ES2726986T3 - A treatment plate of an appliance for the treatment of garments - Google Patents

Abstract

A treatment plate (10) of an appliance for the treatment of garments (100), whose treatment plate has a contact surface that, in use, slides on a garment (30) that is being treated, characterized in that said surface The contact is provided with a coating (20) comprising a metal oxide selected from the group consisting of titanium oxide, zirconium oxide, hafnium oxide, scandium oxide, or a mixture or combination thereof, and wherein said coating (20) has a thickness of less than 1 μm.

Description

DESCRIPTION

A treatment plate of an appliance for the treatment of garments.

Field of the Invention

The invention relates to a treatment plate of an appliance for the treatment of garments, whose treatment plate has a contact surface that, in use, slides on a garment that is being treated, whose contact surface has a coating, which has, among others, a favorable sliding behavior as shown by low friction. The invention also relates to an appliance for the treatment of garments, which comprises said treatment plate, and to methods for producing a coating on a contact surface of a treatment plate in an appliance for the treatment of garments.

Background of the invention

Low friction coatings allow contact surfaces to rub against each other with reduced friction, which reduces the effort to move apparel treatment devices, such as ironing devices such as an iron or a vaporizer. In addition, a scratch-resistant coating is very important for electrical appliances, and also for non-electrical appliances, such as frying pans, oven plates and the like, which benefit from low friction. Therefore, the use of a coating with a low coefficient of friction and good scratch resistance, to improve the tribological properties of the surfaces of household appliances, is constantly increasing.

An example of an appliance treatment plate for the treatment of garments for treating garments is the soleplate of an iron. In general, a separate layer, here called the coating layer, is applied to the surface of the floor facing away from the plate housing. During ironing, this coating layer comes into contact directly with the clothes to be ironed. A prerequisite for the proper functioning of the plate is that a coating layer of this type meets a large number of requirements. For example, the coating layer must, among other things, have satisfactory low friction properties on the clothes to be ironed, must be durable, corrosion resistant and scratch resistant, and have optimum hardness and high wear and fracture resistance. The coating layer material must meet extremely high requirements because the coating layer is exposed to substantial variations in temperatures ranging from 10 ° C to 300 ° C, with typical operating temperatures ranging from 70 ° C to 230 ° C. The required sliding behavior is obtained by having a coating that provides low friction in the hearth and this also reduces the effective force applied to the garment.

Various materials can be used as low friction materials of the screed siding for an iron, such as silicates applied by sol-gel, enamel, metal techniques (for example, nickel, chrome, stainless steel) which can be applied, by For example, as sheet material or thermal spray, hard anodized aluminum and diamond-type carbon coatings. An organic polymer can also be used as a floor covering, for example, polytetrafluoroethylene (PTFE). The low friction PTFE coating shows good sliding and non-stick properties, however, the mechanical properties, such as scratch resistance and wear resistance of the PTFE coating, are poor.

Another type of low friction coating has been described in US 5,943,799 A1, the low friction layer consists predominantly of aluminum oxide that is formed electrochemically, and the low friction coating shows good sliding behavior, thus As a good scratch resistance and it is easy to clean. However, the substrate used for the formation of the low friction metal oxide coating must be the same metal, which in this case is aluminum, and restricts the application of the coating.

A sol-gel coating for use in plates is described in US 5,592,765. The solgel coating shows good properties, such as good wear and scratch resistance, as well as good stain resistance.

US 7,339,142 discloses a plate having a hearth covered with a coating consisting of an outer layer, comprising at least one oxidation catalyst chosen from the platinoid oxides, and at least one inner layer, located between the support metallic and the outer layer, which comprises at least one oxidation catalyst chosen from the oxides of the transition elements of group 1b. In this reference, platinoids are considered to be elements that have properties similar to those of platinum, in particular, in addition to platinum, ruthenium, rhodium, palladium, osmium and iridium, therefore, the elements of groups 8-10 of The periodic table. It is claimed that the coating is self-cleaning, at the operating temperature of the device.

A plate having a hearth with an oxidation catalyst present on the outer surface of the hearth is known from the document from US 7,040,047. The catalytic oxidation agent is, according to this reference, any element, compound or composition capable of oxidizing, at a temperature at least equal to 90 ° C, any organic substance, for example, contained in dirt, or stains, which they find each other currently in the treatment (including washing and possibly softening) of textile articles or pieces (for example, bedding). As examples of active catalytic elements, palladium, platinum, vanadium and copper are mentioned. To increase the catalytic efficiency, copper, manganese or cobalt oxides may be present. The catalytically active form of the oxidizing agent, for example, platinum, can be obtained by calcination. This reference also mentions, by way of example, that the catalytic oxidation agent comprises a group IV metal of the periodic table; However, the use of these metals is not illustrated.

The teaching of the previous references is that the "organic dirt" captured by the hearth during ironing is oxidized so that it is detached from the hearth. It is said that even when the hearth is tarnished in a way that is barely visible, it will partially lose its slip qualities. Imperceptibly, with the dirt, the ironing will become more difficult, while the user will be worried about using a tarnished iron, for fear that he can alter the clothes.

US 2013/0247 430 describes a heating appliance that includes a metal substrate, at least a portion of which is covered with a self-cleaning coating that includes at least one oxidation catalyst selected from platinum oxides, and at least one dopant of said oxidation catalyst selected from the rare earth oxides. The self-cleaning coating is a two-layer coating that includes: an inner layer that at least partially covers the metal substrate and includes the dopant; and an outer layer in contact with the ambient air and which includes the oxidation catalyst. A procedure for producing such a heating appliance is also provided.

US 4,665,637 describes a fabric pressing device having a hearth composed of a metal base component or similar thermal conductive material that is coupled to the heat source of the pressing plate, and a ceramic layer adhered to the base component. The ceramic layer has a flat tissue pressing surface that preferably has a nominal smoothness of approximately two micrometers or more of surface roughness. The ceramic surface is highly resistant to wear and impact, is easy to clean and has excellent characteristics of static and dynamic friction in textile fabrics.

US 5146700 A describes a steam iron having a ceramic hearth and a method for mounting a ceramic hearth on an aluminum shoe portion of an iron.

Summary of the Invention

For the interest of constant low friction elements that are resistant to stains, scratches and wear of household appliances for the treatment of garments, such as in an ironing device for garments, such as an iron or a vaporizer, it is important that the coating maintains a good constant sliding behavior and good resistance to stains, scratches and wear in extreme conditions of use, for example, cyclic temperature changes ranging from room temperature to 250 ° C, frequent mechanical wear and environments with high steam or humidity.

It is one of the objectives of the invention to provide a treatment plate of an appliance for the treatment of garments, whose plate has a contact surface that, in use, slides on the clothes being treated, and shows improved properties with respect to to prior art appliances. The invention is defined in the independent claims. The dependent claims define advantageous embodiments.

The invention provides a treatment plate of an appliance for the treatment of garments for treating garments, whose treatment plate has a contact surface that, in use, slides on the garment being treated, and on which said surface of The contact is provided with a coating comprising a metal oxide selected from the group consisting of titanium oxide, zirconium oxide, hafnium oxide, scandium oxide or a mixture or combination thereof, and in which said coating has a thickness less than 1 pm,

Surprisingly, it has been found that the coatings of the mentioned metal oxides, especially the sol-gel coatings, show a very good and constant sliding behavior. The applicant has verified that thorough cleaning of the contact plate actually increases friction and that low friction is obtained again using (ie sliding) the plate on the garment. This effect is explained by the fact that organic lubricants, produced by contact with the coating, during use, with the article made of a non-metallic fabric, are retained and accumulated in the net of the produced coating and act as lubricants. This is contrary to the teaching of the prior art documents mentioned above, which teach that "organic dirt" has to be removed (by oxidation, for example, by a catalyst) for a constant sliding behavior. Surprisingly, it has appeared that the coating layer, especially in combination with the base layer (sol-gel) or intermediate layer, has low friction properties on the clothes to be ironed, is resistant to corrosion, is resistant to scratched and is durable. In addition, in tests and / or in demonstration devices, the coating layer has presented a very good hardness and high resistance to wear and fracture, even when the temperature is substantially increased.

In addition, it has been observed that the coefficient of friction of the present coatings, which is a measurement of the sliding behavior, falls almost immediately, that is, in a few seconds, at a very low value after coming into contact with a non-metallic fabric , and keeps this low value. The low coefficient of friction of the present coatings is generated, therefore, when using the appliance; It is not a property of the coating material itself. In addition, it is noted that non-metallic fabric should be understood as any material used for clothing and bedding, such as cotton, wool, silk, synthetic materials, such as polyester, etc. Although, in general, the coefficient of friction of ironing devices for garments, such as irons and vaporizers, tends to decrease over time, that is, the sliding behavior improves, it can take many hours of use before it stabilizes In a lower value. If the user has cleaned the coating surface, the friction coefficient returns to the original value and the sliding behavior worsens again, as will be explained below. However, the sliding behavior of the present coatings is always good and of low value once the first use has taken place. Even when trying to clean the coating with the usual cleaning agents, the low value of the friction coefficient is obtained in a matter of seconds from the beginning of the use of the appliance.

In this document, the phrase "treatment plate has a contact surface that, in use, slides on a garment that is being treated" and similar phrases are used. Furthermore, it is indicated that "said contact surface is provided with a coating (eg sol-gel) comprising a metal oxide selected from the group consisting of titanium oxide, zirconium oxide, hafnium oxide, oxide of scandium, or a mixture or combination thereof.Therefore, during use of the sol-gel coating layer of the invention, said sol-gel coating layer can thus slide, in effect, over the garment to be treated Other coatings cannot be excluded, therefore, the term "contact surface" refers especially to an outer surface of the layer farthest from the substrate on which the coating is located or the coatings are provided.

The coating according to the invention preferably (substantially) consists of titanium oxide, zirconium oxide, or a mixture or combination thereof, more preferably titanium oxide. Especially, the coating consists of at least 85% by weight, even more especially, at least 90% by weight, such as especially at least 95% by weight of titanium oxide, zirconium oxide, or a mixture or combination thereof, more preferably, titanium oxide (relative to the total weight of the coating).

In another specific specific embodiment, the coating does not comprise yttrium in an amount greater than 95% by weight with respect to the total weight of the metal (atom) in the coating. In another additional embodiment, the coating does not consist substantially of a yttrium oxide coating. Surprisingly, it has been experimentally observed that substantially pure yttrium oxide coatings have less advantageous properties than, for example, pure titanium coatings or a mixture or composition of titanium dioxide with one or more zirconium oxide, hafnium oxide , scandium oxide and yttrium oxide, especially with one or more of titanium oxide, zirconium oxide, scandium oxide and yttrium oxide. In addition, especially the weight of metals as one or more among the rare earth, manganese and cobalt metals, is less than 5% by weight, especially less than 1% by weight, even more especially less than 0.01% by weight, with respect to the total weight of the metal (atom) in the coating. Even more especially, the weight of metals such as one or more of manganese and cobalt, is less than 5% by weight, especially less than 1% by weight, even more especially less than 0.01% by weight, with respect to to the total weight of the metal (atom) in the coating. It appears that the present coating has superior properties over the manganese oxide coating or cobalt oxide coatings or coatings comprising one or more between manganese oxide and cobalt oxide (see also Fig. 2). In addition, the coating is also substantially free of platinoids (see also above). Especially, the weight of a platinoid is less than 5% by weight, especially less than 1% by weight, even more especially less than 0.01% by weight, with respect to the total weight of the metal (atom) in the coating.

In a specific embodiment, said coating consists substantially of (i) a titanium oxide, zirconium oxide or a mixture or combination of titanium oxide and zirconium oxide, or (ii) a titanium oxide, yttrium oxide or a mixture or combination of titanium oxide and yttrium oxide.

The advantages of metal oxide coatings, used in the invention, are that they show a low coefficient of friction, have a thickness of less than 1 pm and can be applied with a low temperature process (preferably at temperatures below 400 ° C ), such as a sol-gel process to obtain a sol-gel coating. In addition, they are transparent at a more preferred thickness of less than 400 nm. Especially, the metal oxide coating has a thickness ranging from 5 nm to 1 pm, especially from 5 nanometers to 400 nanometers. Another favorable property of these metal oxide coatings is that the triboelectric effect is reduced during rubbing / ironing, that is, the static charge accumulated during rubbing / ironing is reduced; This effect is also assumed to be the result of a type of accumulation of a layer of organic lubricating / contaminating particles (residues) in the coating. In addition, the present coating can be applied with relative ease, as if desired at once. Beyond that, it is not intrinsically necessary to include a post-application (sol-gel) finishing stage of the layer. This may be necessary, for example, when a thick ceramic layer is applied, such as that described in EP 0217014 / US 4665637. In this document the term "sol-gel procedure (coating)" and similar terms refer to the sol-gel process described herein.

In accordance with the present invention, said metal oxide-containing layer has a thickness of less than 1 µm, preferably less than 400 nm to maintain transparency and, preferably, a sol-gel coating. Said nanoplate can maintain the aesthetic appearance of the substrate and also allows to retain other mechanical and thermal properties of the contact surface, such as resistance to wear and fracture and the coefficient of expansion.

The coating will cover substantially the entire contact surface, although it is also possible for the coating to be applied in a pattern of non-contiguous portions that partially cover the entire contact surface. Therefore, the coating can, in particular embodiments, cover at least 80%, even more especially at least 90%, such as substantially the entire (contact) surface of the treatment plate.

In a preferred embodiment of the invention, the present treatment plate comprises a substrate having said contact surface on which said coating is applied, wherein said substrate is a metal, enamel, organic polymer, organosilicate or silicate substrate.

In another embodiment, the treatment plate comprises a metal contact surface, and said coating is applied directly on said metal contact surface.

According to a further embodiment, the treatment plate comprises a contact surface (preferably made of metal), and the plate further comprises at least one layer disposed between said contact surface and said coating in which said layer is preferably a metal composition, a layer of enamel, organic polymer, organosilicate or silicate. Said layer is also conveniently a sol-gel layer. Said layer disposed between said contact surface and said coating is also indicated herein as "intermediate layer" or "intermediate coating layer" or "base layer" or "base layer". This intermediate layer can be seen as a layer between the substrate, especially a metallic substrate, and the actual sliding layer.

Therefore, in a specific embodiment, the invention also provides a treatment plate of an appliance for the treatment of garments, whose treatment plate has a contact surface that, in use, slides on a garment being treated, wherein said contact surface is provided with a sol-gel coating comprising a metal oxide selected from the group consisting of titanium oxide, zirconium oxide, hafnium oxide, scandium oxide, yttrium oxide or a mixture or combination thereof, and wherein the treatment plate comprises a metal substrate and wherein the treatment plate further comprises at least one layer disposed between said metal substrate and said coating, said layer which is a composition of metal, a layer of enamel, organic polymer, organosilicate or silicate.

Especially, a combination of oxides is related to a layer of oxides where different oxides are mixed and it is possible to observe and define which regions belong to each oxide. There has been no chemical reaction (substantial) between the original oxides. Especially, a mixture (see also below) may refer to a layer where the oxides are mixed on a molecular / atomic / ionic scale where it cannot be differentiated to be a single type of oxide. Subsequently, a material is obtained in which the ions of the (original) oxides are in the same network (crystalline).

According to another embodiment, said intermediate coating layer consists of a silicate layer in which, optionally, said metal oxide, selected from titanium oxide, zirconium oxide, hafnium oxide, scandium oxide or a mixture or combination thereof. Said intermediate layer can be obtained especially by a sol-gel process (coating). Therefore, especially the intermediate coating layer, when available, is applied by a sol-gel coating process, and the coating layer, as described herein, is also applied by a coating process. of sol-gel (see also below).

Therefore, the invention especially provides a treatment plate of an appliance for the treatment of garments, whose treatment plate has a surface with a coating (especially sol-gel) on it, in which the coating, especially the coating sol-gel, comprises a metal oxide, in which the metal (of the metal oxide) comprises one or more of titanium, zirconium, hafnium, scandium. Said metal oxide may be a (substantially) pure oxide. Said metal oxide may also be a combination of oxides, such as a mixture of titanium oxide and yttrium oxide. Said metal oxide may also be a mixed oxide. For example, the coating may comprise a TiO2 coating. However, the coating may also comprise a coating of TiO2 and Y2O3 (mixed materials in the coating). A mixed oxide contains cations of more than one chemical element or cations of a single element in various oxidation states (or a combination thereof). When the materials are mixed, there are substantially two or more different crystalline materials next to each other, as in the previous examples TiO2 and Y2O3, while, in a mixed oxide, there is substantially a crystalline material with the mixed oxide cations, such as in the previous example yttrium and scandium, in the same crystal lattice. In use, one side of said lining may slide over a garment that is being treated (the other side may be in contact with the support, or an intermediate layer). Therefore, in embodiments, the term "metal oxide" may also be related to a combination of metal oxides and / or a mixed metal oxide. When metal precursors of a solution are mixed, the final oxide layer obtained after application and drying may contain a mixture of metal oxides or mixed metal oxides. In addition, the final metal oxide layer may be crystalline, partially crystalline or amorphous.

The invention is also related to a treatment plate that is a soleplate for an ironing appliance, with an ironing appliance comprising a treatment plate such as a screed as described above, and with an appliance for the treatment of garments that It comprises a treatment plate as described above. It has been found that even at low temperatures, the sliding behavior of the coated treatment plate according to the present invention is excellent, which allows low temperature ironing.

The invention is also related to methods for producing a coating on a contact surface of an appliance for the treatment of garments for treating garments, in which, in use, said contact surface slides on the garment being treated. Especially, the invention provides a method for producing a coating on a (contact) surface of a treatment plate of an appliance for the treatment of garments, in which, in use, said contact surface slides on a garment that is being treated, and wherein said coating has a thickness of less than 1 pm, the process comprising the steps of:

depositing on said contact surface a layer of a precursor material of a metal or compound, selected from titanium, zirconium, hafnium, scandium or a mixture or combination of these metals or compounds, wherein the precursor material comprises one or more between a hydrolysable precursor and a hydrolyzable precursor solution; Y

treating said layer to obtain a layer comprising titanium oxide, zirconium oxide, hafnium oxide, scandium oxide or a mixture or combination thereof.

With this procedure, a treatment plate of an appliance for the treatment of garments for treating garments can be provided, whose treatment plate has a contact surface that, in use, slides on the garment being treated, and in the that said contact surface is provided with a coating comprising a metal oxide selected from the group consisting of titanium oxide, zirconium oxide, hafnium oxide, scandium oxide or a mixture or combination thereof. During use, said coating, as described herein, will slide over the garment to be treated. The coating herein may also be indicated as "coating for treating garments" or "sliding layer".

In a first embodiment, the present process comprises the steps of depositing on said contact surface a layer of a hydrolysable precursor, preferably, an alkoxide precursor or an acetate precursor, of a metal, selected from titanium, zirconium, hafnium, Scandium or a mixture or a combination of these metals or compounds, and curing said layer to obtain a layer comprising titanium oxide, zirconium oxide, hafnium oxide, scandium oxide or a mixture or combination thereof.

Said process may comprise the deposition of the precursor compound by means of a dry chemical process, preferably a vapor deposition process.

In a second embodiment, the present process comprises the steps of preparing a hydrolysable precursor solution, preferably an alkoxide precursor or an acetate precursor, of a metal, selected from titanium, zirconium, hafnium or scandium, or a mixture or combination of these compounds, depositing a layer of said precursor solution on said contact surface, followed by drying, if necessary, and curing to obtain a layer comprising titanium oxide, zirconium oxide, hafnium oxide, scandium oxide, or a mixture or combination thereof.

In said process, the deposition can be carried out by means of a wet chemical process, preferably a dissolution process, more preferably a sol-gel process.

The metal alkoxide or acetate precursors, preferably used in the invention, are derivatives of isopropanolate or acetylacetonate thereof (ie, an isopropanolate or acetylacetonate derivative of alkoxide or acetate). Diketones such as acetyl acetone or ethyl acetoacetate can be used so that the precursors are less sensitive to water. However, the invention is not restricted to these precursors; Other alkanolates can also be used, other metal salts, such as acetates, can also be used, provided that they can easily be converted to the oxide form in the present process. Alkoxides can be modified, for example, by alkoxy and amino alcohols, p-diketones, p-ketoesters, carboxylic acids to provide metal alkoxide or metal alkoxide derivatives. Examples of suitable alkoxides and acetates are isopropoxide, isopropanolate, acetate, acetylacetonate, ethylacetoacetate, t-butylacetoacetate, etc.

The solvent used for the preparation of the precursor solution is preferably a lower alcohol, specifically ethanol, isopropyl alcohol, 2-butanol or 2-butoxyethanol.

Drying and curing of the deposited layer of an alkoxide precursor of a metal is preferably carried out at a temperature below 400 ° C. This layer can be deposited directly on the contact surface of the treatment plate.

In one embodiment, said contact surface of the treatment plate consists of a composition of metal, enamel, organic polymer, organosilicate or silicate.

In a preferred embodiment of the invention, said contact surface has been previously coated with at least one layer, which preferably consists of a metal composition, an enamel, an organic polymer, an organosilicate or silicate coating, more preferably a layer of metal oxide, made for example by a sol-gel technique. The precoated layer, that is, the intermediate layer, can especially provide mechanical strength and, in general, has a thickness of at least 1 pm, as in the range of 1 100 pm. The metal oxide coating (ie, a Ti, Zr oxide, etc.) of the invention especially provides the low friction function, and has a thickness especially less than 1 pm, such as 5-400 nm. As indicated above, the intermediate layer can be provided especially by a sol-gel process.

In the case of an iron, the metal oxide coating layer can be deposited on top of a single screed coating, which is preferably a silicate based coating, applied by a solgel process or by another procedure such as PVD , CVD and thermal spraying, which further improves the sliding behavior of the sol-gel based silicate coating. These procedures are procedures known to an expert. The sol-gel coating with the outer layer of metal oxide shows excellent and constant sliding behavior, while maintaining good resistance to wear, scratches and deformation.

The reason for preferring a sol-gel process for the formation of the oxide layer is its low cost. In addition, it is easy for industrialization. As indicated above, an advantage of the sol-gel layer is that it is easy for industrialization by, for example, a simple spray procedure instead of a vacuum procedure. Furthermore, it is favorable that the present coating, such as, for example, obtainable by spray painting the metal oxide layer, such as especially the titanium layer, and that the final layer does not need a subsequent finish as needed with, by example, plasma sprayed layers. In addition, the coating (or sliding layer) is transparent and non-opaque as the particle based coatings of the prior art. Therefore, it may not influence how the color of the coating is perceived. For example, when a base coat of color is applied, or when a print is available, this can still be seen through the coating. In this way, more design freedom is preserved than in some prior art solutions where the color is, for example, the intrinsic color of the plasma sprayed layer.

Said layer, located between the metal support of the plate and the outer layer, may contain, for example, a mixture of fine fillers of metal oxide and a sun such as silica sol and silanes, for example, organically modified silanes, which they provide good adhesion to the metal substrate as well as good mechanical properties, on which an outer layer of metal oxide is disposed, comprising at least one titanium oxide, zirconium, hafnium, scandium or yttrium or mixtures or combinations thereof . Compared to prior art systems without the outer coating of the inorganic metal oxide layer as defined herein, r has an excellent and more constant sliding behavior; The coefficient of friction of the lining on fabrics, for example, cotton, synthetics, linen and silk, is systematically a very low value. Especially, the support is a metal support. Therefore, especially the plate holder is a metal plate holder.

In this way, the coating causes the appliance, for example, an iron screed, to have an excellent and more constant sliding behavior, good wear, scratch and stain resistance on the surface of the appliance and in the articles in contact. , that is, fabrics, as will also be described below.

Therefore, the coating can be applied by a solution deposition process, such as a rotation coating, immersion coating or spraying process, or by a vapor deposition process, such as PVD oc Vd, or by a thermal spray procedure. Especially, the coating of the invention is applied by a solution deposition process, such as, for example, rotation coating, immersion coating or spray process. More especially, the deposition process comprises a sol-gel procedure.

In a further embodiment, the components of the sol-gel coating mentioned above are combined with the components of the metal oxide layer to produce a coating layer.

Therefore, the invention also provides a method for providing a sol-gel coating on a treatment plate of an appliance for the treatment of garments, wherein the treatment plate comprises a surface and, optionally, thereon a intermediate layer, wherein the process comprises providing said sol-gel coating on the surface of the treatment plate or the optional intermediate layer, in which this process comprises a sol-gel coating process, and wherein the sol-gel coating on the treatment plate or the optional intermediate layer comprises a metal oxide, in which the metal of the metal oxide comprises one or more of titanium, zirconium, hafnium, scandium, yttrium. Especially, during use, said coating, as described herein, will slide over the garment being treated. Therefore, during the use of the appliance for the treatment of garments, the treatment plate can be in contact with the garment being treated and move easily over this garment with relative ease, since the friction is low.

The invention is also related to a method for improving the sliding behavior of a treatment plate of an appliance for the treatment of garments, especially a screed for an ironing appliance, by applying a coating on a contact surface of said treatment plate It comprises a metal oxide selected from the group consisting of titanium oxide, zirconium oxide, hafnium oxide, scandium oxide or a mixture or combination thereof.

In addition, the specific embodiments described above with respect to the coating on the contact surface of a treatment plate, especially in an appliance for the treatment of garments, can also be applied to, and can be combined with, the process and the process embodiments described. in the present document.

The main element of the present invention is, therefore, a thin layer of metal oxide film that can be applied on a substrate by a sol-gel process, or by PVD, CVD or thermal spray process, especially by a sol-gel procedure, to improve the performance of the sliding coating on the garment. Therefore, the main element of the present invention is, therefore, a thin layer of metal oxide film that can be applied on a substrate, which already optionally includes a precoating (or indeed an intermediate layer) by means of a sol-gel procedure, or by PVD, CVD or thermal spray procedure, especially by a sol-gel procedure, to improve the performance of the sliding coating on the garment. This new low friction, anti-scratch, anti-wear and easy-to-clean metal oxide coating offers many advantages over conventional coatings due to its excellent and constant sliding behavior, as well as its properties against stains, scratches and wear .

Especially, a treatment plate is provided with a stack of layers, with a base layer and the sliding or coating layer as described herein. The base layer is directed to the treatment plate, and may even be in contact with the treatment plate. Especially, the sliding layer or lining when used slides on a garment that is being treated. Between the base layer and the sliding layer or coating, there may optionally be additional layers. Optionally, a print may be available between the base layer and the coating layer or sliding layer. Especially, most of the layers of the stack are sol-gel coatings. For example, printing can be a silicone based material. Therefore, in one embodiment, all layers, except optional printing, can be sol-gel layers.

These and other aspects of the invention will be apparent and will be clarified in reference to the embodiments described below.

Brief description of the drawings

These and other aspects, features and advantages of the present invention will be further explained by the following description of one or more preferred embodiments, with reference to the drawings, in which:

Fig. 1 is a diagram showing the reversible sliding effect on the ironing time of a prior art contact surface,

Fig. 2 is a diagram showing the sliding behavior over the ironing time of different contact surfaces, and

Figure 3 is a drawing schematically showing the structure of a garment treatment plate and the positioning of the article to be treated.

Detailed description of the invention

The invention will be better understood by reading the examples below and the accompanying drawings.

Referring to Fig. 1, the friction coefficient f (vertical axis, in arbitrary units) is shown as a function of the ironing time t (horizontal axis, in hours), using a plate having a contact surface without a metal oxide layer according to the invention. The right half of this drawing specifically illustrates the effect of cleaning the contact surface.

In general, for most coatings, the friction coefficient f of an ironing device for garments, such as a vaporizer or an iron, tends to decrease over time, that is, the sliding behavior improves, as shown In this diagram.

However, it may take many hours of use before it stabilizes at a lower value. If the user cleans the coating surface (at the moment m ^c ), the coefficient of friction f returns to the original value (as shown in the dotted line), which causes the sliding behavior to deteriorate again. Several hours of use are required before they stabilize at the lowest value, as indicated in the right half of Fig. 1.

Referring to Fig. 2, the friction coefficient f (vertical axis, in arbitrary units) is shown as a function of the ironing time t (horizontal axis, in hours), using a plate having a contact surface provided with a layer of titanium oxide (curve C), a layer of manganese oxide (curve B), or without an extra (outer) layer (curve A), on cotton. The favorable effect of the contact layer provided with a titanium oxide layer (curve C) is clearly shown: the contact surface with the titanium oxide layer not only stabilizes faster, but also stabilizes with a coefficient of lower friction. This offers a better and more constant sliding behavior. It has been found that this effect is present when using metal oxide layers of certain early transition metals, while late transition metals (eg, Mn) do not show such effect.

Referring to Figure 3, the structure of a garment treatment plate 10 with a contact surface in an appliance for the treatment of garments 100 is shown schematically. The treatment plate is provided with a liner 20, which will come into contact. with article 30 (consisting of a tissue) to be treated. Therefore, in fact, the contact surface of the clothing device is now the coating surface 20 furthest from the treatment plate. During use, said coating 20 can slide on the garment being treated.

The manufacture of the present metal oxide comprising the coating of the contact surface of an appliance for the treatment of garments will be explained below.

In order to achieve a good and constant sliding behavior, a thin layer of a metal oxide film is applied on a base layer (sol-gel layer), through a sol-gel process. The outer layer of metal oxide comprises at least one titanium oxide, zirconium, hafnium, scandium or mixtures thereof. The metal oxide layer is applied by the sol-gel process using metal alkoxide precursors, which are preferably selected from metal alkoxide precursors such as a proproxide, isopropoxide, butoxide or derivatives thereof modified with acetylacetonate or ethylacetoacetate. However, it will be obvious that other salts that can become an oxide form can also be used under the applied conditions.

The metal alkoxide precursors preferably used in the process of the invention are selected from titanium (IV), titanium (IV) isopropoxide, zirconium (IV), hafnium (IV), scandium acetylacetonate (IV) III).

For yttrium, yttrium (III) acetate is a suitable starting material. The solvent used to prepare the precursor solution is conveniently a lower alcohol, such as ethanol, isopropyl alcohol, 2-butanol or 2-butoxyethanol.

A coating preparation process for the present invention is described below; Ti, Zr and Y are used as examples.

Process:

Mix M (i-OPr) 4 (i.e. metal isopropoxide) with ethyl acetoacetate (MS) in a 1: 1 molar ratio and stir for 1 hour (preferably M = Ti or Zr)

Dilute the precursors with isopropyl alcohol in a concentration of 0.1% to 80%, preferably 0.5-40% before using.

The concentration of the precursors used can range between 0.1% and 80%, depending on the thickness required, preferably between 0.5 and 40%. After vaporizing and drying the base layer (also called sol-gel internal coating), the precursor solution is vaporized on top of the upper layer (sol-gel internal coating). After drying and curing at a temperature below 400 ° C, the outer layer of metal oxide is formed above the base layer (inner sol-gel layer). Depending on the amount of solution sprayed in the base layer, the thickness of the outer layer will vary from 1 to 1000 nanometers; It will be more preferably in the range of 5 nanometers to 400 nanometers for good appearance, sliding behavior and mechanical properties.

For yttrium, a procedure is as follows:

0.5 g of Y (Ac) ³ is dispersed in 25 ml of 2-butoxyethanol. Next, 0.38 g of acetylacetonate (2eq) are added together with 0.26 g of NH ³ (25%) (2eq) that offer a clear solution.

The resulting solution can be applied as described for titanium oxide and zirconium.

Mixtures of metal oxide can also be used. For example, it has been observed that yttrium zirconate or yttrium titanate offer good sliding layers.

For example, Y ² Ti ³ O ^g is formed by mixing the yttrium complex of the previous example with Ti (OPr) ³ EAA in a 2 to 3 ratio and applying the resulting solution as described for the Ti oxide layer or Pure Zr.

Some examples of other systems that have been prepared are:

TiPO ^x was made by mixing 0.5 g of Ti (OPr) ⁴ with 0.47 tributyl phosphate in 25 ml of BuOH. The resulting solution can be applied as described for titanium oxide and zirconium;

ZrPO ^x was made by mixing 0.5 g of Zr (OPr) ⁴ with 0.28 tributyl phosphate in 25 ml of BuOH. The resulting solution can be applied as described for titanium oxide and zirconium.

TiPO ^x or ZrPO ^x indicate a titanium phosphate or zirconium phosphate, respectively.

In addition to the sol-gel process, the metal oxide layer can also be applied by another procedure such as PVD, CVD or thermal spraying.

The coefficient of friction of the sol-gel coating with the outer layer of metal oxide (here TiO ² is used as an example) is measured from the IEC standard [IEC standard for the sliding and smoothness test IEC60311 (ED4.1) ]. A base layer (sol-gel layer) was also tested as a reference. The coefficient of friction of the coating with the outer layer of metal oxide on fabrics, for example, cotton, synthetic, linen and silk, etc., is systematically a very low value. Fig. 2 shows, as an example, the sliding behavior during the ironing time of the coating with an outer layer of metal oxide on the cotton. In comparison with the reference base layer (sol-gel coating), the sliding behavior of the base layer with outer metal oxide (TiO ² ) according to the invention is better and more constant during the time of use. In addition, the sliding behavior of certain materials has been evaluated. This has been done, on the one hand, based on theoretical evaluations and, on the other hand, it has been done through experimental work, in which a panel tests the plates that have the coatings indicated below, respectively, and compares the behavior sliding between the different coatings (Table 1):

Table 1: Sliding arrangement of a number of coatings:

From the table above, it is clear that the oxides of the invention have much better sliding properties than other oxides or phosphates or vanadates, etc.

The term "substantially" herein, as in "substantially all of the light" or "substantially consists", will be understood by one skilled in the art. The term "substantially" may also include embodiments with "totally", "completely", "all", etc. Therefore, in embodiments, the adjective can also be substantially eliminated. When applicable, the term "substantially" may also refer to 90% or more, for example, 95% or more, especially 99% or more, even more especially 99.5% or more, including 100%. The term "and / or" refers especially to one or more among the elements mentioned before and after "and / or". For example, a phrase "element 1 and / or element 2" and similar phrases may be related to one or more between elements 1 and 2. The term "comprising" may refer in one embodiment to "consisting of, but in another embodiment may also refer to" containing at least the defined species and, optionally, one or more other species".

In addition, the first, second and similar terms in the description and in the claims are used to distinguish between similar elements and not necessarily to describe a chronological sequence or order. It is to be understood that the terms used in this manner are interchangeable under suitable circumstances and that the embodiments of the invention described herein may function in sequences other than those described or illustrated herein.

The invention is further applied to a device comprising one or more of the characteristic features described in the description and / or shown in the accompanying drawings. The invention also pertains to a process or process comprising one or more of the characteristic features described in the description and / or shown in the accompanying drawings.

The various aspects analyzed in this patent can be combined to provide additional advantages. In addition, some of the features may form the basis for one or more divisional applications.

While the invention has been illustrated and described in detail in the drawings and the above description, it should be apparent to one skilled in the art that said illustration and description should be considered illustrative or exemplary and not restrictive. The invention is not limited to the described embodiments; rather, several variations and modifications are possible within the scope of protection of the invention as defined in the appended claims, as can be understood and carried out by those skilled in the art, from a study of the drawings, the disclosure and the attached claims. In the claims, the word "comprising" does not exclude other elements or stages, and the indefinite article "a" or "one" does not exclude a plurality. Even if certain features are mentioned in different dependent claims, the present invention also relates to an embodiment comprising these features in common. Any reference sign in the claims should not be construed as limiting the scope.

Claims (15)

1. A treatment plate (10) of an appliance for the treatment of garments (100), whose treatment plate has a contact surface that, in use, slides on a garment (30) that is being treated, characterized in that said contact surface is provided with a coating (20) comprising a metal oxide selected from the group consisting of titanium oxide, zirconium oxide, hafnium oxide, scandium oxide, or a mixture or combination thereof , and wherein said coating (20) has a thickness of less than 1 | jm. 2. A treatment plate according to claim 1, wherein the coating (20) is a sol-gel coating. 3. A treatment plate according to any one of claims 1-2, wherein said coating (20) consists substantially of (i) a titanium oxide, zirconium oxide, a mixture or combination of titanium oxide and Zirconium oxide, or a mixture or combination of titanium oxide and yttrium oxide. 4. A treatment plate according to any one of claims 1-3, wherein said coating (20) has a thickness of less than 400 nm. 5. A treatment plate according to any one of claims 1-4, wherein the treatment plate (10) comprises a metal substrate and wherein the treatment plate further comprises at least one layer disposed between said metal substrate and said coating (20), said layer which is a metal composition, a layer of enamel, organic polymer, organosilicate or silicate. 25 6. An appliance for treating garments (100), comprising a treatment plate (10) according to any of claims 1-5. 7. A process for producing a coating (20) on a contact surface of a treatment plate (10) of an appliance for the treatment of garments (100), in which, in use, said contact surface slides over a garment (30) that is being treated, and in which said coating (20) has a thickness of less than 1 jm, the process comprising the steps of: - depositing on said contact surface a layer of a precursor material of a metal or compound, selected from titanium, zirconium, hafnium, scandium or a mixture or combination of these metals or compounds, wherein the precursor material comprises one or more between a hydrolysable precursor and a hydrolyzable precursor solution; and - treating said layer to obtain a layer comprising titanium oxide, zirconium oxide, hafnium oxide, scandium oxide or a mixture or combination thereof. 8. A method according to claim 7, the method comprising the steps of: - depositing on said contact surface a layer of a hydrolysable precursor, preferably an alkoxide precursor or an acetate precursor, of a metal, selected from titanium, zirconium, hafnium, scandium, or a mixture or combination of these metals or compounds ; Y - curing said layer to obtain a layer comprising titanium oxide, zirconium oxide, hafnium oxide, scandium oxide or a mixture or combination thereof. 9. A process according to any one of claims 7-9, wherein said deposition is by means of a dry chemical process, preferably a vapor deposition process. 10. A method according to claim 7, the method comprising the steps of: - preparing a hydrolysable precursor solution, preferably of an alkoxide precursor or an acetate precursor, of a metal, selected from titanium, zirconium, hafnium, scandium, or a mixture or combination of these metals or metal compounds, - depositing on said contact surface a layer of said precursor solution, - followed by drying, if necessary, and curing to obtain a layer comprising titanium oxide, zirconium oxide, hafnium oxide, scandium oxide or a mixture or combination thereof. 11. A process according to claim 10, wherein said deposition is by means of a wet chemical process, preferably a dissolution process, more preferably a sol-gel process. 12. A process according to any one of claims 10-11, wherein the solvent used to prepare the solution of an alkoxide or acetate precursor of said metal is a lower alcohol, preferably ethanol, isopropyl alcohol, 2-butanol or 2-butoxyethanol. 13. A process according to any one of claims 10-12, wherein said alkoxide or acetate precursor is a propanolate or acetylacetonate derivative, and wherein said drying and curing is carried out at a temperature below 400 ° C. 14. A process according to any one of claims 7-13, wherein said contact surface of the treatment plate consists of a composition of metal, enamel, organic polymer, organosilicate or silicate. 15. A process according to any one of claims 7-10, wherein said contact surface is previously coated with at least one layer, preferably consisting of a metal composition, enamel, organic polymer, organosilicate or silicate , more preferably a metal oxide layer prepared by sol-gel techniques.