Partially halogenated hydantoins in papermaking applications
US6429181B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 30, 2001 |
| Grant date | Aug 6, 2002 |
| Priority date | — |
| Expiry date | Jan 30, 2021 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC02F2103/28
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
The inventors have discovered that partially halogenated hydantoins exhibit superior antimicrobial efficacy and decreased performance additive decomposition rates than fully halogenated hydantoins, such as dichlorodimethyl hydantoin (DCDMH). Partially halogenated hydantoins are solutions containing monochlorohydantoin and, optionally, dihalogenated hydantoin or non-halogenated hydantoin. The present invention is a method of reducing slime in a circulating water slurry comprising organic matter and one or more performance additives, such as optical brighteners, while minimizing decomposition of the performance additives. The method comprises adding one or more partially halogenated hydantoins, such as Cl1.1-chlorodimethyl hydantoin, to the slurry. The concentration of partially halogenated hydantoin maintained in the slurry generally ranges from about 0.01 to about 50 ppm (expressed as Cl2). This method is particularly useful for circulating water slurries in paper processing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.