Decalcomania with transferable decorations in permanent manner and transfer process thereof on a surface

Description

[0001] The present invention concerns a decalcomania for the transfer, in a permanent manner, of a printed decoration on a surface.

[0002] A further object of the invention concerns the application process which utilizes said decalcomania to transfer the decoration printed thereon on a support.

[0003] The field of the invention is the one of transferable decalcomanias, that is to say of that technique which allows to apply on a pre-chosen surface, such as a wall made of masonry (brick, plaster, concrete, marble), wood, plastic, metal or cardboard, an industrial pre-printed decoration which is not hand painted.

[0004] The decalcomania of the present invention consists of a sheet of paper or of textile fibre as support, first coated with a coating solution or dispersion of substances of animal, vegetal or mineral origin, optionally modified or synthesized, then coated with a second coating of water or solvent soluble transparent synthetic resins on which the decoration (or image) is then printed according to any suitable known technology.

[0005] In particular, the first coating (patina) consists of colloid, starch, cellulose, resinous or similar substances and has the purpose to prevent the decoration from penetrating the fibres of the paper or of the textile fibre support, which would compromise the subsequent transfer on the chosen surface, while the second coating of water or solvent soluble transparent synthetic resins, once solidified, makes a surface suitable to receive the printing of the decoration.

[0006] Decalcomanias are already known in which the printed coating immediately dissolves when in contact with the water, so activating the superficial incorporated adhesive which fixes the decoration on the surface to be decorated; these decalcomanias are very sensitive to humidity and absolutely inadequate for the application on masonry walls, because the decoration, once transferred, is very fragile and is likely to move off the support because of the adhesive being inadequate.

[0007] It is also already known a decalcomania whose surface is treated with substances capable to resist to the action of cold water, while they dissolve in warm and damp ambient. This decalcomania allows the transfer of the decorations printed on the coating, using as a gluing material water soluble resins, which, once solidified, make possible the detachment of the paper by means of warm water or steam at a temperature higher than 70°C.

[0008] It is the object of the present invention to produce a decalcomania allowing to transfer the decoration on a surface easily, without the use of warm water or steam.

[0009] The present invention accomplishes this aim, and supplies also a transfer process which, by the use of the decalcomania herewith described, glued, by means of a transparent water soluble synthetic resin, on the surface to be decorated, allows to decorate a masonry or a wooden wall or any other surface even if not perfectly smooth or uniform, with a printed painting, which is characterized by a high affinity or likeness to craft made and hand made decorations.

[0010] The easiness of the transfer process of the decoration consists of the further detachment of the paper or the textile fibre support, once the glue has solidified and the decorated layer is permanently stuck on the support, upon soaking of the paper or the textile fibre support with water at ambient temperature, and not, as in the already known decalcomania, with hot water or steam at a temperature higher than 70°C, not easily available and handled.

[0011] Another characteristic of the decalcomania of the invention is represented by the coating of water or solvent soluble synthetic resins, which protects the underneath coating (patina) from scratches or abrasions, and allows to obtain, by applying any printing technology, a perfect print.

[0012] Besides preventing the coating of synthetic resins and the image printed thereon to penetrate the fibres of the paper or of the textile fibre support, the decalcomania has the property to resist to the action of the water at ambient temperature, maintaining its solid aspect, at least for the required processing time.

[0013] It should be pointed out that the first coating layer (patina) and the following coating of water or solvent soluble synthetic resins, once spread on the surface and solidified, remain bound each other and to the paper or to the textile fibre support surface without reciprocally penetrating, by means of a bond derived from their nature and from the density or the viscosity of the coating used.

[0014] This characteristic, once the gluing resin used for the transfer has solidified, allows the subsequent detachment of the paper or the textile fibre support by means of a light traction, upon soaking with water at room temperature, while the image and the protecting coating of synthetic resin remain perfectly stuck on the surface.

[0015] The layer of synthetic resin which initially served as a protection of the first coating and as a printing ground of the decalcomania image, when the transfer takes place, lies on the image layer, thus protecting it from abrasions, weather inclemency, and bleaching due to sun UV rays, without the need of a further protective varnish layer.

[0016] The paper or the textile fibre support used in the production of the decalcomania of the present invention, shows a surface permeable to water, but resistant to soaking, and it has very small fibres so providing a smooth surface, suitable, once coated with the protective resins, to be printed with the usual known technologies, such as offset, rotogravure, flexography, typography, serigraphy, or by computerized print by means of printers or plotters.

[0017] The first coating (patina), which has the function to prevent the subsequent coating layer of water or solvent soluble synthetic resins and the decoration printed thereon, from penetrating the paper or the textile fibre support, and consequently compromising the subsequent transfer, may be of different type: solutions or dispersions of colloid, starch, cellulose and resinous substances chosen among those substances resistant to the action of the water at room temperature and which remain compact without dissolving at least for the time for the process to be completed.

[0018] Examples of substances among the various possible ones, which may be used alone or in a mixture of two or more of them and suitable to be used are the following: gelatins, alginates, starches, dextrins, methylcellulose, ethylcellulose, carboxymethyl-cellulose or ureic resins, phenolic resins, Arabic gum or tragacanth gum.

[0019] The compounds which are comprised in the composition of the patina are not employed in critical quantities. In fact it is enough that the weight ratio among the various compounds be such to give to the compound dissolved in water the properties enabling it to be suitable to the application in a thin layer on the paper or textile fibre support.

[0020] Also the transparent synthetic resin both of water or solvent soluble type, forming the layer in contact with the patina, may be of different type: acrylic, vinylic, epoxy, polyurethane and similar, optionally as a mixture thereof.

[0021] The image used for the printing of the decalcomania of the invention is able to stick perfectly to the layer of the synthetic resin with the function of a support and, once printed, it resists to the action of the water without dissolving or coming off.

[0022] The water soluble transparent resin used as a gluing agent for the transfer of the decoration, is, preferably, of the type as the resin used as the coated resin layer in contact with the patina, and, it should, preferably, have the same opacity degree of the surface to be decorated. In particular the gluing agent can be select from acrylic, vinylic, polyuretane, epoxy resin, optionally as a mixture thereof.

[0023] The characteristics of the decalcomania object of the invention will be better described by means of some practical embodiments given as examples, but not as limitations thereof.

Example 1

[0024] The paper or the textile fibre support used in the production of the decalcomania is permeable to water and resistant to soaking without flaking off, and it has a weight, preferably, between 60 and 100 g/m².

[0025] The first coating material is made of starch that, once spread on the surface of the paper or textile fibre support, is water resistant at room temperature. The starch powder is dispersed in cold water, then the dispersion heated to the boiling temperature and mixed till obtaining a semi-transparent fluid.

[0026] After being coated with a thin and covering layer of starch, the paper or the textile fibre support is processed to the next protective coating by spreading on its surface a covering and homogeneous layer of a transparent acrylic resin solution, which, once dried, is permeable to water. On the so-obtained coating layer of acrylic resin, it is proceeded to the printing, with the printed decoration in a specular way, an optional micro-perforation of the decalcomania being provided before or after this operation.

[0027] The transfer process of a decoration on a surface, using the so obtained decalcomania is as following described.

- 1st process step.

[0028] The decalcomania, being formed by a paper or textile fibre support coated with the first starch layer and with a subsequent layer of water- or solvent-soluble synthetic resins, which may, optionally, be micro-perforated, then printed with the desired decoration, is soaked in a bath of water at room temperature. This operation has the purpose to soften and to lengthen the paper or the textile in order to give it the necessary flexibility to exactly match the profile of the surface to be decorated.

[0029] The preventive lengthening by soaking of the paper or of the textile fibre support has, in particular, the aim to avoid fold formations during the gluing step carried out with the water-soluble synthetic resins; otherwise it could be obtained an imperfect adhesion of the decalcomania to the new support.

- 2nd process step

[0030] The gluing material, consisting of a water-soluble transparent synthetic resin, is spread by brush or roll, as a covering homogeneous film, preferably, only on the surface to be decorated, on a size of slightly oversized dimensions than the area effectively covered by the decalcomania.

- 3rd process step

[0031] The surface of the decalcomania from the side of the printed decoration, is leant on the surface to be decorated, by gluing it thereon by means of the gluing material previously applied.

- 4^th process step

[0032] To remove the excess of the resin applied to the support and the possible air and glue bubbles which developed between the printed coating and the support itself, a gentle uniform pressure may be imparted on the interested surface using a small hair roll or a spatula, followed by the use of a sponge or absorbing paper. In this manner the remaining irregularities (bubbles, folds, resin excess and similar) are completely removed either laterally, or through the micro-perforation, if present.

5th process step

[0033] The decalcomania with the decoration well adherent on the surface to be decorated, is allowed to rest for the time necessary to the gluing material to harden, which time may vary according to the air temperature and humidity, however for a time little longer than one or two hours, if the weather is dry. This is made possible and explainable by the layer of water permeable synthetic resins on which the decoration is printed. The humidity contained in the gluing material, is brought by capillarity to the surface, through the paper or the textile fibre support and dried in contact with the air, so allowing the resin to harden.

6th process step

[0034] After the glue has stuck on the surface, it is proceeded to the removal of the paper or the textile fibre support to obtain the desired transfer of the image. To do so, the outward surface of the decalcomania is repeatedly soaked with water at room temperature, to spread it by capillarity through the fibres of the paper or of the textile fibre support to reach the patina. After a short time it will be possible to proceed for the detachment of the paper or of the textile fibre support, beginning from a corner, lifting it gently and pulling it with a light side traction.

[0035] It should be pointed out that, while in the first steps of the process preparation the image and the synthetic resin layer remained bound to the paper or to the textile fibre support when the decalcomania is soaked in water, in the present step, the image and the whole transparent synthetic resin layer are already perfectly anchored to the surface to be decorated and so the steeping together with the traction of the paper, permit to annul the remaining bound which still keeps the paper or the textile fibre support bound to the printed layer, so allowing its detachment.

[0036] Obviously, to the invention as above described and illustrated, it is possible to bring modifications to obtain variations which, however, are included in the scope of the following claims. So, for example the materials employed in the patina can be of any kind, provided that they are suitable to keep the layer of synthetic resin bound to the image, during the contact of the decalcomania with water at room temperature, and to easily release them after the transfer on the selected surface, by means of the subsequent steeping and light traction of the paper or of the textile fibre support.

[0037] In the same manner also the synthetic resins spread on the patina and those for the subsequent gluing on the surface to be decorated, could be different from those described, provided they are suitable to fix the image, together with the layer of the coated synthetic resin.

Claims

1. A decalcomania with decoration to be permanently transferred onto a suitable surface, characterized by the fact that it consists of a water permeable support which is resistant to water soaking and is coated with a first layer (patina),resistant to water at room temperature, which is formed by one or more suitable substances of animal, vegetal or mineral origin, optionally modified or synthetized, and with a second layer, lying over the patina, consisting of one or more water permeable transparent synthetic resins which are soluble in water or other solvents and that the decoration to be transferred is printed on the layer of synthetic resins by means of a suitable printing technology and is water resistant, being the decalcomania optionally micro-perforated before or after the decoration printing and the decoration resistant toward the water and the support, the patina and the synthetic resin layer each other bound without reciprocal penetration.

2. The decalcomania according to claim 1, wherein the water permeable support is selected from a sheet of paper and a sheet of textile fibre both being formed by small fibres.

3. The decalcomania according to claims 1 or 2, wherein the patina is formed by one or more substances selected from the group consisting of gelatin, alginates, starch, dextrin, methylcellulose, ethylcellulose, carboxymethylcellulose, ureic resins, phenolic resins, arabic gum and tragacanth gum.

4. The decalcomania according to the previous claims, wherein the water permeable transparent synthetic resins are selected from the group consisting of vinylic, acrylic, epoxy, polyuretane resins and a suitable mixture thereof.

5. The decalcomania according to the previous claims, wherein the water resistant decoration printed on the synthetic resins is printed by means of offset print, rotogravure, serigraphy, flexography, typography and by means of a computer operated printer or plotter.

6. A process for the transfer on a selected surface to be decorated of a decoration together with the layer of synthetic resins decorated utilizing the decalcomania according to the previous claims, characterized by the fact that said decalcomania is previously soaked with water at room temperature, then leant from the printed side on the surface to be decorated, previously coated with a layer of gluing water soluble synthetic resins, by means of a suitable pressure using a small hair roll or a spatula and removing, with absorbing paper or a sponge, the exceeding glue, so that, after the hardening of the glue and once a previous further soaking of the paper or textile fibre support, the latter is easily removed with a light traction.

7. A process according to claim 6, characterized by the fact that said gluing synthetic resin is selected from transparent acrylic, vinylic, polyurethanic, epoxy resins and similar, optionally as a mixture thereof.

8. The use of the decalcomania according to claims 1-5 for the permanent transfer of the printed synthetic resin layer on a selected surface to be decorated.