System and method for producing a permanent image and use of an application preparation for producing a permanent image

Abstract

The invention relates to a system for producing a permanent image, comprising an image template, comprising a first layer having at least one motif and a second hydrochromic layer arranged on the first layer, and an application preparation, wherein the application preparation comprises at least one first transparent liquid with a boiling point of more than 150 °C at an air pressure of 1000 hPa, and at least one second transparent liquid that is volatile at 25 °C and an air pressure of 1000 hPa.

Description

[0001] HOEFER & PARTNER

[0002] SSI250901 PCT-33 / BD

[0003] September 25, 2025

[0004] Applicant:

[0005] STABILO International GmbH

[0006] Schwanweg 1 90562 Heroldsberg

[0007] System and method for producing a permanent image and use of an application preparation for producing a permanent image

[0008] Description

[0009] The present invention relates to a system and a method for producing a permanent image, and to the use of a specific application preparation for producing a permanent image.

[0010] So-called water coloring books for children have been available commercially for many years. A water coloring book is understood to mean a coloring book in which images are produced by applying water. The images to be produced by water are initially invisible on the unused pages of the coloring book, but are covered by an opaque, usually white, matting hydrochromic layer that becomes transparent upon contact with water, thus revealing the image beneath the hydrochromic layer. The effect used in these coloring books is also known as the "wet reveal" effect, and hydrochromic inks can be purchased from companies such as "coates."

[0011] A disadvantage of commercially available systems with hydrochromic layers, such as, for example, the aforementioned coloring books, is that the effect of making the image or motif beneath the hydrochromic layer visible is temporary and only lasts until the applied water has evaporated. While this allows the coloring book to be reused, it cannot permanently produce the image underlying the system.

[0012] Furthermore, it was found that when using a high-boiling liquid instead of water to make the image or motif visible, an oily film forms on the surface of the then-transparent hydrochromic layer upon over-application and which film remains there, which can lead to contamination of the object or body part that comes into contact with the image during transport, storage, or even simply touching the hydrochromic layer, as well as to contamination of the image. Furthermore, high-boiling liquids are usually characterized by a high viscosity compared to water, making it difficult to spread the high-boiling liquid uniformly over the hydrochromic layer in a thin layer.

[0013] Based on this prior art, it is an object of the present invention to provide a system and method for producing a permanent image, which avoids an oil film formed by over-application and enables a uniformly thin application. Furthermore, it is an object of the present invention to specify a use for an application preparation. The objects are achieved by the features of the independent claims. The dependent claims contain advantageous refinements and configurations of the invention.

[0014] According to a first aspect of the present invention, this object is achieved by a system comprising an image template and an application preparation. The image template comprises a first layer and a second layer and may comprise further layers. The first layer is the layer that produces the final image. For this purpose, it comprises at least one motif, which can be of any shape, color, size, and configuration. In this case, two or more motifs combined can also be present in the first layer.

[0015] The second layer, which is designed in the form of a second hydrochromic layer, is arranged on top of the first layer. The second layer can partially or even completely cover the first layer. It acts as a matting layer, which is, in particular, opaque and thus has a whitish color, thus covering the motif(s) of the first underlying layer, so that the motif(s) are not visible in this state.

[0016] Within the meaning of the present invention, a hydrochromic layer is understood to mean a layer that changes its appearance from opaque to transparent upon contact with water. The second hydrochromic layer is formed in particular from a hydrochromic ink that is applied to the first layer or a transparent intermediate layer, and dried. Hydrochromic inks are commercially available, for example under the trade name PF 70 / 32 from coates. The second hydrochromic layer can also comprise motifs. However, this is not mandatory. In order to encourage the application of the application preparation, motifs are preferably also present in the second hydrochromic layer, which are intended to promote the application of the application preparation in specific areas of the second hydrochromic layer.

[0017] In contrast to conventional water coloring books, which use water, the system according to the invention comprises an application preparation. The application preparation comprises at least one first transparent liquid with a boiling point of at least 150 °C at an air pressure of 1000 hPa, and at least one second transparent liquid that is volatile at 25 °C and an air pressure of 1000 hPa. The higher the boiling point of the first transparent liquid, the more permanent the image is.

[0018] Within the meaning of the present invention, the first transparent liquid is understood to mean not only a liquid with a boiling point of at least 150 °C at an air pressure of 1000 hPa, but also a liquid with sufficiently high transparency. For this purpose, the first transparent liquid has, in particular, a transmittance of 0.02% to less than 100%. Transmittance is defined as the ratio of the transmitted light intensity to the incident light intensity and is measured photometrically with light with a wavelength between 400 and 800 nm, for example at 550 nm. The higher the transmittance, the higher the transparency of the liquid and the clearer the motif of the first layer appears beneath the then transparent second layer. Within the meaning of the present invention, the second transparent liquid is understood to mean any liquid or mixture of such liquids that are volatile at 25 °C and an air pressure of 1000 hPa. The second transparent liquid also has a sufficiently high transparency, i.e. , in particular, a transmittance of 0.02% to less than 100%, which is measured as stated above for the first transparent liquid.

[0019] What is important for the second transparent liquid is its volatility, which essentially distinguishes it from the first transparent liquid. A second transparent liquid used according to the invention is therefore understood to mean a liquid that has an evaporation number, measured according to DIN 53170, in a range of 5 to 90. The evaporation number is understood to mean the time a liquid requires to evaporate in relation to diethyl ether. The second transparent liquid therefore does not enable the production of a permanent image, but is essential for uniform application of the application preparation with a relatively thin layer thickness, and also for diluting the first transparent liquid, which is a high-boiling liquid, so that even in the event of over-application, no oily, greasy, or turbid film remains on the surface of the then transparent hydrochromic layer. The second transparent liquid thus dilutes the first transparent liquid, so that both transparent liquids together produce a very good, homogeneous application and a permanently clearly visible image / motif.

[0020] If the application preparation described above is applied to a surface of the second hydrochromic layer, the hydrochromic layer becomes transparent, thus losing its opacity or inherent color and thus also its matting effect, allowing the motif(s) of the first layer beneath the hydrochromic layer to be visible. Because the first transparent liquid has a boiling point of at least 150 °C, only the second transparent liquid evaporates, while the first transparent liquid remains on or in the surface of the second hydrochromic layer, creating the transparency of the hydrochromic layer, which is permanently maintained and thus also keeps the motif(s) of the first layer permanently visible.

[0021] The boiling point of the first transparent liquid is not specifically limited and can be as high as desired, as long as it is at least 150 °C, measured at an air pressure of 1000 hPa.

[0022] The first and second transparent liquids are otherwise not further limited. However, the transparent liquids should not contain any substances that could partially or fully dissolve the image motif in the first layer, as otherwise the image motif will "bleed" upon contact with the application preparation, making it harder to recognize.

[0023] The system according to the invention is characterized by a simple and efficient composition by which a prefabricated image comprising at least one motif contained in the first layer can be made permanently visible by homogeneous thin-layer application of the application preparation, without leaving an oily surface film.

[0024] According to an advantageous refinement, the application preparation is a single-phase preparation. Single-phase refers to a state in which the application preparation exists at 25 °C and an air pressure of 1000 hPa. No phase separation is visually detectable. This has the advantage that the application preparation can be produced using the simplest technical means and is not subject to decomposition or separation even during storage, thus ensuring the system has a very good shelf life.

[0025] The first transparent liquid preferably comprises a silicone oil and / or an ester oil. Silicone oils are characterized by high stability, particularly toward oxygen, thus ensuring the long-lasting stability of the system according to the invention. Ester oils also exhibit a relatively low tendency to oxidize and have the advantage over silicone oils that they are often obtained from renewable raw materials, thus improving the sustainability of the system. Both oil types are also characterized by high transparency and good spreading on different surfaces, thus allowing to further improve the spreadability of the application preparation.

[0026] Due to the high refractive index and thus very high transparency, the silicone oil is, in particular, a polysiloxane, which is advantageously selected from polydimethylsiloxanes, phenylsubstituted polysiloxanes, polyether-modified polysiloxanes, and mixtures thereof. In particular, the transparency of phenyl-substituted polysiloxanes, such as phenyl trimethicone, phenyl dimethicone, and the like, is particularly high. Polyether-modified polysiloxanes are characterized by improved miscibility with other "more polar" oils, i.e., ester oils, so mixtures of polyether-modified polysiloxanes are particularly advantageous when used in combination with ester oils. Unsubstituted and unmodified polydimethylsiloxanes can be obtained in different viscosities, so that their use is advantageous if the viscosity is not only to be set via the second transparent liquid, but the viscosity is to be shifted inherently into a range that is advantageous for a specific application device for applying the application preparation.

[0027] Due to its sustainability and environmental friendliness, the ester oil is particularly preferably selected from isopropyl myristate, isopropyl palmitate, jojoa oil, glyceryl esters, and mixtures thereof.

[0028] To form a system that is stable even at higher temperatures, such as those that can be used, for example, during storage or transport of the system according to the invention, the second transparent liquid is advantageously an alcohol or a mixture of alcohols. Alcohols are partially miscible, particularly with low-viscosity silicone oils, such as. In particular, dimethylsiloxane, which is miscible with isopropanol in any ratio, and also with ester oils, and they also have the advantage of preventing microbial growth, so that the system is further characterized by a permanently high shelf life, even after the application preparation has been opened.

[0029] For the aforementioned reasons, the alcohol is preferably selected from ethanol and isopropanol. In this case, any mixture of ethanol and isopropanol can also be used as the second transparent liquid.

[0030] According to an alternative advantageous refinement of the system, the first transparent liquid comprises glycerol and / or at least one glycol and / or one glycol ether and / or one glycol ester. Glycerol, glycols, glycol ethers, and glycol esters are inexpensive compounds available in various viscosities, are usually temperature- and oxygen-resistant compounds with high boiling points, and can also be selected accordingly depending on the chain length of the glycol. Due to the aforementioned advantages, preferred compounds are ethylene glycol, propylene glycol, butylene glycol, pentylene glycol, polyethylene glycol, polypropylene glycol, and poly(ethylene / propylene) glycol, each of which comprises all possible isomers.

[0031] Due to the excellent evaporation rate, the second transparent liquid is preferably selected from ethanol, isopropanol, water, and mixtures thereof. In particular, combinations of glycerin and / or at least one glycol and / or one glycol ether and / or one glycol ester as the first transparent liquid with water and / or, in particular, ethanol, isopropanol or a mixture of ethanol and isopropanol have proven to be an advantageous combination, since these substances are homogeneously miscible with one another over a very wide range, and the alcohol content can also prevent microbial growth of the application preparation.

[0032] To achieve permanently good image quality, it is advantageous if the proportion of the first transparent liquid in the application preparation is 30 and 80% by mass and, in particular, 40 and 70% by mass. The higher the proportion of the first transparent liquid, based on the total mass of the application preparation, the sharper and better permanently visible the image resulting from the first layer will be, however, the greater the risk that an oily film will remain on the surface of the second hydrochromic layer upon over-application of the application preparation. Furthermore, there is the possibility that the application will not be uniform and thin due to the high viscosity of the first transparent liquid, which in turn encourages the user to over-apply because the image is not initially produced equally well in all areas. However, if the proportion of first transparent liquid is low, i.e. less than 40% by mass and, in particular, less than 30% by mass, based on the total mass of the application preparation, the image cannot be made permanently visible with sufficient quality. It has therefore been found that the permanent image can be produced particularly well when the proportion of the first transparent liquid in the application preparation is 30 to 80% by mass, and in particular 40 to 70% by mass. If two or more first transparent liquids are used in the application preparation, the quantities stated here refer to the total quantity of all first transparent liquids. A further advantageous refinement provides that a proportion of the second transparent liquid in the application preparation, i.e. based on the total mass of the application preparation, is 20 to 70% by mass and, in particular, 30 to 60% by mass. The higher the proportion of the second transparent liquid, the better the spreading, i.e. the distributability of the application preparation on the hydrochromic layer by reducing the viscosity of the application preparation, and the lower the risk of over-application and thus the formation of an oily surface layer. However, the higher the proportion of the second transparent liquid in the application preparation, the lower the permanently good quality of the image produced. A very good compromise between homogeneous, uniformly thin application of the application preparation on the hydrochromic layer and very good permanence of a high-quality image is achieved when a proportion of the second transparent liquid, based on the total mass of the application preparation, is 20 to 70% by mass and, in particular, 30 to 60% by mass. If two or more second transparent liquids are used in the application preparation, the quantities stated here refer to the total quantity of all second transparent liquids.

[0033] For the aforementioned reasons, it is further preferred if a mass ratio of the first transparent liquid to the second transparent liquid in the application preparation is 4:1 to 1 :2.33.

[0034] According to a further alternative advantageous refinement, the application preparation is an emulsion. Within the meaning of the present invention, an emulsion is understood to mean an at least two-phase homogeneous dispersion in which one phase, the so-called inner phase, is distributed in droplet form in a continuous outer phase, wherein both the inner phase and the outer phase are liquid phases. O / W emulsions are generally common emulsions, in which an oil phase forms the inner phase and an aqueous phase or water phase forms the outer phase. Furthermore, there are also W / O emulsions, in which an aqueous phase or water phase forms the inner phase and an oil phase forms the outer phase. Furthermore, there are also multiple emulsions with three or more phases, such as, for example, a W / O / W emulsion or an O / W / O emulsion. It should be understood in this case that the term “oil phase” also refers to a phase that can comprise silicone oils and the like.

[0035] An emulsion as a form of application preparation has proven to be advantageous because it offers a stable application form between lipophilic and / or silicone oil-based substances, such as, in particular, polysiloxanes, and hydrophilic, aqueous and / or aqueous-alcoholic substances, which does not settle, can be easily stored and therefore enables long-term use.

[0036] Due to the very good distributability and lower viscosity, the emulsion is preferably an O / W emulsion, wherein “oil”, as already explained above, also comprises silicone oil or mixtures of different oils and silicone oils, all of which, however, meet the requirement of a boiling point of more than 150 °C at an air pressure of 1000 hPa. For reasons of high transparency and good emulsifying ability, the first transparent liquid preferably comprises at least one vegetable oil, a synthetic oil, a petroleum-based oil, an alcohol, a silicone oil, in particular a polysiloxane, or any mixture thereof. It should be understood that all substances specified here must also meet the requirement of a boiling point of more than 150 °C at 1000 hPa.

[0037] Among the aforementioned oil types, sunflower oil, rapeseed oil, linseed oil, walnut oil, olive oil, ester oils, such as, in particular, isopropyl myristate, isopropyl palmitate and jojoba oil, paraffin oils, polydimethylsiloxanes, phenyl-substituted polysiloxanes, polyether-modified silicone oils, aminoalkyl-substituted polysiloxanes and any mixtures thereof are preferred as the first transparent liquid.

[0038] In order to improve the spreading of the application preparation and to produce a permanent image as quickly as possible after application thereof, the second transparent liquid is preferably selected from ethanol, isopropanol, water and mixtures thereof, and is in particular water.

[0039] To stabilize the emulsion, particularly during storage or use at elevated temperatures, the application preparation advantageously further comprises at least one emulsifier, wherein the emulsifier, in particular, has an HLB value of at least 9. This can particularly effectively promote the formation of an O / W emulsion. The emulsifier may, depending on the type, be employed in appropriate ratios, which are ascertainable by routine experimentation.

[0040] To form a particularly stable emulsion that does not settle or separate, it is advantageous if a proportion of the first transparent liquid in the application preparation is 5 to 50% by mass, and, in particular, 10 to 40% by mass. If two or more first transparent liquids are used in the application preparation, the quantities stated here refer to the total quantity of all first transparent liquids.

[0041] To improve the distributability of the application preparation while maintaining high emulsion stability and simultaneously avoid the formation of an oily film due to over-application, the proportion of the second transparent liquid in the application preparation is preferably 50 to 95% by mass, and, in particular, 60 to 90% by mass. If two or more second transparent liquids are used in the application preparation, the quantities stated here refer to the total quantity of all second transparent liquids.

[0042] For the aforementioned reasons, it is further preferred if a mass ratio of the first transparent liquid to the second transparent liquid is 1 :1 to 1 :19. In order to promote the distributability of the application preparation and thus to be able to apply a uniformly thin but sufficiently large quantity of application preparation to the hydrochromic layer, the application preparation advantageously has a dynamic viscosity, measured at 25 °C by means of a Brookfield DV-1 rotational viscometer, in a range from 2 mPa ■ s to 40 mPa ■ s and, in particular, in a range from 3 mPa ■ s to 35 mPa ■ s.

[0043] In order to produce an image in a permanently particularly visible manner, the first layer advantageously comprises a plastic-based medium, a fiber-based medium or a textile-based medium. A plastic-based medium is understood, in particular, to mean media that are present in the form of a more or less thick layer or film. This can be, for example, packaging films but also items of clothing and parts thereof. A fiber-based medium is understood to mean media that comprise fibers of any type. The fibers can be synthetic, natural or nature-identical. Particularly common fiber-based media are fleece, paper and cardboard, with paper and cardboard, in particular, comprising cellulose fibers. Textile media are understood, in particular, to mean woven, braided, weft / warp-knitted or knitted media that are used, in particular, for items of clothing, furniture and home accessories. The materials used for this purpose are not specifically limited and can also be synthetic, natural or nature-identical.

[0044] The motif(s) of the first layer can preferably be applied to the plastic-based medium, the fiberbased medium or the textile-based medium described above. Printing processes such as, for example, offset printing are particularly suitable for this purpose. Printing processes produce the motifs with particular accuracy and permanent stability.

[0045] As already stated above, the configuration of the motif(s) of the first layer is essentially not limited. Preferably, the motif(s) is / are designed in one or more colors. This allows the motif to stand out particularly well from the medium of the first layer and also from the second layer, which is formed, in particular, with white or opaque color.

[0046] According to a further advantageous refinement, the second hydrochromic layer is formed from a dried hydrochromic ink applied to the first layer. In other words, a hydrochromic ink known in the prior art and commercially available can be used to produce the second hydrochromic layer, which forms the second hydrochromic layer after removal of any solvents by evaporation. "Removal by evaporation" here refers not only to the evaporation of solvents, but also to curing, such as, for example, curing with UV rays. Any method of fixing the second hydrochromic layer to the first layer is suitable.

[0047] Preferably, a hydrochromic ink usable for the present invention comprises at least one solvent, at least one binder, and at least one pigment for forming the second hydrochromic layer, wherein the binder can be selected from acrylic resins, alkyd resins, polyurethane resins, and polyester resins, and the pigment is selected from sodium aluminum silicates, amorphous silicas, clay, gypsum, aluminum oxides, talc (magnesium silicate), and metal carbonates. Preferably, no further pigments are included to improve transparency upon contact with the application preparation. Particle sizes of the pigments are preferably in a range of 1 to 35 pm. The particle size refers to the D50 value, which is measured by dynamic light scattering in suspension.

[0048] Particularly advantageously the hydrochromic layer is a layer applied by a screen-printing process, since the screen-printing process allows a suitable layer thickness of the hydrochromic layer to be set particularly well.

[0049] In order to expose the motif(s) of the first layer for a particularly long time and thus permanently through transparency of the second layer, the first transparent liquid preferably has a vapor pressure of less than 1000 hPa at 20 °C.

[0050] In order to be able to better distribute the application preparation on the second hydrochromic layer, the system according to the invention can further comprise an application device. To improve the distributability of the application preparation, the application preparation is preferably provided in a writing device or a painting device. The writing device or the painting device can thus be part of the system. For this purpose, the writing device or the painting device comprises, in particular, a reservoir that contains the application preparation and from which the application preparation can be conveyed for application. The reservoir can simply be a storage container in which the application preparation is present in an unbound state, or else a fiber reservoir. Suitable application devices therefore include, in particular, markers with a fiber reservoir and tip, "free ink" markers with a free application preparation in the tank and a valve system for dosing, or markers with a free application preparation in the tank with an associated compensation part for pressure and heat equalization. Alternatively, it is also possible to apply the application preparation with brushes, rollers, cloths, sponges, or the like.

[0051] To particularly effectively prevent the application preparation from flowing or spreading and thus promote the permanence of the produced image, the image template preferably comprises a barrier layer beneath the first layer or between the first layer and the second hydrochromic layer. Within the meaning of the present invention, a barrier layer is understood to mean a layer characterized by low porosity and low absorption capacity for the application preparation, so that the application preparation is not absorbed by the barrier layer and whose polarity is, in particular, contrary to the polarity of the application preparation.

[0052] The barrier layer can consist of a transparent material, such as, for example, polypropylene, PVC, polyester, and the like. The barrier layer prevents the application preparation, and, in particular, the first transparent liquid contained therein, from being absorbed by the substrate of the image motif, as this could compromise the permanence of the image. The barrier layer does not necessarily have to be present as a film. It is also conceivable to place a barrier layer above or below the image motif using printing techniques.

[0053] Advantageously, according to one embodiment, the system according to the invention also comprises a transparent film arranged between the first layer and the second hydrochromic layer. The transparent film can be designed as the aforementioned barrier layer, but can also be an alternative or additional transparent film. The use of a transparent film has the advantage that the hydrochromic layer can be applied directly to the film and can thus be produced in a separate step. Furthermore, the use of the transparent film in the production of the image template protects the motif of the first layer. A sufficiently high transparency of the film exists, in particular, when it has a transmission of 0.02% to less than 100%. Transmission refers to the ratio of the transmitted light intensity to the incident light intensity and is measured photometrically with light with a wavelength between 400 and 800 nm, for example at 550 nm. The higher the transmission, the higher the transparency of the film and the clearer the motif of the first layer appears beneath the then transparent second layer.

[0054] The material of the transparent film is not specifically limited. Due to their durability and mechanical stability, plastic-based films have proven particularly advantageous. Among these, in particular, polyolefin-containing, and among these, in particular, polypropylene-containing films or films comprising polypropylene copolymers, such as propylene / ethylene copolymers, are particularly preferred. This is due, among other things, to their permanent transparency, that is to say a low propensity for yellowing, thereby allowing the motif to stand out particularly clearly.

[0055] Due to electrostatic interactions, the transparent film may adhere between the first layer and the hydrochromic layer.

[0056] However, it is also advantageous if there is an adhesive layer between the transparent film and the first layer, or if the transparent film is designed to be self-adhesive on a surface facing the first layer. This enables a more stable bond between the first motif layer and the second hydrochromic layer.

[0057] If an adhesive layer is present, it preferably comprises an acrylate-based adhesive, a pressuresensitive adhesive, a hot-melt adhesive, or a light-cured adhesive. These adhesives are characterized by high user-friendliness, ease of use, and good adhesive properties and are therefore preferred.

[0058] Another aspect of the invention relates to a method for producing a permanent image. The method comprises a step of forming an at least two-layer image template comprising a first layer having at least one motif, and further comprising a second hydrochromic layer arranged on the first layer. Particularly suitable adhesives are PUR adhesives, polyolefin copolymers, and polyvinyl acetate adhesives, such as those sold under the trade name "Vinnapas" by Wacker AG, for example.

[0059] The second hydrochromic layer can be produced by using a hydrochromic ink. The hydrochromic layer can also be applied to a transparent film, which then acts as the barrier layer or transfer film for the hydrochromic layer described above. A second hydrochromic layer thus designed may then be joined to the first layer, for example using an adhesive or other bonding agent.

[0060] Then, an application preparation as described above, which comprises at least one first transparent liquid with a boiling point of more than 150 °C at an air pressure of 1000 hPa and at least one second transparent liquid that is volatile at 25 °C and an air pressure of 1000 hPa, is applied to the second hydrochromic layer.

[0061] In the areas where the application preparation is applied to the second layer, the opacity of the second layer changes to transparency, so that the motif(s) of the first layer located beneath the second layer and covered by the second layer become visible in these areas due to the transparency of the second layer.

[0062] The method is easy to apply without high technical effort and enables the production of a permanent image that is initially not visible in a creative way, wherein the method prevents the formation of an oil film on the surface of the second hydrochromic layer due to over-application by using the application preparation, and a uniformly thin layer of the application preparation is applied, which results in a high quality of the permanently produced image.

[0063] With regard to the advantageous configurations of the method, reference is additionally made to the system according to the invention. The advantageous refinements of the method according to the invention and the system according to the invention are mutually applicable.

[0064] A further aspect of the invention relates to the use of an application preparation as described above. The application preparation is used with the aim of producing a high-quality permanent image from an image template comprising a first layer having at least one motif, and a second hydrochromic layer arranged on the first layer, while avoiding the formation of an oil film on the second hydrochromic layer due to over-application of the application preparation. The image can be produced by the above-disclosed method according to the invention and thus by applying the application preparation.

[0065] The advantages, advantageous effects and refinements described for the system according to the invention, the method according to the invention and the use according to the invention are mutually applicable. Examples -

[0066] Below, a formulation is set forth for components for forming a first layer according to the invention and for components for forming a second layer according to the invention.

[0067] First

[0068] The first layer (motif-bearing) is a cardboard surface (white) printed with corresponding motifs using the following ingredients:

[0069] 10% by mass color pigment (e.g. HelioBeit LW 305, HelioBeit-LW 905 from Helio Beit, or others)

[0070] 30% by mass polymer dispersion Esacote AC 200 (from Lamberti surface treatment) 0.3% by mass defoamer BYK-019 (from BYK)

[0071] 2% by mass wetting agent DisperBYK-168 (from BYK)

[0072] 0-4% by mass RheoBYK-425 (for setting the rheology properties; from BYK) q.s.: water

[0073] Second layer:

[0074] 50% by mass Bayhydrol UV 2720 / 1 (from Covestro AG); aqueous UV varnish

[0075] 15% by mass Dorkafill H (kaolin; from Dorfner)

[0076] 15% by mass MinTalc 97-05 (talc; from Nobelmin)

[0077] 3% by mass Irgacure 500 (photoinitiator; from BASF)

[0078] 3% by mass Byk 348 (wetting aid; from BYK)

[0079] 0-3% by mass rheology additive to set the appropriate viscosity (see above) q.s.: water

[0080] The components of the second layer can optionally be mixed in a ratio of 10:1 (based on % by mass) with polyisocyanate (e.g. Bayhydur 305) to obtain a 2-component system with increased abrasion resistance.

[0081] In addition, the following application preparations 1 to 3 and a comparative application preparation were prepared. These were single-phase application preparations with varying proportions of polyethylene glycol 200 as the first transparent liquid and water as the second transparent liquid. The dynamic viscosity of the application preparations was measured, and the application properties were determined. Viscosity was measured by means of a Brookfield DV-1 measuring system (rotational viscometer) at room temperature.

[0082] The results are summarized in the following table: Of the application preparations 1 to 3, application preparation 2 was preferred due to the low viscosity and lowest stickiness of the hydrochromic layer after water evaporation. Furthermore, application preparation 2 was also very well suited for a fiber-tip applicator due to its low viscosity.

[0083] Application preparations 1 to 3 and the comparative application preparation were each applied to an image template comprising a first motif-containing layer and a second hydrochromic layer (prepared, for example, as in Example 1), specifically to the hydrochromic layer. In all cases, the motif of the first layer appeared after the hydrochromic layer had changed from being opaque to being transparent by application of the application preparation.

[0084] On the hydrochromic layer to which the comparison application preparation had been applied, a slight oil film was ultimately observed floating on the surface as a result of over-application due to non-uniform application.

[0085] No oil film was detectable on any of the other hydrochromic layers to which the application preparations according to the invention had been applied. However, the image produced by applying application preparation 3 was somewhat less intense than the other images obtained by applying application preparations 1 and 2.

[0086] Example 3

[0087] In addition, an emulsion-based application preparation was produced from the following raw materials:

[0088] A mixture of these raw materials was homogenized for 2 minutes using the highest setting of an Ultraturrax, resulting in a white, opaque emulsion of paraffin oil in water (O / W emulsion).

[0089] This application preparation in the form of an emulsion also demonstrated the permanent wet reveal effect when applied to an image template as used in Example 2. The mixture was also well suited for application with a brush, as the proportion of first transparent liquid was low, allowing a large portion of the application preparation to evaporate.

Claims

Claims1. A system for producing a permanent image, comprising:- an image template, comprising:- a first layer having at least one motif, and- a second hydrochromic layer arranged on the first layer- an application preparation, wherein the application preparation comprises:- at least one first transparent liquid with a boiling point of more than 150 °C at an air pressure of 1000 hPa, and- at least one second transparent liquid that is volatile at 25 °C and an air pressure of 1000 hPa.

2. The system according to claim 1 , wherein the application preparation is a single-phase preparation.

3. The system according to claim 2, wherein the first transparent liquid comprises a silicone oil and / or an ester oil.

4. The system according to claim 3, wherein the silicone oil is selected from polysiloxanes, in particular, from polydimethylsiloxanes, phenyl-substituted polysiloxanes, polyether-modified polysiloxanes, and mixtures thereof.

5. The system according to claim 3 or 4, wherein the ester oil is selected from isopropyl myristate, isopropyl palmitate, jojoa oil and glyceryl esters.

6. The system according to any one of claims 2 to 5, wherein the second transparent liquid is an alcohol or a mixture of alcohols.

7. The system according to claim 6, wherein the alcohol is selected from ethanol and isopropanol.

8. The system according to claim 2, wherein the first transparent liquid comprises glycerol and / or at least one glycol and / or one glycol ether and / or one glycol ester, in particular selected from ethylene glycol, propylene glycol, butylene glycol, pentylene glycol, polyethylene glycol, polypropylene glycol and poly(ethylene / propylene) glycol.

9. The system according to claim 8, wherein the second transparent liquid is selected from ethanol, isopropanol, water, and mixtures thereof.

10. The system according to any one of the preceding claims, wherein a proportion of the first transparent liquid in the application preparation is 30 to 80% by mass and, in particular, 40 to 70% by mass.

11. The system according to any one of the preceding claims, wherein a proportion of the second transparent liquid in the application preparation is 20 to 70% by mass and in particular 30 to 60% by mass12. The system according to any one of the preceding claims, wherein a mass ratio of the first transparent liquid to the second transparent liquid is 4:1 to 1:2.33.

13. The system according to claim 1 , wherein the application preparation is an emulsion.

14. The system according to claim 13, wherein the emulsion is an O / W emulsion.

15. The system according to claim 13 or 14, wherein the first transparent liquid comprises at least one vegetable oil, a synthetic oil, a petroleum-based oil, an alcohol, a silicone oil, in particular a polysiloxane, or any mixture thereof.

16. The system according to claim 15, wherein the first transparent liquid is selected from sunflower oil, rapeseed oil, linseed oil, walnut oil, olive oil, ester oils, such as in particular isopropyl myristate, isopropyl palmitate and jojoba oil, paraffin oils, polydimethylsiloxane, phenyl-substituted polysiloxanes, polyether-modified silicone oils, aminoalkyl-substituted polysiloxanes, and any mixtures thereof.

17. The system according to any one of claims 13 to 16, wherein the second transparent liquid is selected from ethanol, isopropanol, water and mixtures thereof and, in particular, is water.

18. The system according to any one of claims 13 to 17, wherein the application preparation comprises at least one emulsifier, wherein the emulsifier, in particular, has an HLB value of at least 9.

19. The system according to any one of claims 13 to 18, wherein a proportion of the first transparent liquid in the application preparation is 5 to 50% by mass and in particular 10 to 40% by mass.

20. The system according to any one of claims 13 to 19, wherein a proportion of the second transparent liquid in the application preparation is 50 to 95% by mass and in particular 60 to 90% by mass.21 . The system according to any one of claims 13 to 20, wherein a mass ratio of the first transparent liquid to the second transparent liquid is 1 :1 to 1 :19.

22. The system according to any one of the preceding claims, wherein the application preparation has a dynamic viscosity, measured at 25 °C, in a range from 2 mPa ■ s to 40 mPa ■ s, in particular from 3 mPa ■ s to 35 mPa ■ s.

23. The system according to any one of the preceding claims, wherein the first layer comprises a plastic-based medium, a fiber-based medium or a textile-based medium.

24. The system according to claim 23, wherein the motif is applied, in particular printed, to the plastic-based medium, the fiber-based medium or the textile-based medium.

25. The system according to any one of the preceding claims, wherein the motif is designed in one or more colors.

26. The system according to any one of the preceding claims, wherein the second hydrochromic layer is formed from a dried hydrochromic ink applied to the first layer.

27. The system according to claim 26, wherein the hydrochromic ink comprises at least one solvent, at least one binder and at least one pigment, wherein the binder is selected in particular from acrylic resins, alkyd resins, polyurethane resins and polyester resins, and wherein the pigment is selected from sodium aluminum silicates, amorphous silicas, clay, gypsum, aluminum oxides, talc and metal carbonates.

28. The system according to any one of the preceding claims, wherein the second hydrochromic layer is a layer applied by a screen-printing process.

29. The system according to any one of the preceding claims, wherein the first transparent liquid has a vapor pressure of less than 1000 hPa at 20 °C.

30. The system according to any one of the preceding claims, wherein the application preparation is provided in a writing device or a painting device.

31. The system according to any one of the preceding claims, wherein the image template comprises a barrier layer beneath the first layer or between the first layer and the second hydrochromic layer.

32. The system according to any one of the preceding claims, wherein a transparent film (4) is arranged between the first layer (1) and the second hydrochromic layer (3).

33. The system according to claim 32, wherein the transparent film (4) is a plastic-based film, which in particular comprises a polyolefin and in particular polypropylene or a copolymer of polypropylene.

34. The system according to claim 32 or 33, wherein an adhesive layer (5) is present between the transparent film (4) and the first layer (1) or wherein the transparent film (4) is designed to be self-adhesive on a surface facing the first layer (1).

35. The system according to claim 34, wherein the adhesive layer (5) comprises an acrylate-based adhesive, a pressure-sensitive adhesive, a hot-melt adhesive or a light-cured adhesive.

36. A method for producing a permanent image, comprising the steps of:- forming an image template with at least two layers, comprising:- a first layer having at least one motif, and- a second hydrochromic layer arranged on the first layer, and- applying an application preparation as described in any one of claims 1 to 22 to the second hydrochromic layer.

37. Use of an application preparation described in any one of claims 1 to 22 for producing a permanent image from an image template comprising a first layer having at least one motif and a second hydrochromic layer arranged on the first layer.

Images