Patent · US Expired

Dual layer tablet, method of making and use thereof

US6863830B1 · kind B1 · utility

58Cited by
15References
40Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 21, 2003
Grant dateMar 8, 2005
Priority date
Expiry dateAug 21, 2023

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC02F2303/04
  • WIPO fieldEnvironmental technology
  • WIPO sectorChemistry

Abstract

A method for treating a recirculating water system which comprises introducing into said water system a multifunctional, multilayer tablet, wherein the multilayer tablet comprises a fast dissolving layer and a slow dissolving layer, wherein said fast dissolving layer releases a combination of active ingredients including a member selected from the group consisting of lithium hypochlorite, calcium hypochlorite, trichloroisocyanuric acid (TCCA), anhydrous sodium dichloroisocyanurate, sodium persulfate, potassium persulfate, potassium monopersulfate, sodium monopersulfate, and mixtures thereof, and at least one of a clarifier, chelating agent, sequesterant, algaestat, water softener, algaecide, corrosion inhibitor, scale inhibitor, flocculent, disintegrant, dispersant, colorant, dissolution control agent, fragrance, or surfactant and, wherein said slow dissolving layer includes a member selected from the group consisting of trichloroisocyanuric acid (TCCA), calcium hypochlorite, 1,3-dichloro-5,5-dimethylhydantoin (DCDMH), 1,3-dibromo-5,5-dimethylhydantoin (DBDMH), 1-bromo-3-chloro-5,5-dimethylhydantoin (BCDMH), 1,3-dichloro-5-ethyl-5-methylhydantoin (DCEMH), 1,3-dibromo-5-ethyl-5-meth…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.