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US3947276A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for the production of cellulose-based fibres and polynosic fibres having a high resistance to combustion, and fibres and textile articles obtained thereby

Assignee: SNIA Viscosa SpA
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Filing: 1973-10-24
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Granted: 1976-03-30
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Expires: 1993-10-24
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Abstract

Abstract A method is disclosed for producing cellulosic and/or polynosic fibres hag flame-resisting properties, the improvement consisting in the fact that a composite viscose is spun in an acidic bath, said composite viscose being obtained by the association in an aqueous solvent, of cellulose xanthate with a phosphorus and nitrogen compound, dissolved in the same aqueous solvent and capable of being converted, while cellulose is being regenerated in said acidic bath, into a state of substantial insolubility. The phosphorus and nitrogen compound is a compound obtained by reacting a phosphonium derivative with aminoacids and amines and/or ammonia. A preferred compound is tetrakis-hydroxymethylphosphonium chloride. By so doing, an efficient flame-retarding protection is obtained for the fibre without sacrificing the physical properties thereof. Critical quantities, reaction conditions and test results are reported.

Inventors

  • 👤 Francesco Siclari
  • 👤 Pietro Paolo Rossi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 13:03
CPC Classifications
C; C07; C07F; C07F9/00; C07F9/02; C07F9/28; C07F9/54; D; D01; D01F; D01F2/00; D01F2/06; D01F2/08; D01F2/10

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 156 words
A method for the production of fibres and yarns consisting prevailingly of cellulosic compounds having high resistance to the propagation and maintenance of combustion comprising adding to a spinnable cellulosic solution of xanthate of cellulose, the product of reaction with a compound selected from the group consisting of ammonia and amines of tetrakis-hydroxymethylphosphonium with a monomeric aminoacid selected from the group consisting of aminoacetic, sulphanylic, p-amino-benzoic, 12-amino-dodecanoic, 6-aminohexanoic, alpha-aminoisovaleric, and alpha-aminopropionic acid, in solution in an alkaline aqueous solvent, the compound of phosphorus in the last-named solution being enriched with NaOH until its free alkali content is near that of the solution of xanthate of cellulose to which it is added, and being soluble in said solution of xanthate of cellulose, and spinning the mixed solutions through nozzles in a regenerating and coagulating bath, said product in solution being added to said spinnable cellulose solution by feeding it in metered amounts upstream of the spinning nozzles.
Claim 2
Independent Claim 156 words
A method for the production of fibres and yarns consisting prevailingly of cellulosic compounds having high resistance to the propagation and maintenance of combustion comprising adding to a spinnable cellulosic solution of xanthate of cellulose, the product of reaction with a compound selected from the group consisting of ammonia and amines of tetrakis-hydroxymethylphosphonium with a monomeric aminoacid selected from the group consisting of aminoacetic, sulphanylic, p-amino-benzoic, 12-amino-dodecanoic, 6-aminohexanoic, alpha-aminoisovaleric, and alpha-aminopropionic acid, in solution in an alkaline aqueous solvent, the compound of phosphorus in the last-named solution being enriched with NaOH until its free alkali content is near that of the solution of xanthate of cellulose to which it is added, and being soluble in said solution of xanthate of cellulose, and spinning the mixed solutions through nozzles in a regenerating and coagulating bath, said product in solution being added to said spinnable cellulose solution by feeding it in metered amounts upstream of the spinning nozzles.
Claim 3
Dependent Claim 13 words
A method according to claim 1 wherein said phosphonium compound is tetrakis-hydroxymethylphosphonium chloride.
Claim 4
Dependent Claim 49 words
A method according to claim 1, wherein said compound is added to the spinnable cellulosic viscose in such an amount that in regenerated cellulose phosphorus and the nitrogen are present, on analysis, in amounts by weight of from 1.5 to 4% and of from 1% to 3% approximately, respectively.
Claim 5
Dependent Claim 26 words
A method according to claim 1, wherein said compound is added to the spinnable cellulosic viscose in the form of an aqueous solution including carbon disulphide.
Claim 6
Dependent Claim 32 words
A method according to claim 1, wherein said compound is obtained by the reaction of the phosphonium compound with an amine selected from the group consisting of monoethanolamine, diethanolamine, cyclohexylamine and ethylenediamine.
Claim 7
Dependent Claim 23 words
A method according to claim 1, wherein the spinnable cellulosic viscose is mixed with a 20% to 30% aqueous solution of said compound.
Claim 8
Independent Claim 171 words
A method for the production of fibres and yarns consisting prevailingly of cellulosic compounds having high resistance to the propagation and maintenance of combustion, comprising in a first stage reacting a phosphonium compound with a monomeric amino acid selected from the group consisting of amino acetic, sulphanylic, p-aminobenzoic, 12-amino-dodecanoic, 6-aminohexanoic, alpha-aminoisovaleric, and alpha-aminopropionic acids, in a second stage reacting the product obtained from the first stage directly or indirectly with ammonia, stabilizing the product from the second stage with an oxidizing agent, adding the stabilized product to a spinnable cellulosic solution of xanthate of cellulose in which said stabilized product is soluble, before adding the stabilized product to the cellulosic solution enriching the product with NaOH until its free alkali content is near that of the spinnable cellulosic solution to which it is to be added, and spinning the mixture through nozzles in a regenerating and coagulating bath, said stabilized product being introduced in solution into said spinnable cellulose solution by feeding it in metered amounts upstream of the spinning nozzles.
Claim 9
Independent Claim 171 words
A method for the production of fibres and yarns consisting prevailingly of cellulosic compounds having high resistance to the propagation and maintenance of combustion, comprising in a first stage reacting a phosphonium compound with a monomeric amino acid selected from the group consisting of amino acetic, sulphanylic, p-aminobenzoic, 12-amino-dodecanoic, 6-aminohexanoic, alpha-aminoisovaleric, and alpha-aminopropionic acids, in a second stage reacting the product obtained from the first stage directly or indirectly with ammonia, stabilizing the product from the second stage with an oxidizing agent, adding the stabilized product to a spinnable cellulosic solution of xanthate of cellulose in which said stabilized product is soluble, before adding the stabilized product to the cellulosic solution enriching the product with NaOH until its free alkali content is near that of the spinnable cellulosic solution to which it is to be added, and spinning the mixture through nozzles in a regenerating and coagulating bath, said stabilized product being introduced in solution into said spinnable cellulose solution by feeding it in metered amounts upstream of the spinning nozzles.
Claim 10
Dependent Claim 22 words
A method according to claim 7, wherein the first stage is carried out by working at a pH between 3 and 8.5.
Claim 11
Independent Claim 35 words
A method according to claims 7, wherein the first stage is carried out at a temperature between 10° C and 60° C, and the second stage is performed at a temperature not exceeding 50° C.
Claim 12
Dependent Claim 49 words
A method according to claim 7, wherein the oxidizing agent is H 2 O 2 , and the second stage reaction is carried out at a temperature between 10° C and 50° C with quantities of the oxidizing agent ranging from 0.7 to 1.5 mols per atom-gram of phosphorus.
Claim 13
Dependent Claim 142 words
A predominantly cellulosic fibre for the production of yarns, fabrics and textile articles in general, obtained by spinning in an acidic bath a viscose containing a cellulose xanthate solution, and the product of reaction with a compound selected from the group consisting of ammonia and amines of tetrakis-hydroxymethylphosphonium with a monomeric aminoacid selected from the group consisting of aminoacetic, sulphanylic, p-amino-benzoic, 12-amino-dodecanoic, 6-aminohexanoic, alphaaminoisovaleric, and alpha-aminopropionic acids, in solution in an alkaline aqueous solvent, the compound of phosphorus in the last-named solution being enriched with NaOH until its free alkali content is near that of the solution of xanthate of cellulose to which it is added, and being soluble in said solution of xanthate of cellulose, to impart to said fibre, yarn, fabric or article of manufacture, improved combustion resistance properties, and wherein its content of regenerated cellulose is less than 95%.
Claim 14
Dependent Claim 142 words
A predominantly cellulosic fibre for the production of yarns, fabrics and textile articles in general, obtained by spinning in an acidic bath a viscose containing a cellulose xanthate solution, and the product of reaction with a compound selected from the group consisting of ammonia and amines of tetrakis-hydroxymethylphosphonium with a monomeric aminoacid selected from the group consisting of aminoacetic, sulphanylic, p-amino-benzoic, 12-amino-dodecanoic, 6-aminohexanoic, alphaaminoisovaleric, and alpha-aminopropionic acids, in solution in an alkaline aqueous solvent, the compound of phosphorus in the last-named solution being enriched with NaOH until its free alkali content is near that of the solution of xanthate of cellulose to which it is added, and being soluble in said solution of xanthate of cellulose, to impart to said fibre, yarn, fabric or article of manufacture, improved combustion resistance properties, and wherein its content of regenerated cellulose is less than 95%.
Claim 15
Dependent Claim 60 words
A textile fibre according to claim 11, which irrespective of the possible presence of additives, contains regenerated cellulose in an amount not exceeding 93.5% of its total weight, and at least 1.5% and 1%, approximately, of phosphorus and nitrogen, respectively, and which exhibits a substantial homogeneousness in its cross-sections as seen in a simple optical microscopical examination in natural light.
Claim 16
Dependent Claim 39 words
A textile fibre according to claim 11, wherein its cellulose content is between 93.5% and 82%, by weight, its phosphorus content is between 1.5 and 4% by weight, and its nitrogen content is between 1 and 2.7% by weight.

References Cited (Backward Citations)

US2768997A Cited
US2345345A Cited
US2809941A Cited
US3645936A Cited
US3704144A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-03-30 1979-09-29 1980-03-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-03-30 1983-09-29 1984-03-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-03-30 1987-09-29 1988-03-30 $7700.00 Window Closed / Lapsed

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