High-performance thermal radiation insulation and fire-proof aluminum foil laminated fabrics are classified according to chemical structure
High-performance thermal radiation insulation, fire-proof aluminum foil laminated fabric Classified by chemical structure
1. Polyacrylate (PA):
Also called ac glue coating, it is the most common and common coating at present. After coating, it can increase the hand feel, windproof and drape.
PA white glue coating, that is, coating a layer of white acrylic resin on the surface of the fabric, can increase the covering rate of the cloth surface, make it opaque and make the color of the cloth surface more vivid.
PA silver glue coating is to apply a layer of silver-white glue on the surface of the fabric to make the fabric have light-shielding and radiation-proof functions. It is generally used in curtains, tents, and clothing.
PA coating, polyacrylate fabric coating glue (Polyacrylate abbreviated as PA), also called AC glue coating, that is, acrylic coating, is the most common and common coating at present. After coating, it can increase the hand feel, windproof, and There is a drapey feel. Commonly used for anti-velvet, hand feel, color and sand fixation, etc. There are also acrylic and pony glue, which are solvent-based acrylic coatings, suitable for water pressure-resistant coatings, and the price is slightly higher than AC. The original polyacrylate coating glue was a purely waterproof product. After decades of development, the current varieties not only have waterproof, moisture-permeable, flame-retardant and other functions, but also have low-temperature and energy-saving features. Polyacrylate coating glue is generally copolymerized by hard components (such as polymethyl acrylate, etc.) and soft components (such as polybutyl acrylate, etc.). The main monomers of polyacrylate coating include acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, etc. In order to improve its waterproof performance, acrylamide and acrylonitrile can be added when necessary. The polymerization initiator generally uses peroxide ( Such as potassium persulfate, etc.).
Waterproof coating finishing agent
This kind of polyacrylate coating finishing agent is initially a solvent-based product with excellent adhesion and water resistance. In order to improve the strength of the membrane, external bonding agents are often added. It is suitable for processing soft thin fabrics, and can achieve high water repellency and water pressure resistance by using it once. However, solvent-based products contain a large amount of organic solvents such as toluene, ethyl acetate, etc., which may easily cause environmental pollution or fire when used, and the cost of solvent recycling is high. There are two main methods for synthesizing solvent-based coating finishing agents. One is suspension polymerization, and the molecular weight of the resulting product is higher; the other is solution polymerization, and the molecular weight of the resulting product is low.
In order to overcome the shortcomings of solvent-based products, water-based polyacrylate coating finishing agents emerged at the historic moment. Water-based types are divided into three types: emulsion type, non-soap emulsion type and water-soluble type. The molecular weight of emulsions is 100,000-5 million, the particle diameter is 0.05-0.2 microns, and the solid content is generally 40-60%. Due to the emulsion polymerization method, a small amount of compound emulsifier is added during polymerization. Due to the presence of emulsifier, during the process of fusing and forming a film, part of it is squeezed to the interface between the film and the fabric, thus weakening the bonding strength with the fabric, making the The water pressure resistance of the product is affected to a certain extent. The water-soluble type is a special colloidal dispersion that introduces hydrophilic functional groups into the polymer and can be in a clear state in water. The molecular weight of the water-soluble type is generally around 100,000-200,000. The other part is squeezed to the outer surface of the film, causing a sluggish feeling on the film surface and causing the coated fabric to feel unpleasant. Non-soap emulsion type (also called emulsion-free) coating agents do not contain emulsifiers and are mainly used for fine coating and waterproof finishing of fabrics. The finished fabric can maintain its original style, has a soft hand feel, high fastness, smooth hand feel, high mechanical properties and good waterproof effect.
It has been reported in China that polyacrylate ultrafine emulsion was synthesized by emulsion polymerization. Its average particle size is below 50nm and its appearance is translucent colloidal mucus. 2D resin was selected as the external linking agent and fluorine-containing resin was used for post-water-repellent finishing. The coated fabric can achieve higher water pressure resistance and water repellency. At present, most of this type of domestic products are of the cross-linking type, and cross-linking agents must be added during application, which brings inconvenience to manufacturers. In recent years, some people in China have conducted research on the application properties of water-based ultramicroemulsion self-crosslinking polyacrylate fabric coating agents. The results show that it has excellent performance and broad application prospects.
Waterproof and breathable finishing agent
Fabrics treated with this type of coating agent have both waterproof and moisture-permeable functions. The waterproof and moisture-permeable mechanism relies on the formation of a large number of micropores during film formation. These pores are smaller than 2 microns, which can block water droplets (average diameter 100 microns), but allow water vapor molecules (average diameter 0.0004 microns) to pass through, thereby achieving waterproof and breathable properties. In order to improve the breathability and moisture permeability of polyacrylate processed fabrics, since the 1980s, Japan has dissolved acrylate copolymers containing hydrophilic groups such as carboxyl, hydroxyl, and nitrile groups in water-miscible organic solvents. The coating glue is made from the coating glue. After coating, it is treated with warm water to remove the solvent and solidify the copolymer. It is dried and dehydrated to form a microporous film on the fabric. This kind of coating adhesive uses wet coating to treat fabrics with good breathability and moisture permeability. Compared with dry coating, wet coating is more complicated, so it is imperative to develop fabric coating adhesives that are both dry coating and waterproof and breathable. Our country developed such products such as PP-3 in the mid-1980s, which are made of acrylate monomers.6. Glue overflow
Fabrics with sparse texture and hard feel are prone to glue seeping out of the fabric surface.
7. Colored yarns of light-colored fabrics are highlighted due to compounding.
For white fabrics, especially white woolen fabrics, fabric defects such as colored yarns in the white fabric are particularly prominent due to the background fabric after lamination.
8. Composite entrained foreign matter
During the PU composite production process, it is easy for impurities (such as hair, fiber scraps, etc.) to fly into the composite glue. When composite light-colored fabrics, the foreign matter entrained will appear on the cloth surface.
9. Curling
Elastic fabric and non-elastic fabric are bonded together and the elastic fabric is thicker than the non-elastic fabric. During the composite production process, if the surface tension of the fabric is not well controlled, it will easily curl.
Summary and measures
Top and back fabric selection
Best: consistent door width, consistent shrinkage, consistent thickness
1. If the difference in shrinkage is greater than 3 points, the fabric with a small shrinkage should be thicker than the fabric with a large shrinkage (determined by the specific sample).
2. The fabric before lamination should not be subjected to hydrophobic softening treatment, especially fluorine-containing waterproof treatment.
3. Try to avoid choosing white fabrics, especially white woolen materials, for lamination
4. High-value fabrics have narrower widths than low-value fabrics, and the difference in width cannot exceed 10CM, otherwise there will be greater waste.
5. Try not to use fabrics with production risks for lamination.
Composite process
1. For fabrics that require dry cleaning for ready-made garments, the PUR process should be selected for lamination.
2. When laminating, the fabrics should be aligned with the silk threads to avoid skewed wefts, twisting of straight threads, etc.
3. The mid-term maintenance treatment must be sufficient, otherwise the peeling strength will be poor.
4. Composite processing seems simple, but it has a lot to do with the experience, technology, and operational proficiency of the composite factory.
5. The composite fabric cannot be recombined. Even if it is peeled off, it will affect the yarn of the fabric, make it hard to the touch, and the yarn is easily punctured by needles.
6. Non-elastic high-density woven fabrics need to be compounded with film, otherwise the fastness will be poor.
Waterproof, antifouling, hydrostatic pressure, air permeability, water repellency, moisture permeability test
Hydrostatic pressure (WP):
1 Introduction
Hydrostatic pressure WaterProofness: The outdoor fabric industry customarily calls it water pressure resistance. The unit is expressed in mmH2O. It refers to the strength of water pressure per unit area. Under standard laboratory conditions, the fabric withstands the pressure of distilled water sprayed upward, and the maximum water pressure is recorded. For example, the water pressure resistance is 5000mmH2O, which means that the unit area can withstand a maximum pressure of 5m without leakage.
2. Common test standards
American standard AATCC 127;
Japanese standard JIS L1092B;
European standard: IS0 811;
3. Test method:
The water pressure resistance test is divided into two methods: before washing and after washing:
Pre-wash test: Domestic outdoor brands generally test the water pressure resistance value before washing, but do not test the value after washing. If the water pressure resistance value drops greatly after washing several times, it may drop by about 1000-3000mmH2O;
Post-wash test: Famous foreign outdoor brands usually test the water pressure resistance after 5 washes. THENORTHFACE even uses the method of testing the water pressure resistance after washing 20 times. Due to the test after multiple washes, the water pressure resistance value drops very significantly. Such a test The method is that any coating factory or film lamination factory must use better materials for processing. For example, the water pressure resistance of coated fabrics requires 5000mmH2O after 5 washes, so it must be at least 7-8000mmH2O before washing; of course, this requirement will cause The price is higher!
Air permeability (MAP):
1 Introduction:
Air permeability (Method Air Permeability): It means the performance of air permeability through fabric; under specified pressure difference conditions, measure the air flow rate vertically passing through a given area of the sample within a certain period of time, and calculate the air permeability. The air flow rate can be measured directly or converted by measuring the pressure on both sides of the flow aperture.
2. Test standards:
American Standard ASTM D737
European standard ISO 9237
Japanese standard JIS L1096;
Breathability units can be expressed in mm/s or cm3/cm2/s;
Water repellent:
1 Introduction:
Under the standard laboratory, use distilled water to spray on the sample through a funnel, and compare it with the waterproof standard sample to score the rating.
2. Test standards:
American Standard: AATCC 22;
European standard: ISO 4920;
3. There are three types of water repellent:
Ordinary waterproof (WaterRepellent, abbreviated as: W/R), water-resistant (DurableWaterRepellent, abbreviated as: DWR) in the outdoor fabric industry, and Teflon (TEFLON) waterproof;
Ordinary waterproof (W/R): After washing the clothes a few times, the surface will no longer be waterproof. Generally, ordinary waterproof is enough for outdoor leisure. If you often go hiking or go to a mountain with a certain altitude, the weather on the mountain is changeable and it may rain at any time. Ordinary waterproof clothing will not be waterproof if it is washed several times, causing the surface of the clothing to get wet, and wearing it will increase the weight on the body.
Super water repellent (DWR): Carbon 6 waterproof produced by Daikin in Japan can maintain an effect of 80 points (European standard level 3) after 20 washes; previously, carbon 8 waterproof can reach an effect of 80 points after 30 washes because it contains fluorine The quantity does not meet EU standards and has been banned by the EU.
Teflon (TEFLON), produced by DuPont in the United States, is very well-known. It has three-proof effects such as waterproof, anti-fouling, and oil-proof. The price is relatively expensive. If you buy this brand of waterproof, you can provide Teflon hang tags, but Teflon has the disadvantages of The water-repellent effect is not as good as Carbon 8 and Carbon 6;
Moisture permeability (MP):
1 Introduction:
Moisture permeability (abbreviated as: MP), moisture permeability is expressed in units of g/m2/24h, which means that under certain standard laboratory conditions, a specific humidity difference is formed on both sides of the sample, and water vapor enters through the sample On the dry side, by measuring the change in weight of the moisture-permeable cup over time, parameters such as the water vapor transmittance of the sample can be obtained.
2. Test standards and test methods:
There are two testing methods for moisture permeability: straight cup and inverted cup;
Cup correcting method: American standard ASTM E96 A, C, E; Japanese standard JISL1099 A1;
Pour cup method: American standard ASTM-E96, Japanese standard test JIS L1099B1;
This test uses pre-wash data!
�Introduction:
Moisture permeability (abbreviated as: MP), moisture permeability is expressed in units of g/m2/24h, which means that under certain standard laboratory conditions, a specific humidity difference is formed on both sides of the sample, and water vapor enters through the sample On the dry side, by measuring the change in weight of the moisture-permeable cup over time, parameters such as the water vapor transmittance of the sample can be obtained.
2. Test standards and test methods:
There are two testing methods for moisture permeability: straight cup and inverted cup;
Cup correcting method: American standard ASTM E96 A, C, E; Japanese standard JISL1099 A1;
Pour cup method: American standard ASTM-E96, Japanese standard test JIS L1099B1;
This test uses pre-wash data!
