Claims
- 1. A process of flame retardant treating a fabric composed of 100% cellulosic fibers comprising the successive steps of:
- (1) applying a partial condensate of a tetrakis(hydroxymethyl) phosphonium salt and urea flame retardant to the fabric, ammoniating then oxidizing and drying the fabric to attach a first flame retardant to the fibers; and thereafter
- (2) applying a treatment of unreacted tetrakis(hydroxymethyl) phosphonium salt plus urea, or other difunctional or trifunctional nitrogen-containing reactant or both to the fabric, oxidizing and then drying the fabric to attach a second flame retardant to the fibers,
- the combined applications of the first and second flame retardants to the fabric imparting improved flame resistance, durable to laundering to the fabric.
- 2. The process of claim 1, in which after the first application of each flame retardant the fabric is dried to a moisture content of from 5 to 20% by weight prior to further processing.
- 3. The process of claim 1, in which an insoluble phosphorus polymer is introduced into and around the cotton fibers.
- 4. The process of claim 1, in which the cellulosic fibers are cotton.
- 5. The process of claim 1, in which the treated fabric has a flame resistance as measured by char length according to Method 5903 of Federal Test Method Standard 191A of at most 2.5 inches.
- 6. The process of claim 5, in which the treated fabric has a flame resistance as measured by char length of at most 2.5 inches following 25 launderings, when measured according to Method 5903 of Federal Test Method Standard 191A.
- 7. A 100% cellulosic fabric produced by the process of claim 1, with an LOI value of at least 32% after 50 launderings in soft water.
- 8. A process of flame retardant treating a fabric composed of 100% cotton fibers comprising the successive steps of:
- (1) applying a partial condensate of a tetrakis(hydroxymethyl) phosphonium salt and urea flame retardant to the fabric, ammoniating then oxidizing and drying the cotton fabric to attach a first flame retardant to the cotton fibers; and thereafter
- (2) applying a treatment of unreacted tetrakis(hydroxymethyl) phosphonium salt plus urea, or a difunctional or trifunctional nitrogen-containing reactant or both to the cotton fabric, oxidizing and then drying the fabric to attach a second flame retardant to the fibers,
- the combined applications of the first and second flame retardants to the cotton fabric providing an insoluble phosphorus polymer is introduced into and around the cotton fibers and imparting improved flame resistance, durable to laundering of the cotton fabric.
CROSS-REFERENCE TO RELATED APPLICATIONS
This is a continuation of application Ser. No. 07/446,071, filed Dec. 5, 1989, now abandoned which is a continuation-in-part of Ser. No. 07/195,858, filed May 19, 1988, now U.S. Pat. No. 4,902,300, which is a continuation-in-part of Ser. No. 07,052,937 filed May 22, 1987, now abandoned which is a continuation-in-part of Ser. No. 06/870,892, filed Jun. 5, 1986, now abandoned.
US Referenced Citations (15)
Foreign Referenced Citations (4)
Number |
Date |
Country |
0248553 |
Dec 1987 |
EPX |
0249375 |
Dec 1987 |
EPX |
2933207 |
Oct 1978 |
DEX |
1531830 |
Nov 1978 |
GBX |
Non-Patent Literature Citations (3)
Entry |
Amer Dyestuff Reporter May 6, 1968 Proceed Amer Assn Textile Chemists & Colorists "Study of Fire Retardancy of Polyester/Cotton Sheeting", pp. 40-44. |
Chemical Extracts 40-Textiles vol. 98 1983, p. 81 No. 217132c "Fireproofing of synthetic fabrics" Teijin. |
"Dyeing and Chemical Technology of Textile Fibres" pp. 248-249 Shrink-Resist and other Finishes. |
Continuations (1)
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Number |
Date |
Country |
Parent |
446071 |
Dec 1989 |
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Continuation in Parts (3)
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Number |
Date |
Country |
Parent |
195858 |
May 1988 |
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Parent |
52937 |
May 1987 |
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Parent |
870892 |
Jun 1986 |
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