POLYESTER MICROFIBER FABRIC AND MANUFACTURING PROCESS THEREFOR

Description

TECHNICAL FIELD

[0001] The present invention relates to a polyester superfine staple fiber fabric and a manufacturing process therefor, belonging to the technical field of fabric production.

BACKGROUND OF THE PRESENT INVENTION

[0002] At present, the commercially available fabric for automotive interiors is mostly made of nylon and acrylic superfine fibers. However, the fabric for automotive interiors, which is made of nylon and acrylic superfine fibers, shows defects such as low emulation and low light resistance.

[0003] The superfine staple fiber fabric is short for superfine fiber polyurethane artificial leather. As a kind of superfine fibers, sea-island superfine fibers are divided into two main types: sea-island filaments and sea-island staple fibers (including figured sea-island staple fibers and unfigured islands-in-sea fibers). The sea-island filaments are usually used to produce, by weaving and knitting, a suede fabric which is applied in production of clothing and apparel. The sea-island staple fibers are usually used to produce, by needling and non-woven processing, a thick artificial leather fabric which is mainly applied in production of shoes, sofas, automotive interiors, apparel and the like.

[0004] Generally, as the ultimate objective, all superfine staple fiber fabrics are produced into high-emulation leather. By an splitting process in which the sea-island fibers are needled and spunlaced to form a matrix of a non-woven structure, the sea portion of the sea-island fibers is dissolved and the island portion thereof is survived. The survived island portion forms, together with the above non-woven structure, a structure similar to collagen bundles of genuine leather. To fix this structure and maintain soft touch feeling, flexible polymer elastomers are introduced as binders that fix this structure.

[0005] In the present processes and techniques for producing a superfine staple fiber fabric, the splitting of the figured sea-island superfine staple fiber fabric is done with liquid caustic soda at a decrement rate. Compared with the splitting of the unfigured islands-in-sea superfine staple fiber fabric with methylbenzene, it is safe and environmentally-friendly. However, for this process, in order to realize the touch feeling close to genuine leather, the fabric has to be impregnated with oily polyurethane to which organic solvents such as DMF are to be added. The addition of organic solvents such as DMF may lead to the following defects.

1. It is very harmful to operators during the production. As a volatile organic solvent, DMF may cause mild and moderate eye and upper respiratory tract irritation. After invading the body, DMF is metabolized by the liver and quickly excreted by the kidneys. The main target organ of DMF is the liver and the kidneys are somewhat damaged. DMF shows moderate toxicity.

2. As a solvent for adjusting polyurethane, there may be residual DMF on the superfine staple fiber fabric although it is washed with water in the subsequent processes, resulting in high VOC value of products and slight odor. Such products do not meet the environmental requirements and can even influence the users' experience.

3. Uncontrolled leakage of DMF may be caused in the case of incorrect operation, which may greatly affect the environment.

4. The treatment of the residual DMF further increases the production cost.

5. By using nylon superfine staple fibers as raw materials, the conventional superfine staple fiber fabric has low color fastness and thus has not yet been applied in high-grade fields such as automotive interiors.

6. Due to the structure of superfine staple fibers, the physical properties of the needled base fabric have congenital defects. It is difficult to improve both the density and the strength. To solve the problems, great efforts have been made by artificial leather research personnel. Among those efforts, a method is proposed, in which woven fabric or knitted fabric is added in non-woven fabric as a base, then superfine staple fibers are laid on the woven fabric or knitted fabric, and finally they are needled, to form a base fabric having a reinforced structure. However, the strength of the woven fabric or knitted fabric, which is used as the base, is significantly decreased due to needling. Their contribution to the increase in the overall strength of artificial leather is limited.

[0006] In view of those defects, the existing processes need to be modified and improved by artificial leather research personnel. A process for manufacturing a superfine staple fiber fabric which is more environmentally-friendly and has higher emulation and higher light resistance.

SUMMARY OF THE PRESENT INVENTION

[0007] To solve the problems mentioned in the Background and to overcome the technical defects, the present invention provides a polyester superfine staple fiber fabric which is more environmentally-friendly and has higher emulation and higher light resistance, and a manufacturing process therefor.

[0008] The present invention employs the following technical solution.

[0009] The present invention provides a polyester superfine staple fiber fabric, comprising upper mesh cloth, a polyester superfine staple fiber non-woven fabric, and lower mesh cloth, which are arranged from top to bottom in sequence. Both the upper mesh cloth and the lower mesh cloth are made of high-strength FDY filaments with 2000-4000 twists and 75-100D/48F. The polyester superfine staple fiber non-woven fabric is made of polyester superfine staple fibers having a denier per filament of 0.15-0.25 dtex.

[0010] The present invention provides a process for manufacturing a polyester superfine staple fiber fabric, comprising steps of:

(1) laying polyester superfine staple fibers having a denier per filament of 0.15-0.25 dtex as raw material, to form a polyester superfine staple fiber layer;

(2) double-sided ribbing the polyester superfine staple fiber layer with mesh cloth made of high-strength FDY filaments with 2000-4000 twists and 75-100D/48F, and needling;

(3) ironing to form grey cloth, wherein the grey cloth has an apparent density of 0.15-0.45 g/cm³;

(4) pre-shrinking the grey cloth in an impregnating tank at 90-100°C for 5-10 min, wherein the shrinkage of the pre-shrinking is to be controlled (at 12-15% in this step), and by pre-shrinking, the density of the fabric can be increased to a high density close to genuine leather and the use amount of PU can be reduced without decreasing the skin feeling close to genuine leather, thereby facilitating the subsequent downy feeling treatment to ensure more delicate downy feeling;

(5) impregnating with water-soluble resin and then drying;

(6) impregnating with water-soluble polyurethane and then drying;

(7) splitting;

(8) wet sanding;

(9) rubbing: after wetting the cloth by water, transferring it into a drum device, wherein steam in the drum is at 85-110°C, the drum swings to and fro between positive 120° and negative 120° , and the drum device finishes the swinging action from the positive to negative direction or from the negative to positive direction within 20s to 40s, wherein by rubbing, the tension between fibers and polyurethane can be released so that the overall softness is better, and the fabric can be further shrunk;

(10) dyeing; and

(11) napping to obtain the finished product.

[0011] As a further arrangement of the solution, in the step (2), the needling is done at a speed of 2-2.5 m/min and at a frequency of 700 times per minute.

[0012] In the step (3), the ironing is done at a speed of 3-4 m/min and at a temperature of 140°C.

[0013] In the step (5), the water-soluble resin has a viscosity of 0-100 cps and a solid content of 15-20%, and a liquid content in the grey cloth is 80-120%; and the drying is done at a temperature of 125-135 °C and at a speed of 5-7 m/min.

[0014] In the step (6), the water-soluble polyurethane has a viscosity of 300-1000 cps and a solid content of 40-50%, and a liquid content in the grey cloth is 150-180%; and the drying is done by three ovens, among which the first oven has a temperature of 110-125°C, the second oven has a temperature of 145-160°C, and the third oven has a temperature of 120-130°C, and at a speed of 3-5 m/min. The initial drying temperature should be as low as possible, but higher than 100°C to facilitate water evaporation. However, it should not be too high. A too high temperature will cause water-soluble polyurethane on the surface to solidify too fast.

[0015] In the step (7), the splitting is done with NaOH having a concentration of 10-30 g/L, at a temperature of 85-110°C, for 45-90 min. Due to the low alkali resistance of polyester fiber, a low-temperature and low-concentration splitting process is used.

[0016] In the step (8), first wet sanding is done by two sand-rollers, both of which are 150-300 meshes; then, second wet sanding is done by one sand-roller which is 300-400 meshes; finally, third wet sanding is done by one sand-roller which is 400-600 meshes; and the wet sanding is done at a speed of 5-10 m/min and all the sand-rollers work at a speed of 1500-2100 revolutions/min. The polyester superfine staple fiber is highly rigid. Consistent downy feeling is provided by coarse sanding (that is, the surface is smoothened) and fine sanding plays a role of combing to ensure uniform and delicate downy feeling on the surface.

[0017] In the step (10), the dyeing is done with a disperse dye by a low-bath-ratio one-bath process, at a bath ratio of 1:8-1:10 and at a temperature of 120-125°C.Water-soluble polyurethane shows high affinity to the disperse dye. The use of the one-bath process can greatly reduce the energy consumption, especially the water consumption, with high production efficiency. Meanwhile, this process can realize high color fastness of products.

[0018] In the step (11), first napping is done by two sand-rollers, both of which are 240-320 meshes; then, second napping is done by two sand-rollers, both of which are 400-600 meshes; finally, carding is done by a carding roller; and the napping is done at a speed of 5-8 m/min and all the sand-rollers work at a speed of 1500-2100 revolutions/min. Due to the use of water-soluble polyurethane, the fabric has great downy feeling and shade. Therefore, the conventional buffing procedure is omitted, and the production and treatment of industrial solid waste are reduced.

[0019] The present invention has the following beneficial effects. The polyester superfine staple fiber fabric of the present invention has skin feeling and downy feeling close to genuine leather, shows high affinity and high color fastness to the disperse dye, and better deep-dyeing, bright-dyeing, aging resistance to light than nylon staple fibers; the replacement of the solvent-based polyurethane with water-soluble polyurethane avoids the generation of substances that are harmful to the human body and the environment during the production; and only slight napping is needed, the buffing procedure is omitted, and the production of industrial solid waste is reduced. Meanwhile, the manufacturing process of the present invention has advantages of short production process, low energy consumption and high production efficiency.

[0020] The polyester superfine staple fiber fabric of the present invention has the following main technical indicators:

(1) color fastness to acid perspiration (grade): color change: 4; staining: 4;

(2) color fastness to alkali perspiration (grade): color change: 4; staining: 4;

(3) color fastness to soaping (grade): color change: 3-4; staining: 3;

(4) color fastness to crocking (grade): dry crocking: 4; wet crocking: 3-4;

(5) color fastness to light (color change): 3;

(6) breaking strength (N): warp 778, weft 1030;

(7) elongation at break (%): warp 87, weft 54; and

(8) tear strength (N): warp 45, weft 48.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

[0021] The present invention will be further described below by specific embodiments. The present invention is not limited by the following embodiments.

Embodiment 1

[0022] The present invention provides a polyester superfine staple fiber fabric, comprising upper mesh cloth, a polyester superfine staple fiber non-woven fabric, and lower mesh cloth, which are arranged from top to bottom in sequence. Both the upper mesh cloth and the lower mesh cloth are made of high-strength FDY filaments with 2000 twists and 75D/48F. The polyester superfine staple fiber non-woven fabric is made of polyester superfine staple fibers having a denier per filament of 0.15 dtex.

[0023] The present invention provides a process for manufacturing a polyester superfine staple fiber fabric, comprising steps of:

(1) laying polyester superfine staple fibers having a denier per filament of 0.15 dtex as raw material, to form a polyester superfine staple fiber layer;

(2) double-sided ribbing the polyester superfine staple fiber layer with mesh cloth made of high-strength FDY filaments with 2000 twists and 75D/48F, and needling;

(3) ironing to form grey cloth;

(4) pre-shrinking the grey cloth in an impregnating tank at 90°C for 10 min;

(5) impregnating with water-soluble resin and then drying;

(6) impregnating with water-soluble polyurethane and then drying;

(7) splitting;

(8) wet sanding;

(9) rubbing: after wetting the cloth by water, transferring it into a drum device, wherein steam in the drum is at 85°C, the drum swings to and fro between positive 120° and negative 120° , and the drum device finishes the swinging action from the positive to negative direction or from the negative to positive direction within 20s;

(10) dyeing; and

(11) napping to obtain the finished product.

[0024] In the step (2), the needling is done at a speed of 2 m/min and at a frequency of 700 times per minute.

[0025] In the step (3), the ironing is done at a speed of 3 m/min and at a temperature of 140°C.

[0026] In the step (5), the water-soluble resin has a viscosity of 50 cps and a solid content of 15%, and a liquid content in the grey cloth is 80%; and the drying is done at a temperature of 125 °C and at a speed of 5 m/min.

[0027] In the step (6), the water-soluble polyurethane has a viscosity of 300 cps and a solid content of 40%, and a liquid content in the grey cloth is 150%; and the drying is done by three ovens, among which the first oven has a temperature of 110°C, the second oven has a temperature of 145°C, and the third oven has a temperature of 120°C, and at a speed of 3 m/min.

[0028] In the step (7), the splitting is done with NaOH having a concentration of 10 g/L, at a temperature of 85°C, for 90 min.

[0029] In the step (8), first wet sanding is done by two sand-rollers, both of which are 150 meshes; then, second wet sanding is done by one sand-roller which is 300 meshes; finally, third wet sanding is done by one sand-roller which is 400 meshes; and the wet sanding is done at a speed of 5 m/min and all the sand-rollers work at a speed of 1500 revolutions/min.

[0030] In the step (10), the dyeing is done with a disperse dye by a low-bath-ratio one-bath process, at a bath ratio of 1:8 and at a temperature of 120°C.

[0031] In the step (11), first napping is done by two sand-rollers, both of which are 240 meshes; then, second napping is done by two sand-rollers, both of which are 400 meshes; finally, carding is done by a carding roller; and the napping is done at a speed of 5 m/min and all the sand-rollers work at a speed of 1500 revolutions/min.

Embodiment 2

[0032] The present invention provides a polyester superfine staple fiber fabric, comprising upper mesh cloth, a polyester superfine staple fiber non-woven fabric, and lower mesh cloth, which are arranged from top to bottom in sequence. Both the upper mesh cloth and the lower mesh cloth are made of high-strength FDY filaments with 3000 twists and 90D/48F. The polyester superfine staple fiber non-woven fabric is made of polyester superfine staple fibers having a denier per filament of 0.2 dtex.

[0033] The present invention provides a process for manufacturing a polyester superfine staple fiber fabric, comprising steps of:

(1) laying polyester superfine staple fibers having a denier per filament of 0.2 dtex as raw material, to form a polyester superfine staple fiber layer;

(2) double-sided ribbing the polyester superfine staple fiber layer with mesh cloth made of high-strength FDY filaments with 3000 twists and 90D/48F, and needling;

(3) ironing to form grey cloth;

(4) pre-shrinking the grey cloth in an impregnating tank at 95°C for 8 min;

(5) impregnating with water-soluble resin and then drying;

(6) impregnating with water-soluble polyurethane and then drying;

(7) splitting;

(8) wet sanding;

(9) rubbing: after wetting the cloth by water, transferring it into a drum device, wherein steam in the drum is at 102°C, the drum swings to and fro between positive 120° and negative 120° , and the drum device finishes the swinging action from the positive to negative direction or from the negative to positive direction within 30s;

(10) dyeing; and

(11) napping to obtain the finished product.

[0034] In the step (2), the needling is done at a speed of 2.2 m/min and at a frequency of 700 times per minute.

[0035] In the step (3), the ironing is done at a speed of 3.5 m/min and at a temperature of 140°C.

[0036] In the step (5), the water-soluble resin has a viscosity of 0 cps and a solid content of 18%, and a liquid content in the grey cloth is 100%; and the drying is done at a temperature of 130°C and at a speed of 6 m/min.

[0037] In the step (6), the water-soluble polyurethane has a viscosity of 600 cps and a solid content of 45%, and a liquid content in the grey cloth is 160%; and the drying is done by three ovens, among which the first oven has a temperature of 118 °C, the second oven has a temperature of 150°C, and the third oven has a temperature of 125°C, and at a speed of 4 m/min.

[0038] In the step (7), the splitting is done with NaOH having a concentration of 20 g/L, at a temperature of 100°C, for 60 min.

[0039] In the step (8), first wet sanding is done by two sand-rollers, both of which are 220 meshes; then, second wet sanding is done by one sand-roller which is 350 meshes; finally, third wet sanding is done by one sand-roller which is 500 meshes; and the wet sanding is done at a speed of 8 m/min and all the sand-rollers work at a speed of 1800 revolutions/min.

[0040] In the step (10), the dyeing is done with a disperse dye by a low-bath-ratio one-bath process, at a bath ratio of 1:9 and at a temperature of 122°C.

[0041] In the step (11), first napping is done by two sand-rollers, both of which are 280 meshes; then, second napping is done by two sand-rollers, both of which are 500 meshes; finally, carding is done by a carding roller; and the napping is done at a speed of 6 m/min and all the sand-rollers work at a speed of 1800 revolutions/min.

Embodiment 3

[0042] The present invention provides a polyester superfine staple fiber fabric, comprising upper mesh cloth, a polyester superfine staple fiber non-woven fabric, and lower mesh cloth, which are arranged from top to bottom in sequence. Both the upper mesh cloth and the lower mesh cloth are made of high-strength FDY filaments with 4000 twists and 100D/48F. The polyester superfine staple fiber non-woven fabric is made of polyester superfine staple fibers having a denier per filament of 0.25 dtex.

[0043] The present invention provides a process for manufacturing a polyester superfine staple fiber fabric, comprising steps of:

(1) laying polyester superfine staple fibers having a denier per filament of 0.25 dtex as raw material, to form a polyester superfine staple fiber layer;

(2) double-sided ribbing the polyester superfine staple fiber layer with mesh cloth made of high-strength FDY filaments with 4000 twists and 100D/48F, and needling;

(3) ironing to form grey cloth;

(4) pre-shrinking the grey cloth in an impregnating tank at 100°C for 5 min;

(5) impregnating with water-soluble resin and then drying;

(6) impregnating with water-soluble polyurethane and then drying;

(7) splitting;

(8) wet sanding;

(9) rubbing: after wetting the cloth by water, transferring it into a drum device, wherein steam in the drum is at 110°C, the drum swings to and fro between positive 120° and negative 120° , and the drum device finishes the swinging action from the positive to negative direction or from the negative to positive direction within 40s;

(10) dyeing; and

(11) napping to obtain the finished product.

[0044] In the step (2), the needling is done at a speed of 2.5 m/min and at a frequency of 700 times per minute.

[0045] In the step (3), the ironing is done at a speed of 4 m/min and at a temperature of 140°C.

[0046] In the step (5), the water-soluble resin has a viscosity of 0 cps and a solid content of 20%, and a liquid content in the grey cloth is 120%; and the drying is done at a temperature of 135°C and at a speed of 7 m/min.

[0047] In the step (6), the water-soluble polyurethane has a viscosity of 1000 cps and a solid content of 50%, and a liquid content in the grey cloth is 180%; and the drying is done by three ovens, among which the first oven has a temperature of 125 °C, the second oven has a temperature of 160°C, and the third oven has a temperature of 130°C, and at a speed of 5 m/min.

[0048] In the step (7), the splitting is done with NaOH having a concentration of 30 g/L, at a temperature of 110°C, for 45 min.

[0049] In the step (8), first wet sanding is done by two sand-rollers, both of which are 300 meshes; then, second wet sanding is done by one sand-roller which is 400 meshes; finally, third wet sanding is done by one sand-roller which is 600 meshes; and the wet sanding is done at a speed of 10 m/min and all the sand-rollers work at a speed of 2100 revolutions/min.

[0050] In the step (10), the dyeing is done with a disperse dye by a low-bath-ratio one-bath process, at a bath ratio of 1:10 and at a temperature of 125°C.

[0051] In the step (11), first napping is done by two sand-rollers, both of which are 320 meshes; then, second napping is done by two sand-rollers, both of which are 600 meshes; finally, carding is done by a carding roller; and the napping is done at a speed of 8 m/min and all the sand-rollers work at a speed of 2100 revolutions/min.

[0052] In all the above embodiments, both the upper mesh cloth and the lower mesh cloth are made by plain weave organization. The high-strength FDY filaments have a strength of 6-7 g/d.

[0053] The above embodiments are merely used for explaining the inventive concepts of the present invention, not intended to define the protection scope of the present invention. All substantive changes to the present invention based on those concepts shall be included in the protection scope of the present invention.

Claims

1. A process for manufacturing a polyester superfine staple fiber fabric, comprising steps of:

(1) laying polyester superfine staple fibers having a denier per filament of 0.15-0.25 dtex as raw material, to form a polyester superfine staple fiber layer;

(2) double-sided ribbing the polyester superfine staple fiber layer with mesh cloth made of high-strength FDY filaments with 2000-4000 twists and 75-100D/48F, and needling;

(3) ironing to form grey cloth;

(4) pre-shrinking the grey cloth in an impregnating tank at 90-100°C for 5-10 min;

(5) impregnating with water-soluble resin and then drying;

(6) impregnating with water-soluble polyurethane and then drying;

(7) splitting;

(8) wet sanding;

(9) rubbing: after wetting the cloth by water, transferring it into a drum device, wherein steam in the drum is at 85-110°C, the drum swings to and fro between positive 120° and negative 120° , and the drum device finishes the whole swinging action from the positive to negative direction or from the negative to positive direction within 20s to 40s;

(10) dyeing; and

(11) napping to obtain the finished product.

2. The process for manufacturing a polyester superfine staple fiber fabric according to claim 1, wherein, in the step (2), the needling is done at a speed of 2-2.5 m/min and at a frequency of 600-800 times per minute.

3. The process for manufacturing a polyester superfine staple fiber fabric according to claim 1, wherein, in the step (3), the ironing is done at a speed of 3-4 m/min and at a temperature of 135-145 °C.

4. The process for manufacturing a polyester superfine staple fiber fabric according to claim 1, wherein, in the step (5), the water-soluble resin has a viscosity of 0-100cps and a solid content of 15-20%, and a liquid content in the grey cloth is 80-120%; and the drying is done at a temperature of 125-135 °C and at a speed of 5-7 m/min.

5. The process for manufacturing a polyester superfine staple fiber fabric according to claim 1, wherein, in the step (6), the water-soluble polyurethane has a viscosity of 300-1000 cps and a solid content of 40-50%, and a liquid content in the grey cloth is 150-180%; and the drying is done by three ovens, among which the first oven has a temperature of 110-125 °C, the second oven has a temperature of 145-160°C, and the third oven has a temperature of 120-130°C, and at a speed of 3-5 m/min.

6. The process for manufacturing a polyester superfine staple fiber fabric according to claim 1, wherein, in the step (7), the splitting is done with NaOH having a concentration of 10-30 g/L, at a temperature of 85-110°C, for 45-90 min.

7. The process for manufacturing a polyester superfine staple fiber fabric according to claim 1, wherein, in the step (8), first wet sanding is done by two sand-rollers, both of which are 150-300 meshes; then, second wet sanding is done by one sand-roller which is 300-400 meshes; finally, third wet sanding is done by one sand-roller which is 400-600 meshes; and the wet sanding is done at a speed of 5-10 m/min and all the sand-rollers work at a speed of 1500-2100 revolutions/min.

8. The process for manufacturing a polyester superfine staple fiber fabric according to claim 1, wherein, in the step (10), the dyeing is done with a disperse dye by a low-bath-ratio one-bath process, at a bath ratio of 1:8-1:10 and at a temperature of 120-125 °C.

9. The process for manufacturing a polyester superfine staple fiber fabric according to claim 1, wherein, in the napping step (11), first napping is done by two sand-rollers, both of which are 240-320 meshes; then, second napping is done by two sand-rollers, both of which are 400-600 meshes; finally, carding is done by a carding roller; and the napping is done at a speed of 5-8 m/min and all the sand-rollers work at a speed of 1500-2100 revolutions/min.

10. A polyester superfine staple fiber fabric, manufactured by the process according to claims 1-9, wherein the fabric comprises upper mesh cloth, a polyester superfine staple fiber non-woven fabric, and lower mesh cloth, which are arranged from top to bottom in sequence;
wherein both the upper mesh cloth and the lower mesh cloth are made of high-strength FDY filaments with 2000-4000 twists and 75-100D/48F; and
wherein the polyester superfine staple fiber non-woven fabric is made of polyester superfine staple fibers having a denier per filament of 0.15-0.25 dtex, and is double-sided ribbed with the upper mesh cloth and the lower mesh cloth and needled.

11. The polyester superfine staple fiber fabric according to claim 10, wherein the fabric is impregnated with water-soluble polyurethane.