PT108709A - CORK SOLES FOR FOOTWEAR AND RESPECTIVE MANUFACTURING PROCESS - Google Patents

Abstract

The present disclosure relates to soles for footwear, in particular soles for footwear which comprise a mixture of 20-40% (w / w) of cork with a granulometry of 0.5-3 mm and 60-80% (w / w ) OF A POLYMERIC AND AGGLOMERANT MATERIAL. THIS DISCLOSURE STILL REFERS TO THE RESPECTIVE PROCESS OF MANUFACTURING THE REFERRED SOLES FOR FOOTWEAR.

Description

DESCRIPTION

CORK SOLES FOR FOOTWEAR AND RESPECT

MANUFACTURING

TECHNICAL FIELD The present disclosure relates to soles for footwear, in particular soles for footwear which comprise a mixture of cork and polymer material and its manufacturing process.

BACKGROUND ART Documents relating to the use of cork-based products, namely insoles, are known in the prior art. The cork is used for this purpose because it is a comfortable material for the user's foot and that easily molds and adapts to it, thus causing no discomfort to its user.

[0003] However, the use of cork as an integral part of soles for footwear is not known. The use of cork for this purpose allows to recycle cork waste, that is, to use cork waste from other industries that would otherwise be a waste.

[0004] The reason why cork waste is not used to date as sole for footwear is that cork alone does not have the necessary characteristics, namely abrasion resistance, breakage , flexion. Accordingly, the present disclosure discloses a sole that uses cork conjugated binders.

These facts are described in order to illustrate the technical problem solved by the embodiments of the present document.

Overview [0006] Cork is a natural, lightweight, waterproof product with thermal and abrasion resistant properties. Cork is still a recyclable, renewable, biodegradable and sustainable product.

The incorporation of cork into products, in particular soles for footwear is an option that favors the preservation of the environment. At the same time, the incorporation of cork in soles for footwear also allows to absorb the impacts of the user, cushion of shocks, presents resistance to the skid, durability, greater superficial friction. In terms of aesthetic effects, it provides a pleasant aesthetic effect.

[0008] However, cork alone does not have attributes and skills to be used as sole for footwear. Thus, it was extremely challenging to obtain a formulation for cork-formed shoe soles and the respective manufacturing process in which the soles had the desired mechanical properties at break and flexibility.

The present disclosure is therefore based on the disclosure of a strategy which allows to combine the use of cork as an integral part of footwear soles together with other material, in particular polymeric material. This mixture, cork and polymeric material, allows to obtain a shoe sole with resistance, hardness, flexibility and friendly to the environment. So far, this combination and its manufacturing process were non-existent.

The present application describes a sole for footwear comprising the following elements: • 20-40% (w / w) cork with a particle size of 0.5-3 mm, preferably with a particle size of 2-3 mm ; • 60-80% (w / w) of a polymeric material and binder selected from a list consisting of: natural rubber, butadiene styrene rubber, nitrile butadiene rubber, ethyl vinyl acetate rubber and mixtures thereof.

The particle size of cork - cork particles - can be measured by many methods known for example by sieves and sieves, in particular according to ISO 2030.

The sole described in the present disclosure allows the use of cork in large quantities without compromising the mechanical performance of the sole, namely the flexibility at 20 ° C of the sole is 7, this value being the value calculated by the ASTM standard F147 and corresponds to the mandrel number; the hardness is between 50-90 Shore A and this value is calculated using a Shore durometer; and the minimum tensile strength is 0.9 to 3.5 MPa, this value being calculated by ASTM F 152.

For best results in one embodiment, the shoe sole may comprise the following elements 40% (w / w) of cork and 60% (w / w) of the polymeric material and binder.

For best results in one embodiment, the sole for footwear is comprised of cork and the percentage of cork varies between 20-40% (w / w), preferably between 22-38% (w / w), over preferably between 25-35% (w / w).

For best results in one embodiment, the sole may have a density at 20Â ° C ranging from 480-1250 kg / m 3, preferably 600-740 kg / m 3.

For best results in one embodiment, the sole may comprise a final thickness between 8-12 mm, preferably between 8.5-11.5 mm, more preferably between 9.5-11 mm, over preferably 9-11 mm.

For best results in one embodiment, the sole may further comprise a film for coating a part of the sole, in particular the upper part of the sole which is in contact with a foot of the wearer.

In one embodiment, the sole may also comprise a set of additives, for example, dyes, fragrances, emulsifiers, stabilizers, waterproofing agents, varnishes, or mixtures thereof.

In one embodiment, the sole described may be a sole for slippers, flip-flop slippers, espadrilles, sabrins, shoes or boots.

The present application also describes a process for producing the sole described above. This process comprises the following steps: uniformly mixing the cork with a particle size of 2-3 mm with a polymeric material and binder selected from the following list: natural rubber, styrene butadiene rubber, nitrile butadiene rubber, ethyl vinyl acetate rubber and mixtures thereof in a ratio of about 1: 1; 1: 2; 1: 3, 1: 4; forming a block with the obtained mixture; vulcanizing the block; unmold the block; stabilize the block; cut the block to the desired thickness and shape.

In one embodiment, the method may further comprise a step of placing plastic strips in the sole.

In one embodiment, the method further comprises the predefined image embossing step in the sole.

Throughout the description and claims the word "comprises" and variations of the word, do not intend to exclude other technical features, additives, components, or steps. Additional objects, advantages and features of the disclosure will become apparent to those skilled in the art upon examination of the disclosure or may be learned by the practice of disclosure. The following examples and figures are provided as an illustration, and are not intended to be limiting on the present disclosure. Further, the present disclosure encompasses all possible combinations of particular or preferred embodiments described herein.

BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding of the solution, the following figures are attached, which represent preferred embodiments of the solution which, however, are not intended to limit the object of the present application.

Figure 1: Representing a preferred embodiment of the present solution wherein: 1 - represents the sole of footwear, in particular, a sole of a flip-flop slipper; 2 - represents a strip of plastic.

Detailed description The described shoe sole comprises a cork granulate and a polymeric material and binder, in particular rubber which allows to obtain cork soles with improved properties.

The connection of the cork with the polymeric material and binder is made in a proportion of 20% - 40% (w / w) of cork to 60% - 80% (w / w) of the polymeric material and binder, minimum percentage of cork is 20% (w / w) and the maximum percentage is 40% (w / w), while the minimum percentage of polymeric material and binder is 60% (w / w) and the maximum percentage of 80 % (w / w).

The polymeric material and binder to be used should exhibit good abrasion resistance and flexibility. This material may be selected from the following list: styrene butadiene rubber, natural rubber, nitrile butadiene rubber, ethyl vinyl acetate rubber or mixtures thereof.

The final products that the sole for footwear in their composition may be, for example, slippers, flip-flops, espadrilles, sabrins, shoes and / or boots.

One embodiment of the present solution is based on the following steps for obtaining a sole for footwear, in particular for flip-flops: • joining the cork and the polymeric material and binder, preferably adding and calendering ; • vulcanize the block at 160 ° C for 8h - 12h; • unmold the block after 12h - 48h; • stabilize the block produced and allow the solidification thereof; • laminating the block of the desired thickness in order to obtain cork slabs of the desired final thickness, for example 11 mm; • cutting the cork boards in the desired format, for example in slipper shape, with steel cutting molds through a press or cutting machine; • print of the slipper, obtained through the technique of serigraphy; • place the plastic strips.

The rubber that may be used may be selected from the following list: styrene butadiene rubber, natural rubber, nitrile butadiene rubber, ethyl vinyl acetate rubber or mixtures thereof.

One embodiment of the present disclosure in which obtaining a sole for footwear, whether for an espadrille, the block will be laminated so as to have a final thickness of 10 mm while the shoe is a sabrina, the block will be laminated so that its final thickness is 8 mm.

Although in the present disclosure only particular embodiments of the solution have been represented and described, the person skilled in the art will know how to make modifications and replace technical characteristics with other equivalent ones, depending on the requirements of each situation, without departing from the scope of protection defined by claims.

The embodiments shown are combinable with each other. The following claims further define preferred embodiments. July 20, 2016

Claims (12)

1. Sole for footwear comprising the following elements: 20 - 40% (w / w) of cork with a particle size of 0.5-3 mm, preferably with a particle size of 2-3 mm; 60-80% (w / w) of a polymeric material and binder selected from a list consisting of: natural rubber, butadiene styrene rubber, nitrile butadiene rubber, ethyl vinyl acetate rubber and mixtures thereof. Sole as claimed in the preceding claim comprising: 25-40% (w / w) of cork; 60-75% (w / w) of the polymeric material and binder. Sole according to the preceding claim comprising the following elements 40% (w / w) of cork; 60% (w / w) of the polymeric material and binder. Sole according to the preceding claims in which the cork varies from 22-38% (w / w), more preferably from 25-35% (w / w). A sole according to the preceding claims wherein the density at 20Â ° C of the sole varies between 480-1250 kg / m 3, preferably 600-740 kg / m 3. A sole according to the preceding claims comprising a final thickness between 8-12 mm, preferably between 8.5-11.5 mm, more preferably between 9-11 mm, more preferably 9.5-11 mm . A sole according to the preceding claims further comprising a film for coating a part of the sole, in particular the upper part of the sole which is in contact with a foot of a wearer. A sole according to the preceding claims further comprising a set of additives selected from the following list: colorants, fragrances, emulsifiers, stabilizers, waterproofing agents, varnishes, or mixtures thereof. Footwear comprising the sole according to any one of the preceding claims, in particular slippers, flip-flop slippers, espadrilles, sabrins, shoes or boots. A process for producing the sole described in any one of claims 1-8 which comprises the following steps: uniformly mixing cork particles with a particle size between 0.5-3 mm, preferably with a particle size of 2-3 mm ; with a polymeric material and binder selected from the following list: natural rubber, styrene butadiene rubber, nitrile butadiene rubber, ethyl vinyl acetate rubber and mixtures thereof; in a ratio of 1: 1 to 1: 4; preferably 1: 2-1: 3; forming a block with the obtained mixture; stabilize the block produced; cut the block to the desired thickness and shape. A method according to the preceding claim further comprising a step of placing plastic strips in the sole. A process according to claims 10-11 further comprising a step of stamping images on the sole. July 20, 2016