JPS6157432B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a fiber sheet having napped fibers made of ultrafine fibers with excellent napped properties and texture. In other words, the present invention relates to a method of applying a polymeric substance to a fiber sheet-like material having napped fibers made of ultrafine fibers by being raised in advance, the sheet-like material having excellent napped properties and texture. The purpose is to obtain the following properties and to further enhance the processing effect of adding a polymeric substance.

Conventionally, the idea of adding a polymeric substance to a fiber sheet to improve its texture, resilience, and wrinkle resistance has been known. On the other hand, it is known that simply adding an elastic polymeric substance to a fiber sheet-like material such as a nonwoven fabric or a woven fabric cannot produce a product of good quality, and many improvement methods have been attempted.

In particular, simply applying an emulsion of a polymeric substance to a sheet and drying it normally will not yield good results as the polymer resin will concentrate on the surface area due to severe migration as the emulsion dries. I can't.

For this reason, it is possible to consider using a glue, but normal glue dissolves in water and is difficult to effectively achieve its purpose. On the other hand, a method has been considered in which a migration inhibitor is added to an emulsion of a polymeric substance. This is certainly effective. However, even this method cannot sufficiently prevent migration. The effect is insufficient. In order to make the anti-migration agent more effective, adding a large amount of the agent may cause gelation,
This causes coarsening of particles, uneven impregnation, reduction in particle coagulation and solidification (after drying), gum up, resulting uneven dyeing, and spot-like product defects. A means to solve this problem has been sought for a long time, but it has not yet been achieved.

It is an object of the present invention to provide an effective method to compensate for such conventional deficiencies.

The outline is as follows.

(1) In a method of applying an emulsion of a polymer substance to a fiber sheet-like material having napped fibers made of ultrafine fibers that have been previously napped and heating and drying the napped side to regrow the napped side, the opposite side of the napped side is A method for producing a fibrous sheet with excellent napping properties and texture, which comprises drying under hot air blowing conditions for stronger drying, and then subjecting the opposite side to a re-pilling treatment.

The present invention will be explained in detail below.

Normally, a pin tenter, clip tenter, floater dryer, etc. are used to dry the fiber sheet, and all of them involve blowing hot air from above and below. High frequency drying is still not a common sheet drying method in terms of longevity and energy costs.

These hot air methods rely on steam heaters, gas flames, or electric heaters; for example, a heat exchanger attached to the machine is installed right next to the seat, and the hot air is ducted from the exchanger above and below the seat. , sprayed from the slit nozzle just enough to float. Therefore, the sheet is dried extremely efficiently.

In contrast, in the present invention, hot air is blown only from one direction, either upward or downward.

From the opposite direction, either stop blowing or only blow cold air. To stop spraying, there are methods such as stopping the blowing fan, attaching a shield to the blowing outlet, moving or inserting another shielding sheet along with the sheet. Blowing only cold air means blowing only unheated air with a fan, or conversely blowing cooled air.

The method according to the present invention is a method that cannot be considered in the industry because the drying ability is significantly reduced compared to the past. It is extremely effective in obtaining the following, and because of the magnitude of the effect, the above-mentioned points do not limit the effectiveness of the present invention in any way.

Furthermore, the effectiveness of the present invention will be explained by taking an example.

For example, by applying a polyurethane emulsion to a napped fabric made of ultra-fine fibers,
When making a suede-like material with excellent physical properties, it is difficult to obtain a good product by simply applying a polyurethane emulsion to a previously raised woven or knitted material.

If a high concentration is applied and processed, the raised piloe will be fixed with polyurethane and will not be good, and even if buffed to dig out the raised piloe, not only will it not be possible to dig out the piloe well, but the raised piloe and the raised piloe will not be properly removed. An excessively sticky polyurethane resin can be seen between the layers, resulting in an "irritable" appearance, and this, together with the fact that the fluff does not stand up well, significantly reduces the product value.

On the other hand, when processed at a low concentration, the effects themselves, such as the effect of improving texture and improving physical properties (e.g. wrinkle recovery, resilience, anti-slip effect, various strengths, etc.), are too small, and it takes a little more time. However, there was a problem in that the concentration could not be increased and the intended purpose could not be achieved due to the above-mentioned reasons.

The present invention successfully solves this problem.
Moisture does not evaporate from the side of the ultra-fine fibers that should be the raised side, where strong migration is a problem, but evaporates from the other side, resulting in excellent hair raising properties, improved irritation, and an extremely smooth texture. It was discovered that an excellent napped fiber sheet could be obtained.
This has led to the present invention. For example, when the surface is covered with ultra-fine fibers, and the back side is a surface with a significant exposure probability of thick fibers, due to capillary action, the surface is covered with more In order to prevent a large amount of resin from sticking to the napped (ultra-fine) surface (which contains liquid and has a tendency to permeate), it is necessary to suppress the evaporation of moisture from that surface and evaporate from the other surface. It is. This is a method that has not been noticed until now, and for this purpose, hot air is applied more strongly to other surfaces to promote evaporation, while suppressing evaporation from the ultra-fine napped surface.

In this way, in order to prevent a large amount of resin from adhering to the napped surface and to cause migration in the thickness direction of the resin so that more resin adheres to the non-napped surface, the heating means is Radiation from a heater is not sufficient to heat from one side, so it is important to blow hot air from one side as described above.

In addition to this, it is also effective to use a migration inhibitor to prevent the resin from migrating to the surface of the ultrafine fiber that should be the raised surface. After drying with hot air, the ultra-fine fibers that have fallen down due to resin adhesion are raised again by buffing, combing effect, raking effect, brushing, etc.
The object of the present invention has been achieved, and an elegant raised sheet with good texture and touch can be obtained.

The emulsions used in the present invention are not limited to emulsions of elastic polymeric substances, but also emulsions of other resins, organic and inorganic substance emulsions,
This extends to colloids.

The present invention is particularly effective in processing elastic polymeric materials using emulsions. Examples include emulsions of many elastic polymeric substances, such as polyurethane emulsions, polyurea emulsions, and polyacrylic emulsions.

In the present invention, the fibrous sheet material includes various nonwoven fabrics such as woven fabrics, knitted fabrics, and needle-punched nonwoven fabrics, and is not particularly limited.

The means for forming napped on these sheet-like materials is not particularly limited, and all napped means such as looping, cutting, buffing, raising, etc. can be used. For example, all raised products such as buff-raised products, velvet, platen, velveteen, and kohl-ten are effective in the present invention.

What is effective in the present invention is one having napped fibers made of ultrafine fibers with a fineness of about 1 denier or less, particularly 0.2 denier or less. This is because the nape is weak and tends to fall down, and a large amount of liquid is likely to be contained in the fallen part due to capillary action or is likely to be diffused.
In this case, it goes without saying that when hot air is applied from above, the napped side of the ultrafine fibers should be placed downward, and when vice versa, the napped side should be placed upwards.

It should be noted that the surface to be exposed can be changed as appropriate depending on the purpose, and it goes without saying that intentionally changing the surface to which hot air is applied does not circumvent the present invention.

Next, examples related to the present invention will be shown, but the effectiveness of the present invention is not limited or constrained by these in any way, but rather the following applications, developments, etc.
It brings about development.

Example 1 As the warp yarn, polyethylene terephthalate (trade name "Tetron") 150 denier 48 filament, woolly yarn was used, and as the weft yarn, polymer array fiber with an island component of polyethylene terephthalate, island component ratio of 55%, seaweed A staple with a polystyrene-based polymer, sea component ratio of 45%, number of islands: 16, fineness of 3 denier, fiber length: 51 mm, number of crimps: 12 threads/in was used as the 20th twin spun yarn.

These were used as warp yarns and weft yarns, respectively, and the weaving structure was a 5-ply satin weave fabric with a weaving density of 100 warp yarns/in and 60 weft yarns/in.

When this fabric was introduced into boiling water and subjected to de-sizing and relaxation treatment during warp warping, it shrunk by about 13.9% in the weft direction, 11.7% in the warp direction, and 24.0% in area shrinkage.

This product was thoroughly washed five times with trichlorethylene to remove sea components.

This was passed through a French-type napping machine 22 times for a napping process, resulting in an ultra-fine nap fabric with a good nap texture that was hardly noticeable.

This raised fabric was impregnated with a polyether-based polyurethane emulsion having a concentration of 7% by weight, and then passed through a Nipprol mangle to squeeze the liquid to a squeezing rate of 125%.

In this dryer, the blower fan of the lower nozzle of the pin tenter dryer, which is normally used for drying sheet-like materials and heat setting, is turned off, and a cutting board is attached to the lower nozzle so that hot air is emitted from the lower nozzle. The impregnated and squeezed raised fabric was dried with the raised side (surface) facing down in a pin tenter dryer. The drying temperature was 100-110°C.

After drying, the emulsion polyurethane was cured by heat setting at 160-180°C.

This item has a lot of resin attached to the back side,
Only a small amount of resin was attached to the surface.

Next, the surface of this raised fabric was rubbed with 180 to 200 mesh sandpaper to remove a small amount of resin adhering to the surface, resulting in a soft-touch raised fabric with uniform raised surface.

Then, it was dyed brown using a disperse dye using a circular pressure dyeing machine, and dried after applying a finishing oil.

This product has a soft touch that tends to cause tie-yoke marks, and has a high nap density covered with ultra-fine fibers, so there is no noticeable weave or misalignment, and it has a well-balanced vertical and horizontal texture, and is resistant to wrinkles. A suede-like high-quality brushed fabric was obtained.

For comparison, when a polyurethane emulsion impregnated and squeezed was dried in a conventional double-sided hot air pin tenter dryer, a large amount of resin adhered to both the front and back sides, and the surface touch and the entire fabric were rough and hard. It became something of poor quality. In particular, the surface had no naps, had a rough touch, and was too rough and hard to be suede-like.

Example 2 As an impregnating liquid, 0.5% of methyl cellulose was added to a 10% concentration of polyether-based polyurethane emulsion.
The same processing as in Example 1 was carried out except for impregnating the material with the addition of %. Despite the high resin content, the surface was soft to the touch as in Example 1, and the surface was easily prone to yoke marks, with a well-balanced vertical and horizontal texture.
Although it is a woven fabric, a suede-like, highly brushed fabric with no noticeable weave was obtained.

Example 3 A polyacrylic emulsion with a concentration of 9% by weight was used as an impregnating liquid, and an acrylamide migration inhibitor ("Migress SH-2" manufactured by Meisei Chemical Industry Co., Ltd.) was used as an additive to prevent dye migration. The same process as in Example 1 was carried out except that the material was impregnated with 1.0% by weight of the anti-migration agent for polyurethane emulsion, polyacrylic emulsion, etc. After squeezing out the impregnating liquid (squeezing ratio: 120%), one-sided drying was performed using a pin tenter dryer with only hot air blowing from above, with the raised side facing down.

The fabric was then puffed, dyed, and finished in the same manner as in Example 1 to obtain a suede-like high-quality brushed fabric with a soft touch surface, uniformly raised and glossy texture, and a well-balanced vertical and horizontal texture.

Claims (1)

[Claims] 1. In a method of applying an emulsion of a polymer substance to a fiber sheet-like material having napped parts made of ultrafine fibers that have been previously napped and heating and drying the napped side to regrow the napped side, the opposite side of the side to be renapped is made stronger. A method for producing a fibrous sheet material having excellent napping properties and texture, which comprises drying under hot air blowing conditions, and then subjecting the opposite side to a re-pilling treatment.