Abstract: Actinic (deep ultraviolet, ultraviolet and visible) light sensitive positive photoresist compositions containing a mixture of an alkali-insoluble photoactive compound capable of being transformed into an alkali-soluble species upon exposure to actinic radiation, in an amount sufficient to render the mixture relatively alkali insoluble and a polymer comprising an amount of --CO--NH--CO-- groups, such as maleimide and especially maleimide-substituted styrene copolymers, sufficient to render the mixture readily alkali soluble upon exposure to actinic radiation are disclosed. The preferred copolymers include maleimide/styrene or .alpha.-methylstyrene in a 1:1 molar ratio. The preferred photoactive compound suitable for a positive photoresist composition responsive to deep UV actinic radiation has the formula 18-B in Table I. The present invention also contemplates photosensitive elements and thermally stable photochemically imaged systems based on the actinic light sensitive positive photoresist compositions.

Abstract: A developer composition having a pH in the range of from about 6.5 to about 7.5 comprising in admixture:(a) from about 0.1% to about 20% by weight of the developer of one or more compounds selected from the group consisting of sodium octyl sulfate, sodium tetradecyl sulfate, sodium 2-ethyl hexyl sulfate and ammonium lauryl sulfate; and(b) from about 0.1% to about 30% by weight of the developer of one or more components selected from the group consisting of lithium salts of hydroxy, aryl and alkyl carboxylic acids; and(c) from about 0.1% to about 30% by weight of the developer of one or more compounds selected from the group consisting of potassium salts of hydroxy, aryl and alkyl carboxylic acids; and(d) from about 0.5% to about 3.

Abstract: A photo polymerization initiator composition is disclosed. The composition is comprised of an in admixture with an acridine, initiator compound. The initiator composition is useful is preparing photopolymerizable compositions having increased effective photospeed.

Abstract: Photoresist compositions suitable for deep UV and excimer laser lithography are disclosed that are mixtures of a photoacid and a polymer having imide residues to which acid labile groups are attached. These compositions provide high resolution, high contrast and high sensitivity in the deep UV (wavelength of 250-300 nm), mid-UV (wavelength of 300-350 nm) or conventional (wavelength of 350-450 nm) exposure bands. The compositions are also suitable for exposure at wavelengths commonly associated with excimer laser sources (248, 308 nm) or for exposure by X-radiation.In the compositions disclosed, the imide group ##STR1## can be blocked with certain groups, X, to form compounds containing the structure ##STR2## which have solubility properties different from the unblocked imide. These groups, X, can be cleaved by acid under the proper conditions to regenerate the unblocked imide.

Abstract: A new monomer is used to prepare homo or copolymers containing blocked imide groups which are characterized by deblocking in two stages, first when acid catalyzed and thereafter in aqueous alkaline solutions. Such polymers are, therefore, especially useful in formulating positive photoresist cmpositions. The polymers are combined with a latent photoacid, which when exposed to actinic radiation removes the acid sensitive blocking moiety, preferably an acetal or ketal group, leaving a methylol group or substituted methylol group remaining attached to the nitrogen atom, which groups are subsequenctly removed by exposure to aqueous alkaline developing solutions, leaving only imide groups, ##STR1## The new monomer is a derivative of maleimide in which the imide hydrogen has been replaced with a methylol group, which is subsequently reacted to form an acetal or ketal. Preferred monomers include N-(2,4-dioxa-3,3-dimethylpentyl)-2H,5H-2,5-dioxopyrrole and related compounds.

Abstract: An improved overlay proofing film comprising a substantially transparent polyester base film which is first coated on one or both sides with a non-light sensitive composition having a refractive index of about 1.6, said non-light sensitive composition consisting essentially of a copolymer of polymethyl methacrylate and methacrylic acid, said coated polyester base film having a second coating on either side thereon, said second coating comprising a light sensitive mixture of(a) a resinous binder;(b) a colorant; and(c) a light sensitive material.

Abstract: An apparatus for covering a stern drive aperture in the hull of a boat. It comprises a planar plate having a plurality of arm members projecting outwardly from its sides. It further has a hole completely through the surface of the plate which is encircled by the mouth of a hollow vessel. The apparatus is useful in protecting the exposed parts of a boat engine when the external drive mechanism is removed for storage or shipment.