COMPOSITION FOR MANUFACTURING LIGHTWEIGHT FOOTWEAR HAVING IMPROVED HEAT-RESISTANCE AND LIGHTWEIGHT FOOTWEAR MANUFACTURED USING THE SAME

• US 20190322847A1
• Filed: 04/22/2019
• Published: 10/24/2019
• Est. Priority Date: 04/20/2018
• Status: Active Grant

• Current Assignee: Korea Institute Of Footwear & Leather Technology, Nano-Tech Ceramics Co., Ltd.
• Original Assignee: Nano-Tech Ceramics Co., Ltd.
• Inventors: JEONG, Sang Ok, PARK, Sang Young, HAN, Dong Hun, KIM, Young Min, LEE, Dan Bi
• Granted Patent: US 11,396,591 B2
• Time in Patent Office: Days
• CPC Class Codes: A43B 1/009 made at least partially of washable material
• CPC Class Codes: A43B 1/10 made of rubber
• CPC Class Codes: C08J 2201/026 Crosslinking before of after foaming
• CPC Class Codes: C08J 2323/06 Polyethene
• CPC Class Codes: C08J 2323/08 Copolymers of ethene C08J2323/16 takes precedence
• CPC Class Codes: C08J 2423/06 Polyethene
• CPC Class Codes: C08J 2423/08 Copolymers of ethene C08J2423/16 takes precedence
• CPC Class Codes: C08J 2471/02 Polyalkylene oxides
• CPC Class Codes: C08J 9/0023 containing oxygen
• CPC Class Codes: C08J 9/0042 containing silicon
• CPC Class Codes: C08J 9/0061 characterized by the use of several polymeric components
• CPC Class Codes: C08J 9/0066 Use of inorganic compounding ingredients
• CPC Class Codes: C08K 2003/2241 Titanium dioxide
• CPC Class Codes: C08K 2003/2296 of zinc
• CPC Class Codes: C08K 2003/265 Calcium, strontium or barium carbonate
• CPC Class Codes: C08K 2003/267 Magnesium carbonate
• CPC Class Codes: C08K 2003/3045 Sulfates
• CPC Class Codes: C08K 2201/003 Additives being defined by their diameter
• CPC Class Codes: C08K 3/04 Carbon
• CPC Class Codes: C08K 3/22 of metals
• CPC Class Codes: C08K 3/26 : Carbonates; Bicarbonates
• CPC Class Codes: C08K 3/30 : Sulfur-, selenium- or tellurium-containing compounds
• CPC Class Codes: C08K 3/36 : Silica
• CPC Class Codes: C08K 5/053 : Polyhydroxylic alcohols
• CPC Class Codes: C08K 5/092 : Polycarboxylic acids
• CPC Class Codes: C08K 5/098 : Metal salts of carboxylic acids
• CPC Class Codes: C08K 5/14 : Peroxides
• CPC Class Codes: C08K 5/34924 : containing cyanurate groups; Tautomers thereof
• CPC Class Codes: C08K 5/54 : Silicon-containing compounds C08K5/0091 takes precedence
• CPC Class Codes: C08L 2207/062 : HDPE
• CPC Class Codes: C08L 2207/066 : LDPE (radical process)
• CPC Class Codes: C08L 23/06 : Polyethene
• CPC Class Codes: C08L 23/0815 : Copolymers of ethene with aliphatic 1-olefins
• CPC Class Codes: C08L 23/0853 : Vinylacetate

Abstract

The lightweight footwear of the present invention maintains excellent durability and improves heat resistance, so that contraction percentage due to a change with the passage of time is significantly low, rarely causing deformation, and thus, the lightweight footwear may be used in a high temperature and sanitary environment. In addition, the present invention solves the problem of the occurrence of premature foaming due to injection molding and a pattern on the appearance due to dispersion failure, thereby facilitating injection molding.

Claims

1. A composition for manufacturing lightweight footwear having improved heat resistance, the composition comprising a thermoplastic polymer mixture including a first polymer comprising at least one selected from the group consisting of an ethylene vinyl acetate copolymer, an ethylene octene copolymer, and an ethylene butene copolymer and a second polymer having a melting point ranging from 100°

C. to 140°

C., a filler, a foaming agent, a crosslinking agent, and a reactive additive,

wherein the filler is contained in an amount of 5 to 50 parts by weight with respect to 100 parts by weight of the thermoplastic polymer mixture and has a particle diameter less than 20 μ

m.

3. The composition of claim 1, wherein

the filler is contained in an amount of 10 to 40 parts by weight with respect to 100 parts by weight of the thermoplastic polymer mixture, and the reactive additive is contained in an amount of 3 to 12 parts by weight with respect to 100 parts by weight of the thermoplastic polymer mixture.

4. The composition of claim 1, wherein

the second polymer is at least one selected from among low density polyethylene (LDPE), linear low density polyethylene (LLDPE), and high density polyethylene (HDPE).

5. The composition of claim 1, wherein

the filler is at least one selected from the group consisting of calcium carbonate, magnesium carbonate, silica, carbon black, and calcium sulfate.

6. The composition of claim 1, wherein

the reactive additive is at least one selected from the group consisting of a silane coupling agent, polyethylene glycol, polypropylene glycol, and itaconic acid.

7. The composition of claim 1, further comprising:

an ethylene vinyl acetate copolymer having a melting index of 15 to 400 to prevent the occurrence of premature foaming during footwear manufacturing using the composition for manufacturing lightweight footwear having improved heat resistance,

wherein the ethylene vinyl acetate copolymer having the melting index of 15 to 400 is contained in an amount of 5 to 15 parts by weight with respect to 100 parts by weight of the thermoplastic polymer mixture.

8. A lightweight footwear using the composition for manufacturing lightweight footwear having improved heat resistance of claim 1.

9. The lightweight footwear of claim 8, wherein

the lightweight footwear satisfies both of the following conditions (a) and (b):

0.3≤

A₁₀₀≤

1.5 

 

(a)

wherein A₁₀₀ denotes shrinkage (%)=(I₀−

I)/I₀×

100, I₀ denotes length of test piece of lightweight footwear before experiment, and I denotes length of test piece after the test piece was left in a convection oven and a steam sterilizer at 100°

C. for 15 minutes and then stabilized at room temperature for 30 minutes or longer.

10.5≤

B≤

13 

 

(b)

wherein B denotes internal tearing strength, which was measured using a test piece of lightweight footwear having a thickness 3 mm according to a method defined in KS standard KSM 6518.

10. The lightweight footwear of claim 9, wherein

the lightweight footwear further satisfies the following condition (c):

1.2≤

A₁₂₀≤

2.3 

 

(c)

wherein A₁₂₀ denotes shrinkage (%)=(I₀−

I)/I₀×

100, I₀ denotes length of test piece of lightweight footwear before experiment, and I denotes length of test piece after the test piece was left in a convection oven and a steam sterilizer at 120°

C. for 15 minutes and then stabilized at room temperature for 30 minutes or longer.

2. A composition for manufacturing lightweight footwear having improved heat resistance, comprising a thermoplastic polymer mixture including a first polymer comprising at least one selected from the group consisting of an ethylene vinyl acetate copolymer, an ethylene octene copolymer, and an ethylene butene copolymer and a second polymer having a melting point ranging from 100°

C. to 140°

C., a filler, a foaming agent, and a crosslinking agent,

wherein the filler is contained in an amount of 5 to 10 parts by weight with respect to 100 parts by weight of the thermoplastic polymer mixture and has a particle diameter less than 20 μ

m.