Abstract: A process for converting a normally positive working photosensitive composition to a negative working composition. One forms a composition containing an alkali soluble resin, a 1,2 quinone diazide-4-sulfonyl compound and an acid catalyzed crosslinker in a solvent mixture. After drying and imagewise exposing, the composition is baked and developed to produce a negative image.

Abstract: A process for converting a normally positive working photosensitive composition to a negative working composition is disclosed. One forms a composition containing an alkali soluble resin, a 1,2 quinone diazide-4-sulfonyl compound and an acid catalyzed crosslinker in a solvent mixture. After drying and imagewise exposing, the composition is baked and developed to produce a negative image. The image-reversal negative-working photoresists of this invention have superior storage stability and shelf life.

Abstract: A water soluble built-on mask layer is provided on a photoresist composition disposed on a substrate. The photoresist comprises an o-quinone diazide and a novolak or paravinyl phenol resin. The built-on mask layer comprises a water soluble, photobleachable diazonium salt, a coupler for the diazonium salt and an acidic, polymeric, film forming resin such as polystyrene sulfonic acid.

Abstract: A process for converting a normally positive working photosensitive composition to a negative working composition. One forms a composition containing an alkali soluble resin, a 1,2 quinone diazide-4-sulfonyl compound and an acid catalyzed crosslinker in a solvent mixture. After drying and imagewise exposing, the composition is baked and developed to produce a negative image.

Abstract: A method for producing a negative image by coating a substrate with a photosensitive layer containing a blocked hydrophobic polymer capable of deblocking in the presence of an acid, and an oxime sulfonate ester or o-quinone-4-sulfonyl-containing diazide, then imagewise exposing, treating with a gaseous base, removing excess base, overall flood exposing, baking and developing with an aqueous alkaline solution.

Abstract: A process for converting a normally positive working photosensitive composition to a negative working composition. One forms a composition containing an alkali soluble resin, a 1,2 quinone diazide-4-sulfonyl compound and an acid catalyzed crosslinker in a solvent mixture. After drying and imagewise exposing, the composition is baked and developed to produce a negative image.

Abstract: A process for converting a normally positive working photosensitive composition to a negative working composition is disclosed. One forms a composition containing an alkali soluble resin, a 1,2 quinone diazide-4-sulfonyl compound and an acid catalyzed crosslinker in a solvent mixture. After drying and imagewise exposing, the composition is baked and developed to produce a negative image. The image-reversal negative-working photoresists of this invention have superior storage stability and shelf life.

Abstract: A process for forming a multi-level positive working photosensitive element. One forms a composition containing an alkali soluble resin, an o-quinonediazide compound and an in-situ generated acid catalyzed crosslinker in a solvent mixture. After coating on a substrate, drying and partially cross-linking the first layer, a second positive working light sensitive layer is applied. Each light sensitive layer is activated by u.v. radiation in different parts of the spectrum. The top layer is imagewise exposed and developed to form a mask. The second layer is flood exposed through this mask and developed. Each development is conducted with an aqueous alkaline solution.

Abstract: A photosensitive article which comprises a substrate, a first light sensitive layer on the substrate, a polysulfone layer and a second light sensitive layer. The first light sensitive layer preferably comprises a depolymerizable polymethyl methacrylate polymer and the second light sensitive layer preferably comprises on o-quinone diazide in admixture with a water insoluble, aqueous alkaline soluble binder resin.

Abstract: A light sensitive composition for the preparation of a positive acting photoresist which is a mixture of an alkali soluble resin and a compound of the formula ##STR1## wherein X is a naphthoquinone-(1,2)-diazide-(2)-sulfonyl residue.