JPS5883902A - Reinforcing material of shoe - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] Footwear includes counters, etc. that reinforce the heel part.
reinforcing materials (inters). Such members are often made of thermoplastic materials, and after they are placed into the sub-assembly of the shoe, they are heated to soften and form the desired shape.

The present invention improves thermoplastic reinforcing members for reinforcing shoes by making it possible to heat-mold the reinforcing members without heating other heat-sensitive parts of the shoe as much as possible. This improvement is made by dispersing the magnetic material into the reinforcing material and exposing it to the high-frequency magnetic field of an induction heating coil to heat and soften the reinforcing material, making it possible to mold the reinforcing material into a desired shape. be.

In a preferred embodiment, the magnetic material consists of magnetic iron oxide powder and particles of magnetic iron powder. The reinforcement includes a coating of heat activated adhesive, the adhesive being activated under conditions that soften the reinforcement.

Virtually any thermoplastic material having the desired properties for a given application can be included in the reinforcement, since the need to consider heating properties is reduced. The frequency and exposure time of the magnetic field are selected appropriately to achieve the desired degree of softening of the thermoplastic material and adhesive used.

Below, a description of the drawings and the construction and operation of the preferred embodiments will be described.

FIG. 1 is a perspective view of the shoe counter of the present invention.

FIG. 2 is a cross-sectional view of the counter of FIG. 1 taken along line 2--2.

As shown in Figure 1, it is counter-shaped, flat, and has a thickness of 0.
．． A sheet 10 of 0.040 inches (0.1c) has a plastic layer 12 and an adhesive layer of 1400.04 inches (0.1c).
m) It is based on the following.

The composition of the plastic layer 12 is as follows.

Composition Weight percent Surly [5urlyn) 1605 C engineering 7
-Meth 75 acrylic acid ionomer plastic resin*.

(7 Yubon Co., Ltd. trade name) Magnetic iron oxide powder (variety "M-25" (trade name); 15 cents Pea Ridge Iron Ore Division manufactured by Joe Minerals Co., Ltd.'s Pea Ridge Iron Ore Division
n of St, Joe Minerals) Fe2o
3) Magnetic iron powder (“minus 100 type CAR,” (Rin Yu name); 1゜Peerless Metal No.
The layer 12 made of lessMetal Powders is made by mixing iron oxide powder and iron powder in liquid or semi-liquid resin, and molding the mixture into a sheet by a conventional method.
Finally, the counter is cut and shaped using conventional methods.

The heat-activated adhesive layer 14 is made to adhere by a conventional coating method. In a preferred embodiment, the adhesive is EV
A resin (vinyl acetate 28%) 55%, hydrocarbon resin viscosity imparting agent (“Piccofin A-lro 5” (Picc
o-fin A-135M trade name) (Hercules Inc.,
) 30%, and wax (“Parafuri 7”)
RG [Paraflint RG] (trade name); manufactured by Moore & Manger Company [MOOre
& Munger Co, ]) 15%.

The upper half-assembly of the shoe, which includes the counter 10 (usually sewn in a U-shape), is made using the high-frequency magnetic field (2) of an induction heating device currently used industrially for bonding plastic sheets, etc. , 8 MHz.

2.0 amp, 5 kilowatt generator) for 16 seconds. This device has a U-shaped coil with a radius of 2 A inches (6.35 cIrL) for inserting the upper shoe subassembly.

The magnetic field causes the iron particles and iron oxide particles in the plastic layer 12 to heat the sheet 10, causing the counter 10 to soften and conform to the desired shape of the heel. At the same time, the adhesive 14 is exposed to heat (in a preferred embodiment
Melt by 0F (127°C) and place on counter 1o
Glue to the inside of the top and lining. Adhesive 14 has a melting point at the temperature generated to soften plastic layer 12 and also has good heat seal bonding properties.

The reinforcement of the present invention can also be made using plastic resins, such as polyethylene and polypropylene, which cannot be practically 1C activated according to the prior art. The risk of damage to other parts of the shoe upper subassembly due to overheating is eliminated by the present invention.

Other implementations are within the scope of the claims.

The reinforcing material may be a material plate for the toecap.

For example, the thermoplastic material used as the reinforcing member may be any suitable material or mixture thereof, the choice of which will depend on the desired properties such as degree of stiffness.

Similarly, the magnetic particle components can be changed depending on the application. Generally, the magnetic component is present in a proportion of between about 15 and 25% by weight of the reinforcing member.

Iron oxide and iron may be used alone or -
They may be used together, and the particle sizes of both may be varied. Larger particle sizes have a greater effect on the physical properties of the plastic than smaller particle sizes.

Examples of other suitable thermoplastic-containing reinforcements include:
It has the following composition.

1 “Surlyn 1605” 80
Iron powder 10 Iron oxide.

2 Surlyn 1605 72 Iron powder 20 Styrene-maleic anhydride copolymer 8 (“Dy
1ark 232” (trade name); Arco Chem
(manufactured by ica1) 3 High-density polyethylene (product type “LB-742” (trade name); 80U, S, In
Industrial Chemica1) iron powder
20 4 Low density polyethylene (variety “NA-226” (trade name); 85U, S,
Industrial Chemica 1) Iron oxide 15 5 Polypropylene 85
Variety 8523. Vercules) Iron powder 15 6 300% dry weight 8571. Styrene/butadiene latex impregnated brushed cotton flannel fabric 8 oz (227 g) 75 (U dry weight) Iron oxide 15 As a counter, the thickness of the layer containing the plastic
Typically about 1,020 inches (0.05 crrL) to 0.060 inches (0.15 crfL). The thickness of the adhesive coating is typically about 0.003 inches (0.00
76 an) to 0.005 inch (0,013 CTL
).

Preferred compositions, which reduce the required heating time, have suitability for processing to meet the required properties of plastics, require less cost, and provide good performance for the shoe, contain 25 to 30% as the magnetic component. It has 35% iron oxide. This composition reduces power requirements and eliminates the need for relatively expensive induction heating equipment. The current most preferred formulation is as follows.

High-density polyethylene (density 0.958-0.962) (
Melt index 0.25~1.25) 4
2.5-functional tyrene/vinyl acetate copolymer (vinyl acetate 18-28%) (melt index 6-50) 25.
0Foote Mineral Company”
Magnetic iron oxides such as Magna float D”
32.5

[Brief explanation of drawings]

FIG. 1 is a perspective view of the shoe counter of the present invention, and FIG. 2 is a cross-sectional view of the counter of FIG. 1 taken along line 2--2. 10: Counter-shaped sheet 12 Niblastic layer
14: Adhesive layer patent applicant Bixby International Corporation

Claims (1)

[Claims] 1. A reinforcing material for shoes comprising a mixture of plastic resin and at least one magnetic material. 2. A reinforcing material according to claim 1, comprising a textile element. 3. The reinforcing material according to claim 1, wherein the resin is polyethylene. 4. The reinforcing material according to claim 1, wherein the resin is polypropylene. 5. The reinforcing material according to claim 1, wherein the magnetic material is iron particles. 6. The reinforcing material according to claim 5, wherein the magnetic material contains particles of iron oxide. 7. The reinforcing material according to claim 1, wherein the magnetic material is iron oxide particles. 8. A reinforcement according to claim 1, having an outer layer of adhesive, heat-activable at a temperature at which the adhesive becomes moldable into a core reinforcement. 9. The reinforcing material according to claim 1, wherein the resin is Surlyn.