Alkaline developable liquid photoimageable solder resist ink composition

Claim 1

A composition useful as an alkaline developable liquid photoimageable solder resist ink comprising a photocurable resin, a photopolymerization initiator, a reactive diluent and a solvent, wherein said photocurable resin comprises a reaction product of: (A) an epoxy vinyl ester resin obtained by reacting a cresol novolak epoxy resin and an unsaturated monobasic acid, (B) a polybasic acid anhydride and (C) an alkyl ketene dimer and wherein the hydroxyl value of said photocurable resin is not more than about 10 mg KOH/g.

Claim 17

A method of making a composition useful as an alkaline developable liquid photoimageable solder resist ink, said method comprising: a) preparing a first component of said composition by mixing and kneading the following constituents together in the following ranges so as to produce particles of said component having a size of not greater than 10 µm 1. a UV curable resin      30-70 wt. % 2. a pigment      0.5-2 wt. % 3. an inorganic filler      20-50 wt. % 4. a diluent monomer      3-15 wt. % 5. a polymerization inhibitor      0.1-1.0 wt. % 6. a defoaming agent      0.5-3.0 wt. % b) preparing a second component of said composition by dissolving the following constituents in an organic solvent in the following ranges 1. a thermosetting epoxy resin      10-30 wt. % 2. a first photopolymerization initiator      2-10 wt. % 3. a second photopolymerization initiator      1-7 wt. % 4. a photocuring accelerator      0.5-5 wt. % such that, prior to combining said first and said second components together, each said component retains its stability for an extended period during storage thereof due to the relative unreactivity of each independent component ; and c) combining said first component and said second component in a ratio of between about 100:20 to 100:60 of said first to said second component to form said composition.

Claim 18

A method of making a composition useful as an alkaline developable liquid photoimageable solder resist ink, said method comprising: a) preparing a first component of said composition by mixing and kneading the following constituents together in the following ranges so as to produce particles of said component having a size of not greater than 10 µm 1. a UV curable resin      30-70 wt. % 2. a pigment      0.5-2 wt. % 3. an inorganic filler      20-50 wt. % 4. a diluent monomer      3-15 wt. % 5. a polymerization inhibitor      0.1-1.0 wt. % 6. a defoaming agent      0.5-3.0 wt. % b) preparing a second component of said composition by dissolving the following constituents in an organic solvent in the following ranges 1. a thermosetting epoxy resin      10-30 wt. % 2. a first photopolymerization initiator      2-10 wt. % 3. a second photopolymerization initiator      1-7 wt. % 4. a photocuring accelerator      0.5-5 wt. % such that, prior to combining said first and said second components together, each said component retains its stability for an extended period during storage thereof due to the relative unreactivity of each independent component ; and c) combining said first component and said second component in a ratio of between about 100:20 to 100:60 of said first to said second component to form said composition.