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:
Aug. 24, 1999
Filed:
Jul. 31, 1997
Robert Cole, West Midlands, GB;
Albright & Wilson UK Limited, West Midlands, GB;
Abstract
A process for the flame-retardant treatment of a cellulosic fabric by impregnating a fabric with an aqueous solution of a tetrakis (hydroxyorgano) phosphonium (THP) and then at least partially drying it. The partially dried impregnated fabric is passed at a speed of 30 to 100 m/minute once through a chamber containing ammonia for a single cure. Both the moisture contained in the fabric and water produced as a by-product of curing are volatilized and condensed on an interior wall of the chamber and flow down the walls to a drain for removal of the condensed water from the apparatus. The process further includes measuring the rate of ammonia in the gas fed into the chamber, determining the ammonia content of the gas and measuring the temperature within the chamber, for maintaining the initial concentration of ammonia in the gas at 70% to 90% by volume and for maintaining the ratio of ammonia input to the THP composition in the range of at least 1.2 to 1, on the basis of ammonia to phosphorus; withdrawing the treated fabric from the chamber, removing at least some of the gas from the chamber; and recycling at least some of the gas back into the chamber.