Proban finish

The Proban finish is of a similar nature and consists of padding with a solution which, to quote an example, is made up as follows 15-8 per cent THPC, 9-5 per cent methyloi melamine, 3-0 per cent triethanolamine, 9-9 per cent urea. The cloth, after impregnation, is dried and baked at 140° to 160°C (284° to 320°F). The fastness to washing of this finish is due to the fact that the phosphorus is contained within a polymer deposited in the fibre of the general structure ... 

More recently it has been found that THPC will react with ammonia to give an insoluble polymer and this has resulted in a simplification of the Proban finish. After padding with THPC the cotton is exposed to ammonia gas followed by immersion in aqueous ammonia. No heat setting is necessary and there is some improvement in wet crease-recovery, suggesting that there is a degree of cross-linking. 

These are water-soluble crystalline compounds sold as concentrated aqueous solutions. The methylol groups are highly reactive (118—122) and capable of being cured on the fabric by reaction with ammonia or amino compounds to form durable cross-linked finishes, probably having phosphine oxide stmctures after post-oxidizing. This finishing process, as developed by Albright Wilson, is known as the Proban process. 

Cotton-polyester blends For blends sometimes finishes, which are successful on one type of fiber, may prove to have antagonistic effect on blends.3 The general rule is to apply finish suitable to the majority fiber present or apply halogen-based coating (see Section 24.5.1.2). Most nondurable finishes for cotton will function on cotton-rich blends with polyester, but not for the polyester rich blend unless some bromine is present.3 Durable treatments such as Proban and Pyrovatex type finishes can be applied on higher cotton content fabrics, e.g., 80 20 cotton/polyester. 

A variation on the THPC-urea system was developed to produce finishes with less stiffness and fibre damage (Proban process). A precondensate is prepared by the careful reaction of THPC with urea. This precondensate is padded onto the fabric and the fabric is dried to a specific moisture content ( 15 %). The fabric is then exposed to ammonia vapours in a special reaction chamber, followed by oxidation with hydrogen peroxide (Fig. 8.13). The polymer that forms is primarily located in the lumen of the cotton fibre. The final finish provides durable flame retardancy to cotton with much improved fabric properties. It is important to note... 

Modified THPC-urea finish ( Proban type) /V-methylol phosponopropionamide finish ( Pyrocatex CP new type)... 

Miners protective clothing usually adopt natural fiber fabric, internationally commonly used natural fiber methods mainly include Proban flame retardant finishing of fabrics and Pyrova-tex CP method of two types (Hu Xing 2008) the former flame retardant, good resistance to... 

Finishes based on these reagents are durable to numerous launderings. This finish is primarily used on work clothing. This finishing process, developed by Albright Wilson (now marketed by Rhodia), is known as the PROBAN process, which employs a precondensate of the phosphonium compoimd with urea (125, 126). 

The tetrakis(hydroxymethyl)phosphonium salts are applied to cellulosic fabric, most commonly as a urea precondensate (Albright Wilson s, now Rhodia s Proban), and cured with ammonia vapor (221-223). The finish, after oxidation by air or hydrogen peroxide, has phosphine oxide structures in a cross-linked amino resin network, probably also lightly linked to the cellulose. This finish is durable to multiple launderings and is used for industrial cotton garments (224). 

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