Classifications

• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06M—TREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
  • D06M11/00—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with inorganic substances or complexes thereof; Such treatment combined with mechanical treatment, e.g. mercerising
  • D06M11/01—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with inorganic substances or complexes thereof; Such treatment combined with mechanical treatment, e.g. mercerising with hydrogen, water or heavy water; with hydrides of metals or complexes thereof; with boranes, diboranes, silanes, disilanes, phosphines, diphosphines, stibines, distibines, arsines, or diarsines or complexes thereof
  • D06M11/05—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with inorganic substances or complexes thereof; Such treatment combined with mechanical treatment, e.g. mercerising with hydrogen, water or heavy water; with hydrides of metals or complexes thereof; with boranes, diboranes, silanes, disilanes, phosphines, diphosphines, stibines, distibines, arsines, or diarsines or complexes thereof with water, e.g. steam; with heavy water
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06M—TREATMENT, NOT PROVIDED FOR ELSEWHERE IN CLASS D06, OF FIBRES, THREADS, YARNS, FABRICS, FEATHERS OR FIBROUS GOODS MADE FROM SUCH MATERIALS
  • D06M13/00—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with non-macromolecular organic compounds; Such treatment combined with mechanical treatment
  • D06M13/10—Treating fibres, threads, yarns, fabrics or fibrous goods made from such materials, with non-macromolecular organic compounds; Such treatment combined with mechanical treatment with compounds containing oxygen
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S264/00—Plastic and nonmetallic article shaping or treating: processes
  • Y10S264/61—Processes of molding polyamide

Definitions

• This invention relates to synthetic linear polymers, and particularly to a process for improving the properties of shaped articles prepared from fiber-forming synthetic linear polyamides.
• This invention is concerned in particular with the new class of filament-forming materials known as synthetic linear polymers described in U. S. Patents Nos. 2,071,250; 2,071,251; 2,071,252 and 2,071,253.
• a characteristic property of these polymers is their crystallinity and the fact that filaments and the like prepared from them can be cold drawn, whereupon they show molecular orientation along the fiber axis.
• the cold drawn filaments are stronger and more elastic than the undrawn' filaments and are therefore more useful in the preparation of yarns and fabrics.
• Other articles prepared from these polymers e. g., bristles, ribbons, sheets, and rods, are likewise improved by cold drawing, cold rolling or other processes which bring about molecular orientation of the molecules.
• a particularly useful subclass of filamentforming linear polymers is that of the polyamides. These are of two types: those obtainable from polymerizable monoaminomonocarboxylic acids and their amide-forming derivatives, including caprolactam, and those obtainable from the reaction of suitable diamines with suitable dibasic carboxylic acids or their amideforming derivatives. The latter type is more fully described in U. S. Patent No. 2,130,948. In these polyamides theamide groups form an integral part of the main chain of atoms. The present invention will be described with particular reference to the polyamides, although it is to be understood that it is not so limited.
• Textile yarns may be shrunk (residual shrinkage removed) by a treatment of the yarns in the relaxed condition with hot water.
• Such treatments are usually accomplished by subjecting the yarn in skeins to the action of hot water whereupon the yarn decreases in length with anaccompanying decrease in residual shrinkageand increase in denier.
• This decrease in length of a textile yarn upon being subjected to a shrinkage treatment will be referred to as process shrinkage.
• This skein process is expensive as it must necessarily be discontinuous; likewise, the necessary v handling tends to degrade the yarn.
• Such a process is particularly objectionable in the case 'of polyamide yarns since they are spun directly from melt at very high spinning speeds making possible efficientand rapid continuous production.
• Another disadvantage in such a process is the decrease in length and increase in denier after shrinkage. This decrease in length and increase in denier may be non-uniform and is not easily controlled.
• the residual shrinkage of such structures is materially reduced, if not substantially eliminated, without subjecting them to process shrinkage.
• a polyamide structure can actually be stretched to a material extent, for example, or more, and set in such a stretched condition with a substantial reduction in residual shrinkage.
• residual shrinkage By the term residual shrinkage "is meant the percentage decrease in length which the filament or yarn undergoes when it is subjected in a relaxed condition to a hot aqueous treatment with or without detergents at temperatures of 95-100 C. for five minutes.
• determining residual shrinkage a measured sample is subjected to the shrinkage treatment described above and dried in a relaxed condition, whereupon its length is determined at the same humidity and tempera ture as the initial measurements and the percentage shrinkage calculated.
• a further object of this invention is the reduction of the residual shrinkage of oriented polyamide filaments, yarns and the like while they are maintained in such a manner that theycannot freely change their linear dimensions.
• Another object of this invention is the provision of a continuous method for removing the residual shrinkage of oriented polyamide filaments without accompanying shrinkage.
• the objects of this invention are accomplished, in general, by setting structures comprising oriented synthetic linear polyamide filaments, yarns, ribbons, sheets or the like by a treatment at elevated temperatures with hydroxylated or non-hydroxylated, non-solvent swelling agents for the polyamide while restraining the filaments, yarns, ribbons, sheetsor the like from any substantial reduction in linear dimensions, and in the case of ribbons and sheets, planar dimensions.
• a treatment at elevated temperatures with hydroxylated or non-hydroxylated, non-solvent swelling agents for the polyamide while restraining the filaments, yarns, ribbons, sheetsor the like from any substantial reduction in linear dimensions, and in the case of ribbons and sheets, planar dimensions.
• Example I A 45-denier, -filament polyhexamethylene adipamide yarn, cold drawn 410% with a Z twist of turns per inch, was wound under a tension of 10 grams, on an aluminum bobbin having a four-inch diameter. The bobbin was then placed in a steam chamber, subjected to saturated steam at 120 C. for 20 minutes and the yarnthen removed from the bobbin. This steamtreatment of the wound yarn set the yarn without noticeably shrinking the same. The residual shrinkage of the treated yarn was determined and found to be 1% as compared with a residual shrinkage of the untreated yarn of 7%.
• Example II A 45-denier, 15-filament polyhexamethylene adipamide yarn, drawn 376% having a twist of 4.5 turns per inch, was wound on a bobbin in the same manner as described in Example I, and was set by submerging the same in boiling water for five minutes. The residual shrinkage of the resultant yarn was 4% as compared with a residual shrinkage of the untreated yarn of 10.2%.
• Example III A woven fabric was constructed using 140 threads per inch of -denier, 10-filament, 10-
• the properties of the treated monofil were determined and found to be: denier, 13,800; tenacity (grams perdenier) 3.7; tensile strength (pounds to break) elongation (to break) 20%.
• the residual shrinkage was less than 0.5%.
• the invention may be practiced continuously by subjecting the yarn to hot-wet treatments while running continuously between rolls running at the same peripheral speed and gripping the yarn so that it cannot shrink. Such treatments may also be applied to ribbons, sheets, and woven fabrics in the same manner. Proper provisions may be made to prevent lateral shrinkage as by gripping belts, etc.
• the yarn can be treated withhot water or steam either at atmospheric or superatmospheric pressures.
• the yarn or fabric may travel will depend on the length of the length of the chamber in which the treatment is applied, the temperature of the setting agents and the reduction in residual shrinkage desired. The higher the temperature of the treatment and the longer the travel of the yarn, the higher the speed of travel permissible to maintain the same reduction in residual shrinkage.
• Organic non-solvent swelling agents for the polyamides are also useful. These may be hydroxylated compounds such as the aliphatic alcohols. Methanol, isopropanol and isobutanol are particularly'useful. Other hydroxyl-containing compounds which are useful include ethyl lactate, dimethyl tartrate, ethyl glycolate, ethanolamine, diacetone alcohol and polyhydric alcohols; e. g., ethylene glycol and glycerol. Useful compounds which do not contain the hydroxyl group include organic amines such as aniline, toluidine, dibutyl amine, etc., as well as nitriles and amides.
• the hydroxylated compounds such as the aliphatic alcohols. Methanol, isopropanol and isobutanol are particularly'useful.
• Other hydroxyl-containing compounds which are useful include ethyl lactate, dimethyl tartrate, ethyl glycolate, ethanolamine, diacetone alcohol and
• agents used according to this invention are that they have a swelling action on the polyamides without dissolving them; that is, they are substantially chemically inert towards polyamides.
• This requirement for a non-solvent, organic swelling agent may be satisfied by a mixture of a solvent and a non-solvent.
• any hot-wet treatment has a setting action on oriented polyamide articles, it is generally preferred to employ temperatures between 65 C. and 175 C. for periods of a few minutes to an hour.
• the setting treatment should be carried out at such a temperature and for such a period of time as to reduce the residual shrinkage of the polyamide structures at least to 75% of that of the unset structure.
• the temperature and period of treatment depend upon the particular polyamide and its physical form and upon the setting agent employed. Generally, the higher the temperature employed the shorter the period that is necessary.
• the degree of setting in a given time is roughly a linear function of temperature. For example, the preferred temperature range for water and saturated steam is 95 C. to 110 C. for times ranging from one to fifteen minutes. A treatment for one minute with saturated steam is approximately equivalent to a five minute treatment with hot water at 95 C. Similarly, a five minute treatment with methanol vapor at 100 C. produces as much setting as thirty minutes liquid treatment at 65 C.
• Dry heat is ineffective as an agent to substantially reduce residual shrinkage where the polyamide structure is held against shrinkage in accordance with the present invention.
• the process of this invention may also be practiced to advantage on articles made from other synthetic linear polymers such as the polyesters.
• the setting of polyamide structures in accordance with the present invention can be definitely discerned in the set structures.
• the setting treatment changes the crystalline characteristics of synthetic linear polyamide structures as evidenced by X-ray investigation.
• the X-ray diffraction patterns which change markedly upon cold drawing become much sharper after the yarn is subjected to the setting treatments of this invention. By X-ray investigation it can therefore be definitely ascertained whether or not a structure has been subjected to the process ofthis invention.
• the step which comprises setting said structures by treating the same with a non-solvent swelling agent for the polyamide at a temperature of between C. and 175 C. for a sumcient period of time to reduce the residual shrinkage of the structure at least to of that of a similar unset structure while preventing substantial reduction in dimension of said structures.
• step 2 which comprises setting said structure by treating the same with a non-solvent swelling agent for the polyamide at a temperature of between 65 C. and C. for a period of l to 15 minutes while preventing substantial reduction in dimension of said structures.

Landscapes

• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Artificial Filaments (AREA)
• Yarns And Mechanical Finishing Of Yarns Or Ropes (AREA)

Priority Applications (3)

Applications Claiming Priority (1)

Publications (1)

Family

ID=23038569

Family Applications (1)

Country Status (3)

Cited By (23)

Families Citing this family (1)

• 0
  • BE BE464210D patent/BE464210A/xx unknown
• 1939
  • 1939-05-06 US US272136A patent/US2307846A/en not_active Expired - Lifetime
• 1946
  • 1946-03-19 FR FR926624D patent/FR926624A/fr not_active Expired

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