Abstract: In one aspect, a single layer polymer film includes 25 to 97.5 wt % of a polyimide having a refractive index of 1.74 or less, 0.5 to 20 wt % of a matting agent and 1 to 30 wt % of a black colorant. On an air side, the single layer polymer film has an L* color of 33 or less and a 60° gloss of 10 or less. In another aspect, a single layer polymer film includes 80 to 99 wt % of a polyimide having a refractive index of 1.74 or less and 1 to 30 wt % of a black colorant. A surface of the single layer polymer film has been textured and has a maximum roughness (Spv) of 7 ?m or more, an L* of 33 or less and a 60° gloss of 10 or less.

Abstract: In a first aspect, a polyimide film includes a substantially chemically converted polyimide and at least 10 volume percent of an inorganic filler, based on a total volume of the polyimide film. A void ratio of the polyimide film is 0.75 or less. In a second aspect, a polyimide film includes a substantially chemically converted polyimide and at least 10 volume percent of an organic filler, based on a total volume of the polyimide film. A void ratio of the polyimide film is 1.0 or less.

Abstract: In a first aspect, a single layer polymer film includes 60 to 99 wt % of a crosslinked polyimide, having a gel fraction in the range of from 20 to 100% and a refractive index of 1.74 or less, and 1 to 40 wt % of a colorant. A surface of the single layer polymer film has been textured and has a maximum roughness (Spv) of 6 ?m or more, an L* color of 30 or less and a 60° gloss of 15 or less. In a second aspect, a coverlay for a printed circuit board includes the single layer polymer film of the first aspect. In third and fourth aspects, processes are disclosed for forming a single layer polymer film including a crosslinked polyimide film including a dianhydride and a diamine.

Abstract: In a first aspect, a single layer polymer film includes 60 to 99 wt % of a crosslinked polyimide, having a gel fraction in the range of from 20 to 100% and a refractive index of 1.74 or less, and 1 to 40 wt % of a colorant. A surface of the single layer polymer film has been textured and has a maximum roughness (Spv) of 6 ?m or more, an L* color of 30 or less and a 60° gloss of 15 or less. In a second aspect, a coverlay for a printed circuit board includes the single layer polymer film of the first aspect. In third and fourth aspects, processes are disclosed for forming a single layer polymer film including a crosslinked polyimide film including a dianhydride and a diamine.

Abstract: In one aspect, a single layer polymer film includes 25 to 97.5 wt % of a polyimide having a refractive index of 1.74 or less, 0.5 to 20 wt % of a matting agent and 1 to 30 wt % of a black colorant. On an air side, the single layer polymer film has an L* color of 33 or less and a 60° gloss of 10 or less. In another aspect, a single layer polymer film includes 80 to 99 wt % of a polyimide having a refractive index of 1.74 or less and 1 to 30 wt % of a black colorant. A surface of the single layer polymer film has been textured and has a maximum roughness (Spv) of 7 ?m or more, an L* of 33 or less and a 60° gloss of 10 or less.