WO2006034807A1

WO2006034807A1 - Ecological shoe

Info

Publication number: WO2006034807A1
Application number: PCT/EP2005/010189
Authority: WO
Inventors: Frascara Giuseppe Gazzoni
Original assignee: Gazzoni Ecologia S.P.A.
Priority date: 2004-09-27
Filing date: 2005-09-21
Publication date: 2006-04-06

Abstract

Recyclable ecological shoe without materials of animal origin (such as leather and hides) and containing a large quantity of recycled materials. This shoe comprises an outsole weighing not more than 60 % with respect to the overall weight of the shoe, essentially comprising an elastomer material comprising from 10 % by weight to 60 % by weight of a recycled elastomer material and having a high abrasion resistance, and an upper which includes a synthetic material comprising from 20 % by weight to 60 % by weight of a non-woven fabric (NWF) formed from at least one synthetic fibre and impregnated with at least one polyurethane resin in a quantity from 40 % by weight to 80 % by weight.

Description

ECOLOGICAL SHOE

This invention relates to a recyclable ecological shoe without materials of animal origin (such as leather and hides) and containing a large quantity of recycled materials.

It is known that the manufacture of shoes, in particular high quality slioes, generally requires the use of materials of animal origin such as leather and hides, which have optitimm properties in terms of flexibility, breathability and softness, as well as highly prized aesthetic properties, such as to render them particularly suitable for the manufacture of the visible parts of the shoe , such as the upper and the inner lining. However, from an ecological point of view the use of materials of animal origin gives rise to many problems, mainly associated with the process of tanning the hides, which, requires the disposal of substantial quantities of highly polluting chemical products, including chromium salts, chlorides and sulphates. Also, such materials cannot be used for recycling purposes once tb_e shoe has reached the end of its life.

International patent application WO 99/29201 describes a shoe comprising materials of natural origin, not obtained from petroleum derivatives, which would make the shoe biodegradable and recyclable at the end of its life. In particular a shoe which comprises a recycled natural rubber outsole to which a cardboard midsole coated with a layer of latex foam is described. A leather insole obtained using vegetable tanning and internal reinforcing members of recycled textile material are applied to the midsole. The upper comprises vegetable tanned leather, as does the inner lining of the shoe. The padding is obtained from latex foam, while the eyes and hooks are of metal material not containing nickel and lead.

Although vegetable tanning provides leather and hides with good aesthetic properties, the environmental impact of the manufacturing process nevertheless remains high, above all because of the need to dispose of enormous quantities of tannins, which are commonly used in this type of tanning.

The Applicant faced the problem of manufacturing ecological shoes, that is shoes having a low environmental impact which can be recycled at the end of their lives, without using materials of animal origin (i.e. leather and hides obtained by chemical or vegetable tanning) , which would have optimum aesthetic properties, durability and comfort, particularly in terms of lightness, softness and flexibility. In tackling this problem the Applicant did not consider materials of natural origin but rather synthetic materials having a reduced environmental impact, that is having a high content of recycled raw materials, so as to ensure that the finished product would nevertheless have the abovementioned aesthetic properties, comfort and durability. In particular, as far as the outsole is concerned, the Applicant considered to be necessary to reduce the weight of the outsole so as to ensure lightness and flexibility for the shoe, at the same time introducing a significant quantity of recycled elastomer material into the outsole without, however, compromising the mechanical properties of an outsole having such a reduced weight.

In the context of this description and the claims, by a "recycled" material is meant a material obtained from:

(i) post-consumption products (i.e. those which have reached the end of their lives) , (ii) waste finished

(or semi-finished) products, (iii) offcuts from the manufacture of semi-finished products, (iv) materials declassed to second choice, or mixtures thereof. The Applicant has found that the abovementioned problem can be solved by manufacturing a shoe which combines an outsole having a weight of not more than 60% with respect to the overall weight of the shoe, essentially comprising an elastomer material comprising from 10% by weight to 60% by weight of a recycled elastomer material and having a high abrasion resistance, with an upper which includes a synthetic material comprising from 20% by weight to 60% by weight of a non-woven fabric (NWF) formed from at least one synthetic fibre and impregnated with at least one polyurethane resin in a quantity from 40% by weight to 80% by weight.

In a first aspect this invention therefore relates to a shoe comprising: an outsole, an upper associated with the outsole, wherein: the outsole essentially comprises an elastomer material comprising from 10% to 60% by weight, preferably from 20% to 50% by weight, with respect to the overall weight of the outsole, of a recycled elastomer material, the said outsole having a weight of not more than 60%, preferably from 20% to 50%, and even more preferably from 25% to 40%, with respect to the overall weight of the shoe, and an abrasion resistance of not more than 250 mm³, preferably from 100 mm³ to 200 mm³

(measured in accordance with standard EN 12770) ; the upper comprises at least one synthetic material comprising from 20% by weight to 60% by weight, preferably from 30% by weight to 50% by weight, of a non-woven fabric (NWF) formed from at least one synthetic fibre, from 40% by weight to 80% by weight, preferably from 50% by weight to 70% by weight, of at least one polyurethane resin (PU) . The percentages by weight of the synthetic material components are expressed with respect to the overall weight of the synthetic material. Preferably the PU resin comprises at least 5% by- weight, preferably from 10 to 90% by weight, with respect to the overall weight of the PU resin, of a recycled PU resin.

Preferably the NWF comprises a quantity of at least one recycled synthetic fibre not exceeding 70% by weight, preferably not exceeding 60% by weight, with respect to the overall weight of the NWF.

The synthetic fibre is preferably selected from: polyester fibre, polyamide fibre, or combinations thereof. Preferably the polyester fibre is polyethylene terephthalate (PET) , while the polyamide fibre is preferably nylon 6.6.

These fibres generally have a mean diameter not exceeding 170 microns, preferably not exceeding 100 microns. In general a mean diameter not exceeding 10 microns characterises the class of the so-called "microfibres" , while a mean diameter in excess of 10 microns but not exceeding 170 microns identifies the class of the so-called "minifibres" .

The quantity of recycled fibre in the NWF may vary within wide limits, above all in relation to the mean diameter of the fibres used. In particular the Applicant has found that for a mean diameter of more than 10 microns but not exceeding 170 microns the quantity of recycled fibre is preferably from 20% by weight to 100% by weight with respect to the overall weight of the NWF, while for a mean diameter not exceeding 10 microns the quantity of recycled fibre is preferably from 0 to 20% by weight with respect to the overall weight of the NWF.

The upper according to this invention generally has a thickness from 0.6 to 2.5 mm, preferably from 0.7 to 2.0 mm. According to a preferred embodiment the shoe according to the present invention further comprises a midsole placed between the outsole and the upper essentially comprising an expanded polymer material selected from ethylene-vinyl acetate copolymers (EVA) and polyurethanes (PU) . Preferably at least 5% by weight, and more preferably from 10% by weight to 50% by weight, of the said expanded polymer material is a recycled polymer material .

According to another preferred embodiment the shoe according to this invention further comprises a lining, applied to the inner surface of the upper, formed from a synthetic material selected from those which may be used for the upper, but of lesser thickness. In general the lining has a thickness from 0.5 to 1.0 mm, preferably from 0.7 to 0.9 mm.

The weight of the lining, if any, is such as to constitute from 20% to 70%, preferably from 30% to 60%, of the overall weight of upper and lining.

In order to obtain a quality shoe without reducing the overall amount of recycled material, the shoe according to the present invention preferably comprises: an upper comprising at least one synthetic material as defined above wherein the amount of recycled PU and of synthetic fiber is substantially null; a lining, applied onto the inner surface of the upper, essentially constituted by a synthetic material comprising: from 20% by weight to 60% by weight, preferably from 30% by weight to 50% by weight, of a non-woven fabric (NWF) formed from at least one synthetic fibre; from 40% by weight to 80% by weight, preferably from 50% by weight to 70% by weight, of at least one polyurethane resin (PU) , wherein the PU resin comprises from 70 to 100% by weight, with respect to the overall weight of the PU resin, of a recycled PU resin and the NWF is formed from at least one synthetic fiber comprising from 20 to 60% of at least one recycled synthetic fiber, with respect to the overall weight of NWF.

According to another preferred embodiment the shoe according to the present invention further comprises an insole comprising: from 10% by weight to 45% by weight, preferably from 15% by weight to 35% by weight, of a polyester fibre (PES) , from 15% by weight to 60% by weight, preferably from 20% by weight to 50% by weight, of a synthetic latex (PU) , from 20% by weight to 70% by weight, preferably from 25% by weight to 60% by weight, of a mineral filler (preferably calcium carbonate) . Preferably the PES fibre comprises at least 80% by weight, preferably at least 90% by weight, of a recycled PES fibre with respect to the overall weight of the PES fibre.

This invention will now be further illustrated with reference to the appended:

Figure 1, which illustrates a shoe according to the invention, shown in side view in partial cross-section.

Shoe (1) comprises an outsole (2) , that is the lower part of the shoe which is in direct contact with the ground (sometimes also called the "tread")/ which has a pattern in relief on its lower surface only so as to increase its adhesion to the ground. It should be noted that within the scope of this invention the outsole does not include further members connected to the tread which do not have a surface in direct contact with the ground (for example the midsole must not be regarded as being part of the outsole) . The outsole (2) is in general formed from a cross-linked elastomer material obtained by the cross-linking (usually sulphur cross- linking) of at least one diene elastomer polymer of natural or synthetic origin mixed with at least one reinforcing filler (usually carbon black, silica, or mixtures thereof) . The diene elastomer polymer may be selected for example from polybutadiene (BR) , butadiene-styrene copolymers (SBR), polyisoprene (IR), natural rubber (NR) , butadiene-acrylonitrile copolymers (NBR) and the like.

According to this invention the outsole (2) has a weight not exceeding 170 grams, preferably from 50 to 140 grams, for any size from size 35 to size 46 (inclusive) .

Above the outsole (2) there may be applied a midsole (3) of expanded polymer material in order to improve the comfort of the shoe, generally fixed to the outsole (2) by adhesive bonding (for example using polyurethane adhesives) . As illustrated in Figure 1, the midsole (3) may have a differentiated thickness, in particular a thickness which is greater at the points upon which the foot bears, that is in the heel area and in the anterior part of the outsole (2) .

Shoe (1) also comprises an upper (4) which forms the structure of the shoe designed to receive the foot, manufactured according to the invention. In addition to the synthetic material according to the invention, upper (4) may also comprise one or more inserts comprising fabrics, felts or meshes of natural fibres

(for example hemp or natural cotton) , artificial fibres

(for example nylon, polyester, mylar, kevlar, dacron, carbon fibres) , or combinations thereof. The artificial fibre inserts may be obtained, for example, from the materials used to manufacture sails, or tarpaulins

(e.g. for lorries) .

The above inserts generally have a weight such as to constitute from 30% to 80%, preferably from 50 to 70%, with respect to the overall weight of the upper.

The inner surface area of the upper (4) is usually lined with a lining (5) . In Figure 1 upper (4) is partly removed and lining (5) is turned outwards in to better illustrate lining (5) . Preferably lining (5) is formed from a synthetic material selected from those which may be used for upper (4) . Lining (5) is joined to upper (4) through adhesive bonding, preferably using water-based adhesives.

Shoe (1) may further comprise an insole (6) which is joined (usually by adhesive bonding) to the lower edge of the upper (4) to form the base to which the outsole (2) , which may possibly be already assembled with the midsole (3) , can then be adhesive bonded. The bonding of insole (6) to upper (4) and of outsole (2) to insole (6) is usually effected by heating using adhesives known as hot-melt adhesives, which are well known in the art .

In order to increase the comfort of the shoe a fixed or removable insole pad (7) is usually placed on top of the insole (6), and is formed of a soft antibacterial material which is suitably shaped so as to confer stability and support for the plantar arch of the foot. Preferably insole pad (7) is an agglomerate of expanded polyurethane flock. Preferably such agglomerate is obtained using recycled polyurethane; the percentage of recycled polyurethane with respect to the overall weight of the polyurethane present in the agglomerate generally lies between 70 and 100% by weight. The insole pad (7) is usually covered with a protective layer, for example of textile material, or also the same material which forms lining (5) .

In order to reinforce the structure reinforcing members (8a, 8b) are usually inserted at the ball of the foot and the heel, for example by adhesive bonding between upper (4) and lining (5) . These reinforcing members (8a, 8b) have the purpose of increasing the rigidity of shoe (1) at the points where the most intense mechanical stresses are applied. Reinforcing members (8a, 8b) may be formed of a laminate comprising an inner layer of rigid thermoplastic material (e.g. polypropylene, styrene-butadiene block copolymers) bound on at least one side to a fabric or a non-woven fabric of synthetic fibre (for example polyester) .

Finally shoe (1) usually comprises padding members (9) inserted between upper (4) and lining (5) in the areas of contact between shoe (1) and the top of the foot and the heel (known as the "collar" and "tongue") . An expanded mateirial such as that described for insole pad (7) may be iased as the material for these padding elements (9) .

Tables 1 and 2 shown below provide some examples of embodiments of the shoe according to the invention. These are ladies' shoes (Table 1) and mens' shoes (Table 2) manufactured using different synthetic materials for the upper. The total weight of material, the weight of material obtained by recycling, the percentage by weight of these recycled materials with respect to the total weight are provided for each part of the shoe. The quantities shown are the mean values for shoes from size 35 to size 40 (Table 1) and from size 41 to size 46 (Table 2) .

Table 3 shows the compositions of the synthetic materials used for the upper, the lining and for the insole pad, with the weight of each component, the recycled mateirial used therein and the percentage with respect to the total.

As far as the outsole is concerned, this is manufactured using a mixture having the following composition:

Virgin polymer- base 36% by weight

Recycled elastomer material 30% Il Reinforcing fillers 23% Il

Plasticisers and manufacturing auxiliaries 6% Il

Vulcanising agents 5% Il A mixture of polybutadiene (BR) and styrene-butadiene copolymer (SBR) ( containing approximately 23 % by weight of styrene) was used as the virgin polymer base . A mixture of 50% by weight of kaolin and 50% by weight of precipitated amorphous silica were used as the reinforcing f il ler . The recycled elastomer material comprised manufacturing of f cuts of the same mixture af ter punching out in order to obtain the outsole . The elastomer material used f or the outsole had the following properties:

Hardness 72 degrees Shore A

Density 1.19 g/cm³

Ultimate tensile strength 15 MPa (standard EN 12803)

Ultimate elongation 550% (standard EN 12803)

Abrasion resistance 190 mm³ (standard EN 12770)

The weight of the outsole with respect to the overall weight of the shoe was 28.8% for the ladies' shoes and 30.3% for the mens' shoes .

TABLE 1 (Ladies' shoes)

TABLE 2 (Mens shoes)

TABLE 3

Claims

1. A shoe comprising: an outsole, an upper associated with the outsole, wherein: the outsole essentially comprises an elastomer material comprising from 10% to 60% by weight with respect to the overall weight of the outsole of a recycled elastomer material, the said outsoZLe having a weight not exceeding 60% with respect to the overall weight of the shoe and an abrasion resistance not exceeding 250 mm , the upper comprising at least one synthetic material comprising from 20% by weight to 60% by weight of a non-woven fabric (NWF) formed fr-ora at least one synthetic fibre, from 40% by weight to 80% by weight of at least one polyurethane resin (PU) .

2. The shoe according to claim 1, wherein- the elastomer material of the outsole comprises from 20% to 50% by weight, with respect to the overall weight of the outsole, of a recycled elastomer material.

3. The shoe according to claim 1 or 2, wherein the outsole has a weight from 20% to 5O% with respect to the overall weight of the shoe.

4. The shoe according to claim 3, wherein the outsole has a weight from 25% to 4O% with respect to the overall weight of the shoe.

5. The shoe according to any of the preceding claims, wherein the outsole has an abrasion resistance from 100 mm³ to 200 mm³.

6. The shoe according to any of the preceding claims, wherein the synthetic material of the upper comprises from 30% by weight to 50% toy weight of a non- woven fabric (WWF) formed from at least one synthetic fibre, from 50% by weight to 70% by weight of at least one polyurethane resin (PU) .

7. The shoe according to any of the preceding claims, wherein the PU resin of the synthetic material comprises at least 5% by weight of a .recycled PU resin with respect to the overall weight of tϊie PU resin.

8. The shoe according to claim 7_r wherein the PU resin of the synthetic material compr-ises from 10 to

90% by weight of a recycled PU resin with respect to the overall weight of the PU resin.

9. The shoe according to any of the preceding claims, wherein the NWF comprises a quantity of at least one recycled synthetic fibre not exceeding 70% by weight with respect to the overall weight of the NWF.

10. The shoe according to claim 9, wherein the NWF comprises a quantity of at least one recycled synthetic fibre not exceeding 60% by weight with, respect to the overall weight of the NWF.

11. The shoe according to any of the preceding claims, wherein the synthetic fibre for the NWF is selected from polyester fibre, polysmide fibre, or combinations thereof.

12. The shoe according to claim 11, wherein the synthetic fibre of the NWF is selected from polyethylene terephthalate (PET) and nylon 6.6, or combinations thereof.

13. The shoe according to any of the preceding claims, wherein the synthetic fibre of the NWF has a mean diameter not exceeding 170 microns .

14. The shoe according to claim 13, wherein the synthetic fibre of the NWF has a mean diameter not exceeding 100 microns.

15. The shoe according to claim 13, wherein the synthetic fibre of the NWF has a mean diameter not exceeding 10 microns.

16. The shoe according to claim 13, wherein the synthetic fibre of the NWF has a mean diameter exceeding 10 microns and not exceeding 17O microns.

17. The shoe according to claim IS, wherein the NWF has a quantity of recycled fibre from. 20% by weight to 100% by weight with respect to the overall weight of the NWF.

18. The shoe according to claim 15, wherein the NWF has a quantity of recycled fibre from zero to 20% by weight with respect to the overall weight of NWF.

19. The shoe according to any of the preceding claims, further comprising a midsole located between the outsole and the upper essentially comprising an expanded polymer material selected from ethylene-vinyl acetate (EVA) and polyurethane (PU) copolymers.

20. The shoe according to claim 3-9, wherein at least 5% by weight of the said expanded polymer material is a recycled polymer material .

21. The shoe according to claim 20 , wherein from 10% by weight to 50% by weight of the said expanded polymer material is a recycled polymer material.

22. The shoe according to any of the preceding claims, further comprising a lining applied to the inner surface of the upper formed from a synthetic material selected from those which may bfe used for the upper.

23. The shoe according to any of the preceding claims, further comprising an insole comprising from 10% by weight to 45% by weight of a polyester fibre (PES) , from 15% by weight to 60% by weight of a synthetic latex (PU) , from 20% by weight to 70% by weight of a mineral filler.

24. The shoe according to claim 23, wherein the insole comprises from 15% by weight to 35% toy weight of a polyester fibre (PES) , from 20% by weight to 50% by weight of a synthetic latex (PU) , from 25% by weight to 60% by weight of a mineral filler.

25. The shoe according to claim 23 or 24, wherein the PES fibre comprises at least 80% by weight of a recycled PES fibre with respect to the overall weight of the PES fibre.

26. The shoe according to claim 27, wherein the PES fibre comprises at least 90% by weight of a recycled PES fibre with respect to the overall weight of the PES fibre.

27. The shoe according to any of the preceding claims, wherein for any size from size 35 size 46

(inclusive) the outsole has a weight not exceeding 170 grams .

28. The shoe according to any of the preceding claims, wherein for any size from size 35 to size 46 (inclusive) the outsole has a weight from. 50 to 140 grams .

29. The shoe according to any of the preceding claims, wherein in addition to the synthetic material the upper also comprises one or more inserts comprising fabrics, felts or meshes of natural fibres, artificial fibres, or combinations thereof.

30. The shoe according to claim 29, wherein said inserts have a weight such as to constitute from 30% to 80% with respect to the total weight of the -upper.

31. The shoe according to claim 30, wherein said inserts have a weight such as to constitute frrom 50% to 70% with respect to the total weight of the upper.

32. The shoe according to claim 22, wherein the lining is joined to the upper through adhesive bonding with a water-based adhesive.

33. The shoe according to claim 22 or 32 , wherein the lining has a weight such as to constitute from 20% to 70% of the overall weight of upper and lining.

34. The shoe according to claim 33, wherein the lining has a weight such as to constitute from 30% to

60% of the overall weight of upper and lining.

35. The shoe according to anyone of claims 22, 32, 33 and 34, wherein the synthetic material included in the upper comprises an amount of recycled PU and of synthetic fiber substantially null; and wherein the lining is essentially constituted by a synthetic material comprising: from 20% by weight to 60% by weight of a non-woven fabric (NWF) formed from at least one synthetic fibre; from 40% by weight to 80% by weight of at least one polyurethane resin (PU) , wherein the PU resin comprises from 70 to 100% by weight, with respect to the overall weight of the PU resin, of a recycled PU resin and the NWF is formed from, at least one synthetic fiber comprising from 20 to 60% of at least one recycled synthetic fiber, with respect to the overall weight of NWF.