| 摘要 |
PURPOSE:To improve the adhesive strength of a photopolymerizable resin composition to a metallic surface by adding a very small amount of a specified compound to the composition which is used to form a photoresist for a printed wiring board. CONSTITUTION:This photopolymerizable resin composition consists of a thermoplastic polymer for a binder, a cross-linkable monomer having an ethylenic unsatd. group in the molecule, a photopolymn. initiator, and theophylline. Theophylline is a very effective component for improving the adhesive strength of a photoresist to a metallic plate. The amount of the compound contained in the composition depends on the components of the photoresist, the ratio among the components and the hardness of the photoresist after photosetting, and the preferred amount is 0.001-1wt% so as to produce a significant adhesive effect. More than the upper limit of the compound reduces the sensitivity, and less than the lower limit of the compound is liable to cause throwing during solder plating. |
