Abstract: A method and composition for forming investment casting patterns wherein thermally-collapsible microspheres are incorporated into the pattern composition. The patterns can be made either by conventional pattern forming techniques or by solid imaging techniques. After investing the microsphere containing pattern in the ceramic shell, the pattern and shell are heated, causing a collapse of the microspheres and thereby preventing cracking of the shell. The shell is then heated to burn-out the remaining pattern material and fire the shell, thereby creating a mold.

Abstract: A method and composition for forming investment casting patterns wherein thermally-collapsible microspheres are incorporated into the pattern composition. The patterns can be made either by conventional pattern forming techniques or by solid imaging techniques. After investing the microsphere containing pattern in the ceramic shell, the pattern and shell are heated, causing a collapse of the microspheres and thereby preventing cracking of the shell. The shell is then heated to burn-out the remaining pattern material and fire the shell, thereby creating a mold.

Abstract: The invention is directed to a laminate for the preparation of printed circuits by electroless plating of conductive metal thereon which comprisesa. an electrically insulative substrate bearingb. an adherent layer of crosslinked polymeric adhesive, which is insoluble in photodielectric developing solutions, having partially embedded therein finely divided particles of adsorbent which protrude from the adhesive surface away from the substrate, the protrusive surfaces of which are adsorptive with respect to electroless plating catalysts or reductive precursors thereof, andc. a solid layer of photodielectric adherently overlying the layer of adhesive and adsorbent particles.

Abstract: The invention is directed to a laminate for the preparation of printed circuits by electroless plating of conductive metal thereon which comprisesa. an electrically insulative substrate bearingb. an adherent layer of crosslinked polymeric adhesive, which is insoluble in photodielectric developing solutions, having partially embedded therein finely divided particles of adsorbent which protrude from the adhesive surface away from the substrate, the protrusive surfaces of which are adsorptive with respect to electroless plating catalysts or reductive precursors thereof, andc. a solid layer of photodielectric adherently overlying the layer of adhesive and adsorbent particles.

Abstract: Catalytic chemical and biochemical conversion reactions are carried out in a novel compartmentalized catalytic reactor which enables the energy-efficient coupling of the conversion reaction with various energy-consuming post-conversion operations. The catalytic reactor is compartmentalized by means of a multilayer composite membrane comprising a catalytic membrane layer and one or more permselective membrane layers. The arrangement and properties of the membrane layers are such as to enable the free energy change of the conversion reaction to be utilized as the required energy source for effecting various post-conversion operations, including product separation, recovery and enrichment, and second-stage catalytic conversions with unfavorable reaction equilibria.

Abstract: The invention is directed to a laminate for the preparation of a multilayer printed circuit by electroless plating of conductive metal thereon which comprisesa. a substrate having formed on a surface thereofb. a conductive pattern, and,c. overlying the pattern and surrounding substrate areas, a layer of tonable photodielectric material having partially embedded therein finely divided particles of adsorbent which protrude from the layer surface away from the substrate, the protrusive surfaces of which are adsorptive with respect to electroless plating catalysts or reductive precursors thereof.

Abstract: Process of enlarging image areas covered by a stencil or relief image area formed in a photopolymer mask consisting essentially of (a) contacting said image area with a swelling agent and optionally a diluent to effect enlargement, and (b) removing excess swelling agent, i.e., evaporation, air impingement including heating. Additional image enlargement is possible by further contacting the image with a more concentrated swelling agent. The process is particularly useful in enlarging halftone image dots of photopolymer litho masks wherein the halftone image areas consist of hardened upper skins which rest on softer undervolumes having a lesser degree of polymerization or hardening.

Abstract: A high speed, positive-working photopolymer element comprising, in order: (1) a support, (2) a nonphotosensitive layer comprising a hardenable binder (e.g., gelatin) containing a releasable hardener (e.g., glutaraldehyde-bisulfite), and an optional colorant, and (3) a permeable photopolymerizable layer. Imagewise exposure of the photopolymerizable layer is followed by diffusion of an alkali through the nonimage area, releasing the hardener. A subsequent wash-off step produces a positive image of the original.

Abstract: A method and system for analyzing gas concentration by measuring the steady state pressure in a dual membrane cell. A first membrane is exposed to a test gas and a second membrane to a reference gas where the first and second membranes have differing permeabilities. The test gas and the reference gas continuously counterdiffuse through the membranes and the steady state pressure in the intermembrane space is directly proportional to the gas concentration of the test gas component.

Abstract: A positive-working imaging element is described comprising a support coated first with a negative-working, solvent-developable, photohardenable stratum, then over-coated with a second negative-working, solvent-developable, photohardenable stratum; the second stratum serves as a mask for the first stratum since it contains ingredients which strongly absorb radiation actinic to the first stratum. The second stratum is imagewise exposed, solvent developed, and the resulting actinically opaque image used as a negative in exposing the first stratum, which is solvent developed to remove the composition in unexposed, but not in exposed areas. Optionally, a separating layer can be present between the photohardenable strata and a cover layer can be present over the second stratum. Positive-working low relief images suitable for lithographic printing plates, printed circuit resists, and contact-speed lithographic films are obtained from the elements of this invention.