Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
292 words
A continuous process for manufacturing a white, bright and opaque precipitated urea formaldehyde pigment comprising: (a) supplying on a continuous basis, a urea formaldehyde resin to a plurality of serially connected reaction vessels, said resin having a water tolerance of from about 1.5 to 5.0 and a viscosity of at least about 450 cps at 50% solids, each of said reaction vessels being precharged with an aqueous acid catalyst precipitating bath containing from about 0.125 to 1.5% by volume of a strong mineral acid at a temperature of from about 20°-95° C., (b) reacting the mixture of resin and precipitating bath in said reaction vessels at a resin to water ratio of from about 1:16 to 3:8 under agitation for a period of time of from about 1/2 to 5 hours including the time for addition of the resin to the precipitating bath to permit most of the higher molecular weight fractions of the resin to react and precipitate in the precipitating bath; (c) filtering the precipitated pigment product formed in step (b) from the precipitating bath at a temperature of from about 25° to 70° C., (d) recycling, on a continuous basis the filtrate obtained from step (c), containing the unreacted lower molecular weight fractions of the resin, back into said reaction vessels; and, (e) introducing into the recycled filtrate after each filtering step from about 0.01% to about 0.5% by weight based on the solids of the urea formaldehyde resin supplied to said reaction vessels of a flocculant material selected from the group consisting of a hydrophilic colloid having a molecular weight in the range of from about 100,000 to 100,000,000 and a functional group selected from the class consisting of hydroxyl, carboxylic, amide, amine and quaternary compounds, and acrylamide.
Claim 2
Dependent Claim
292 words
A continuous process for manufacturing a white, bright and opaque precipitated urea formaldehyde pigment comprising: (a) supplying on a continuous basis, a urea formaldehyde resin to a plurality of serially connected reaction vessels, said resin having a water tolerance of from about 1.5 to 5.0 and a viscosity of at least about 450 cps at 50% solids, each of said reaction vessels being precharged with an aqueous acid catalyst precipitating bath containing from about 0.125 to 1.5% by volume of a strong mineral acid at a temperature of from about 20°-95° C., (b) reacting the mixture of resin and precipitating bath in said reaction vessels at a resin to water ratio of from about 1:16 to 3:8 under agitation for a period of time of from about 1/2 to 5 hours including the time for addition of the resin to the precipitating bath to permit most of the higher molecular weight fractions of the resin to react and precipitate in the precipitating bath; (c) filtering the precipitated pigment product formed in step (b) from the precipitating bath at a temperature of from about 25° to 70° C., (d) recycling, on a continuous basis the filtrate obtained from step (c), containing the unreacted lower molecular weight fractions of the resin, back into said reaction vessels; and, (e) introducing into the recycled filtrate after each filtering step from about 0.01% to about 0.5% by weight based on the solids of the urea formaldehyde resin supplied to said reaction vessels of a flocculant material selected from the group consisting of a hydrophilic colloid having a molecular weight in the range of from about 100,000 to 100,000,000 and a functional group selected from the class consisting of hydroxyl, carboxylic, amide, amine and quaternary compounds, and acrylamide.