Full analysis of six dimensions of Lenzing rayon regeneration, sand washing and air layer principle, process application and maintenance

Lenzing rayon recycled polyester sand-washed air layer is a three-layer functional environmentally friendly fabric made of Lenzing rayon fiber and regenerated polyester fiber as the core raw materials, double-sided weaving + sand-washing and finishing. It combines the moisture absorption and skin-friendly properties of Lenzing rayon, the stiff and wear-resistant texture of recycled polyester, and the soft and waxy texture of sand-washing. It is a high-end material for casual wear and home wear, and is in line with the development trend of green textiles. The following is a detailed explanation from six dimensions to provide reference for industry selection.

1. Principles: core mechanism of performance advantages

The properties of this fabric come from the triple effects of fiber synergy, air layer structure and sand washing process:

1. Synergistic mechanism of fiber ratio: Lenzing rayon (40%-50%) is a natural cellulose fiber with a moisture absorption rate of 13%-15%, which is skin-friendly, breathable and non-irritating; recycled polyester (50%-60%) is derived from recycled PET bottle flakes. Its molecular chain structure is stable, giving the fabric strong anti-wrinkle and dimensional stability. The blend of the two solves the pain points of pure cotton being prone to wrinkles and pure polyester being stuffy, achieving "both comfort and durability".

2. The functional principle of the air layer structure: the fabric adopts a three-layer structure of surface layer, bottom layer blended plain weave + middle hollow layer. The thickness of the air layer is 0.5-0.8mm. It uses the insulation and buffering properties of air to achieve "warmth without bulk"; the hollow layer accelerates air circulation, and cooperates with the hygroscopic properties of Lenzing rayon to quickly export sweat, making it suitable for wearing in many seasons.

3. Principle of sand washing process modification: Through physical or chemical sand washing treatment, the surface fibers of the fabric produce a micro-velvety feel, which reduces the rigidity of the fabric and improves the soft and waxy feel; at the same time, sand washing can eliminate internal stress in the weaving.Strength, the fabric shrinkage is controlled within 2%, and the dimensional stability is improved.

2. Technology: key processes of weaving and finishing

Fabric production is divided into three core links: raw material pretreatment - double-sided weaving - sand washing and finishing. Each step requires precise control of parameters:

1. Raw material pre-treatment: Lenzing rayon fiber is opened and impurity removed to improve the uniformity of spinning; recycled polyester slices are melt-spun into 75D/36F filament, which is blended with Lenzing rayon fiber in proportion to form yarn. The yarn count is 32S, taking into account strength and feel.

2. Double-sided weaving process

• A high-speed double-sided warp knitting machine is used, equipped with three bars. Bars 1 and 3 weave the blended yarn of the surface layer and the bottom layer, and bar 2 weaves the connecting yarn to form a hollow air layer;

• When weaving, the stitch length is 28G-32G, the warp tension is controlled at 10-15cN, and the fabric weight is controlled at 220-300g/㎡ to ensure uniform air layer thickness and no delamination defects.

3. Finishing process after sand washing: first pre-shape at 140-150°C, and then use pumice sand washing process (pumice particle size 0.5-1mm, liquor ratio 1:15, temperature 40-50°C, time 30-40min) to form a uniform velvet feel on the surface of the fabric; after sand washing, perform soft finishing and low-temperature setting (temperature ≤ 130°C) to avoid high temperature damage to fiber properties.

3. Application Category: Accurate adaptation to multi-domain scenarios

With its environmentally friendly properties and comfortable texture, this fabric covers multiple segments of the clothing industry:

1. Casual clothing field: used to make sweatshirts, hoodies, shirts and jackets. The sand-washed soft and waxy feel enhances the wearing experience. The air layer's warmth is suitable for spring and autumn wear. The environmental protection attributes are in line with the brand's green development concept;

2. Home apparel field: produces pajamas, pajamas, and home suits. The skin-friendly properties of Lenzing rayon fit the human skin and are non-irritating, making it suitable for long-term home wear;

3. Children's clothing field: making children's sweatshirts and jackets, which are soft and odorless, comply with children's clothing safety standards, and are wear-resistant and washable to adapt to the lively and active characteristics of children;

4. Light outdoor field: used for lightweight outdoor jacket lining, keeping warm and breathable while taking into account lightweight requirements. The wear-resistant properties of recycled polyester extend the service life of the fabric.

4. Maintenance: Fabric storage and cleaning skills

1. Fabric storage and maintenance

• Storage environment: Place in a cool and dry warehouse with a temperature of 15-30°C and a relative humidity of less than 60%. Avoid direct sunlight to prevent the yellowing of Lenzing rayon and the aging of recycled polyester;

• Stacking requirements: Store rolled fabrics vertically to avoid collapse of the air layer caused by heavy pressure; store fabrics of different colors in separate seals to prevent dye migration; keep away from acids, alkalis, and organic solvents to avoid fiber damage.

2. Finished product care and maintenance

• Washing method: Use neutral detergent, hand wash in cold water or gentle machine wash (put in a laundry bag), avoid vigorous rubbing to prevent the sand washing pile layer from falling off and air layer delamination; it is forbidden to use bleach and chlorine-containing detergents to avoid damaging the fiber structure;

• Drying and ironing: Lay flat to dry in a cool and ventilated place, prohibit exposure to the sun; if ironing is required, control the temperature at 100-120°C and iron at low temperature with a pad to avoid direct ironing that may damage the velvet feel;

• Special attention: avoid friction with sharp objects when wearing to prevent snagging; the fabric has been sand washed to avoid long-term soaking and reduce wear of the pile layer.

5. Technology: the core direction of performance upgrades

Fabric technology innovation focuses on two major sectors: fiber modification and process optimization:

1. Functional modification technology: Develop antibacterial fabrics (added with plant antibacterial agents), with an antibacterial rate of over 99%, suitable for close-fitting clothing scenarios; introduce anti-UV additives to increase the UPF value of the fabric to 50+, and expand the application of outdoor clothing;

2. Process optimization direction: Use fine-denier recycled polyester fiber (40D/12F) blending to improve the fineness of the fabric; develop differentiated sand washing processes to customize fabrics with different feel such as "light velvet feel" and "heavy velvet feel"; optimize the weaving process and control the air layer thickness tolerance to ±0.05mm to improve product consistency;

3. Environmentally friendly process upgrade: Promote low-temperature dyeing technology (dying temperature ≤95°C) to reduce energy consumption and wastewater emissions; use waterless digital printing technology to replace traditional dyeing processes and reduce environmental pollution.

6. Trend Category: The future direction of industry development

As the textile industry transforms towards "green, functional and personalized", this fabric is showing three major development trends:

1. The deepening trend of greening: the proportion of recycled polyester raw materials has been increased to more than 80%, and blockchain technology has been introduced to realize raw material traceability to meet brand environmental certification and consumer traceability needs;

2. The trend of functional compounding: from a single function of warmth and comfort to a multi-functional compound direction of "warmth + antibacterial + anti-UV + moisture absorption and heating" to adapt to the clothing needs of multiple scenes;

3. Customization trend: In response to the needs of clothing brands, we provide personalized customization services in terms of hand feeling, air layer thickness, and weight, and develop sub-categories such as ultra-thin models (weight <200g/㎡) and thickened models (weight>350g/㎡).