Flame retardant treated fabrics with low formaldehyde content

Abstract

The instant invention relates to a textile article comprising a flame-retardant treated fabric including an oxidized polymer obtained from an ammonia curing of a condensate of (i) a tetrakis (hydroxyorgano) phosphonium salt; and (ii) urea or thiourea; followed by an oxidation into phosphine oxide groups of at least one part of the phosphonium groups present on the cured condensate, wherein said flame-retardant treated fabric: —is intended to be used as a stable substrate in which the formation of formaldehyde over the time is inhibited; and —contains less than 1% by weight of phosphorus present in phosphonium groups, based on the total weight of the flame-retardant treated fabric.

1 . A textile article comprising at least one flame-retardant treated fabric including an oxidized polymer obtained from an ammonia curing of a condensate of (i) a tetrakis (hydroxyorgano) phosphonium salt; and (ii) urea and/or thiourea; followed by an oxidation into phosphine oxide groups of at least one part of the phosphonium groups present on the cured condensate,
 wherein said flame-retardant treated fabric:
 is intended to be used as a stable substrate in which the formation of formaldehyde over the time is inhibited; and 
 contains less than 1% by weight of phosphorus present in phosphonium groups, based on the total weight of the flame-retardant treated fabric. 
   
     
     
         2 . The textile article according to  claim 1  wherein the flame-retardant treated fabric contains less than 0.9% by weight of phosphorus present in phosphonium groups, based on the total weight of the flame-retardant treated fabric. 
     
     
         3 . The textile article according to  claim 1  intended to be in indirect contact with the skin, with a clothing between the treated surface and the skin, that comprises less than 300 ppm. 
     
     
         4 . The textile article according to  claim 1  intended to be in direct contact with the skin, that comprises less than 75 ppm of free formaldehyde. 
     
     
         5 . The textile article according to  claim 1 , wherein the tetrakis (hydroxyorgano) phosphonium salt is tetrakis (hydroxyorgano) phosphonium chloride (THPC). 
     
     
         6 . The textile article according to  claim 1 , wherein the tetrakis (hydroxyorgano) phosphonium salt is tetrakis (hydroxyorgano) phosphonium sulfate (THPS). 
     
     
         7 . The textile article according to  claim 1 , wherein the oxidized polymer is obtained from an ammonia curing of a condensate of (i) a tetrakis (hydroxyorgano) phosphonium salt; (ii) urea and/or thiourea, together with an aliphatic amine having 12 carbon atoms or more; followed by an oxidation into phosphine oxide groups of at least one part of the phosphonium groups present on the cured condensate. 
     
     
         8 . A process for preparing a textile article as defined in  claim 1 , the process comprising:
 (a) a flame retardant treatment of the fabric, including:
 (a1) an impregnation of said fabric with the condensate of (i) a tetrakis (hydroxyorgano) phosphonium salt; and (ii) urea or thiourea, 
 optionally together with an aliphatic amine having 12 carbon atoms or more, 
 (a2) a curing with ammonia of the impregnated condensate; 
 (a3) an oxidation of the polymer resulting from the curing, 
   (b) an analysis of the content of the phosphonium groups in the fabric, followed by a repetition of the sequence of the steps (a3) and (b) if the analysis shows that the fabric contains 1% or more of phosphorus present in phosphonium groups, based on the total weight of the flame-retardant treated fabric.   
     
     
         9 . The process of  claim 8 , wherein in step (b), the analysis is followed by a repetition of the sequence of steps (a3) and (b) if the analysis shows that the oxidized polymer contains 0.9% or more of phosphorus present in phosphonium groups, based on the total weight of the flame-retardant treated fabric. 
     
     
         10 . A process for preparing a textile article as defined in  claim 1 , the process comprising the following steps:
 step 1:   an impregnation of said fabric with the condensate of (i) a tetrakis (hydroxyorgano) phosphonium salt; and (ii) urea or thiourea;   step 2:   a curing with ammonia of the impregnated condensate;   step 3:   an oxidation of the polymer resulting from the curing, said oxidation including and/or being followed by a treatment with a metabisulfite salt at a pH of below 4.   
     
     
         11 . A method, comprising using a flame-retardant treated fabric including an oxidized polymer obtained from an ammonia curing of a condensate of (i) a tetrakis (hydroxyorgano) phosphonium salt; and (ii) urea and/or thiourea; followed by an oxidation into phosphine oxide groups of at least one part of the phosphonium groups present on the cured condensate, wherein said flame-retardant treated fabric contains less than 1% by weight of phosphorus present in phosphonium groups, based on the total weight of the flame-retardant treated fabric, as a substrate stabilized against formation of formaldehyde. 
     
     
         12 . The method according to  claim 11 , wherein the flame-retardant treated fabric is used for a long term contact with the skin. 
     
     
         13 . The method according to  claim 12 , wherein the long term contact with the skin is for more than one year after the synthesis of the oxidized polymer. 
     
     
         14 . The method according to  claim 13 , wherein the long term contact with the skin is for more than two years after the synthesis of the oxidized polymer. 
     
     
         15 . The method according to  claim 14 , wherein the long term contact with the skin is for more than three years after the synthesis of the oxidized polymer. 
     
     
         16 . The textile article according to  claim 3 , comprising less than 200 ppm of free formaldehyde. 
     
     
         17 . The process according to  claim 8 , wherein, in (a3), the oxidation of the polymer resulting from the curing is with H 2 O 2 . 
     
     
         18 . The process according to  claim 8 , wherein, in (b), the analysis of the content of the phosphonium groups in the fabric is by  31 P NMR. 
     
     
         19 . The process according to  claim 10 , wherein, in step 3, the treatment with a metabisulfite salt is at a pH below 3.