Screenable and strippable solder mask and use thereof

Claim 1

A screenable, strippable solder mask composition containing: A. a film-forming polymer portion in the form of a liquid composition wherein the film-forming polymer is a polyimide/amide or a liquid polyepoxide; B. a detackifier compatible with the polymer being selected form the group of (1) liquid silicone oil (2) terpene (3) terpineol (4) drying oil, and (5) mixtures thereof; C. a solid high temperature resistant filler in an amount sufficient to render the composition removable from the substrate after solder application; wherein the ratio of A:B is about 2:1 to about 1:3, and provided that when A is a polyepoxide liquid, B includes said silicone oil; and wherein said composition is at least substantially free of hardener for said film-forming polymer.

Claim 29

A method for protecting predetermined areas on a substrate from solder deposition which comprises: A. applying to predetermined areas less than the entire area of a substrate by screen printing a screenable and strippable mask composition containing: (1) a film-forming polymer portion in the form of a liquid composition wherein the film-forming polymer is a polyimide/amide or a liquid polyepoxide; (2) a detackifier compatible with the polymer being selected from the group of (a) liquid silicone oil (b) terpene (c) terpineol (d) drying oil, and (e) mixtures thereof; (3) a solid high temperature resistant filler in an amount sufficient to render the composition removable from the substrate after solder application wherein the ratio of A:B is about 2:1 to about 1:3, and provided that when A is a polyepoxide liquid, B includes said silicone oil; and wherein said composition is at least substantially free of hardener from said film-forming polymer; B. drying the coated substrate to thereby harden the composition; C. applying solder whereby said solder does not adhere to those areas protected by the solder mask; D. removing the solder mask.

Claim 30

A method for protecting predetermined areas on a substrate from solder deposition which comprises: A. applying to predetermined areas less than the entire area of a substrate by screen printing a screenable and strippable mask composition containing: (1) a film-forming polymer portion in the form of a liquid composition wherein the film-forming polymer is a polyimide/amide or a liquid polyepoxide; (2) a detackifier compatible with the polymer being selected from the group of (a) liquid silicone oil (b) terpene (c) terpineol (d) drying oil, and (e) mixtures thereof; (3) a solid high temperature resistant filler in an amount sufficient to render the composition removable from the substrate after solder application wherein the ratio of A:B is about 2:1 to about 1:3, and provided that when A is a polyepoxide liquid, B includes said silicone oil; and wherein said composition is at least substantially free of hardener from said film-forming polymer; B. drying the coated substrate to thereby harden the composition; C. applying solder whereby said solder does not adhere to those areas protected by the solder mask; D. removing the solder mask.