JPH0444522B2 - - Google Patents

Description

[Detailed description of the invention]

<Industrial Application Field> The present invention relates to shoe insole materials such as flat insoles and cup insoles. <Prior art> Shoe insole materials are intended to provide wear resistance, elasticity (shock absorption), and sweat absorption to the insole, and are made of synthetic leather, leather, leather, and woven fabric, such as flat insoles. There are known types of insoles, such as those affixed to an insole material, or those in which a surface cloth is affixed to an elastic sheet, such as a cup insole. However, since these insole materials are made by cutting each material and pasting them together, the number of materials is large and the processing is complicated.
Moreover, these insole materials have almost no function in terms of absorbing sweat, or the absorbed sweat flows back to the surface in a very short period of time and wets the surface, making it difficult to feel stuffy when worn. This results in unpleasant sensations such as cold and cold sensations, and the growth of bacteria causes athlete's foot and foul odors. The present inventors have developed a shoe insole material that is easy to manufacture and easy to handle, by mixing various main fibers with heat-adhesive fibers, heat-compression molding the entangled mixture, and making the main fibers into heat-adhesive fibers. A method using sheets bonded with fibers was proposed (Japanese Patent Application No. 59-68585). <Problems to be Solved by the Invention> The present invention provides an insole material using the above-mentioned heat-compression molded sheet, which has good absorbency for sweat, etc., and also maintains the surface in a dry state. The aim is to provide something that is hygienic and comfortable to wear. <Means for Solving the Problems> The present invention consists of a compression-molded product of a fiber entanglement in which main fibers including hydrophilic fibers are bonded by heat-adhesive fibers, and has a moisture permeability of 1000 to 6000 g/m ² / A shoe insole material characterized by being a moisture permeable sheet having a compressive elastic modulus of 70% or more and a water absorption rate of 100% or more for 24 hours, with a hydrophobic thin layer integrated on the surface or surface layer thereof. It is. First, the moisture-permeable sheet, which is the main component of the shoe insole material of the present invention, is thermally bonded to the main fibers, including various natural fibers, vinylon, nylon, or hydrophobic fibers with relatively good water absorption properties, whose surfaces have been made hydrophilic. A cotton-like body or a web laminate mixed with adhesive fibers is preferably entangled and densified by needle punching or fluid entanglement method, and then heated and compression molded to melt or soften the heat-adhesive fibers and create bonds between the main fibers. Manufactured by gluing. The hydrophilic fibers (including hydrophilic fibers) used as the main fibers have a water absorption length of 60
mm/hr or more, and is appropriately mixed with other main fibers within the range where the water absorption rate as a sheet is 100% or more. Particularly preferred as such hydrophilic fibers are those that are essentially hydrophobic;
For example, at least the surface has a fine structure or the surface is coated with a hydrophilic resin, etc., and the water absorption length as a fiber is 60 mm/hr or more. The product can be dry. The thermoadhesive fibers used have a softening point or melting point lower than that of the main fibers and have the property of adhering between the main fibers when the sheet is thermally compressed. Preferably, it softens or melts at 100 to 130°C and exhibits an adhesive function. Such fibers include fibers made of or containing polyolefin synthetic resins, copolyester resins, etc., and low-oriented fibers such as unstretched polyester fibers. Specifically, polyethylene, polystyrene, etc. Core-sheath type, bimetal type composite fibers, undrawn polyester yarns, etc. of polyethylene terephthalate and copolyester are known and can be effectively used in the present invention. The mixing ratio of heat-adhesive fibers to the main fibers is
In order to give the sheet sufficient hardness, shape retention, recovery from deformation, and water absorption,
It is effective to set the content to 50 to 150% by weight. In addition,
As a sheet, it has an apparent density difference in the thickness direction,
Wearability can be improved by making the front side soft and the back side hard. Such a moisture permeable sheet in the present invention can be used as a shoe insole material with a moisture permeability of 1000 to 6000 g/m ² /
For 24 hours, it is desirable that the compression modulus is 70% or more and the water absorption rate as a sheet is 100% or more. If the moisture permeability is less than 1000g/m ² /24hr, the ventilation effect due to the pumping action (repetitive compression-relaxation action) when worn as an insole material will not be sufficient, and sufficient sweat absorption and perspiration properties will not be obtained. . In addition, the moisture permeability is 6000g/
If m ² /24 hr or more, the retention of sweat and the like within the sheet is poor, and even with the structure of the present invention, moisture absorbed into the sheet due to the pumping action flows back to the surface side, which is undesirable. In addition, when the compressive modulus is 70% or less,
The cushioning properties when worn are insufficient, the product tends to sag, and the pumping effect for sweat absorption is poor. Furthermore, if the water absorption rate of the sheet is less than 100%, the sweat absorption property will not be sufficient and the water absorbed by pumping will flow back to the surface, resulting in an undesirable product. Such sheets are compression molded to have an average apparent density of 0.2 to 0.6 g/cm ³ , are mixed with 50 to 150% by weight of heat-adhesive fibers, and are mainly composed of fibers with a water absorption length of 60 mm/hr or more. It can be obtained when it contains more than 50% by weight. When giving a difference in apparent density between the front side and the back side of the sheet, the front side should be 0.4 g/cm ³ or less, and the back side should be 0.1 g/cm ³ or more, preferably 0.3 g/cm ³
It is preferable to make it larger. In addition, in order to further increase the hardness of the insole and prevent the absorbed moisture from flowing back, we layered a hydrophobic film inside the sheet and integrated it with the fiber layer by needle punching. It is effective to partially melt and form a porous film layer within the sheet. In the present invention, a hydrophobic thin layer is integrated on the surface or surface layer of the compression-molded sheet. One of the hydrophobic thin layers is a metal thin layer formed on the surface of the sheet by metal plating, vapor deposition, or sputtering. This metal layer should be formed to such an extent that it closes the spaces between the fibers of the sheet and does not impair air permeability. Further, one of the other hydrophobic layers is formed as a breathable layer of hydrophobic fibers having a water content of 1% or less. As this layer, a mesh-like knitted fabric, a web, or a non-woven fabric is used. These layers are integrated with the sheet surface of the main body by adhesive or the like, or by intertwining means such as needle punching. Furthermore, in the present invention, the surface side is embossed to improve not only the feeling of wearing but also the anti-slip effect and sweat absorption effect. <Functions and Effects> According to the present invention, water vapor sweated when wearing shoes is first transferred from the surface of the insole material to the non-woven fabric part by compression pressure (pumping effect) when walking. Water is sucked into the inner layer of the insole from the back of the foot along the gradient of water vapor partial pressure between the surface of the insole (between the foot) and the back of the insole (between the insole). Here, under the effect of temperature cooling, the water vapor reaches a saturation point and condenses between the fibers. The condensed moisture further permeates into the insole material due to the cushion pressure (pumping effect) from the surface of the insole material or the capillary action of the hydrophilic fibers that make up the sheet.
Dispersed and adsorbed. Furthermore, in the present invention, since there is a hydrophobic layer on the surface or surface layer, moisture absorbed into the insole material body does not stay on the surface and does not easily flow back. The side that comes in contact with the shoes is always kept dry, eliminates stuffiness on the feet, is comfortable to wear, and does not cause sports problems such as so-called blisters.
Further, according to the configuration of the present invention, when not worn, it is relatively easy to dry, and exhibits the effect of preventing the generation of bacteria and bad odor. Of course, the insole material of the present invention is easy to manufacture, can be used immediately by simply cutting into the required shape, and has good workability. Here, the moisture content, moisture permeability, compressive modulus of fiber, water absorption length of fiber, and water absorption rate of sheet are measured as follows. (1) Moisture content: According to JIS L-1015 (2) Moisture permeability: According to JIS Z-0208 Cupp method (3) Compressive elastic modulus: Compressive elastic modulus (%) calculated using the following formula = T ₀ ′ − T ₁ / T ₀ −T ₁ ×100 However, T ₀ ; Thickness at initial load (240g/cm ² × 1 minute) T ₁ ; Thickness at final load (4Kg/cm ² × 1 minute) T ₀ ′; Initial load Thickness when returned to (4) Water absorption length of fiber; Glass pipe method 6mmφ×150
0.75 g of cotton (after oil washing) is evenly packed in a glass tube of 1.0 mm in diameter and the bottom is immersed vertically in colored water, and the water absorption length is measured after 1 hour (5) Water absorption rate of the sheet; Water absorption rate (%) of the sheet cut into 7.5 x 7.5 cm) and immersed in 20℃ water for a certain period of time using the following formula:
Weight after soaking - Weight before soaking / Weight before soaking x 100 Example 1 Hollow polyester fiber 12d x 51mm with a water absorption length of 90mm/hr and having a hydrophilic resin mainly composed of ester resin on the surface as the main fiber, adhesive properties As a fiber, polyethylene/polyester sea-island fiber (70/
30) 4d x 51mm mixed cotton at a ratio of 20/80, fabric weight 400
A wet with a weight of 200 g/m ² was used as the web for the back side, and a wep with a basis weight of 200 g/m ² made by blending the same main fiber and the same adhesive fiber in a ratio of 80/20 was used as the web for the front side. When spinning the front side web from the card, it was placed on a polyethylene film (50 μm) on a lattice and pre-punched, and after reversing, the back side web was spun from the card and pre-punched. Next, this punched nonwoven fabric was placed on a surface layer knitted fabric made of fibers with a moisture content of 0.5%, and a finishing punch (100%
After ^that , hot air treatment at 140° C. for 1 minute (first stage uniform heat treatment) was performed to form a sheet.
Next, the sheet is heated on both sides with infrared rays (non-uniform heat treatment with a back surface temperature of 150°C and a front side surface temperature of 120°C), and the mold temperature on the back side is 70°C and the mold temperature on the front side.
Pressing was performed using a drawing die at 20°C (cold press). The pressing pressure at this time was 0.4 kg/cm ² and the pressing time was 30 seconds. The sheet thus obtained has the physical properties shown in Table 1, and the cup insole made from it has felt-like elasticity on the front side and firm shape retention on the back side core. It had good sweat absorption (water absorption), no backflow of absorbed water was observed, and the surface was dry to the touch. Comparative Example 1 A cup insole similar to that in Example was manufactured using polyester fiber (water absorption length 15 mm/hr) as the main fiber. As shown in Table 1, this material had a low water absorption rate as an insole material, became saturated with water in a short period of time, and the absorbed water flowed back, making it impossible to obtain a dry feeling on the surface. Comparative Example 2 In Example 1, a cup insole was manufactured without integrating the polyester fiber knitted fabric for the surface material. After wearing this product, the dry feel of the surface was lost within a short time, and the absorbed water flowed back. Example 2 The pre-punched nonwoven fabric obtained in Example 1 was finished punched (100 pieces/cm ² ) as it was, rolled up into a roll, and then sputtered with nickel metal powder on the low-density surface area. Due to coating thickness
After forming a metal film layer of 400 Å, hot air treatment (uniform heat treatment) was performed under the same conditions as in Example 1, followed by press processing using a mold preheated by infrared rays (coalt press).
I did this and got a cup insole. The cup insole thus obtained had the physical properties shown in Table 1, and the back core had firm shape retention. Example 3 A surface material nonwoven fabric (fabric weight 120 g/m ² ) made of polyester fibers with a moisture content of 0.5% was placed on the pre-punched nonwoven fabric obtained in Example 1, and finishing punches (100 pieces/cm ² ) were performed. After that, hot air treatment (uniform heat treatment) at 140°C for 1 minute was performed, and then, before cooling, calender pressing was performed at a temperature of 20°C on the front side and a temperature of 70°C on the back side (embossing roll on the front side, flat roll on the back side). . The flat insole thus obtained is as shown in Table 1. Example 4 In Example 1, a sheet was prepared in which no polyethylene film (thickness: 50 μm) was inserted between the front and back webs, and it was molded under the same conditions as in Example 1 to obtain a cup insole. The front side of the cup insole had felt-like elasticity, and the back side core had firm rigidity. As a result of a shoe-wearing test, the time for reflux of absorbed water (wet bag detection time) was slightly shorter (400 minutes) than when inserting a film (more than 480 minutes), but compared to commercially available products with conventional technology. , the dryness of the surface was sufficiently maintained. Comparative Examples 3 and 4 In Example 1, finish punching was performed without placing the knitted fabric for the surface thin layer on the pre-punched nonwoven fabric in advance, and after forming a sheet under the same conditions, the water content was reduced by polyester hot melt nonwoven fabric on the surface side. 0.5
A knitted fabric for the surface thin layer consisting of 30% fiber was laminated and integrated. The cup insole obtained in this way prevents moisture absorption due to the influence of the adhesive, resulting in poor moisture permeability.
650g/m ² /24Hr, and as a result of the shoe wear test, the wet bag detection time was significantly shortened (240 minutes).On the other hand, in Example 1, the composition ratio of the main fiber and adhesive fiber of the back side web was Make a sheet (80/20) the same as that of the side web,
A cup insole was made under the same conditions. The performance of the cup insole obtained in this way is 7300% moisture permeability.
g/m ² /24Hr, and compression elastic modulus was 63%. As a result of the shoe wearing test, the wet bag detection time was 190 minutes, and the moisture permeability effect was significantly reduced, resulting in discomfort when worn.

【table】

【table】

Claims (1)

[Claims] 1 Composed of a compression-molded product of a fiber entanglement in which main fibers including hydrophilic fibers are bonded by heat-adhesive fibers, and has a moisture permeability of 1000 to 6000 g/m ² /24 hr and a compression modulus of 70. % or more and has a water absorption rate of 100% or more, and has a hydrophobic thin layer integrated on its surface or surface layer. 2. Claim 1 characterized in that the main fibers include fibers with a water absorption length of 60 mm/hr or more.
Shoe insole materials as described in section. 3 The main fiber has a moisture content of 1% or less, its surface has been treated to make it hydrophilic, and the water absorption length is 60%.
The shoe insole material according to claim 2, which contains fibers having a density of mm/hr or more. 4. The shoe insole material according to claim 1, 2 or 3, wherein the hydrophobic thin layer on the surface is a thin metal layer having air permeability. 5. The shoe insole material according to claim 1, 2, or 3, wherein the hydrophobic thin layer in the surface layer is a breathable fiber layer made of fibers with a moisture content of 1% or less. 6. The shoe insole material according to claim 5, wherein the breathable fiber layer is made of a mesh-like knitted fabric. 7. The shoe insole material according to claim 5, wherein the breathable fiber layer is made of web or nonwoven fabric. 8. The shoe insole material according to any one of claims 1 to 7, which has an embossed surface. 9 Claims 1 to 8 consisting of a moisture permeable sheet whose back side has a higher apparent density than the front side.
The shoe insole material according to any one of paragraphs. 10. The shoe insole material according to any one of claims 1 to 9, wherein a porous film is integrated inside the sheet.