The invention provides a
welding-resistant
photoresist ink composition with the advantages of excellent light hardening force, high alkali wash imaging resolution force and low
dielectric constant. The
printed circuit board welding-resistant ink prepared by using the composition has the advantages of excellent adherence, solution resistance, electrical characteristics, plating resistance, solder
heat resistance, electrical
erosion resistance and the like, the
dielectric constant Dk of the ink is less than 3.20 (1GHz), and the
loss factor Df is less than 0.015(1GHz). The low-
dielectric constant
welding-resistant
photoresist ink composition comprises the following components in percentage by weight: (A) 20-70% of light polymerizable
prepolymer (
oligomer) shown as a formula (1), wherein the
prepolymer is prepared by reacting (a1)
dicyclopentadiene-
phenol polyfunctional
epoxy resin (namely DCPD-
phenol polyfunctional
epoxy resin) or (a2) polyoxyphenylene modified polyfunctional
epoxy resin or (a3)
phenol-
benzaldehyde polyfunctional epoxy resin or any mixture of two of (a1), (a2) and (a3) with (b) monocarboxylic acid containing a vinyl and then reacting with (c) saturated or insaturated polybasic anhydrides; (B) 0-20% of a light polymerizable vinyl
monomer serving as a
diluent; (C) 5-30% of an epoxy resin compound comprising (C1) a
dicyclopentadiene-phenol polyfunctional epoxy resin (namely DCPD-phenol polyfunctional epoxy resin) or polyoxyphenylene modified polyfunctional epoxy resin or phenol-
benzaldehyde polyfunctional epoxy resin or any combination of the three resins, (C2) a tetramethyl diphenol epoxy resin, and (C3) an active ester-based resin; (D) 2-10% of a photo-polymerizatoin initiator; (E) 10-50% of an inorganic filling agent; (F) 0-2.0% of an
accelerant; and (G) 10-40% of an
organic solvent.