The selection of spandex stretch yarn has expanded the denim variety to a new field, resulting in the birth of stretch denim and stretch jeans. Elastic denim can make denim clothing both snug and comfortable, and with bamboo knots or different colors, make denim products more fashionable and personalized consumer demand, so it has great development potential.

Elastic denim is a relatively new variety. The purpose of choosing elastic denim as jeans is to better express the beauty of human body lines. So how can we make full use of the advantages of elastic denim in terms of production technology and sewing technology, so as to produce high-quality elastic jeans? Let's start with the characteristics of stretch denim and stretch jeans:

1. Features of elastic denim:

The primary ingredient of elastic denim is elastic silk. Elastomeric fiber is a combination of polyurethane polymers. It can stretch five to six times after being pulled. After the position force disappears, it can return to its original state. Even if repeated repeatedly, the elasticity will not disappear. Elastic denim can be divided into three types: weft elasticity, warp elasticity and warp and weft elasticity, and the most commonly used is weft elastic denim. The weaving process of weft elastic denim is basically the same as that of ordinary denim, that is, the manufacturing process is: sizing and dyeing process - weaving - cleaning - shrinkage. The organizational structure of elastic denim is mostly the twill weave of the warp float. During weaving, the elastic weft should be extended as far as possible, so that the elasticity of the finished fabric will occur after the weft shrinkage. Compared with ordinary denim, the shrinkage of elastic denim is particularly large: the shrinkage in the straight direction is between 2% and 4%, while the shrinkage in the horizontal direction is between 16% and 22%. The large difference in the shrinkage between the two is the most important characteristic of elastic denim.

At present, elastic denim is mostly weft elastic. The elastic stretch is generally 20%~40%. The size of the elastic stretch depends on the fabric's organization planning. The smaller the warp and weft weave tightness on the loom, the greater the elasticity. On the contrary, under the condition of fixed warp weave tightness, the greater the weft elastic yarn tightness, the smaller the elasticity. The weft tension reaches a certain degree, and even the loss of elasticity will occur. In addition, the outstanding problem of elastic denim fabric is that the weft shrinkage is too large, generally more than 10%, and even more than 20%. Unstable cloth width brings great difficulties to clothing production. The first way to deal with it is not to make the elastic stretch too large during product planning, generally taking 20%~30%, that is, adhere to a certain degree of warp and weft organization tightness, and adopt the method of appropriately increasing the tension during pre-shrinking, so that the cloth width can be greatly shortened, so as to obtain a lower residual shrinkage rate in the weft direction of the product cloth; Another treatment method is to heat set the elastic denim after pre-shrinking, so as to obtain a more uniform cloth width and a more stable and lower weft shrinkage rate, satisfying the requirements of garment processing and production.

2. Features of elastic jeans should be paid attention to in pattern planning.

Because the shrinkage of elastic denim varies greatly between the vertical and horizontal directions, it is necessary to carefully test the accurate shrinkage before making the pattern. Scale cut pattern. In terms of style planning, it is best to choose the traditional five-bag style, that is, the front bag is a front curved bag with a clear watch bag; The back pocket is a three-pointed exposed patch bag. It should be avoided to select the seam bag with oblique and straight front pockets as far as possible, because the horizontal shrinkage of the fabric is large, and the pocket mouth is easy to deform after completion, which is difficult to control in production. In the pattern planning, some parts of jeans need to increase the width, such as the three-pointed open patch bag, which is cut according to the convention and sewed with ordinary denim. The shape before and after washing will not be too deformed, and sewed with elastic denim. The shape of the bag before washing is very regular, but after washing, the shape of the bag may become a shape with two ends folded inward. When making the pattern, The width of the back bag should be widened appropriately.

The article originated from denim millhttp://www.in-it.com.cn