flexible printed circuit boards (FPC), an insulating film coated with an adhesive is punched and laminated to a polyimide film called a cover layer, and then pressed under pressure Thermal curing is performed to form a cover layer on the surface of the flexible substrate on which the circuit is formed. Since the cover layer is made of a low-shrinkage thermosetting resin based on a polyimide film, ...

AI Technical Summary

Problems solved by technology

[0003] However, since punching is performed by pressing, there are disadvantages in that it is difficult to perform microfabrication, and when laminating with a circuit board on which a circuit is formed, the positional alignment accuracy is not good.

[0006] In addition, as a resist composition not containing a halogen compound, for example, a composition containing a specific phosphorus element-containing acrylate and a carboxyl group-containing resin has been proposed, but there is room for improvement in flexibility (see Patent Document 3).

[0007] In addition, as a resist composition not containing a halogen compound, for example, a composition containing a phenoxyphosphazene oligomer and an epoxy acrylate has been proposed. , the flame retardant bleeds out and becomes a problem (refer to Patent Document 4)

Images