Process and ink for making electronic devices
View Patent ↗A process for making an electronic device comprising a dielectric substrate laminated with an electrically conductive metal or alloy which comprises applying a non-aqueous etch-resistant ink by ink jet printing to selected areas of the metal or alloy, exposing the etch-resistant ink to actinic radiation and/or particle beam radiation to effect polymerisation, removing exposed metal or alloy by a chemical etching process and then removing the polymerised etch-resistant ink by alkali wherein the etch-resistant ink is substantially solvent free and comprises the components: A) 30 to 90 parts acrylate functional monomers free from acid groups comprising mono or higher functionality wherein 5-95% by weight is one or more mono-functional monomers; B) 1 to 30 parts acrylate functional monomer containing one or more acid groups; C) 0 to 20 parts polymer or prepolymer; D) 0 to 20 parts radical initiator; E) 0 to 5 parts colorant; F) 0 to 5 parts surfactant; and wherein the ink has a viscosity of not greater than 30 cPs (mPa.s) at 40° C. and all parts are by weight.
1. A process for making an electronic device comprising a dielectric substrate laminated with an electrically conductive metal or alloy which comprises applying a non-aqueous etch-resistant ink by ink jet printing to selected areas of the metal or alloy, exposing the etch-resistant ink to actinic radiation and/or particle beam radiation to effect polymerisation, removing exposed metal or alloy by a chemical etching process and then removing the polymerised etch-resistant ink by alkali wherein the etch-resistant ink is substantially solvent free and comprises the components:
A) 30 to 90 parts acrylate functional monomers free from acid groups comprising mono or higher functionality wherein 5-95% by weight is one or more mono-functional monomers;
B) 1 to 30 parts acrylate functional monomer containing one or more acid groups;
C) 0 to 20 parts polymer or prepolymer;
D) 0 to 20 parts radical initiator;
E) 0 to 5 parts colorant;
F) 0 to 5 parts surfactant; and
wherein the ink has a viscosity of not greater than 30 cPs (mPa.s) at 40° C. and all parts are by weight.
2. A process as claimed in claim 1 wherein the amount of mono-functional acrylate monomer is 70-95% by weight of component A).
3. A process as claimed in claim 1 wherein the amount of component B) is not greater than 10 parts.
4. A process as claimed in claim 1 wherein the amount of component B) is not less than 6 parts.
5. A process as claimed in claim 1 wherein component B) is acrylic acid or mono-2-(methacryloyl)ethyl phthalate.
6. A process as claimed in claim 1 wherein the radical initiator is a photoinitiator activated by UV light.
7. A process as claimed in claim 1 wherein the ink has a surface tension of from 20 to 40 mN/m.
8. A process as claimed in claim 1 wherein the viscosity of the ink is from 8 to 20 cPs (mPa.s) at 40° C.
9. A process as claimed in claim 1 wherein component B) has an acid value of not less than 100 mg KOH/g.
10. A process as claimed in claim 1 wherein the total etch-resistant ink has an acid value greater than 30 mg KOH/gm.
11. A process as claimed in claim 1 wherein the amount of polymer or prepolymer (component C)) is zero.
12. A process as claimed in claim 1 wherein the amount of radical initiator is not less than 0.1 parts.
13. A process as claimed in claim 1 wherein the number of parts of components A)+B)+C)+D)+E)+F)=100.