INSOLE

Abstract

The invention relates to an insole (100) for shoes, in particular as a disposable product, having a top layer (200) that comprises a two-ply basic material and faces the foot, and a base layer (202) that is connected to said top layer (200) and faces the shoe, and having a foot surface (104) that faces the foot and an opposite Sole surface (102) that laces the shoe, wherein the top layer (200) and the base layer (202) consist of a staple-fibre nonwoven and bicomponent fibres and absorbent cellulose-based fibres and/or hydrophilic synthetic fibres are contained in the top layer and in the base layer, and wherein the insole has a combination comprising at least two different active-substance groups, the active-substance groups being selected from the group of antimicrobial active substance, odour absorbent and odour-masking substance, and both the base layer (202) and the top layer (200) being assigned at least one active-substance group.

Claims

1. An insole (100) for shoes, comprising a basic material containing at least two layers, the basic material comprising a top layer (200) facing the foot and a base layer (202) bonded thereto that faces the shoe, and wherein the top layer (200) has a foot surface facing the foot (104) and the base layer (202) has an opposite sole surface (102) that faces the shoe, and wherein the top layer (200) and the base layer (202) comprise a staple fiber nonwoven and bicomponent fibers, and absorbent cellulose-based fibers and/or hydrophilic synthetic fibers which are contained in the top layer and in the base layer, and wherein the insole further comprises a combination of at least two different active substances, the active substances being selected from the group consisting of antimicrobial active substances, odor-absorbing agents, odor-masking substances, and combinations thereof, and both the base layer (202) and top layer (200) each contain at least one of the active substance groups.

2. The insole (100) of claim 1, wherein, the base layer (202) and the top layer (200) differ in at least one property, selected from the group consisting of fiber composition, weight per unit area, thickness, density, and water retention capacity.

3. The insole (100) of claim 1, wherein the insole (100) has an infiltration time of at most 20 seconds.

4. The insole (100) of claim 1, wherein the top layer (200) and/or the base layer (202) has/have a water retention capacity of at least 1 g/g and at most 15 g/g.

5. The insole (100) of claim 1, wherein the base layer (202) and the top layer (200) are bonded by an embossed pattern (109).

6. The insole (100) of claim 1, wherein one of the at least two active substances is an odor-absorbing agent (206) which is provided on the sole surface (102).

7. The insole (100) of claim 1, wherein one of the at leas two active substances is an odor-masking substance (208) which is provided on the foot surface (104).

8. The insole (100) of claim 1, wherein one of the at least two active substances is an antimicrobial active substance (204, 210) which is provided on the foot surface (104) and/or in the top layer (200), and/or on the sole surface (102), and/or in the base layer (202).

9. The insole (100) of claim 1, wherein at least one of the at least two active substances is provided such that it does not penetrate the base layer (202) and/or the top layer (200), and wherein the active substance is provided in particle-bound and/or polymer-bound form on the sole (102), and/or on the foot surface (104) of the basic material.

10. The insole (100) of claim 1, wherein one of the at least two active substances is not provided in particle-bound and/or polymer-bound form on the sole (102), and/or foot surface (104) of the basic material, and is capable of diffusing into the interior of the respective layer.

11. The insole (100) of claim 1, wherein the at least two active substances is a combination of three different active substances.

12. The insole (100) of claim 1, wherein one of the at least two different active substances is arranged on one of the surfaces selected from the sole surface (102) and the foot surface (104), and the other of the at least two active substances is arranged on the other at the two surfaces, selected from the foot surface (104) or the sole surface (102).

13. The insole (100) of claim 1, wherein on the sole surface (102), a coating (112) is provided that imparts increased frictional force to the sole surface (102) compared to the uncoated sole surface (102).

14. The insole (100) of claim 13, wherein the coating (112) is not full-surface, but is composed of coating elements selected from the group consisting of point-shaped coating elements, line-shaped coating elements, sheet-shaped coating elements and combinations thereof.

15. The insole (100) of claim 13, wherein at least one of the at least two different active substances in the coating (112) is added to and/or bonded to said coating.

16. The insole (100) of claim 1, wherein one of the at least two different active substances is an odor-absorbing agent (206) which is selected from the group consisting of activated carbon, zeolite, starch, diatomaceous earth and combinations thereof.

17. The insole (100) of claim 1, wherein one of the at least two different active substances is an antimicrobial active substance (204, 210) which is selected from the group consisting of antimicrobial metals, polysaccharides, and combinations thereof.

18. The insole (100) of claim 1, wherein one of the at least two different active substances is an odor-masking substance (208) which comprises a microencapsulated perfume.

19. The insole (100) of claim 1, wherein the top layer (200) comprises 25-35 wt % bicomponent fibers, at least 20 wt %, hydrophilic synthetic fibers, and optionally, also up to 50 wt % cellulose-based fibers.

20. The insole (100) of claim 1, wherein the base layer (202) comprises 35-60 wt % bicomponent fibers at least 40 wt % cellulose-based fibers, and optionally, also up to 10 wt % synthetic fibers.

21. The insole (100) of claim 1, wherein one of the at least two different active substances is an antimicrobial active substance (204, 210) which is provided in a weight per unit area of 0.001-2 g/m.sup.2.

22. The insole (100) of claim 1, wherein one re the at least two different active substances is an odor-absorbing agent (206) which is provided in a weight per unit area of 0.2-30 g/m.sup.2.

23. The insole (100) of claim 1, wherein one of the at least two different active substances is an odor-masking substance (208) which is provided in a weight per unit area of 0.1-5 g/m.sup.2.

24. The insole (100) of claim 1, wherein the at least two different active substances are the active substance groups of antimicrobial active substances (204, 210) and odor-absorbing agents (206) which are introduced in a weight ratio of 1:2 to 1:500, and/or the active substances are antimicrobial active substances (204, 210) and odor-masking substances (208) which are introduced in a weight ratio of 1:0.5 to 1:150.

25. The insole (100) of claim 17, wherein the antimicrobial metal is silver and/or the polysaccharide is chitosan.

26. The insole (100) of claim 19, wherein the biocomponent fibers are polyester-based, and/or the hydrophilic synthetic fibers are polyester fibers, and/or the cellulose based fibers are viscose.

27. The insole (100) of claim 20, wherein the biocomponent fibers are polyester-based, and/or the cellulose-based fibers are cotton, and/or the synthetic fibers are polyester fibers.

Description

[0105] The invention is described in the following with reference to a drawing. The figures show the following:

[0106] FIG. 1: an insole according to the invention,

[0107] FIG. 2: an insole according to FIG. 1 with an additional coating on the sole surface,

[0108] FIG. 3a: a schematic section through the basic material of an insole according to the invention,

[0109] FIG. 3b: a schematic diagram of a section of a fiber layer with adhesion points of bicomponent fibers,

[0110] FIG. 4: diagrams a) to b) show enlarged sections of an insole according to the invention,

[0111] FIG. 5: diagrams a) to c) show enlarged sections of an insole according to the invention,

[0112] FIG. 6: a schematic diagram of the test device for measuring infiltration time.

[0113] FIG. 1 shows a top view of the sole surface of an insole according to the invention 100, wherein the sole surface 102 during use of the insole faces the interior of a shoe and the surface opposite the sole surface 102 faces the foot as a foot-side surface 104. The insole 100 is composed of a two-layer basic material, specifically with a top layer 200 facing the foot and a base layer 202 facing the shoe, as shown in FIG. 3a as a schematic section through the insole 100 according to FIG. 1. The top layer 200 and the base layer 202 are composed of a staple fiber nonwoven. The nonwoven material comprises bicomponent fibers in the top layer and the base layer, indicated by the reference number 150, and absorbent cellulose-based fibers and/or hydrophilic synthetic fibers, indicated by the reference number 152.

[0114] In both the top layer 200 and the base layer 202, the total weight of the respective layer preferably comprises at least 10 wt % bicomponent fibers, and an amount of 60 wt % is preferably not exceeded. With their low-melting-point component, preferably the sheath component, the bicomponent fibers contribute toward point-shaped bonding 160 of the fibers in the layers and between the layers, as shown schematically in FIG. 3b. The top layer and the base layer advantageously show a water absorption capacity of at least 2 g/g. The insole shows an infiltration time of at most 20 sec. The basic material is consolidated by being pre-calendered, i.e., passed between a heated calendar roller with protruding embossing projections and a counterpressure roller. In this manner, the surface structure 106 that can be seen in FIG. 1, in this case with point-shaped and rib-shaped embossing structures 109, is formed. The engraving depth achieved by means of the calendering, which is 0.7 mm in the present case, can, however, be set as desired by the person having ordinary skill in the art based on his or her technical expertise. In the embossed area, high-density embossed areas 109 are formed in addition to less dense areas 110. The percentage of the entire surface area accounted for by the high-density areas 109 is 5-15%.

[0115] The basic material of the insole has a base layer with a preferred basis weight of 200-300 g/m.sup.2 and a top layer with a preferred basis weight of 20-100 g/m.sup.2, and depending on the seasonal use of the insole, a higher weight per unit area of the top layer of 50-100 g/m.sup.2 can be favored for winter insoles and a lower weight per unit area of 20-50 g/m.sup.2 can be favored for summer insoles.

[0116] As shown in FIG. 2, a coating 112 of coating lines 114 is provided on the sole surface 102 of the insole 100 facing away from the sole of the foot and toward the inside of a shoe. This prevents sliding of the insole 100 inside a shoe. The coating lines 114 are polymer-based and preferably composed of EVA (ethylene vinyl acetate). The material preferably has a Shore A hardness of at least 30, preferably 60-80, and preferably at most 90. The coating is applied by means of an engraving process, wherein the insole 100 is passed between a gravure roller and a counter-roller. The width of the coating lines is preferably 0.5-0.7 mm. The height of the coating lines is preferably 0.2-0.3 mm so that application of the coating pattern will not result in any unpleasant haptic effects on the foot.

[0117] The coating shown in FIG. 2 has a plurality of individual patterns 120 that are formed by the coating lines 114. In the case shown, each individual pattern 120 is preferably formed by pattern groups 124, wherein the pattern groups are composed of at least three pattern elements 126, here concentrically arranged circles, and no coating mass is applied between the individual circles of each pattern group forming an individual pattern, thus leaving an uncoated area 116 therein. In this manner, by means of the coating lines 114, a total coverage ratio on the sole surface of approx. 20-25% is achieved. This relatively low coverage ratio of the coating has no substantial effect on the further attributed and desired properties of the basic material of the insole, such as for example air permeability and/or breathing activity.

[0118] The dynamic friction coefficient of the coated sole surface, measured in accordance with ASTM D 1894-01, is between 0.8 and 1.4.

[0119] In FIG. 4 diagrams a) and b) and FIG. 5 diagrams a) to c), a section is shown through an insole according to the invention 100 comprising a basic material with two layers, specifically a top layer 200 and a base layer 202. The base layer 202 faces a shoe and comprises the sole surface 102. The top layer 200 faces a foot and comprises the foot surface 104. It can be seen in the diagrams that a coating 112 is provided on the sole surface that can be configured analogously to the coating shown in FIG. 2.

[0120] In the insole 100, active substances for preventing or alleviating odor are assigned to the base layer 202, in particular the sole surface 102, and to the top layer 200, in particular the foot surface 104 respectively. These active substances are selected from the active substance groups of antimicrobial active substances, odor-absorbing agents, and odor-masking substances.

[0121] Examples for the arrangement of two active substance groups are shown in FIGS. 4a and 4b.

[0122] In the design of FIG. 4a, an antimicrobial active substance 204, in this case not in a polymer- or particle-bound configuration, is applied to the foot surface 104 and partially also to the top layer 202, and on the sole surface 102, an odor-absorbing agent 206 is bound into the coating 112. In the design of FIG. 4b, an odor-masking substance 208 is provided on the foot surface and an antimicrobial active substance 210 is provided in the coating 112 on the sole side 102 as active substances.

[0123] Examples of the arrangement of the three active substance groups are shown in FIGS. 5a-5b.

[0124] In all of the configurations in FIG. 5a) to c), the active substances are distributed in such a way that the odor-absorbing agent 206 is provided in the coating 112 on the sole surface 102, wherein a highly-porous, fine granular carbon such as activated carbon is preferably used. The odor-absorbing agent is thus in direct contact with the shoe and odors present therein. In this manner, the odors are directly and rapidly absorbed.

[0125] In all three configurations of FIG. 5 as well, the odor-masking substance is provided on the foot surface in the form of microencapsulated fragrances that contain perfume oils, said fragrances being indicated by the reference number 208. The fragrances are released in a dosed and controlled manner by pressure and shearing on use of the insole, which causes the capsules to be destroyed.

[0126] In FIG. 5a), a polysaccharide, indicated here in particular by the reference number 204, is used as an antimicrobial active substance, specifically both on the foot surface 104 and in the nonwoven material of the top layer 200, and partially in the nonwoven material of the base layer 202. This active substance serves to control the odor of fresh foot perspiration in that its antimicrobial activity inhibits the growth of bacteria.

[0127] A similar design is shown in FIG. 5b), wherein the antimicrobial active substance here is in the form of silver particles 210 on the foot surface 104. The silver particles are preferably composed of silver bound to a glass-ceramic matrix.

[0128] An alternative design is shown in FIG. 5c), wherein the same silver particles 210 as in FIG. 5b) and the odor-absorbing agent 206 are present in the coating 112 on the sole surface 102. In this arrangement, the antimicrobial active substance 210 can serve to control bacterial growth on the sole side, and thus also to control odor in the shoe. New perspiration and the formation of new odors are prevented by the fragrances contained in the odor-masking substances 208 and the perspiration-absorbing action of the top layer 200 and base layer 202.

[0129] A measurable antimicrobial action can be achieved by selecting an antimicrobial active substance from the active substance groups and using it in the insole. As examples of this, the embodiments of the insole according to the diagram of FIG. 5a as example 1 and the diagram of FIG. 5b as example 2 are described, and the antimicrobial action thereof is measured.

[0130] The insole has a basic material composed of a base layer of 200-300 g/m.sup.2 and a top layer of 50-100 g/m.sup.2. The base layer has a fiber composition of 35-60 wt % PES bicomponent fibers and further a mixture of hydrophilic synthetic PES fibers and absorbent cellulosic fibers; the top layer comprises 25-35 wt % of PES bicomponent fibers and further hydrophilic synthetic PES fibers. The top layer is laminated onto the base layer by means of pressure, temperature, and embossing.

[0131] In example 1, chitosan is applied to the foot surface as an antimicrobial active substance together with a microencapsulated perfume oil as an odor-masking substance. The amount of chitosan used is 0.05-0.06 wt %, and the amount of the encapsulated perfume oil used is 0.5-0.65 wt %, based respectively on the total weight of the insole. As an odor-absorbing agent, activated carbon is applied to the sole side in a line-shaped polymer coating comprising a content of 1-2% based on the total weight of the insole.

[0132] In example 2, as a variant of example 1, particle-bound silver with a content of 0.003-0.005 wt % based on the total weight of the insole is applied to the foot surface as an antimicrobial active substance.

[0133] The antimicrobial action is measured in accordance with DIN EN ISO 20743A:2013-12. Staphylococcus epidermidis ATCC 14990 is used as a test microbe. The test is conducted based on the absorption method, and the plate count method is used for quantitative measurement. Changes are made such that NaCl 0.9%+0.05% Tween 80 is used as an inoculation medium and NaCl 0.9%+0.20% Tween 80 is used as an elution medium. Microbial growth over 18 h on the sample is calculated compared to the control or reference material according to the following formula:

A=(log.sub.10 C.sub.tlog.sub.10 C.sub.0)(log.sub.10 T.sub.tlog.sub.10 T.sub.0).

[0134] where C denotes the control fabric. T denotes the test sample. log.sub.10 C.sub.t or log.sub.10 T.sub.t=general logarithm of the arithmetic mean for the bacterial count after incubation for 18 h in control fabric C or test sample T.

[0135] log.sub.10 C.sub.0 or log.sub.10 T.sub.0=logarithm of the arithmetic mean for the bacterial count immediately after inoculation in control fabric C or test sample T.

[0136] A simplified calculation is taken as a basis, with the modification of equating microbial growth log.sub.10 C.sub.0 and log.sub.10 T.sub.0.

[0137] For both example 1 and example 2, strong antibacterial activity was detected, i.e. with a microbial reduction3 log CFU.

[0138] Such an insole provides good tread comfort, combined with a feeling of foot dryness and reduced odor formation.