Sole type one, sole
Sole type 1, Simply conclusion that the sole material is use the natural rubber or synthetic rubber.
(1) Natural rubber: the advantage of natural rubber is that it is very soft, excellent elastic , suitable for various sports, but the disadvantage is also very obvious that it is not wear-resistant,which is use most for Indoor sneakers.
Sole type 2, synthetic rubber is divided into wear-resistant rubber, environmental protection rubber, air rubber, sticky rubber, hard rubber, carbon rubber.
(1) wear-resistant rubber: the wear resistance and toughness of wear-resistant rubber are very good, so it is very durable, which is used most on the sole of tennis shoes.
(2) Environmentally friendly rubber: also known as recycled rubber, this rubber sole contains 10% more recycled rubber, the main purpose is to environmental protection.
(3) Air rubber: the rubber contains air and has a certain shock absorption function, but not very wear-resistant and not widely used.
(4) Viscous rubber: viscous rubber is characterized by good flexibility, and very non-slip, most used in indoor sports shoes.
(5) Hard rubber: hard rubber is the most comprehensive rubber in the sole rubber material, tough and non-slip and very wear-resistant, naturally it is very widely used. Multifunctional shoes and basketball shoes are mostly made of this rubber to do the sole.
(6) Carbon rubber: carbon elements are added to the ordinary rubber material, making the rubber more tough and wear-resistant, most using for the running shoes, and the back part of the sole of the running shoe will leave BRS letters to indicate the use of carbon rubber on the sole.
Sole type 3, rubber sole: This sole is not common, the raw material of this bottom is industrial glue, stirring through the blender, and then can into the mold heating molding, which is characterized by soft and very non-slip.

Sole type two, middle sole
type 1, Many people will know, that is, PHYLON mid-sole, and EVA mid-sole is very common. In fact, both of these mid-soles belong to the same attribute category (engineering plastics), but why are there different names? PHYLON originated in the United States, in earlier shoe mid-sole are called PHYLON, and there is no EVA mid-sole and PHYLON mid-sole, later with the continuous development of footwear products, in Taiwan and South Korea's some big brand shoe product research and development factory as the source, the name of the mid-sole is more systematic, we now have what we call EVA mid-sole. Here I will talk about the difference between EVA mid-sole and PHYLON mid-sole in popular terms.
Now the shoes with the most sole is PHYLON, which is very light, good flexibility, with good cushioning performance, also it called secondary foaming. EVA mid-sole is also very light, but the cushioning performance and elasticity are far less than PHYLON mid-sole, but the cost is much lower than it, EVA mid-sole is called a foam. The reason why they have the same properties, the name is different, the core  reason is that PHYLON is a second foaming, and EVA is one time foaming.
(1) One time foaming: the material is injected into the mold and heated at high temperature after one time molding of the shoe mid-sole, which is called one time foaming mid-sole, that is the EVA shoe mid-sole.

(2)Secondary foaming: After the material is injected into the mold, the molded mid-sole is fired after two high temperature heating, which is called the secondary foaming mid-sole, that is we often say PHYLON mid-sole. The hardness is also controlled by temperature, in the process of firing  PHYLON sole, the higher the temperature, the higher the density, the harder it is. The smaller the fire, the softer the PHYLON will be naturally burned, so the quality of the shoe soles can not be measured by weight or the degree of softness.

(3) Coating cloth burning middle sole: Coating cloth burning middle sole is also PHYLON middle sole, but the designer in order to pursue the overall design feeling and use a shoes making technology, the good example is that the sole and the upper with the same kind of fabric, making the shoe body and the sole to the whole combination,which is also a bright spot on the production process of this shoe. To achieve this process is to use the selected fabric to wrap the formed PHYLON mid-sole, and burn it at high temperature in the mold, which becomes the  the middle sole of fabric texture.
2, PU mid-sole: beside of PHYLON mid-sole and EVA mid-sole, PU mid-sole is also very common, because of the  advantage of better elasticity and toughness.

type 3,Wrap mid-sole: Many shoes now use a built-in mid-sole structure, also known as the wrap mid-sole. Like the familiar T-MAC series, Nike's style series belong to the wrap middle sole structure, which is from the appearance of the sole consist of the upper and the sole two parts, but the structure is still composed of the sole, the mid-sole and the upper three parts, but the mid-sole package in the inside of the upper.
Sole type 3, insole and integral sole

Sole type 1, insole: The insole can also be counted as a form of the wrap mid-sole, and the difference is that the insole structure is wrapped in the sole, even if it is the insole structure, rather than the overall rubber sole as seen on the outside, in fact, the inside of the rubber sole is covered with the mid-sole, this mid-sole is also called MD mid-sole, which belongs to a kind of EVA foam.

Sole type 2, integral sole:
(1) Integral sole is a common EVA foam molding sole, with low cost and , and poor anti-slip, the sole dipped in water is like wearing roller skates. Reebok's 3D sole is the best "spokesperson" for this EVA of one time molded sole.
(2) PU overall sole: Adidas and Nike is very few to use this sole, PU sole is a low-temperature forming sole with a lightweight, but not suitable for water, chemical reactions will occur after encountering water, and layer by layer of corrosion.
(3) Pure rubber sole: pure rubber sole is mostly used for outdoor hiking shoes, or work shoes, electrician shoes. The whole sole is composed of rubber, the advantage is wear-resistant and non-slip, the disadvantage is that the weight is too heave. Caterpillar's work shoes generally use this sole, also called the insulated sole.