Mask film, its manufacturing method, and manufacturing method of circuit board using the same
AssigneeMatsushita Electric Industrial Co., Ltd.
InventorsToshiaki Takenaka, Toshikazu Kondo, Kunio Kishimoto, Shinji Nakamura, Fumio Echigo
Life of this patent
Estimating the term…
Abstract
A mask film includes a base material, a parting layer and a non-parting portion placed on the base material. Accordingly, an optimum adhesion strength of the mask film and a prepreg sheet can be maintained, and peeling between the mask film and prepreg sheet can be prevented. Further, by preventing the fusing adhesion between the mask film and prepreg sheet due to heat generated when forming penetration holes, a circuit board having an excellent quality is obtained.
Claims48
A mask film for manufacturing a circuit board comprising:
- a base material, and
- a parting layer and a non-parting portion placed on said base material.
A manufacturing method of mask film for manufacturing circuit board comprising the steps of:
- (a) applying a resin mixed solution at a specified position on a base material,
- in which said resin mixed solution contains a solvent, an epoxy resin dissolved in said solvent, and a melamine hardener dissolved in the solvent, and
- the applied resin mixed solution has a specified pattern, and
- (b) forming a parting layer by drying and curing the applied resin mixed solution,
- in which the region excluding the parting layer forms a non-parting portion.
A manufacturing method of circuit board comprising the steps of:
- (a) forming a mask film, in which said mask film comprises a base material, a parting layer and a non-parting portion placed on the base material,
- (b) adhering said mask film to both sides of a prepreg sheet, in which both parting layer and non-parting portion are adhered to said prepreg sheet,
- (c) forming a penetration hole in specified positions of the prepreg sheet having the mask film,
- (d) filling the penetration hole with conductive paste from the mask film side, using the mask film as a mask,
- (e) parting the mask film from the prepreg sheet,
- (f) a step of overlaying metal foils on both sides of the prepreg sheet,
- (g) heating and pressing the prepreg sheet having the metal foils, and adhering the prepreg sheet and metal foils mutually, so that the metal foils placed at both sides are connected electrically with each other through the conductive paste filling up the penetration hole, and
- (h) etching the metal foils selectively to form a circuit pattern.
The manufacturing method of circuit board of claim 46, wherein said adhesion strength adjusting pattern has a plurality of linear patterns placed parallel to the length direction of the base material.
The manufacturing method of circuit board of claim 46,
- wherein said adhesion strength adjusting pattern has
- an air invasion preventing pattern formed parallel to the longitudinal direction of the base material and formed at the inner side of a specific distance from the end of the base material, and
- a discontinuous pattern formed vertically to the longitudinal direction of the base material.
Dependencies are inferred from the claim text.