Abstract: Condensation products which are obtained by reaction of aromatic hydroxycarboxylic acids with formaldehyde in a first stage and by a subsequent condensation reaction of the products with phenol and/or phenol derivatives in the molar ratio 1:(0.8-21):(0.6-20) are suitable as fixing agents for basic dyestuffs in paper printing.
Type:
Grant
Filed:
September 13, 1978
Date of Patent:
January 13, 1981
Assignee:
Bayer Aktiengesellschaft
Inventors:
Gunther Reitz, Gunther Boehmke, Artur Haus, Martin Meister
Abstract: A color developer for pressure-sensitive copying papers is prepared by mixing a para-substituted difunctional phenol-aldehyde condensate and tri- or higher-functional phenol-aldehyde condensate. The tri- or higher-functional phenol-aldehyde condensate can be modified by a polyvalent metal.
Abstract: A color developer for pressure-sensitive copying paper is prepared by mixing a polyvalent metal salt of a para-substituted difunctional phenol-aldehyde condensate and a tri- or higher-functional phenol-aldehyde condensate and/or a polyvalent metal modified tri- or higher-functional phenol-aldehyde condensate.
Abstract: Phenolic novolak resins are described which are structurally characterized as having from about 55% to about 90% of the available theoretical paraphenyl linkages in the resin chain bridged to a phenyl group. The resin compositions of this invention provide extended resin stability at relatively low temperatures without significant adverse affect on the cure speed at the molding temperature. The resins are especially suited for use in runnerless injection or cold manifold molding processes, but can also be used in transfer, compression and injection molding processes.
Abstract: A resin for coating sand and a resin-coated sand produced therefrom wherein the resin is prepared by incorporating furan into a phenolic novolak resin. In the preferred practice, the resin is produced by reaction of furfuryl alcohol with a phenolic compound at an acid pH to give a furfuryl-phenolic intermediate in a first step, and then, in a second step, reacting the furfuryl-phenolic intermediate with a lower aliphatic aldehyde to produce the resin. The resin-coated sands of the present invention provide unexpectedly improved shakeout and collapsibility characteristics in the shell process.