Novel paper coating composition

• US 3,942,995 A
• Filed: 01/22/1973
• Issued: 03/09/1976
• Est. Priority Date: 01/25/1972
• Status: Expired due to Term

• Current Assignee: Kanegafuchi Chemical Industry Co. Ltd. (Kaneka Corporation)
• Original Assignee: Kanegafuchi Chemical Industry Co. Ltd. (Kaneka Corporation)
• Inventors: Adachi, Norihiko, Ichikawa, Atsushi, Kawanabe, Masayoshi, Hisada, Yozi, Kohzaki, Yuichi
• Primary Examiner(s): Morris, Theodore
• Application Number:
  US05/325,797
• Time in Patent Office: 1,142 Days
• Field of Search: 260/6-8, 106/124, 106/170, 106/193, 106/148, 106/149
• US Class Current: 106/145.1
• CPC Class Codes: D21H 19/50 Proteins

Abstract

A paper coating composition comprising (A) a pigment as a main ingredient and (B) a binder for said pigment which is either (a) an alkali decomposition product of a yeast or (b) a mixture of said alkali decomposition product of a yeast and an emulsion of a synthetic polymer and/or an aqueous solution of a natural or snythetic polymer and the paper coating composition coated paper product are disclosed.

Claims

1. A paper coating composition comprising (A) a pigment as a main ingredient and (B) as a binder for said pigment an alkali decomposition product of a yeast produced by heating said yeast with alkali at 30°

-100°

C for ten minutes to ten hours, said yeast being decolored prior to alkali decomposition with sodium boron hydrate as a reducing agent.

2. The composition of claim 1 wherein the amount of said binder is 5 to 50 parts by weight per 100 parts by weight of said pigment.

3. The composition of claim 1 wherein said yeast is selected from the group consisting of baker'"'"'s yeasts, nucleic acid yeasts, beer yeasts, pulp yeasts, and yeasts which assimilate petrochemical products.

4. The composition of claim 1 wherein said yeast is at least one yeast which assimilates methanol, acetic acid or n-paraffin.

5. The composition of claim 1 wherein said yeast is selected from the group consisting of Saccaromyces genus, Candida genus, Mycotorula genus and Pichia genus.

6. The composition of claim 1 wherein said yeast is heated with the alkali at 60°

to 100°

C for 10 minutes to one hour.

7. The composition of claim 1 wherein said alkali is selected from the group consisting of sodium hydroxide, ammonia, slaked lime, sodium phosphate, sodium carbonate and borax.

8. The composition of claim 1 wherein said alkali is sodium hydroxide, ammonia or a mixture thereof.

9. The composition of claim 1 wherein the amount of the alkali is such that the pH of an aqueous suspension of the yeast reaches at least 8.

10. The composition of claim 9 wherein the pH of an aqueous suspension of the yeast is 9 to 13.

11. The composition of claim 1 wherein said binder is a mixture of said alkali decomposition product of a yeast and an emulsion of a synthetic polymer selected from the group consisting of emulsions of a styrene/butadiene copolymer, butadiene/methyl methacrylate copolymer, styrene/butadiene/methyl methacrylate copolymer, ethylene/vinyl acetate copolymer, polyvinyl acetate, vinyl acetate/acrylate copolymer, styrene/acrylate copolymer and styrene/vinyl acetate copolymer.

12. The composition of claim 1 wherein said binder is a mixture of said alkali decomposition product of a yeast and an aqueous solution of a water-soluble natural or synthetic polymer selected from the group consising of casein, soybean protein, oxidized starch, polyvinyl alcohol and carboxymethyl cellulose.

13. The composition of claim 1 wherein said pigment is selected from the group consisting of clay, titanium oxide, satin white and calcium carbonate.