What is the information corresponding to the specification, weight, density and type of denim?

Since the late 1970s, denim has experienced many great developments in China. At present, the annual production capacity is expected to exceed 654.38+0.5 billion square meters, and it has become an important producer of denim in the world. A large number of advanced denim and denim garment enterprises have basically reached international standards in quality and variety, which has initially reversed the concept that China denim products belong to "low-grade products" in the international market. Although the development and production of cowboy products in China started late, it started at a high level, with advanced equipment such as air spinning, automatic winding, warp dyeing, shuttleless loom (rapier, gripper and air jet) and heavy-duty pre-shrinking finishing machine, which created good conditions for the development of cowboy varieties and the improvement of quality level. However, for a long time, some equipment with excellent performance and complete functions, such as electronic multi-arm, multi-color, uneven winding, rapid variety change and unmanned operation, have not attracted enough attention, resulting in a waste of functions. In order to better serve variety development and improve quality and labor productivity, this situation needs to be solved urgently. At present, the most popular denim varieties at home and abroad are mainly ring spinning denim, warp and weft slub denim, super indigo dyed denim, color matching denim, color matching denim, weft elastic denim and so on. With the development and application of new technologies and equipment such as ring spinning with high speed, large package, fine winding and no knot, the shortcomings of short spinning length, low production efficiency and many knots of coarse count yarn have been solved. The situation that denim yarn is replaced by air-spun yarn is changing rapidly, and ring-spun yarn is likely to make a comeback. Because ring spinning denim is superior to air spinning denim in some properties, such as hand feeling, drape, tear strength and so on. Moreover, it is also influenced by people's psychological return to nature and the pursuit of the original development of cowboy style. More importantly, the surface of ring spinning jeans will show a hazy slub style after grinding and washing, which meets the individual needs of today's jeans. In addition, slub yarn denim is very popular in the market at present, and ring spinning slubs can spin shorter and denser slubs, which also promotes the development momentum of ring spinning denim. When slub denim is designed with slub yarns with different yarn numbers, different slub thicknesses (compared with base yarns), different slub lengths and pitches, and slub yarns in single warp direction, single weft direction and warp and weft direction are properly arranged with ordinary yarns with the same number or different numbers, various slub denim can be produced, and various hazy or clear striped denim can be formed after washing, which is favored by personalized consumer demand groups. In the early days, almost all slub denim used ring spinning slub yarn. Because it can be spun into slub yarn with short length, small pitch and relatively high density, it is easy to form dense embellishment effect on the cloth surface, mainly in the warp direction. With the development of market demand, warp and weft two-way slub denim is very popular at present, especially the two-way slub denim products with weft elasticity are very popular in domestic and foreign markets. However, as long as the weave structure of some varieties is well designed, a single variety of ring-spun yarn can be used in the warp direction and a proper proportion of slub yarn in the weft direction, and the effect of warp and weft two-way slub cowboy can also be achieved. Weft elastic denim uses spandex elastic yarn, which makes denim varieties develop into a new field, and makes denim clothing close-fitting and comfortable. With slubs or different colors, denim products can adapt to fashionable and personalized consumption needs, so they have great development potential. At present, elastic denim is mostly weft elastic, and the elastic elongation is generally 20% ~ 40%. Elastic elongation depends on the weave design of the fabric. The smaller the warp and weft tightness on the loom, the greater the elasticity. On the other hand, under the condition of fixed warp knitting tightness, the greater the tightness of weft elastic yarn, the smaller the elasticity, and the weft tightness will reach a certain level or even lose elasticity. In addition, the outstanding problem of the finished fabric of elastic denim is that the weft shrinkage is too large, generally above 10%, and even as high as 20% in some cases. The instability of cloth width has brought great difficulties to garment production. The first solution is not to make the elastic stretch too large when designing products, generally taking 20% ~ 30%, that is, to maintain a certain degree of warp and weft tightness, and to increase the tension appropriately during pre-shrinkage, so as to make the cloth width shrink greatly, so as to obtain a lower residual shrinkage rate in the weft direction of the finished cloth; Another solution is to heat-set the pre-shrunk elastic denim to obtain a more uniform cloth width, a more stable and lower weft shrinkage rate, and meet the requirements of garment processing and production. Denim with special colors is widely welcomed by consumers, because clothes made of super indigo dyed or super deep indigo dyed denim can get rich and bright colors after grinding and washing. "Super indigo" dyed denim has two characteristics: extremely deep dyeing depth and excellent color fastness to rubbing and washing. The former means that the amount of indigo dye dyed on yarn per unit weight (generally expressed as% of yarn dry weight and% of dyeing depth) is very large. For example, the dyeing depth of conventional denim warp is 1% ~ 3%, while the dyeing depth of "super indigo" needs to reach more than 4% to be called super indigo or super deep indigo. The latter means that "super indigo" dyed jeans need to be washed repeatedly for more than 3 hours, and their color depth can still reach or exceed that of conventional dyed jeans without washing, and their color light is much brighter than that of conventional dyed jeans. For indigo dyed denim, its essence depends on the penetration degree of the dye into the yarn, not the abrasion fastness of the dye itself (the wet abrasion fastness of indigo is only 1), that is, the better the penetration degree, the better the abrasion fastness. In the past, the so-called "indigo dyeing rapid washing process" actually made indigo dye penetrate into the core of the fiber very shallowly during the yarn dyeing process, so that when denim clothing was ground and washed, a thin layer of dye on the yarn surface was removed, exposing more white yarn cores, which made the color fade quickly, thus achieving the effect of fading immediately after short-time grinding and washing. However, the dyeing process of "Super Indigo" is the opposite, which requires the dye to penetrate into the core well, so that the denim clothing can get deep and bright colors after sanding and washing. Because the dyeing depth of "super indigo" dyed denim products is more than 60% higher than that of conventional denim dyeing, the indigo concentration of the dyeing solution will also double, even reaching 3 ~ 4g/L, and it is possible to obtain a deeper color. In this way, the viscosity of dye solution increases, the fluidity becomes worse, the permeability of dye leuco is affected, and the color fastness of denim decreases, which can not meet the demand of final depth in clothing production. Therefore, some enterprises adopt the design of increasing the dyeing depth again, so that the indigo concentration in the dyeing solution increases again and the permeability becomes worse, thus forming a vicious circle, and still can not meet the requirements of "super indigo" color. The higher the concentration of indigo in dye solution, the heavier the red light and the darker the color, and there is no "super indigo" effect. Therefore, at present, many factories have or are going to reform the dyeing and sizing equipment and solve this problem by increasing dyeing passes. For example, if the number of dyeing passes is increased to 8 or even 10, it will not only increase the investment cost and the consumption of dyeing materials, but also increase the difficulty of operation and increase the pollution to the environment. A better way to solve this problem is to appropriately reduce the dosage of sodium hydrosulfite or caustic soda, especially to control the dosage of caustic soda, so that the PH value of the dye solution is stable between 1 1 ~ 12, the dye uptake is the highest, the color is stable, and at the same time, the dyeing tension of warp yarn is appropriately reduced to obtain a better "super indigo" dyeing effect. In order to increase the color and tone change of indigo denim, various indigo denim varieties are very popular at present. For example, indigo dye black sulfide, indigo dye grass green sulfide, black green sulfide, blue sulfide and so on. To meet the individual needs of the market. At the same time, denim manufacturers have their own new varieties of denim and patented special colors to improve market competitiveness. In this regard, attention should be paid to controlling the concentration of mother liquor as much as possible to prevent excessive overflow of dye liquor from causing dye waste and expanding environmental pollution. Colored (assorted) denim mainly includes indigo blue denim and black sulfide denim, as well as coffee, turquoise, gray, khaki and blue sulfide denim dyed with sulfide dyes, and a small amount of red, pink and princess denim dyed with Nafto dyes or reactive dyes. Although the production batch is not large, the market demand is urgent and often cannot meet the needs. The main problem is that the color light is not stable enough, the dyeing attention is poor, and the clothing manufacturers are not satisfied. This is of course related to the small production batch and too many colors, but it is difficult, costly and difficult to treat sewage by printing and dyeing sizing machine. The first solution is to minimize the number of color combinations, try to use two color combinations, no more than three color combinations, or replace them with other stable dye varieties to adapt to the production characteristics of dyeing machines and obtain stable dyeing effects; Secondly, the more thorough solution is to use the production process of dyeing yarn in large-capacity yarn-dyed factories and warping with different stripes to produce denim with different colors. Denim is made of pure cotton indigo dyed warp yarns and natural weft yarns, which are interwoven with a twill weave with three tops and one bottom. Generally, it can be divided into light and medium denim. Moreover, the weight of heavy three kinds of light cloth is 200-340g/ m2 (6- 10oz/ square yard), the weight of medium-sized cloth is 340-450g/ m2 (10- 13oz/ square yard), the weight of heavy cloth is more than 450g, and the yarn count is thick. Heavy 7×6, medium 10× 10, light 12× 12 (British Division). The width of cloth is mostly between 1 14- 152 cm. In addition to the above traditional products, there are colors. 1. Denim with different raw material structures; (1) Elastic denim woven with a small proportion of spandex yarn (about 3-4% of the yarn weight) as the elastic warp or weft of the core-spun yarn. (2) Snowflake denim takes low proportion polyester blended cotton as warp yarn, which produces blank effect after dyeing. (3) High-grade denim woven from cotton, linen and cotton wool blended yarn. (4) Denim woven with medium-long fibers (T/R). 2. Denim woven by different processing technologies. (1) Bark Crepe Denim Woven with High Twist Weft. (2) When the warp is dyed, it should be dyed with sulfide or Haichanglan first, and then dyed with indigo. (3) Indigo covered dyed denim