material quality

Fabric and lining:

Mostly used for the material outside and inside the bag. 

Surface: The fabric should not have a drawstring, the stripes of the yarn should be clear and uniform in color, the number of horizontal stripes of the yarn should be sufficient, the thickness should be sufficient, and the yarn should be straight (can be tested by a measuring instrument); 

Rubber sole: the glue is firmly attached and will not be degummed Bottom, the rubber sole will not turn white (it will not turn white after grasping by hand, keep the original rubber background color); 

force: merge the car in the direction of horizontal and straight grain, and will not crack after pulling hard. Colored materials should also pay attention to whether there is a reinforcement color, especially for bright colors, it is more likely to cause staining, and the color matching is not good enough to find out that it is too late for the finished product!

Foam and sponge:

It is mainly used between the fabric and the bag's lining, and the finished bag cannot be seen. 

It mainly depends on whether the thick bottom and density are enough (whether one square has enough weight). Good cotton is least,ic and not easy to pull apart.

Foam and sponge

Net material:

It must be elastic, good in force, not easy to break, and there is no yarn breakage.

There are many types of webbing, such as plain weave, fine weave, pit weave, etc., but every kind of webbing has a standard weight. From the outside, check whether the two edges are smooth, whether the surface is uniform, no lint, no drawing, no dyeing, etc.

Zipper:

The quality of the zipper cloth and the slider is mainly distinguished by grade: such as grades A, B, and C, the more advanced the grade, the better the quality. Specifications are distinguished by size: such as size 3, 5, 8, 10, etc., the larger the number, the larger the size. Each size of the zipper has a standard weight, and weight is also the key to quality. From the outside, the main attention: it should be smooth when pulling, and there will be no feeling of unsmooth pulling. The sound is not very loud when pulling, and the zipper teeth can be pulled out by hand, and it is not easy to burst open. It is not easy to pull apart between the slider and the pull tab. The pull tab should be firm and not easy to be pulled apart, deformed, etc. Colored zippers should also pay attention to whether there is a reinforced chromaticity level. To avoid the phenomenon of easy dyeing with the fabric, the consequences will be serious.

Fabric knowledge

Now that we understand what a rucksack is, we must understand what a knapsack is. The rucksack vs. backpack vs. knapsack debate relies on the history of the term and its use when it comes to the latter. A knapsack is a smaller type of backpack, but people use the term primarily in Canada to refer to what Americans call backpacks or daypacks. The main difference is the size of this item.

yarn:

Definition of Denier number of yarn (fixed length):

Take a yarn with a length of 9000 meters, if the weight is 70G, it is called 70D, 210G is called 210D, and so on.

Definition of yarn count:

Take 1 pound of yarn, its length is several times the length of 840 yards, which is called several yarns, if the length is 10 times the length of 840 yards, it is called 10 yarns, and if it is 20 times the length of 840 yards, it is called 20 yarn, and so on, the larger the count, the finer the yarn (usually used for spun yarn).

type of yarn:

A. According to the material:

1. Natural fiber:

1) Plant fiber: cotton (COTTON) hemp (JUTE, LINEN, RAMIE)

2) Animal fiber: wool (WOOL) silk (SILK)

2. Synthetic fiber:

Nylon (Nylon) (NYLON) Teflon (Polyester) (POLYESTER also known as TETRON) Acrylic (ACRYLIC) Polypropylene (PP) Polyethylene (PE)

3. Man-made fibers:

Rayon (RAYON) is also called rayon (VISCOSE)

4. Blended fibers:

Long/staple blended yarn, there are two kinds of T/R T/C

B. According to brightness: semi-gloss yarn/glossy yarn/triangular glossy yarn

C. In terms of processing points:

1. Raw silk (unprocessed): UDY (unstretched) POY (semi-stretched) FOY (full-stretched)

2. Processing silk

3. Spinning

4. Burden yarn

D. According to the number of strands of yarn: single strand double strand multiple strands

Discrimination of yarn material:

1. Cotton: Immediate burning, stable flame, gradually extinguished, white smoke, burnt smell, gray ash, SOFT.

2. Lingying: Burns immediately, the flame is stable, extinguishes immediately, white smoke, burnt smell, no ash, SOFT.

3. Nylon: First shrink, curl, melt, gradually burn, white smoke, like celery, gray lumps, shiny.

4. Tedolon: shrink, curl and melt first, then burn gradually, producing black smoke, odor, black lumps, dull.

5. PE: First shrink, curl, melt and then burn immediately, with black smoke, paraffin smell, and yellow-brown lumps.

6. PP: It melts first and then burns quickly, the flame jumps, black smoke, pungent smell, black irregular lumps.

Germ Cloth:

A. According to the weaving method (different looms):

1. Knitted fabric: mesh, megacloth, plush, shearling, wear-resistant fabric, KEVLA L LYCRA.

2. Plain weave: Tafta Oxford CORDURA BALLISTIC.

3. Twill: 3/1 twill, 2/2 twill, large twill, cross jacquard, plaid, sardine

4. Jacquard: dyed yarn plaid curtain fabric LOGO jacquard bed sheet tablecloth

5. Non-woven fabric: Lixin cloth needle ginned cotton (pay attention to the thickness/yard weight/texture/color)

Plain weave, twill weave, and jacquard fabric are all made of warp and weft yarns cross-woven into their fabric structure. Depending on the material/number of warp and weft yarns and different weaving methods, various fabrics of different specifications can be changed. The specification representation method for:

420D (warp denier) * 420D (weft denier) / 50T (warp yarn) * 36T (weft yarn number) knitted fabric is knitted by warp and weft yarns in the form of loops, usually divided into warp and weft yarns. There are two kinds of knitting and weft knitting. The specifications are often expressed in Danny number/yard weight/width.

Common specifications of nylon cloth:

70D: 70D*170T+PU1 70D*190T+0.3MM PVC 70D Diamond+PU2+WR/

210D:210D*116T+PU1 210D*116T+PU2 210D*118T+0.35MM plain weave PVC

420D:420D*86T+PU2 420D*86T+0.4MM PVC 420D Oblique+PU2+WR 420D Cross Jacquard PU2+WR

840D+PU2/PVC 1680D+PU2/PVC

CORDURA: 500D+PU2+WR/PVC 1000D+PU2+WR/PVC

Common specifications of Tedlon fabric:

75D printed cloth+0.3MM PVC 150D herringbone oblique+PU1 300D*110T+PU2/0.3MM PVC

600D*300D*64T+0.5MM PVC 600D*64T+0.55MM PVC 600D*76T+PU2+WR

1200D+PU2+WR/0.6MM PVC 1800D+0.65MM PVC

Other commonly used cloth specifications:

1. PP cloth: 1000D PP plain weave+PU2+WR 1200D PP twill+PU2+WR 350D PP twill+PU2+WR

PP cloth has the characteristics of lightweight, good fastness and color fastness, good strength and heat resistance, anti-fouling, and antibacterial properties, and can be naturally decomposed.

2. PE-coated cloth: also known as PE plastic cloth, which is formed by coating the upper and lower sides of PE plain-woven cloth with PE.

3. Warp and weft blended fabric: 420D*300D N/T two-color cross jacquard+PU2 (with two-color effect) T/linen: 300D*12’S/2+0.4MM PVC (the import tariff to the United States is lower)

Dyeing and finishing process:

Preformed cloth→coloring→distributing cloth→rolling cloth→casting dyeing (sizing/refining/dyeing)→setting (resin/water splashing)→printing/gluing or gluing after packaging

1. Coloring should consider post-processing and pasting PVC

2. Dyeing is divided into normal temperature (nylon) and high temperature (Teflon/plain weave/wrinkle cloth), pay attention to color fastness (sunlight/washing/rubbing/UV resistance) and non-azo dyes (European Community requires all fabrics No azo dyes)

3. Send the dyed color cloth to the setting machine, fix the yarn structure at a high temperature of 140~190℃, control the width, feel (add resin), and do water-repellent or fire-proof processing.

4. After the color cloth is completed, there are the following treatments:

1). Printing: ink (roller printing) paste printing (rotary printing) paper printing (thermal transfer) automatic screen

2). Hot pressing: The pattern is formed by contacting the cloth surface with the patterned roller at a high temperature

3). Sanding/Raising/Brush: Contact the cloth surface with sandpaper/needle/brush to form a fluffy feeling

4). Gluing: apply a layer of glue (PU/ULY/color glue/waterproof and breathable) on the cloth surface to achieve

To the effect of waterproof/fixed yarn and reinforcement, pay attention to the requirements of waterproof and moisture permeability, rubber surface haze, and hand

Don't feel too hard.

5). Glue: mainly divided into PVC glue/CPU glue (ie EMB glue)/TPE glue/FLEX glue, etc.

(1) PVC glue: Laminate the PVC film with the cloth to achieve the effect of waterproofing, yarn-fixing, and strengthening. Pay attention to the feel/texture/thickness/cold resistance and low toxicity.

(2). CPU glue: evenly spread the CPU glue on the cloth in the form of lamination, the same can be achieved.

The effect of waterproofing/reinforcing/fixing yarn. It has low toxicity, can be decomposed naturally, and does not produce toxic gas when burning. Pay attention to the requirements of hand feel/texture/gluing color/cold resistance.

(3). TPE/FLEX glue: the most environmentally friendly glue, used to replace PVC/EMB and other glues, TPE glue is relatively soft.

4). Lamination: Refers to laminating the cloth with PU foam/EVA/sponge to achieve reinforcement or other functional effects (padding/heat preservation/pressure resistance)

Leather can be divided into:

A. Natural leather: (the elements of composition are: thickness / texture / haze / coloring or dyeing)

1. Cowhide: genuine leather (top layer leather) is used for leather shoes/leather clothing/high-grade leather goods, and Erlang leather (second layer leather) is used for general leather goods such as sports shoes.

2. Sheepskin: lambskin is used for leather clothing/shoes/gloves, etc.

3. Pigskin: general leather goods/gloves

4. Crocodile skin and ostrich skin are used for high-grade leather goods.

For all-natural leathers, at least 30% of the loss should be pre-grabbed when calculating and cutting.

B. Artificial Leather:

1. PVC rubber:

1) Thickness (0.8MM~2.0MM mainly comes from the foam layer)

2) Width (36” 48” 54”)

3) Base fabric (T/C 10P 6P knitted fabric, fleece fabric, non-woven fabric, pay attention to white fabric or dyed fabric)

4) Embossing

5) Surface Treatment (Haze Printing Flocking Calendering Pearlescent Mirror)

6) Hand feel (soft hardness high elasticity NAPA)

7) Use (bags, bags, shoes, shoes, furniture, vehicles)

8) Special requirements (cold resistance, vulcanization resistance, yellowing resistance, tortuous resistance, friction resistance, slip resistance, low toxicity)

2. PU leather:

1) Thickness (0.6MM~1.2MM mainly comes from the thickness of the cloth bottom)

2) Width (36” 48” 54”)

3) Base fabric (similar to PVC leather)

4) Surface treatment (similar to PVC skin)

5) Embossing (the release paper forms finer lines)

6) Uses (bags, shoes, furniture, gloves)

7) Special requirements and feel

3. PVC tape: the elements are

1) Thickness (0.1MM~1.0MM)

2) Texture (roller formation)

3) Hand feel (general hand, hard, semi-hard)

4) Special requirements (cold resistance and low toxicity)

4. Cloth-like PVC leather:

1) Texture (imitation 210D imitation 420D imitation 600D imitation 1680D imitation sardine pattern)

2) Width (56”~58”)

3) Fabric backing (70D, 210D, 200D/400D, 600D/300D, pay attention to whether it is dyed)

4) Total thickness (0.3~0.5MM)

5) Hand feel and special requirements

5. PVC clip mesh:

1) It is made of nylon or Teflon and laminated by PVC double layer (so it can do a two-color effect)

2) Thickness (0.25~0.65MM)

3) Base fabric (210D, 420D, 250D, 840D, 600D)

4) Width (54”)

5) Texture

6) Pay attention to special requirements such as haze/cold resistance/low toxicity