IT201700012184A1 - MANUFACTURED IN SHEET, PARTICULARLY INTENDED FOR THE REALIZATION OF FOOTWEAR, GARMENTS AND CLOTHING ACCESSORIES, UPHOLSTERY OR SIMILAR, AND ITS RELATED PROCEDURE - Google Patents

Description

"PRODUCT IN SHEET, PARTICULARLY INTENDED FOR THE PRODUCTION OF FOOTWEAR, GARMENTS AND CLOTHING ACCESSORIES, UPHOLSTERY OR SIMILAR, AND RELATED PRODUCTION PROCESS".

DESCRIPTION

The present invention relates to a sheet product, particularly intended for the production of footwear, garments and accessories of clothing, upholstery or the like, and the related manufacturing process.

The manufacture and use of fabrics, fabrics, leathers or other sheet products used in the field of clothing, accessories and upholstery are known.

They are used for the production of footwear, leather goods, bags, etc, or for the upholstery of padded parts of furniture components, car interiors, motorcycle saddles and the like.

These manufactured articles are made using synthetic materials, particularly polymers, such as for example polyurethane, polyesters and PVC. A typical example of an article in the form of a sheet is represented by synthetic leather, intended for various uses, including the production of bags.

Synthetic leather is normally made of polyurethane and can have different types of structure and finish.

This product made of polyurethane includes among its peculiarities those of being light, wear-resistant, water-repellent, easy to use and clean.

However, traditional sheet products have some drawbacks. Being made of polymeric materials, these artifacts have a very poor ability to dissipate heat, causing considerable inconvenience to the user due to the perceived temperature increase, especially in the hottest periods of the year.

In particular, in the event that the product is used for the production of garments and clothing accessories, the rise in the perceived temperature causes an increase in sweating, resulting in considerable inconvenience.

This drawback is found in a particular way in the event that the sheet product is intended for use in the footwear sector.

In fact, the increase in temperature inside the shoe and the incorrect perspiration of the foot lead to problems relating to the user's hygiene and comfort.

The main task of the present invention is to devise a product in sheet, particularly intended for the production of footwear, garments and accessories of clothing, upholstery or the like, and the related manufacturing process that allow to improve the dissipation of heat and to reduce the temperature. perceived by the user.

Another object of the present invention is to devise a sheet product, particularly intended for the production of footwear, garments and accessories of clothing, upholstery or the like, and the related manufacturing process that allow to obtain a high level of comfort for the user.

A further object of the present invention is to devise a sheet product, particularly intended for the production of footwear, garments and accessories of clothing, upholstery or the like, and the related manufacturing process which allow to reduce sweating due to contact with the product itself and improve hygiene, especially if it is used in the footwear sector.

Another object of the present invention is to devise a sheet product, particularly intended for the production of footwear, garments and accessories of clothing, upholstery or the like, and the related manufacturing process which allow to overcome the aforementioned drawbacks of the prior art in the field of a simple, rational, easy and effective to use and low cost solution.

The aforementioned purposes are achieved by the present process for manufacturing a sheet product, particularly intended for manufacturing footwear, garments and accessories of clothing, upholstery or the like, according to claim 1.

The above objects are also achieved by the present sheet product, particularly intended for the production of footwear, garments and accessories of clothing, upholstery or the like, according to claim Other characteristics and advantages of the present invention will become more evident from the description of an embodiment preferred, but not exclusive, product in sheet, particularly intended for the production of footwear, garments and accessories of clothing, upholstery or the like, and the related manufacturing process, illustrated by way of example, but not limited to, in the accompanying drawings in which: Figure 1 is an axonometric view of the step of mixing graphene to a polymeric material envisaged by the method according to the invention;

Figure 2 is an axonometric view of the step of spreading a layer of primer on a transfer sheet envisaged by the method according to the invention;

Figure 3 is a sectional view of the step of drying the sheet envisaged for the first time by the method according to the invention;

Figure 4 is an axonometric view of the step of spreading a layer of composite material envisaged by the method according to the invention;

Figure 5 is a sectional view of the step of drying the sheet envisaged by the method according to the invention a second time;

Figure 6 is an axonometric view of the step of spreading an adhesive layer envisaged by the method according to the invention;

Figure 7 is a sectional view of the step of drying the sheet envisaged by the method according to the invention a third time;

figure 8 is an axonometric view of the step of making a first main face of a substrate adhere to the adhesive layer provided by the method according to the invention;

Figure 9 is an axonometric view of the step of removing the transfer sheet 6 envisaged by the method according to the invention;

Figure 10 is a sectional view of the sheet product according to the invention;

Figure 11 is an axonometric view of the sheet product according to the invention in one mode of use;

Figure 12 is a t / T graph of a SAMPLE 1 and relative reference according to the invention;

Figure 13 is a t / T graph of a SAMPLE 2 and relative reference according to the invention.

With particular reference to figures 1 to 9, a process is illustrated for the manufacture of an article in sheet 1, particularly intended for the production of footwear, garments and accessories of clothing, upholstery or the like.

The process for the manufacture of an article in sheet 1, particularly intended for the production of footwear, garments and accessories of clothing, upholstery or the like, comprises at least the following steps: - a step I of mixing graphene 2 with at least one polymeric material to obtain a composite material 3; and

- a step II of applying the composite material 3 on a substrate 4 in sheet form.

Graphene is an allotropic form of elemental carbon, consisting of a monatomic layer of sp <2> hybridized carbon atoms.

It is therefore a practically two-dimensional material, as it has an extremely large surface with respect to its thickness, which is equal to the thickness of an atom.

Its particular structure makes it an extremely flexible material, resistant from a mechanical point of view, but also with a high thermal conductivity.

The step I of mixing the graphene to the polymeric material allows to obtain a composite material 3, that is a material with a polymeric matrix in which the graphene 2 is dispersed.

The presence of graphene 2 in composite material 3 modifies the properties of the polymeric material, making it more resistant from a mechanical point of view, but above all conductive from a thermal point of view.

Preferably, graphene 2 is mixed with polyurethane; however, alternative solutions are not excluded in which one or more polymeric materials other than polyurethane are used.

Usefully, the mixing step I comprises the step of adding at least one antibacterial additive chosen from echinacea extract and malaleuca extract to the polymeric material and to graphene, in order to improve the properties of the composite material by counteracting battery proliferation. The step II of applying the composite material 3 on the substrate 4 comprises at least the following steps:

- a step III of distributing a primer layer 5 on a transfer sheet 6;

- a step IV of drying the transfer sheet 6 a first time; - a step V of distributing the composite material 3 on the primer layer 5 to form at least one composite layer 7;

- a step VI of drying the transfer sheet 6 a second time; - a step VII of distributing an adhesive layer 8 on the composite layer - a step VIII of drying the transfer sheet 6 a third time; - a step IX of making a first main face 9 of the substrate 4 adhere to the adhesive layer 8; and

- one step X to remove the transfer sheet 6.

Conveniently, the transfer sheet 6 consists of a sheet of paper having a predefined grain such as to reproduce the desired surface finish of the sheet product 1.

Advantageously, step III of distributing the primer layer 5 is carried out by spreading the primer layer itself on the transfer sheet 6 by means of a blade 11 which slides at a height fixed by the sheet itself. The primer layer 5 confers smoothness and surface resistance to the sheet product 1 and is made at least in part of polyurethane.

Following each of the distribution steps III, V, VII, respectively, the drying steps IV, VI, VIII of the transfer sheet 6 are carried out, in order to fix the distributed material and optimize the spreading of the next layer.

In particular, at least one of step IV of drying a first time, step VI of drying a second time and step VIII of drying a third time are carried out in an oven under the following operating conditions:

- temperature: 120 ÷ 180 ° C

- time: 1 ÷ 10 min.

The adhesive layer 8 used in the distribution step VII consists of a one-component aromatic adhesive; however, the use of different types of adhesive materials is not excluded.

Usefully, the adhesive layer 8 allows the bonding of the layers 5, 7 to the substrate 4.

The step IX of making the first main face 9 of the substrate 4 adhere to the adhesive layer 8 therefore has the function of making the layers 5, 7 adhere and fix on the substrate itself.

Preferably, this substrate 4 is made of coagulated polyurethane; however, the use of polymeric materials other than coagulated polyurethane is not excluded.

Subsequently, in step X the transfer sheet 6 is removed, obtaining the product in sheet 1.

Advantageously, the manufactured article in sheet 1 thus obtained comprises:

- at least the substrate 4 in sheet form comprising at least the first main face 9 and at least a second main face 10; and - at least the composite material 3 which is distributed on the first main face 9 to form the composite layer 7 and which comprises at least the polymeric material mixed with graphene.

The presence of the composite layer 7 makes the sheet product 1 conductive from the thermal point of view.

The substrate 4 is made of breathable polyurethane, that is, having a microporous structure that allows the passage of air through the substrate itself.

In the context of this discussion, the term "breathable polyurethane" means a polyurethane having a water vapor permeability value greater than 1 mg / (cm <2> x h) measured by the provisions of the SATRA TM 47: 1997 standard .

Polyurethane is one of the most versatile polymeric materials in existence and allows to obtain products with very different properties and uses.

In particular, polyurethane is a material with high resistance to mechanical stress, chemically inert with respect to many organic and inorganic substances, resistant to humidity, high and low temperatures.

Graphene 2 in powder form is present in composite material 3 in a percentage by weight between 0.1% and 10%.

The possibility of adding the composite material 3 with at least one antibacterial additive selected from echinacea extract and malaleuca extract is not excluded, so as to make the product in sheet 1 antibacterial and antimicrobial.

Preferably, the product in sheet 1 comprises at least the adhesive layer 8 interposed between the first main face 9 and the composite layer 7, so that the latter is perfectly adhered to the substrate 4.

The sheet product 1 also comprises at least the primer layer 5 arranged on the composite layer 7.

The product in sheet 1 can be destined for various uses.

One possibility is to use the sheet product to cover at least one sheet-like support 12 shaped to form an insole 13 for footwear.

The use of this insole 13 allows to improve the thermal performance of the shoe, limiting the increase in internal temperature.

These characteristics also contribute to limiting sweating by the user, with a significant improvement also from the hygienic point of view.

EXAMPLE 1

A SAMPLE 1 of manufactured article in sheet 1 was made comprising the substrate 4 in breathable polyurethane, the adhesive layer 8, the composite layer 7 and the primer layer 5.

For the realization of the composite layer 7 were used:

- graphene in the form of nanoplachets (GNP), or structures consisting of a few sheets of carbon atoms stacked on top of each other, in a concentration of 2% by weight with respect to polyurethane, in particular GNP from Strem Chemicals; and

- a non-breathable polyurethane, in particular IMAPUR 2400BV from IMA, prepared by dispersion in a solution of dimethylformamide (DMF), with the addition of isocyanates and melamine, with a polyurethane concentration by weight between 30% and 50%.

The adhesive layer 8 was made using a non-transpiring one-component aromatic adhesive, which is ICAFLEX ADM383 from ICAP-SIRA.

For the realization of the primer layer 5, IMAPUR 1500/20 HR polyurethane from IMA was used, which is a type of non-breathable polyurethane.

A measurement of the cooling rate of SAMPLE 1 was performed by means of an infrared camera, following irradiation with a halogen lamp for a few minutes, until reaching at least 50 ° C.

The measurement was performed under the same conditions also on a REFERENCE 1 free of graphene.

Figure 12 shows the curves that describe the decrease in temperature over time, following irradiation, both for SAMPLE 1 and for REFERENCE 1.

The cooling rate is identified by the initial slope of the cooling curve.

It has been noted that the cooling rate is the same for the two samples examined.

The maximum temperature (TMAX) recorded is shown in Table 1.

TMAX

SAMPLE 1 62.1 ° C

REFERENCE 1 60.7 ° C

Table 1

It has been noted that the TMAX reached by SAMPLE 1 is greater than that reached by REFERENCE 1.

The higher TMAX is linked to the presence of graphene in the composite material 3, which improves its thermal conductivity; however, the use of non-breathable materials ensures that there are no changes in heat dissipation.

EXAMPLE 2

A SAMPLE 2 of manufactured article in sheet 1 was made comprising the substrate 4 in breathable polyurethane, the adhesive layer 8, the composite layer 7 and the primer layer 5.

In this case, for the realization of the composite layer 7 the following were used:

- graphene in the form of nanoplachets (GNP), in a concentration by weight with respect to polyurethane equal to 2%, in particular GNP from Strem Chemicals; and

- a breathable polyurethane, in particular NORETHANE NPU511 from NOVOTEX, prepared by dispersion in a solution of dimethylformamide (DMF), with the addition of isocyanates and melamine, with a concentration by weight of polyurethane between 30% and 50%.

The adhesive layer 8 was made using a breathable one-component adhesive, which is LARITHANE AB7198 from NOVOTEX.

For the realization of the primer layer 5 it was a material identical to that used for the realization of the composite layer 7, that is polyurethane NORETHANE NPU511 from NOVOTEX to which graphene GNP from Strem Chemicals was mixed in a concentration by weight equal to 2%. Also in this case a test to measure the cooling rate of SAMPLE 2 was carried out according to the same specifications reported for SAMPLE 1, comparing the results with a REFERENCE 2 comprising the same materials, but without graphene. Figure 13 shows the curves that describe the temperature trend over time following irradiation, both for SAMPLE 2 and for REFERENCE 2.

In this case, the cooling speed of SAMPLE 2 is minimally higher than that of REFERENCE 2.

The maximum temperature (TMAX) recorded is shown in Table 2.

TMAX

SAMPLE 2 57.0 ° C

REFERENCE 2 61.2 ° C

Table 2

In this second case, the TMAX reached by SAMPLE 2 is lower than that reached by REFERENCE 2.

This result is linked to the fact that the graphene contained both in the primer layer 5 and in the composite layer 7 allows to obtain a more homogeneous distribution of the T, with lower temperature maxima.

In addition, the use of breathable materials allows the heat to be dissipated faster than in the previous case, assisting the action performed by graphene.

In practice it has been found that the described invention achieves the proposed purposes.

In this regard, it is emphasized that the particular expedient of providing a composite layer containing graphene allows to improve the dissipation of heat.

In addition, the particular precaution of mixing graphene with breathable polyurethane allows to reduce the temperature perceived by the user and to obtain a high level of comfort for the user, especially during hot periods.

Furthermore, the use of the sheet product for the lining of shoe insoles allows the user to reduce sweating, with a significant improvement also from the hygienic point of view.

Claims (11)

CLAIMS 1) Process for the manufacture of an article in sheet (1), particularly intended for the production of footwear, garments and accessories of clothing, upholstery or the like, characterized in that it comprises at least the following steps: - mixing (I) graphene (2) with at least one polymeric material to obtain a composite material (3); and - applying (II) said composite material (3) on a substrate (4) in the form of a sheet. 2) Process according to claim 1, characterized in that said mixing (I) comprises the step of adding at least one antibacterial additive chosen from echinacea extract and malaleuca extract to said polymeric material and to said graphene (2). 3) Process according to claim 1, characterized in that said application comprises at least the steps of: - spreading (III) a primer layer (5) on a transfer sheet (6); - drying (IV) said transfer sheet (6) a first time; - distributing (V) said composite material (3) on said primer layer (5) to form at least one composite layer (7); - drying (VI) said transfer sheet (6) a second time; - distributing (VII) an adhesive layer 8 on said composite layer (7); - drying (VIII) said transfer sheet (6) a third time; - making (IX) adhere a first main face (9) of said substrate (4) on said adhesive layer (8); and - remove (X) said transfer sheet (6). 4) Process according to one or more of the preceding claims, characterized in that at least one of said drying a first time (IV), said drying a second time (VI) and said drying a third time (VIII) takes place under the following operating conditions : - temperature: 120 ÷ 180 ° C - time: 1 ÷ 10 min. 5) Product in sheet (1), particularly intended for the production of footwear, garments and accessories of clothing, upholstery or the like, characterized by the fact that it includes: - at least one substrate (4) in sheet form comprising at least one first main face (9) and at least one second main face (10); and - at least one composite material (3) distributed on said first main face (9) to form a composite layer (7) and comprising at least one polymeric material mixed with graphene (2). 6) Sheet product (1) according to claim 5, characterized in that said substrate (4) is made of breathable polyurethane. 7) Sheet product (1) according to claim 5 or 6, characterized in that said polymeric material is polyurethane. 8) Sheet product (1) according to one or more of claims 5 to 7, characterized in that said graphene (2) is present in said composite material (3) in a percentage by weight between 0.1% and 10%. 9) Sheet product (1) according to one or more of claims 5 to 8, characterized in that said composite material (3) comprises at least one antibacterial additive selected from echinacea extract and malaleuca extract. 10) Sheet product (1) according to one or more of claims 5 to 9, characterized in that it comprises: - at least one adhesive layer (8) interposed between said first main face (9) and said composite layer (7); and - at least one primer layer (5) arranged on said composite layer (7). 11) Use of the sheet product (1) according to one or more of claims 5 to 10, to cover at least one sheet-like support (12) shaped to form an insole (13) for footwear.