A thermosetting powder composition which comprises (a) a specific a carboxyl-terminated polyester and (b) a glycidyl group-containing acrylic copolymer. The carboxyl-terminated polyester (a) has an acid number of 15 to 70 mg of KOH/g and must be prepared in two steps. In the first step, a hydroxyl-terminated polyester is prepared from at least one polycarboxylic acid other than 1,4-cyclohexanedicarboxylic acid, and at least one aliphatic or cycloaliphatic polyol and in the second step, the resulting hydroxyl-terminated polyester is esterified with 1,4-cyclohexanedicarboxylic acid exclusively. In addition, the composition of the polyester (a) is very specific: it contains at least 75 mole % of terephthalic acid, at least 10 mole % of 1,4-cyclohexanedicarboxylic acid and at most 14 mole % of at least one other aromatic and/or aliphatic and/or cycloatiphatic polycarboxylic acid, based on a total carboxylic acid content of 100 mole %. The thermosetting powder compositions obtained from polyester (a) and acrylic copolymer (b) are particularly useful to prepare powder paints and varnishes; they produce coatings with a high gloss, excellent mechanical properties, and at the same time, good weatherability.

A photosensitive composition having increased contrast and selectivity, useful in forming high resolution patterns. The composition comprises a phenolic resin, a diazoquinone compound and an aromatic fused polycyclic sulfonic or carboxylic acid, in the form of the free acid and/or an ammonium salt and/or an acid halide, the cation component of the ammonium salt having the formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4, each represent hydrogen, C.sub.1 -C.sub.4 -alkyl or C.sub.1 -C.sub.4 -hydroxyalkyl. In forming a negative pattern, the composition is coated on a substrate and exposed imagewise to ultraviolet radiation, thereafter treated with a silicon compound, whereby the silicon compound is selectively absorbed into the irradiated portions and the nonirradiated portions are then removed by dry etching.

Carboxyl-terminated and hydroxyl-terminated aliphatic polyester compositions derived from 1,4-cyclohexane-dicarboxylic acid, and a glycol component comprising primarily of cycloaliphatic diols and modifying aliphatic glycols, said polyesters being optionally stabilized by the presence of ultraviolet light absorbing compounds and/or hindered amine light stabilizers and being used in powder coating formulations to provide improved weatherability thereto.