NL2004360C2 - A COMPOSITION FOR IMPROVING VISIBILITY IN THE DARK AND A METHOD FOR MANUFACTURING SUCH A COMPOSITION. - Google Patents

Description

A COMPOSITION FOR IMPROVING VISIBILITY IN THE DARK AND A METHOD FOR MANUFACTURING A

SUCH COMPOSITION

The present invention relates to an assembly, in particular an assembly designed to improve the visibility of an image. The invention also relates to a method for manufacturing such an assembly and to the use thereof.

It is known to use signage signs, such as images used in the context of safety in the event of a calamity, for example fire in a building, which are still visible for some time even when it suddenly becomes dark so that they can continue to fulfill their signaling function. If, for example, the lighting goes out as a result of the calamity, the signaling may be designed such that it continues to illuminate for some time as a result of the use of luminescent material.

A known product with such a signaling is formed by plate material, for example a relatively stiff layer of vinyl, wherein on one side of the plate material is printed with paint or ink in which an amount of phosphorescent material has been applied. Phosphorescent material is material that when exposed, for example with outside light or with artificial light, continues to illuminate in the dark for a certain period of time. The afterglowing of the material is the result of the slowly falling back of electrons excited by irradiation with the light in the material. In order to provide the plate material with signaling, said paint or ink in which phosphorescent material is applied is marked with dark, often green (at least non-phosphorescent) ink. The parts that have not been treated with the dark ink are still visible in the dark for a short period, while the parts that have been treated with the dark ink are not or at least less visible. By a suitable arrangement of the parts that do and do not follow, the desired signage marks can be made visible in the dark. In order to increase the visibility of the signage signs, the plate material is provided in certain versions with a light, often white, surface. The white background provides a more visible area than a dark area (for example gray, black or green). Finally, a protective layer (laminate) is applied on top of 2 phosphorescent layer and the image. This layer protects the whole against external influences such as detergents, mechanical influences and / or influences as a result of sunlight.

However, there are a number of drawbacks to the known product. First of all, the plate material is relatively inflexible, so that the material cannot be applied properly to an irregularly shaped surface. The assembly of plate material and protective layer can only be less flexible than the plate material as such. In practice, the plate material can only be properly applied to a flat surface, which greatly limits the application possibilities of the product.

Since both the ink or paint containing the aforementioned phosphorescent material and the image itself are applied on top of one of the surfaces of the plate material, the assembly is relatively sensitive to external influences. The phosphorescent ink and the image can easily be damaged. This means that both the paint or ink and the image must be well protected against these influences. Protection of the assembly, however, requires additional material and effort, such as, for example, applying one or more protective laminate layers to the assembly.

A further drawback is that the manufacture of the product requires a relatively large number of manufacturing steps, namely applying the paint or ink containing the phosphorescent material, applying an image thereon (sign) and finally providing the whole with a protective laminate flooring.

A further drawback of the known product is that a special one must be manufactured for this purpose and that it is not possible to give an already existing image on any substrate the desired afterglowing properties. If, for example, signage signs are placed on a wall or an image, such as a photo, drawing and / or text, on a poster, it is no longer possible to have it light up in the dark. The signage on the wall or the poster must first be removed and replaced with a product specially prepared for this purpose. There is a need for an assembly that also makes it possible to have an existing image on a surface in the dark.

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It is an object of the present invention to provide an improved assembly and / or an improved method in which at least some of the aforementioned drawbacks are obviated. It is also an object of the invention to provide an assembly and / or method with which the desired optical properties can be given to an existing substrate (whether or not provided with one or more images) in a simple manner.

According to a first aspect of the present invention, an assembly is provided for this purpose, comprising: - a substantially transparent foil of plastic material, wherein phosphorescent material is arranged in the foil; - adhesive layer applied to one side of the transparent film for making the film self-adhesive.

The foil can be attached to any surface via the existing adhesive layer. The substrate can already be provided with an image and it is therefore possible to transform any ordinary image into a phosphorescent image. However, it is also possible to first provide the foil with an image and only then to apply the phosphor foil to the substrate. In the latter case, the image can be provided on the side opposite the said side to which the adhesive layer is applied, but it is also possible to first apply an image and only then to provide an adhesive layer over the image.

According to an embodiment, the assembly is designed to improve the visibility in the dark of an image on a surface to which the self-adhesive film can be adhered. By providing the phosphorescent layer on top of the substrate and the image provided thereon (text, figures, photos, symbols or the like), the image or the area around the image may light up in the dark so that the image remains partially or entirely visible .

To improve storage and transport of the assembly, the assembly in a further embodiment comprises a removable carrier, for example a removable cover layer or foil. The removable carrier is temporarily attached to the foil via the aforementioned adhesive layer. The assembly can be well stored and / or transported in this condition. In many cases, the assembly will have been put on a roll, but this is not necessary. If the film is to be used after the storage and transport phase (in the use phase), the removable carrier is removed. The film, removable carrier and adhesive layer are in this case designed to transfer the adhesive layer from the removable carrier to the transparent film when they are separated. This means that the foil becomes self-adhesive.

In certain embodiments, the transparent film is a calendered monomer film. In these embodiments, thermoplastic is heated and kneaded into an extruded sausage and then processed between two or more rollers into a cooled film of a certain thickness. The resulting film can be the end product, but it can also be a semi-finished product. After calendering, the foil can be further processed, for example by printing on it. The thickness of the films is typically between 100 and 500 µm. In embodiments of the invention, the side of the foil opposite the side of the adhesive material is made directly printable.

In the case that the image is applied to the transparent film itself, for instance when the film has the above-mentioned directly printable property, it can be advantageous to design the adhesive layer as a substantially light, more particularly white, adhesive layer. The parts of the foil that are not covered, for example by the image, then have a light (white) background. This ensures that the relevant parts are well-lit and therefore particularly visible in the dark.

If the image is printed directly on the foil or if the image is applied in any other way, it is often advisable to protect the image against external influences. In a further embodiment, the side with or without an image is provided with a transparent protective layer opposite the side of the adhesive layer. The protective layer is applied after one or more images have been applied to the printable side, for example images printed thereon with the aid of an ink-jet printer.

In other embodiments of the invention, the transparent film is a cast polymer film. During the casting process, phosphorescent material, for example phosphorescent pigment, is mixed with the polymer material to give the film the desired phosphorescent properties. In such a casting process 30 very thin films can be realized, typically with a thickness of between 50 and 90 µm. Due to their small thickness and / or due to their other material properties, these films are highly flexible and / or stretchable. This means that the film can be applied to any substrate and therefore also to a relatively irregularly shaped substrate. For example, it is possible to apply the foil over the lacquer layer of a vehicle, whether or not provided with images, such as a passenger car or truck. Due to its flexibility, the foil can fully follow the shape of the vehicle. With sufficient light, it is therefore (virtually) impossible to see that a film has been applied to the vehicle. However, when it suddenly becomes dark, for example when the vehicle ends up in a tunnel, the foil lights up, which gives a special effect.

The amount and composition of the phosphorescent material in the transparent film is selected such that the transparent film after an exposure with the usual light intensity for a period of time of more than 20 minutes.

The invention also includes the use of the assembly described herein. According to another aspect of the present invention, a method for manufacturing an assembly is provided for this purpose, the method comprising: - joining together plastic material and phosphorescent material; - manufacturing a substantially transparent phosphorescent film (laminate) from the combined material; - applying an adhesive layer on one side of the foil.

The application of an adhesive layer can herein comprise the following: - applying the adhesive layer to a removable carrier; - fixing the carrier to the said side of the foil via the adhesive layer; wherein the film, removable carrier and adhesive layer are designed to transfer the adhesive layer from the removable carrier to the transparent film in order to provide a self-adhesive film side.

According to a particular embodiment, the method comprises - manufacturing an intermediate consisting of a mixture of at least one monomeric material and phosphorescent material; - calendering the intermediate to provide a transparent film.

The foil material can be designed such that it is suitable for applying the image (s) directly thereto. One or more images can then be applied to the foil side opposite the side of the adhesive material. In a particularly advantageous embodiment, the foil side is directly printable and the method comprises printing the images on the foil, for example via an ink-jet printer known per se. After applying the images, a transparent protective layer is applied to protect the image against external influences, such as scratches, dust, dirt, UV radiation and the like. The protective layer not only provides physical protection for the image, but is usually also provided with UV absorbers or stabilizers to prevent the fading of colors of the image.

In other embodiments, the method comprises mixing phosphorescent material and liquid polymer material and casting the liquid mixture to form a cast film cast film. Such a foil can be made very thin. The foil is largely flexible so that it can also be adhered to a surface of a whimsical shape. Preferably, in the mixture of polymer material and phosphorescent material, materials are also added which ensure that the film can fulfill the function of the aforementioned protective layer. The film then has such properties that the image on the substrate is not only protected against external mechanical influences (such as scratches), but also, as a result of UV absorbers or stabilizers, against the influence of UV radiation and the like.

Further advantages, features and details of the present invention will be elucidated on the basis of the following description of some preferred embodiments thereof. Reference is made in the description to the accompanying figures in which:

Figure la shows a top view of a substrate provided with an image 25 in the form of a signaling arrow;

Figure 1b is a side view of the substrate with the signaling arrow;

Figure 2 shows a longitudinal section through an embodiment of an assembly 1 according to the invention;

Figure 3 shows a longitudinal section along the embodiment of Figure 2, wherein the cover layer 3 has been removed;

Figure 4a is a top view of the substrate with the signaling arrow of Figure 1a, provided with an embodiment of a foil according to the invention; 7

Figure 4b shows a longitudinal section through the substrate, signaling arrow and the embodiment of the invention, in the attached state;

Figure 5 is a longitudinal view of a second preferred embodiment of the assembly according to the invention, in the original state; and Figure 6 shows a longitudinal section through the second embodiment of the invention, in the position of use.

Figures 1a and 1b show a substrate (o), for example a wall or floor of a building, on which paints, inks or any other means, such as with the aid of a self-adhesive label or label, show an image (a) in the is provided in the form of a signaling arrow. In the embodiment shown, the image has a dark color, while the area (g) around the image is of light design. This area is preferably white and the image is designed in green, but other colors or shades of gray are also possible, provided that the material used (paint, ink, etc.) is sufficiently covering.

When the substrate is illuminated with sufficient (outside and / or inside) light, the signaling arrow is clearly visible. However, if the light goes out or it gets dark outside, visibility will decrease. In order to ensure that even with little or no light, the signaling arrow remains visible for some time, an embodiment of the assembly according to the invention is provided on the substrate and the signaling arrow.

Figure 2 shows a first embodiment of the assembly. Shown is a thin transparent foil 2, on a side 10 of which an adhesive layer 4 is applied. A removable cover layer 3 is provided on the opposite side 13 of the adhesive layer 4. The cover layer 3, also referred to herein as carrier or carrier layer, serves as protection of the assembly during storage and transport thereof and is preferably formed by a paper siliconized on at least one side. More generally, the carrier is designed in such a way that it is suitable on the one hand for supporting the adhesive of the adhesive layer or adhesive layer 4, but on the other hand binds the adhesive 30 (weakly) such that the adhesive can be transferred from the cover layer to the foil 2 when the cover layer 3 is removed. Any suitable adhesive or any suitable glue can be used for the adhesive layer, as long as they are compatible with the properties of the film 2 and enable the above-mentioned transfer 8. In the embodiment shown, the adhesive layer 4 is transparent.

As previously described, the foil 2 itself is also transparent or even crystal clear. In a preferred embodiment, the film is made of polymer material, for example a cast film, because the pigmentation can be mixed in in a more homogeneous manner. When manufacturing the film, the polymer material is first of all brought into liquid form. Phosphorescent pigments are then added to the liquid polymer material. The mixture is then poured onto a casting support and is plasticized and dried in the known drying ovens. This is the so-called "cast-film" process. The result of processing the mixture is a film with the desired mechanical and optical properties. The film can be made relatively thin, typically in the range of 50 to 90 µm. The foil can be called very flexible and can therefore be applied to any surface, but also when the surface has a erratic course, for example when the surface is formed by the paint layer on the outside of the lining of a motor vehicle.

In certain embodiments of the invention, the assembly of foil, adhesive layer and cover layer on roll is stored and transported. After a sufficiently large piece has been cut off from the assembly, i.e. a piece large enough to cover at least the signaling arrow (a) and the surrounding area (g), the cover layer 3 is manually peeled off from the rest of the assembly. Due to the properties of the cover layer (for example, because the cover layer 3 is provided with a siliconised side 13), the adhesive layer 4 will come loose from the cover layer 3 and only remain adhered to the foil 2. This state is shown in Figure 3. The foil 2 has hereby become a self-adhesive foil that is ready to be applied to a substrate.

Figures 4a and 4b show the state in which the foil 2 is attached via the adhesive layer 4 to the substrate and the signaling arrow (a) provided thereon. Because the adhesive layer 4 and the foil 2 are transparent, the signaling arrow (a) and the surrounding area (g) are still visible. When the film and the adhesive layer are sufficiently transparent, there is no or virtually no difference between the substrate with and without film under sufficient light. However, if the light intensity decreases, for example because the artificial light goes out for some reason 9, the presence of the phosphorescent material inside the foil 2 will continue to illuminate it for a certain time.

In the embodiment shown in which the signaling arrow (a) is of dark design and the surrounding area (g) is of light design, the surrounding area will now clearly light up in the dark and the area at the signaling arrow remains relatively dark. In this way the signaling arrow remains sufficiently visible even in the dark for some time. This means that if the light goes out, for example due to a calamity, the people present in the building are still pointed to the exit of the building via the arrow, for example. In the embodiment described above, the foil 2 is made of a cast foil consisting of, among other things, polymeric material. This foil is so flexible and thin that the foil can be applied over an existing substrate, without the substrate having to be flat. However, other embodiments are also possible. For example, it is possible to design the film as a monomer film. Such monomer films are generally thicker than the polymer cast films. They are produced by adding a quantity of phosphorescent material to the monomer material, mixing these materials and then extruding the mixture and then calendering until a film with the desired properties is achieved.

After this the aforementioned adhesive or adhesive layer 8 is applied (usually via a laminator). The choice of suitable adhesives and glues is clear to the skilled person. The adhesives or glues may preferably be white or opaque and may or may not be of such a composition that they can be transferred from a particular carrier material, for example silicone paper, to another carrier material, such as a crystal clear or transparent film. Known crystal-clear or transparent glues or adhesives can also be used, which are provided with white pigments or fillers in suitable amounts.

The monomer film can then be used in the same manner as described in connection with Figures 1a-4b, i.e. as a self-adhesive film that can be applied over an existing substrate. However, since a monomer film is thicker and less flexible, it is less suitable to be applied to a substrate of an irregular shape. Moreover, this foil has the disadvantage that it cannot be pasted over existing images since no image is visible anymore. However, the monomer film can also be used in other ways, such as is shown in Figures 5 and 6, for example.

Figure 5 shows the monomer film 6 which is provided with an adhesive layer 8 and a cover layer or carrier 17 in the aforementioned manner. However, in the embodiment shown, the adhesive layer 8 is a white or substantially white adhesive layer, so that the transparent film 6 on one side (side 16) has an even white background. On the other side (side 15), the foil 6 is provided with an image 9, for example (but of course not limited thereto), the aforementioned signaling arrow. This image can be applied in 10 different ways.

The image 9 can be produced by passing the whole of carrier 17, foil 6 and glue layer 8 through an ink-jet printer. Although the invention is not limited to certain types of ink or the number of colors thereof and only black ink or a single colored ink can be used, the invention is particularly suitable for making color images, such as printing photographs and the like. The basic colors yellow, magenta and cyan are generally used, possibly in combination with black ink. The use of a larger number of colors is of course also possible.

Once the image has been applied to the suitable side of the film, the ink is first allowed to dry. Once the ink has been sufficiently dried, a film is provided on the side on which also the image 9 is provided, which foil is provided with an adhesive or adhesive layer.

To protect the foil and in particular the image 9, a protective layer or cover layer 14 is provided over the side 15 and the image 9. The cover layer 14 ensures that the image is not or less exposed to external influences, such as mechanical influences, or the influence of incident sunlight.

Figure 5 shows the state in which the assembly can be brought on a roll for storage and / or transport. Usually the assembly is available on roll again, but in other cases the assembly is stored and / or transported in a different form. In order to place the whole on a surface, the carrier 17 can again be removed, so that the assembly, i.e. the foil 6, image 9 and possibly the cover layer 14, becomes self-adhesive. The (transparent or, preferably, white, glue layer) is, after all, designed in such a way that it remains on 11 surface 16 of the foil 6 and comes loose from the carrier 17. The assembly is now in the position of use shown in Figure 6 and can be applied in a known manner be adhered to a substrate (O).

Because the cover layer 14 is transparent, image 9 remains visible when it is light. When it gets dark, due to the presence of phosphorescent material in the film 6 itself, the film 6 will continue to emit light. In the embodiment shown, as a result of the presence of the white glue layer 8 behind the transparent foil 6, the entire area of the foil (at least where the white glue layer is located) will light up extra well. The light from the foil 6 can then leave the assembly via the cover layer 14. However, because the image 9 is provided, no light will be emitted locally so that the image 9 is recognizable as a relatively dark area. The image 9 can herein, for example, form the signaling sign so that in the dark the area around the signing sign lights up and the area at the signing sign remains dark. It is of course also possible to arrange the image 9 in a counter-shape so that the sign is formed by the area in which the image is not located. When it gets dark, the sign will now light up and the area around it (where the image is located) will remain dark.

The method of the invention and the self-adhesive film 20 thus obtained can be used, for example, for all known applications of inkjet techniques, such as making self-adhesive transparencies from photographs, drawings, graphic designs and the like, for example for use as decoration, logo, lettering and / or or for advertising purposes. The substrate on which the films can be applied can vary from vehicles, such as commercial vehicles, racing cars, boats, walls, floors, windows, banners, panels and the like.

The present invention is not limited to the preferred embodiments thereof described herein. The rights sought are rather determined by the following claims, within the scope of which many modifications are conceivable.

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Claims (21)

5 An assembly comprising: - a substantially transparent foil of plastic material, wherein phosphorescent material is arranged in the foil; 10. adhesive layer applied to one side of the transparent film for making the film self-adhesive. 2. Assembly as claimed in claim 1, wherein the assembly is designed for improving the visibility in the dark of an image on a surface 15 on which the self-adhesive film can be adhered. 3. Assembly as claimed in claim 1 or 2, further comprising a removable carrier provided with the adhesive layer, wherein the foil, removable carrier and adhesive layer are designed to transfer the adhesive layer from the removable carrier to the transparent foil upon separation thereof so that the foil becomes self-adhesive. Assembly as claimed in any of the foregoing claims, wherein the transparent film is a calendered monomer film. Assembly as claimed in any of the foregoing claims, wherein the adhesive layer comprises a substantially white adhesive layer. Assembly as claimed in any of the foregoing claims, wherein the side of the foil opposite the side of the adhesive material is directly printable. 30 An assembly according to any of claims 4-6, wherein the thickness of the film is between 100 and 500 µm. Assembly as claimed in any of the foregoing claims, wherein on the side printed or not opposite the side of the adhesive layer, the transparent foil is provided with a transparent protective layer. An assembly according to any of claims 1-3, wherein the transparent film is a cast polymer film wherein phosphorescent material has been added to the polymer material during the casting process. An assembly according to claim 9, wherein the thickness of the film is between 50 and 90 10 µm. An assembly according to any one of the preceding claims, wherein phosphorescent material is designed in the transparent film to at least partially after exposure for a period of time of more than 20 minutes. 15 An assembly according to any one of the preceding claims, wherein the phosphorescent material comprises pigment mixed with the polymer material. 13. Use of the assembly according to any of the preceding claims, wherein the self-adhesive film is adhered to a substrate. An object, in particular a vehicle, provided with a lacquer layer, wherein the substrate is formed by lacquer layer and a self-adhesive phosphorescent film according to one of the preceding claims is adhered to the lacquer layer. 25 A method of manufacturing an assembly, preferably the assembly according to any of claims 1-12, the method comprising: - joining together plastic material and phosphorescent material; - manufacturing a substantially transparent phosphorescent film from the combined material; - applying an adhesive layer on one side of the foil. A method according to claim 15, wherein applying an adhesive layer comprises: - applying the adhesive layer to a removable support; - fixing the carrier to the said side of the foil via the adhesive layer; wherein the film, removable carrier and adhesive layer are designed to transfer the adhesive layer from the removable carrier to the transparent film in order to provide a self-adhesive film side. 10 A method according to claim 15 or 16, comprising: - manufacturing an intermediate consisting of a mixture of at least one monomeric material and phosphorescent material; - calendering the intermediate to provide a transparent film. The method of claim 17, wherein the adhesive layer comprises a substantially white adhesive layer. A method according to claim 17 or 18, comprising applying one or more images on the foil side opposite the side of the adhesive material, preferably printing the images on said foil side. 20. Method as claimed in any of the claims 17-19, comprising of applying a transparent protective layer to the side with or without images. A method according to any of claims 15-16, comprising: - mixing phosphorescent material and liquid polymer material; 30. pouring the liquid mixture to form a cast film.