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
  • D06M11/58—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 nitrogen or compounds thereof, e.g. with nitrides
  • D06M11/59—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 nitrogen or compounds thereof, e.g. with nitrides with ammonia; with complexes of organic amines with inorganic substances
  • D06M11/61—Liquid ammonia
• • 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
  • D06M11/32—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 oxygen, ozone, ozonides, oxides, hydroxides or percompounds; Salts derived from anions with an amphoteric element-oxygen bond
  • D06M11/36—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 oxygen, ozone, ozonides, oxides, hydroxides or percompounds; Salts derived from anions with an amphoteric element-oxygen bond with oxides, hydroxides or mixed oxides; with salts derived from anions with an amphoteric element-oxygen bond
  • D06M11/38—Oxides or hydroxides of elements of Groups 1 or 11 of the Periodic Table
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06B—TREATING TEXTILE MATERIALS USING LIQUIDS, GASES OR VAPOURS
  • D06B7/00—Mercerising, e.g. lustring by mercerising
  • D06B7/08—Mercerising, e.g. lustring by mercerising of fabrics of indefinite length
• • 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
  • D06M11/73—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 carbon or compounds thereof
  • D06M11/76—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 carbon or compounds thereof with carbon oxides or carbonates
• • 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
  • D06M23/00—Treatment of fibres, threads, yarns, fabrics or fibrous goods made from such materials, characterised by the process
• • 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
  • D06M2101/00—Chemical constitution of the fibres, threads, yarns, fabrics or fibrous goods made from such materials, to be treated
  • D06M2101/02—Natural fibres, other than mineral fibres
  • D06M2101/04—Vegetal fibres
  • D06M2101/06—Vegetal fibres cellulosic

Definitions

• This invention relates to fabrics and the treatment of fabrics and has particular reference to the treatment of fabrics consisting of or containing lyocell fibre.
• Lyocell fibre is a cellulosic fibre formed in a process in which cellulose is dissolved in an aqueous organic solvent without the formation of a derivative and is subsequently solvent-spun.
• Cellulosic fibres are formed into fabrics in a number of different ways. Typically, staple lyocell fibre is spun or twisted to form yarns, which are then converted into fabrics by weaving or knitting.
• the yarns may be formed entirely of lyocell fibres and the fabrics may be formed entirely of lyocell yarns. However, it is possible to produce blended yarns containing less than 100% lyocell - the remaining fibre may be cotton or polyester or any other suitable fibre.
• the fabric can be produced from a mixture of yarns some of which may be 100% lyocell fibre yarns or blended yarns, the remaining yarns can then be either blends or completely different fibres such as polyester or cotton.
• the yarns may be formed of continuous filament lyocell.
• lyocell fabrics by which is meant herein fabrics at least partly formed of yarns containing or consisting exclusively of lyocell fibres, are known for their flexible drape or handle. It is also known, however, that lyocell fabrics do have a tendency to crease when being wet processed (for example in dyeing or in the enzymatic treatments used to produce the so-called "peach-skin" effect on lyocell fabrics). Disclosure of the invention
• a method of treating fabric formed of yarns wherein some at least of the fibres in some at least of said yarns are lyocell fibres comprises the steps of:- (i) maintaining the fabric in a form in which it is free to shrink;
• the preferred swelling agent comprises an alkali such as sodium hydroxide or lithium hydroxide or potassium hydroxide or ammonia.
• the swelling agent may comprise a bicarbonate of an alkali metal such as sodium bicarbonate.
• other swelling agents such as aqueous tertiary amine oxides, typically aqueous N-methylmorpholine N-oxide, may be used as the swelling agent.
• the fabric may be maintained in a state free to shrink by being in woven piece-form.
• the fabric can be placed around a dummy or other cylindrical member so that the fabric does not have any sharp corners .
• the fabric Once the fabric has been treated with a swelling agent such as sodium hydroxide, it is then treated with water so as to dilute the effect of the swelling agent (e.g. sodium hydroxide) . Subsequently, the fabric may be dried for manufacture into garments and subsequent wet processing such as dyeing. Alternatively, the fabric may go straight from the diluting step into a dyeing or other wet processing finishing process.
• a swelling agent such as sodium hydroxide
• the fabric is a woven fabric, but the fabric may alternatively be a knitted fabric, for example a knitted single ersey fabric, for which the setting process may reduce curl in the fabric .
• the fabric may alternatively be a nonwoven fabric, for example a hydroentangled or needle- punched or bonded nonwoven fabric .
• the swelling agent may comprise sodium hydroxide at a concentration in water in the range 3 to 10 per cent, preferably in the range 5 to 9 per cent, further preferably in the range 7 to 8 per cent , by weight .
• the swelling agent may be at ambient temperature or at elevated or reduced temperature.
• the swelling agent should not dissolve the lyocell fibres to such an extent that their structure is destroyed. Higher concentrations of swelling agent increase the dissolution of the cellulose and it is preferred that the cellulose should not be dissolved to a substantial extent, for example 10 per cent.
• the fabric may be processed continuously in piece-form by being passed through a shrinking bath containing the swelling agent and then through an aqueous diluting bath.
• the present invention further provides a dyed fabric comprising yarn comprising lyocell fibre, said fabric having a structure produced by the steps of:-
• the present invention further provides a lyocell fabric wherein said fabric has a uniform separation of fibres, said uniform separation having been obtained by pre-swelling the lyocell fibres in said fabric in an unrestrained condition and setting said pre-swollen fabric .
• the present invention further provides a method of treating fabric comprising yarns comprising lyocell fibres, said fabric being intended for subsequent wet processing, which method comprises the steps of:-
• the present invention further provides a method ofprocessing lyocell fabric containing lyocell fibres which comprises the steps of:-
• the fabric material subjected to the subsequent wet processing may have been made up into the form of garments prior to the subsequent wet processing if it was not in such form prior to pre-swelling.
• lyocell fibre whether said fabrics comprise 100 per cent lyocell fibre or a lesser amount of lyocell fibre, have proved to be extremely popular.
• the present invention provides a method of producing fabrics and treating fabrics which reduces this effect.
• the material, in fabric form is treated with a swelling agent, typically sodium hydroxide, so as to cause swelling of the lyocell fibre in the fabric.
• a swelling agent typically sodium hydroxide
• the amount of sodium hydroxide is so chosen as to result in a swelling in excess of that which occurs during normal wet processing of the fabric but not so high as to destroy the fibres by excessive dissolution. It has been found that, if lyocell fabric is swollen with a swelling agent such as sodium hydroxide and the swelling agent is then diluted, the fabric takes on a set whereby the yarns in the fabric are fixed in a position relative to one another, which reduces the creasing in subsequent wet processing.
• the fabric as a whole shrinks during the swelling process . Because the fabric is in an unrestrained condition this shrinkage can occur.
• an unrestrained or substantially unrestrained condition as used herein is meant a condition in which shrinkage of the fabric is permitted. In other words the fabric, although under a small amount of tension in some cases, can still shrink. The shrinkage is believed to result from the lyocell fibres forming a crimp along their length.
• the fabric having swollen lyocell- containing yarn is washed with water as a diluting agent, the effect of the swelling agent is removed. This means that the fibres shrink.
• the fabric itself does not expand to its original condition so that the fibres and yarns within the fabric are in a relatively spaced state.
• Fig. 1 is a schematic view of an apparatus for carrying out the process of the present invention.
• Fig. 2 is a photograph of a fabric treated by the process of the invention and of an untreated fabric after each had been squashed by hand into a ball whilst in the wet state, released and then left to dry.
• Fig 3 is a graph correlating force required for wet crease pull out with caustic soda concentration for a fabric treatment by the process of the invention for bathwise treatment and pad treatment.
• this shows a fabric 1 passing around a roller 2 and through the nip of a pair of rollers 3 and being pushed down into a bath 4 containing 7 per cent by weight aqueous sodium hydroxide solution 5 at room temperature.
• the fabric runs around a pair of rollers 6,7 and up through the nip of a pair of rollers 8.
• the fabric then passes around guide rollers 9 and 10 before being passed through a bath 11 containing water 12.
• the fabric then passes through the nip of a pair of rollers 13 before passing around a guide 14 for subsequent processing.
• the rollers 3 run more quickly than the rollers 8.
• the fabric passing through the bath 5 is in a substantially unrestrained condition, so that it can shrink as it passes through the sodium hydroxide solution.
• This causes the lyocell fibres in the fabric to swell.
• the fabric is then passed through the bath 11, being pulled by the rollers 13 in a substantially unrestrained condition, so as to dilute the sodium hydroxide by passing the swollen fabric through the bath 11.
• This causes the lyocell fibres to shrink in diameter but the fabric itself does not increase in length, thus forming a slightly looser fabric which can be subsequently processed in wet processing, so as to give less creasing and less creased dyeing.
• the fabric at point 15 can go direct to wet processing such as piece dyeing and/or enzyme treatment.
• the fabric at point 15 can be dried and made into garments prior to wet processing.
• the first sample of fabric was immersed in a solution of 80 g/litre sodium hydroxide in water (8% by weight sodium hydroxide) .
• the sample was then washed and dyed with a reactive dye in an alkaline solution containing 3g/litre sodium hydroxide (0.3% by weight sodium hydroxide).
• the treatment in 8% sodium hydroxide was at room temperature.
• the fabric was then subjected to a wet softness test.
• the actual test comprised a bending length test. In this test a wet strip of fabric is pushed up an incline of
• the invention is capable of producing a fabric having a much softer handle when wet. This is in comparison to the techniques described in published PCT Application W095/24524, which requires fabric to be treated with a cellulase to produce a softening of the mercerised lyocell.
• the preferred range for the sodium hydroxide concentration in the pre-treatment and swelling step is 3% to 10% by weight. As the sodium hydroxide concentration increases, the amount of cellulose dissolved increases and at 10% by weight sodium hydroxide 8% of the cellulose is dissolved. This is about the maximum acceptable for this technique, and the preferred range of 7 to 8% sodium hydroxide gives the optimum combination of improved softness together with a reduction in crease marking and damage marking, whilst having acceptably low levels of cellulose dissolved.
• the invention is of further particular interest in the treatment of non-woven fabrics .
• the swelling treatment and subsequent dilution treatment ' sets ' the structure of the nonwoven fabric so that the fabric is stronger in subsequent wet processing such as dyeing and the fibres in the fabric are less likely to fall out.
• the nonwoven fabric is stronger, it is still softer compared to nonwoven fabrics which have not been given the swelling technique of the present invention.
• the nonwoven fabric is preferably a hydroentangled fabric .
• the softness of the fabric is particularly noticeable when the fabric is wet.
• Two pieces of lyocell fabric were produced, one treated in accordance with the process of the invention by preswelling the fabric with aqueous sodium hydroxide whilst free to shrink and then setting the fabric by diluting the effect of the sodium hydroxide with water, the other not being given the treatment of the invention.
• the two pieces of fabric were then dried and compared.
• the pieces of fabrics and the processing prior to and including the treatment according to the invention were chosen so that in the dried state the pieces of fabric had virtually identical feel to the hand. On being picked up in each hand and squashed into a ball, the two pieces of fabric felt the same in the dry state.
• the difference in properties has a very material effect during wet processing of the bric, i.e. during the dyeing process or during subsequent washing at home of garments made from such fabrics .
• the untreated sample readily creases there is enhanced abrasion of the fabric samples along the ridges formed by the peaks of the creases .
• lyocell is a fibre which has a tendency to fibrillate
• this wet abrasion gives rise to greater fibrillation along the lines of the creases than in the bulk of the fabric. This fibrillation produces a large number of minute fibrils which have a whiter effect optically when the fabric is subsequently dried.
• the handle of the dry fabrics is little different whether the process of the invention has been used or not, and although the handle of the wet fabric is of little significance to the wearer of the eventual garments (with few exceptions clothes are worn dry and if they become wet in use it is unlikely that the user would notice the difference in handle between one wet garment and another compared to the difference between dry and wet garments), the use of the invention means that fabrics can be processed with much less chance of crease marks appearing during dyeing and with much less chance of crease marks appearing during the home washing process. Furthermore, if the fabric samples shown in Figure 2 are merely dried, then the sample on the left tends to dry much flatter whereas the sample on the right tends to dry with the creases built in.
• this effect can be correlated to the force required for wet crease pull-out.
• this force is correlated with caustic soda concentration in the solution of sodium hydroxide used to treat the fabric in the process of the invention, both in bathwise treatment and in pad treatment.

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• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Chemical & Material Sciences (AREA)
• Inorganic Chemistry (AREA)
• Chemical Or Physical Treatment Of Fibers (AREA)
• Medicines Containing Material From Animals Or Micro-Organisms (AREA)
• Treatments For Attaching Organic Compounds To Fibrous Goods (AREA)
• Treatment Of Fiber Materials (AREA)
• Artificial Filaments (AREA)

Applications Claiming Priority (3)

Publications (2)

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ID=10799328

Family Applications (1)

Country Status (11)

Families Citing this family (7)

Family Cites Families (5)

• 1996
  • 1996-09-03 GB GB9618358A patent/GB2316690A/en not_active Withdrawn
• 1997
  • 1997-09-02 AT AT97939011T patent/ATE229586T1/de active
  • 1997-09-02 TR TR1999/00454T patent/TR199900454T2/xx unknown
  • 1997-09-02 KR KR1019997001444A patent/KR20000068297A/ko not_active Ceased
  • 1997-09-02 ES ES97939011T patent/ES2188973T3/es not_active Expired - Lifetime
  • 1997-09-02 PT PT97939011T patent/PT923657E/pt unknown
  • 1997-09-02 DE DE69717828T patent/DE69717828T2/de not_active Expired - Lifetime
  • 1997-09-02 EP EP97939011A patent/EP0923657B1/de not_active Expired - Lifetime
  • 1997-09-02 WO PCT/GB1997/002355 patent/WO1998010132A1/en not_active Ceased
  • 1997-09-02 AU AU41243/97A patent/AU4124397A/en not_active Abandoned
  • 1997-09-02 JP JP51234298A patent/JP3527251B2/ja not_active Expired - Fee Related

Non-Patent Citations (1)

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