Footwear is a tool used by people to protect their feet from injury. So how much do you know about footwear? The following is the content about the basic knowledge of footwear compiled by the editor of XueLa. I hope you like it!
1. Knowledge about shoes
1. The length of shoes sold for export is 8% in length and the girth is 4% in advance. The length of shoes sold domestically is 6% in length and the girth is 3.75%.
2. The inner and outer sides of the human foot are of different lengths. The inner side is shorter and the outer side is longer. Therefore, when making shoes, if the shoe decoration on the panel has a left-right symmetrical pattern, the inner shoe decoration should be shorter than the outer side. Only when the shoe decoration is 2-3 centimeters will it feel visually symmetrical. In addition, the inner panel of the shoe should be made wider and shorter, and the outer panel should be longer and narrower, especially for flip-flop shoes.
3. Three kinds of glue are needed to make a pair of shoes. Powder glue is used to attach the midsole, all-purpose glue is used to bond the panel and midsole, and heat-resistant glue is used to glue the outsole. The midsole and outsole must be glued on both sides.
4. The toes exposed on the toe of sandals are generally 4 and a half toes. The most comfortable position is that the thumb exposes the first joint and the little finger only exposes a little bit.
5. The midline length of the sandal panel (that is, the shortest part of the panel) is about 4-4.5 cm, which is the most comfortable.
6. Toluene can erase the printing on the shoe surface
7. The height of the back strap of the sandal between the heel and the midsole is 0.5-1 cm different from the length from the heel to the bonding point between the back strap and the midsole. The length from the heel to the joint between the back strap and the midsole is about 3.5-4 cm.
8. The height of the back strap of sandals should be high on the inside and low on the outside, because the ankle joint is high on the inside and low on the outside.
9. The interface between the shoe surface and the bottom of the midsole is generally about 2.2 cm.
10. Generally, the right foot of a human foot is wider and longer than the left foot.
2. Shoemaking process
1. Shoemaking assembly line process:
Stamping the midsole - making the midsole - making the panel - pulling the top - brushing the glue on the upper assembly line and sticking the shoes - shaping and pressing the shoes - air drying - inspection - cleaning the upper - packaging
2. Shoemaking process in the boardroom
a, paper pattern
Stick the shoe material with tape - draw the shoe pattern on the shoe material with tape and determine the position of the flower head - cut the pattern - copy the shoe pattern on the tape on the cardboard to make a paper pattern
b, surface making plate
Use the paper pattern to cut out the prototype of the panel - trimming - stitching - applique head
c, midsole
Draw the midsole paper pattern - use the paper pattern to cut out the midsole - press with your hands to create the midsole curvature - apply glue to the midsole fabric
d. Use shoe material to bond the panel and midsole
e, attach the outsole
Three, tips
1. Reasons for shoe degumming
a. The pressure of the press is not enough after attaching the bottom;
b. The upper and sole are windproof;
c. The glue has dried and is no longer sticky;
d. When fitting, the fan blows to the front of the sole, causing it to become non-stick.
2. How to tell whether the glue is completely dry:
a. If you apply water-based glue, after the bottom or surface comes out of the oven, if there are white spots on the surface of the glue, it means that the glue is not dry;
b. What you are applying is oily glue. After leaving the oven, gently scrape the surface of the glue with your fingers. If it can slide, it means the glue is not dry. Otherwise, it is the opposite.
3. Treatment agent and hardener
a When bonding the outsole, the treatment agent is used to corrode the attachments of the sole and make the sole easy to glue, and all treatment agents must be completely dry, otherwise it will have the opposite effect.
b. How to identify whether the treatment agent is dry: smell it with your nose. If there is no smell, it means the treatment agent has dried.
c. If the outsole material is relatively soft, you need to add a hardener to the glue to make the sole harder.
4. Tips on footwear inspection
Appearance requirements
a, Pair matching includes color difference, long hair and short hair, single foot, toe size, heel height, etc.;
b. Cleanliness includes silver pen lines, glue contamination, car oil, rust, dust, thread, finished product discoloration, fading, etc.;
c. Skew includes the various accessories of the upper (toe cap, back bag, tongue, decorations, joints, etc.) as well as the skew of the upper and upper sole, midsole, etc.;
functional requirements
a, can’t be worn, including paper version errors, possible wrong use of lasts, random codes, etc.;
b. The adhesive strength of the glue is not enough to meet the minimum standards required by the customer or it can be easily pulled off by hand;
c. Whether the inner surface is folded, which may cause scratching on the feet;
Packaging
a, outer box, especially outer box printing, including printed font size, content, location, etc. The other is the outer box specifications, including size, material, gross weight and net weight, etc.;
b. The inner box includes size, color, various labeling, printing, whether the inner box is the wrong shape, wrong code, wrong color, whether desiccant is needed, whether it needs to be paired, etc.;
c. Short packaging. Every time the goods are inspected, it is necessary to check whether the box is full, and at the same time, the box must be drawn out to avoid factory cheating.
4. Materials
1. PVC is a little harder than TPR, and it has slippage, that is, the friction with the feet is smaller.
2. PVC materials of poor quality will produce oil when heated in an oven. If such materials are used to make shoe soles, the oil will cause the glue to lose its viscosity, making it difficult to bond or not strong enough.
3. The grades of leather are arranged from high to low.
First layer of skin--second layer of skin--top layer of skin--second layer of skin
The difference between top layer of skin and second layer of skin
The top layer of skin has good feel and softness, and it recovers quickly after being pressed without any obvious wrinkles.
The second-layer skin has poor flexibility and will have cotton-like wrinkles after being pressed, and the wrinkles will recover slowly.
4. How to identify whether the material has been laminated or not?
Use your fingernail to try to scrape. If there is resistance on the material and the scratching is not smooth, it means the material has no lamination. On the contrary, if it is smooth and there is no resistance, it means the material has lamination. Otherwise, it will be difficult to distinguish it with the naked eye.
Five, color matching
1. Different places have their own favorite color matching methods. The color matching of shoes should be based on the preferences and cultural matching of different places. For example, the color characteristics of countries with small populations are obviously easy to form unified color matching habits and color concepts.
2. Collection of preferred and taboo colors in several countries
South Korea: Like red, yellow, green, bright colors; taboo black and gray
Japan: Prefers soft colors; black, dark gray, and black and white are taboo
Italy: Likes bright colors
West Germany: Likes bright colors
Canada: Prefers plain and static colors
North America United States No special hobbies No special taboos
Footwear Basics Q&A
1. How to distinguish the quality of leather shoe outsoles?
The outsole materials of leather shoes include lemon glue, polyurethane, modified polyvinyl chloride, etc. In the national industry standards for leather shoes, the folding resistance, wear resistance and hardness of the outsole are stipulated. A folding resistance and wear resistance testing machine is required. Use a hardness tester to test. When choosing shoes, press the soles with your fingers. The soles should be elastic. If you hold the soles with your hands, no small pieces will fall off. They should not be sticky to the touch and should be soft when bent. At present, there are many quality problems with the outer soles of lemon rubber shoes. Breakage and block detachment occur from time to time. This is because sole manufacturers do not care about product quality for profit. The rubber content of rubber soles is low and recycled rubber and other fillers are used. Excessive use will reduce the quality of the soles.
2. What is the function of the steel hook of leather shoes? How to distinguish the good from the bad?
Every men's and women's leather shoes have a steel hook (except for flat shoes and wedge shoes). It is installed between the outsole and midsole at the arch of the foot (waist window). It is the backbone of the shoe and maintains the curvature and stability of the sole. The stabilizing effect of the heel is particularly important for mid- and high-heeled shoes. The steel hook standard for leather shoes stipulates performance indicators such as longitudinal bending stiffness and hardness. When choosing shoes, you can use your hands to press the inner sole of the shoe with moderate force. It is better if it is not soft or deformed. If after wearing the shoe, you find that the heel is skewed (it does not mean that the heel is not strong), the sole is hollow or uncomfortable. You can check whether the hook is broken. If it breaks within the three guarantee period, it can be returned or exchanged.
3. Why are leather shoes unglued?
It is common for adhesive leather uppers and soles to be unglued due to weak adhesion. There are many reasons for the glue to open, mainly due to improper selection of raw materials and improper process control in the factory. Rubber soles and leather can be bonded with neoprene, but imitation leather soles and polyurethane soles that contain more resin components are difficult to adhere to. Polyurethane finger glue or other adhesives must be used to adhere firmly, because one kind of adhesive does not Suitable for any material. Before bonding, the soles and uppers need to be polished and fluffed, glued several times and baked, and then pressed with a laminating machine to stick firmly. The quality of the bonding of leather shoes is controlled by the peel strength index. These The indicators should be measured with a peel tester. When choosing shoes, pay attention to check whether the upper and sole joints are firm and whether the glue has been peeled off. When wearing them, be careful to prevent rain and ice. Leather shoes are prone to glue peeling when exposed to water.
4. Is the quality of cardboard used as the inner bottom reliable?
In the past, leather shoe insoles were made from pig and cow insoles. Nowadays, natural leather resources are decreasing. Substitute materials are used to replace some natural materials. For example, cardboard for shoe insoles is widely used at home and abroad. The hygroscopicity, air permeability, flex resistance, interlayer peel strength, tear resistance, dimensional stability, etc. of good quality shoe insole cardboard can fully meet the usage requirements. If the insole cardboard breaks, shrinks and deforms after wear, Hardening, delamination, etc. are all considered to be of unqualified quality.
5. What are the quality requirements for the main heel and Baotou?
The main heel is located at the connection between the back and bottom of the leather shoe. The heel is located at the front of the shoe. They are designed to prevent the leather shoe from deforming and should be installed between the upper and the lining of the shoe. Use your thumb to press the toe and it will not be soft or deformed. Use your thumb and index finger to press the lower 2/3 of the main heel and it will not be soft or deformed. The size and height must be consistent to be qualified.
6. How to check the inside of shoes?
You can put your hand into the leather shoe chamber to check whether there are any defects that may affect the wear, such as whether the insole is up to the toe (not short of the toe), whether the inside of the shoe is flat, and whether the inside of the shoe is away from the nail tip. Not equal to nail tail.
7. Why do some leather shoes change color and become stained after applying shoe polish?
There are two reasons for this phenomenon. One is the quality of shoe polish. If the solution of shoe polish can destroy the leather coating of the shoe upper, it can cause discoloration and flowering of the shoe upper. The other is that there is a kind of leather commonly known as 'oil leather', which is cow front leather. A kind of high-end product with extremely thin coating, strong adsorption and permeability, and good hygienic performance. If there is a problem with the quality of the shoe polish, or when the oil is removed, it is squeezed directly onto the upper of the shoe, and spots will form on the oil stained spots. In addition, Drops of ink, hair dye, or gasoline will cause pollution. Therefore, you should be careful when wearing it.
