The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 22, 1982
Filed:
Aug. 27, 1980
Applicant:
Inventors:
Assignee:
Kanzaki Paper Manufacturing Co., Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C08L / ;
U.S. Cl.
CPC ...
521 55 ; 528230 ; 528488 ; 528487 ; 521 64 ; 521187 ;
Abstract
The residual formaldehyde existing in the aqueous dispersion of microcapsules each having a capsule wall of an aldehyde polycondensation resin formed by polycondensation of formaldehyde with an amine in the presence of an acid catalyst is removed by adjusting the aqueous dispersion to an alkaline state, adding to the aqueous dispersion at least one reaction catalyst which is a member selected from the group consisting of metal hydroxides, phosphates, calcium salts and magnesium salts, and then heating and agitating the aqueous dispersion to cause a reaction to remove residual formaldehyde therefrom.