[0001] This invention relates to a method for making a covered fabric.
[0002] The invention also relates to a relative covered fabric obtained using the above-mentioned
method.
[0003] In particular, the invention relates to a method for making a fabric covered with
at least one layer of polyurethane spread on it.
[0004] The term "covered fabric" means a base fabric (or support fabric) on which a layer
of plastic material, for example polyurethane, is applied.
[0005] The application of the layer of plastic material allows the end product to be given
new technical and aesthetic features.
[0006] Covered fabrics are widely used, for example, in the production of footwear, items
of clothing or accessories, and more generally in the clothing, automotive or furnishing
sectors.
[0007] Currently, the layer of plastic material which is applied on the support fabric is
made, for example, of polyurethane or PVC (polyvinylchloride), depending on the technical
features required.
[0008] Polyurethane lends itself, for example, to various applications in which characteristics
of softness, elasticity and breathability are required.
[0009] With reference to the prior art methods for making covered fabrics and in particular
to the prior art methods wherein the layer of plastic material is made of polyurethane,
it may be stated that a good end product can be made available to a user, which, however,
is not free from drawbacks.
[0010] In particular, a major drawback is due to the fact that the prior art methods are
often unable to provide a product wherein the plastic layer has a suitable structure,
in terms, for example, of density and thickness.
[0011] This is because the polyurethane molecules, according to the prior art methods, are
substantially unable to layer themselves, resulting in the making of layers with a
very reduced thickness.
[0012] In particular, according to the prior art methods, an attempt to layer the polyurethane
to increase the thickness leads to surface defects which are unacceptable in terms
of appearance.
[0013] Polyvinylchloride, on the other hand, lends itself, for example, to applications
in which a predetermined degree of structure is required.
[0014] For example, using polyvinylchloride it is possible to obtain a layer of plastic
material with a high density and high thickness.
[0015] However, the prior art methods based on the application of a plastic layer of polyvinyl
chloride are also not free from drawbacks.
[0016] In effect, although this material guarantees a good structure, it has several defects
since it is unable to guarantee optimum technical and mechanical characteristics,
in terms of softness to touch, elasticity, flexibility and breathability.
[0017] Another drawback of the prior art methods is due to the fact that they do not always
allow a product to be provided which is inexpensive and simple to make.
[0018] Another disadvantage of the prior art methods is due to the fact that they do not
always allow a product to be supplied which is environmentally friendly and with a
low environmental impact.
[0019] The aim of this invention is therefore to provide a method for making a covered fabric
and a relative covered fabric which is able to overcome the drawbacks of the prior
art.
[0020] A further aim of this invention is to provide a method for making a covered fabric
and relative covered fabric which are able to provide a product with optimised technical
and mechanical characteristics.
[0021] Another aim of the invention is to provide a method for making a covered fabric and
relative covered fabric which are simple and inexpensive to implement (method) and
make (product).
[0022] Another aim of this invention is to provide a method for making a covered fabric
and relative covered fabric which have a low environmental impact.
[0023] According to the invention, these aims and others are achieved by a method for making
a covered fabric and the relative covered fabric comprising the technical features
described in the accompanying claims.
[0024] The technical features of the invention, with reference to the above-mentioned aims,
are clearly described in the accompanying claims and its advantages are apparent from
the detailed description which follows.
[0025] The method for making a covered fabric according to this invention, hereinafter also
referred to simply as "method", comprises the step of preparing a support fabric.
[0026] The term "support fabric" is used to mean any fabric generated by an interlacing
of threads of natural or synthetic origin.
[0027] Advantageously, the support fabric comprises cotton or polyester, or a mixture of
them.
[0028] The method according to this invention comprises the step of preparing a solution
of polyurethane particles dispersed in water.
[0029] Advantageously, the step of preparing a solution comprises a step of preparing particles
of polyurethane having at least 30% by weight of polyurethane derived from renewable
vegetable source.
[0030] This allows the effects of the environmental impact to be limited, guaranteeing the
possibility of making available an environmentally-friendly and sustainable product.
[0031] Advantageously, the step of preparing a solution comprises the step of mixing surface-active
substances with the solution, in such a way as to disperse the polyurethane particles
in water.
[0032] The term "surface-active substances" refers to substances with a large emulsifying
capacity.
[0033] In particular, the surface-active substances are partly polar and partly apolar.
[0034] The apolar part of these surface-active substances attaches itself to the polyurethane
particles (neutral base) making them charged.
[0035] In this way, these charged polyurethane particles disperse in the water floating,
instead of stabilising on the bottom as would occur without the use of the surface-active
substances.
[0036] The method according to this invention also comprises a step of foaming with particles
of a gaseous mixture the solution of polyurethane particles, to obtain foamed polyurethane.
[0037] In this way, the density of the solution is reduced to increase the thickness.
[0038] Advantageously, the foaming step is performed by introducing air.
[0039] The method according to this invention comprises a step of spreading at least one
surface of the support fabric with the foamed polyurethane to obtain a spread support
fabric.
[0040] Following the above-mentioned spreading step, the spread support fabric has a layer
of plastic material (air foamed polyurethane) characterised by a high thickness and
low density.
[0041] The method according to this invention comprises a step of stabilising the foamed
polyurethane on the spread support fabric.
[0042] Advantageously, the stabilising step is performed by means of an oven.
[0043] By using an oven, that is to say, by increasing the temperature of the support fabric
and of the foamed polyurethane, the quantity of water present in the polyurethane
evaporates, leaving a solid microcellular structure on the support fabric.
[0044] The method according to this invention comprises a step of pressing the foamed polyurethane
on the support fabric in such a way as to eliminate the air and obtain a layer of
polyurethane.
[0045] The pressing step allows the air to be eliminated so as to increase the density of
the polyurethane layer, whilst maintaining a high thickness.
[0046] This step therefore allows an optimum structure to be given to the finished product,
whilst maintaining unchanged all the advantageous features of the polyurethane (that
is, for example, softness to touch, flexibility, elasticity and breathability).
[0047] Advantageously, the pressing step is performed by means of a pair of rollers, that
is to say, moving the spread support fabric through the pair of rollers.
[0048] Alternatively, the pressing step is performed by means of a press.
[0049] The method according to this invention also comprises a step of finishing the covered
fabric.
[0050] The finishing step comprises a step of spreading a further layer of alcoholic-based
polyurethane on the covered fabric.
[0051] The term "alcoholic-based polyurethane" means a polyurethane dissolved in alcohol
with a high molecular weight, for example greater than 80 grams\mole (g\mol). For
example, alcoholic-based polyurethanes which can be used in this invention are: methoxypropanol,
dipropylene methyl ether, dimethyl carbonate.
[0052] This makes it possible to define in an optimum manner the colour of the finished
product and make it pleasant to the touch.
[0053] The finishing step also comprises a step of printing a graphical pattern on the covered
fabric.
[0054] Advantageously, the printing step is performed in a digital manner.
[0055] Alternatively, the printing step is performed by means of printing cylinders.
[0056] The finishing step comprises a step of embossing the covered fabric.
[0057] This embossing step makes it possible to form protrusions on the covered fabric and
to give it a desired degree of sheen and roughness.
[0058] The invention also relates to a covered fabric made using the method described above.
[0059] The covered fabric according to this invention comprises a support fabric and a first
plastic layer defined by the above-mentioned polyurethane particles.
[0060] The plastic layer is stabilised on the support fabric.
[0061] As explained above, the method according to this invention allows the production
of the plastic layer with a high thickness and high density.
[0062] Advantageously, the covered fabric according to the invention comprises a second
plastic layer of alcoholic-based polyurethane.
[0063] Advantageously, moreover, the covered fabric comprises a graphical pattern made on
the above-mentioned second plastic layer.
[0064] Advantageously, the second plastic layer has a rough upper surface.
[0065] The method for making a covered fabric and relative covered fabric according to the
invention overcome the above-mentioned drawbacks and achieve important advantages.
[0066] The first advantage achieved by the method for making a covered fabric and relative
covered fabric according to this invention is due to the fact that an end product
is provided which is optimised in terms of technical and mechanical characteristics.
[0067] In other words, the covered fabric made using the method according to this invention
comprises a plastic layer which is able to combine the typical advantageous properties
of polyurethane (breathability, softness, flexibility and resistance to twisting),
with a high degree of density and thickness.
[0068] Another advantage achieved by the method for making a covered fabric and the relative
covered fabric according to this invention is due to the fact that it provides an
environmentally-friendly product with a low environmental impact.
1. A method for making a covered fabric, comprising the following steps:
- preparing a support fabric;
- preparing a solution of polyurethane particles dispersed in water;
- foaming said solution of polyurethane particles with particles of a gaseous mixture,
to obtain foamed polyurethane;
- spreading at least one surface of said support fabric with said foamed polyurethane
to obtain a spread support fabric;
- stabilising said foamed polyurethane on the support fabric heating said support
fabric and said foamed polyurethane in such a way that the water present in said foamed
polyurethane evaporates defining a solid microcellular polyurethane structure on the
support fabric;
- pressing said foamed polyurethane on said support fabric in such a way as to eliminate
said gaseous mixture.
2. The method according to claim 1, characterised in that said foaming step is performed by introducing air.
3. The method according to any one of the preceding claims,
characterised in that said stabilising step comprises the steps of:
- preparing an oven;
- moving said spread support fabric through said oven in such a way that the water
present in said polyurethane evaporates at least partly.
4. The method according to any one of the preceding claims, characterised in that said step of preparing a solution of polyurethane particles dispersed in water comprises
a step of preparing polyurethane particles having at least 30% by weight of polyurethane
derived from a renewable vegetable source.
5. The method according to any one of the preceding claims, characterised in that said step of preparing a solution comprises the step of mixing surface-active agents
with said solution in such a way as to disperse said polyurethane particles in water.
6. The method according to any one of the preceding claims, characterised in that said pressing step is performed by a pair of rollers.
7. The method according to any one of the preceding claims, characterised in that it comprises a step of finishing said covered fabric.
8. The method according to the preceding claim,
characterised in that said finishing step comprises the steps of:
- spreading a further alcoholic-based layer of polyurethane on said covered fabric;
- printing a graphical pattern on said covered fabric.
9. The method according to the preceding claim, wherein said alcoholic-based polyurethane
comprises a polyurethane dissolved in alcohol with a molecular weight greater than
80 grams\mole (g\mol).
10. A covered fabric made using the method according to claims 1 to 9.