Method for boiling-off of blended fabric from polyamide fiber and polyurethane fiber, method for producing dyed blended fabric and dyed blended fabric

Abstract

A method for scouring a mixed fabric of polyamide fibers and polyurethane fibers is provided, wherein soft water as treating water is used and the treating water contains a sequestering agent. According to the present invention, a mixed fabric of polyamide fibers and polyurethane fibers in which uneven dyeing hardly arises, that is, excellent leveling is achieved, is provided.

Description

[0001] TECHNICAL FIELD[0002] The present invention relates to a method for scouring mixed fabrics of polyamide fibers and polyurethane fibers, a method for manufacturing dyed mixed fabrics, and dyed mixed fabrics.[0003] The present invention more particularly relates to a method for scouring a mixed fabric of polyamide fibers and polyurethane fibers, a method for manufacturing a dyed mixed fabric, and a dyed mixed fabric, in which the mixed fabric is effectively scoured by removing stains or oil smears and is excellent in leveling.[0004] BACKGROUND ART[0005] Polyurethane fibers are used for many kinds of wear such as innerwear, pantyhose, swimming wear, leotards, and outerwear because of their excellent characteristics such as stretching properties, shape retention, fitting properties, formability, unique texture, and crease resistance.[0006] Since pliable and soft texture is necessary for wear such as innerwear, pantyhose, swimming wear, leotards, and outerwear, which are in contac...

AI Technical Summary

Benefits of technology

[0032] Since a continuous process in which fabrics are continuously fed into treating water is more efficient than a batch process in which the treating water is discarded after each operation, the mixed fabric according to the present invention is preferably scoured by the continuous process.

[0037] In a scouring treatment according to the present invention, soft water is preferably used as the treating water. When using hard water containing metal ions such as calcium and magnesium ions, the following disadvantages may arise: a lowering of efficiency, and the uneven dyeing and a lowering of dyeing property due to the formation of complexes composed of metal ions and acid dyes. The concentration of metal ions in the water, which indicates total hardness, is preferably 40 ppm or less, and more preferably 30 ppm or less.

[0041] According to the present invention, the sequestering agent is preferably added in at least the initial step of the scouring treatment in order to improve the scouring effect by causing the mixed fabric to be in contact with the treating water for a suitably long time. For example, when using the above continuous scouring apparatus having the plurality of tanks, the sequestering agent is preferably fed into at least the first tank in which the mixed fabric is first treated.

[0043] The treating water preferably further contains polyphosphoric acid functioning as a dispersant in order to improve the dispersion of metal chelates, to prevent the metal chelates from adhering to the mixed fabric, and to prevent the metal chelates from precipitating.

[0049] According to the present invention, the occurrence of dyeing specks and stains due to oil smears containing metals is prevented.

Problems solved by technology

There is a problem in that oil is apt to adhere to materials including polyurethane fibers.

Smears on knitting due to oil used in knitting machines have been increasing due to the diversity of mix materials, the complexity of knitting structure, and high-speed knitting operation.

Furthermore, the removal of oil in a scouring step is difficult due to contamination of metals in the oil, such as iron or copper used for lube oil pipes for knitting machines or knitting machine needles.

Thus, in the dyeing process of mixed fabrics of polyamide fibers and polyurethane fibers, when contaminants such as oil smears are not thoroughly removed in a scouring step before a dyeing step, product deficiency such as dyeing specks or oil smears arises.

However, since oil smears are not sufficiently removed in a scouring step by such a method, problems due to dyeing specks or oil smears have arisen.

The above method is excellent in removing oil but is not substantially effective in the removal of smears containing metals and in the prevention of oil smears.

However, such methods have small effects and cause a decrease of color fastness in some cases.

When the content is less than 25% by weight, spinning is apt to be difficult due to the increasing heat required to vaporize the solvent.

On the other hand, when the content exceeds 80% by weight, spinning is also apt to be difficult due to a decline in the stability of the solvent.

When using hard water containing metal ions such as calcium and magnesium ions, the following disadvantages may arise: a lowering of efficiency, and the uneven dyeing and a lowering of dyeing property due to the formation of complexes composed of metal ions and acid dyes.