Printable substrates with improved brightness from OBAs in presence of multivalent metal salts
US8652593B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 17, 2009 |
| Grant date | Feb 18, 2014 |
| Priority date | — |
| Expiry date | Sep 22, 2030 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21H21/30
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
An article in the form of a paper substrate having a first surface and a second surface; an internal paper sizing agent present in an amount sufficient to impart to the paper substrate an HST value of from about 50 to about 250 seconds; one or more optical brightening agents present in an amount below a “green over” effect excess but sufficient to impart an ISO Brightness value of at least about 92; and a metal salt drying agent mixture of multivalent and monovalent metal drying salts in a molar ratio of multivalent to monovalent cations of from about 3:1 to about 1:18 to provide a percent ink transferred (“IT %”) value equal to or less than about 65% and a black print density value of at least about 1.45. Also, a method for treating the optically brightened paper substrate with a mixture of multivalent and monovalent metal drying salts.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.