FR3034783A1 - PAPER-PAINTED PREENCOLLE - Google Patents

Abstract

The wallpaper (1) according to the invention comprises a support (2) comprising cellulose and / or polyester, with a thickness of between 100 μm and 500 μm. The support (2) is covered with a first layer (3) positioned on a first face (2a) of the support (2), and comprising glue. The support (2) is advantageously constrained in compression by means of the first layer (3), so as to prevent variations in dimensions of the wallpaper (1) after laying. The wallpaper (1) is also covered with a second layer (4) positioned on a second face (2b) of the support (2) opposite to the first face (2a), and configured to allow the deposition of a layer inkjet printing. The invention also relates to the method of manufacturing a wallpaper (1) as just described.

Description

TECHNICAL FIELD OF THE INVENTION The invention relates to a pre-glued wallpaper that can be washable or not, and possibly fire resistant. State of the art Wallpapers are conventionally used as ornaments for walls. The latest printing technologies now make it possible to produce wallpapers at the customer's request, for example from one of his photos. For this purpose, inkjet prints are made on the wallpaper strips, so as to obtain for example a photo occupying the entire space of a wall. However, the application of the wallpaper requires great dexterity for the result to be successful. If the layer of glue deposited on the wallpaper is not uniform, it can lead to a poor quality result, for example by forming glue blisters or air bubbles between the wall and the wallpaper. Furthermore, if the room in which the wallpaper is laid is subject to variations in temperature and / or humidity, this may lead to variations in width of the strips during drying, and therefore to the appearance of white stripes between the strips. The customer can only be disappointed by the result.

SUMMARY OF THE INVENTION In order to guarantee easy and unsurprising application of the wallpaper, it is an object of the invention to produce a pre-glued wallpaper comprising: a support comprising cellulose and / or polyester, of a thickness between 100 μm and 500 μm, a first layer positioned on a first face of the support, and comprising glue, a second layer positioned on a second face of the support opposite to the first face, and configured to allow the deposition of an inkjet printing layer. The first layer advantageously constrains the compression support 15 so as to prevent variations in the dimensions of the wallpaper after laying. The invention also relates to the method of manufacturing a wallpaper having the above characteristics. The manufacturing method comprises the following steps: providing a support comprising cellulose and / or polyester, having a thickness of between 100 microns and 500 microns, depositing a first mixture on a first face of the support so as to form a first layer, the first mixture comprising a wettable activatable adhesive, drying the first layer so as to constrain the support in compression to prevent variations in the dimensions of the wallpaper after laying, depositing a second mixture on a second side of the support Opposed to the first face so as to form a second layer, the second layer being configured to allow the deposition of an inkjet printing layer, drying the second layer.

Other advantages and features will become more clearly apparent from the following description of particular embodiments of the invention given by way of nonlimiting example and represented in the accompanying drawings, in which: FIGS. 1 and 2 schematically illustrate sectional views of two embodiments of a pre-glued wallpaper; - Figure 3 illustrates the method of manufacturing said wallpaper.

DETAILED DESCRIPTION A wallpaper 1 such as that shown in FIGS. 1 and 2 is made from a support 2 made of cellulose and / or polyester having a thickness of between 100 μm and 500 μm. The disadvantage of this type of material is that it may be subject to dimensional variations when it is subjected to changes in temperature and / or hygrometry, particularly with regard to the length and width of wallpaper. Therefore, it is possible that the wallpaper 1 retracts once laid, giving a result to say the least unsightly. In order for the wallpaper 1 to have more stable dimensions, it may be envisaged to use a non-woven support 2 made of cellulose and polyester fibers bonded together by means of a synthetic latex.

For good dimensional stability, an object of the invention is to constrain the support in compression, so as to prevent variations in its dimensions after manufacture, and in particular during laying. To achieve this, a first layer 3 comprising glue is deposited on a first face 2a of the support 2. The first layer is made from a first mixture of synthetic latex and an adhesive which may for example be adhesive. Eukalin® 2472, Eukalin® 4447, Eukalin® 2457 EG, or Encor® 4366. These adhesives 10 have the advantage of being easily reactivated by humidification, for example by means of a water spray. The thickness of the adhesive layer is advantageously between 25 and 50 μM. This range of thickness is preferred because it makes it possible to respond to several antagonistic constraints. The glue layer should be thick enough so that the wallpaper is properly glued, and can be repositioned before the glue is dry. The layer of glue must not be too thick because it must dry quickly.

The cellulose and / or polyester support 2 alone does not provide good print quality when using an ink jet printer. Also, to remedy this problem, a second layer 4 is deposited on a second face 2b of the support 2 to allow the use of the wallpaper 1 in the context of an inkjet printing. The role of the second layer 4 is to fix the print on the wallpaper 1 to have a high quality rendering and longevity. According to a first embodiment of the wallpaper 1 illustrated in FIG. 1, the second layer 4 may for example be made from a second mixture comprising from 600 g to 1 kg of water and a powder comprising 50 200 g of mineral powder, 30 to 100 g of synthetic latex, 5 to 40 g of polyvinyl alcohol polymer, and 3 to 10 g of cationic polymer. The second mixture may for example comprise 100 g of water, 30 g of precipitated calcium carbonate such as Omyabrite®, 30 g of synthetic latex such as DL9300, 30 g of polyvinyl alcohol at 15% solids, and 2 g cationic polymer such as Marefix ze. To form the second layer, it is also possible to use a second mixture comprising 100 g of water, 25 g of silica such as Gazil 23 F 0, 10 g of Cartacoat B6340, 10 g of polyvinyl pyrrolidone, 40 g of 15% polyvinyl alcohol, % of dry extract, and 5 g of cationic polymer such as catiofast BP3Og of polyvinyl alcohol with 15% solids, and 2 g of cationic polymer such as Catiofast BPO.

According to one particular embodiment, the second mixture may be composed of 800 g of water, 100 g of silica, 40 g of styrene-butadiene polymer, 30 g of polyvinyl alcohol polymer, and 6 g of cationic polymer.

Each element of the powder used to make the second mixture plays an important role in ensuring the quality of the inkjet printing. The inorganic powder absorbs the water of the aqueous inks deposited on the second layer 4. The polyvinyl alcohol polymer and the synthetic latex serve as a binder in the second mixture and allow the prints to be made from latex inks and dyes. aqueous inks. The cationic polymer contributes to the coagulation of the pigments of the ink. Indeed, the pigments being anionic, they agglomerate on the surface of the second layer on the cationic polymer, which allows to obtain bright colors.

The mineral powder may be silica, and / or calcium carbonate, and / or kaolin and / or talc. However, silica and / or precipitated calcium carbonate, and generally any inorganic filler with a high specific surface area are preferred. With this type of material, the wallpaper 1 5 is directly manipulable printer output because the water of the ink is absorbed by the second layer while the pigment ink remain on the surface. If the mineral powder used is kaolin and / or talc, the water of the ink is not completely absorbed and the wallpaper 1 can not be handled immediately.

The synthetic latex used in the second mixture may be selected from styrene-butadiene latex, vinyl latex, acrylic latex and polyurethane latex. The first three types of latex have the advantage of being inexpensive and having a high tackiness. The cost of polyurethane latex is greater but this material has the advantage of being more fire resistant than the other three materials. The use of the polyurethane latex in the second layer as a binder makes it possible to obtain a combustible but non-flammable wallpaper 1 after having been laid. These properties can be the subject of an M1 classification within the framework of the French standard NF P92-507. The proportions of inorganic powder on the one hand and synthetic latex on the other hand are adapted to both allow printing with aqueous inks or latex. Indeed, if the amount of synthetic latex in the second mixture is too great, it becomes impossible to print with an aqueous ink because the water of the ink is no longer properly absorbed by lack of silica and / or carbonate of calcium.

The proportions of mineral powder and synthetic latex are also adapted according to the specific surface area of the mineral powder. In fact, the greater the specific surface area of the mineral powder, the more synthetic latex is required to bind the inorganic powder particles. For comparison, an equal amount of mineral powder requires 5 to 8 times more synthetic latex to bind silica than to bind calcium carbonate.

The thickness of the second layer 4 may advantageously be between 10 and 30 μm and preferably between 15 and 30 μm. This range of value makes it possible to have a good quality of printing (sharpness, bright colors, etc.). It is also fine enough so that the cost of wallpaper 1 is not prohibitive. According to an alternative embodiment, the wallpaper 1 may be washable. In this case, the use of an aqueous ink is discouraged. It is best to use a latex ink or a solvent ink.

For this, the second layer 4 may advantageously have hydrophobic properties. The second mixture used to make the second layer 4 can for example comprise 400 to 800 g of water, 50 to 150 g of mineral powder, 100 to 300 g of synthetic latex, and optionally 1 to 2 g of additives (surfactant, thickener , etc.). According to a particular embodiment, the second mixture may be composed of 600 g of water, 100 g of calcium carbonate, and 200 g of acrylic binder.

Acrylic latex is preferred in this embodiment because it self-crosses very easily. The styrene-butadiene latex, the acrylic latex and the polyurethane latex also make it possible to obtain sufficient hydrophobicity for the wallpaper 1 to be washable. The acrylic latex also has the advantage of being more resistant to yellowing than styrene-butadiene, and of being less expensive than a polyurethane.

The coagulation of the pigments of solvent inks and latex inks can be carried out without resorting to a cationic polymer. Indeed, the size of the pigments used in latex inks and solvent inks is much smaller than that of aqueous inks. The presence of a cationic polymer in the second mixture is therefore not necessary when the wallpaper 1 is for a latex or solvent printing. As for a non-washable paper, the characteristic thickness of the second layer 4 in the case of a washable wallpaper 1 may be between 15 and 30 microns with the same advantages as before. In order for the washable wallpaper 1 to be fire-resistant, a third layer 5 may be deposited on the second face 2b of the support 2. More specifically, the third layer 5 may be placed between the support 2 and the second layer 4. This third layer is advantageously produced by means of a third mixture comprising a flame retardant. This embodiment is illustrated in Figure 2. Alternatively, the second layer 4 may be formulated with a flame retardant. The flame retardant may also be present in both the second and third layers 4 and 5. The third mixture may be an aqueous solution made from nitrogen and phosphorus. These two materials have a high fire resistance, and allow the realization of a fireproof but non-flammable wallpaper 1 when installed. The flame retardant introduced into the second and / or third mixtures may be based on organic phosphorus compounds such as Pekoflam HFCO or Pekoflam TC 203® marketed by Arkroma.

The flame-retardant compound is preferably bonded with a small amount of binder so as not to decrease its fire resistance. Also, for 100g of Pekoflam TC2030 present in the third mixture, the latter can comprise 20g of Cartacoat B6340.

For aesthetic reasons, the third mixture may also include a white pigment such as titanium dioxide to increase the whiteness of the support 2.

The thickness of the third layer 5 may advantageously be between 10 and 30 μM. This range of thickness makes it possible to produce a wallpaper 1 having good fire resistance. To manufacture the wallpapers 1 just described, a machine 6 such as that illustrated in Figure 3 is employed. It serves to deposit the first, second and third layers 3, 4 and 5 on the support 2 in one or more times. The machine 6 comprises an entrance area 6a in which the support 2 is unrolled, and an exit zone 6b in which the wallpaper 1 is wound after the various layers have been deposited on the support 2. The machine 6 comprises an oven 7 through which the support 2 can scroll. The oven 7 is intended to dry the various layers after their deposition on the support 2.

The machine 6 also comprises cylinders 8, and advantageously as many cylinders 8 as layers to be deposited on the support 2. The rotation of the cylinders 8 allows the carrier 2 to be scrolled from the entry zone 6a of the machine 6 to the exit zone 6b. In a variant, the rolls are passive and their driving is carried out by moving the support.

Before each cylinder 8 is a deposition device 9 of each layer to be deposited on the support 2. Each deposition device 9 comprises a tank 9a in which the mixture used for the deposition is deposited, a roll 9b dipping in part in the mixture, and scrapers which are preferably formed by air strips 9c for removing excess mixture deposited on the support 2. According to the embodiments, the roller 9b can be active and therefore motorized or passive and therefore driven by the support 2. Each roller 9b can be rotated in the running direction of the support 2, or in the opposite direction to obtain a better spread of the mixture. In order to produce a wallpaper 1 having a first layer 3 on a first face 2a of the support 2 and a second layer on a second face 2b of the support 2, the support 2 is unwound in the zone 6a of the machine, positioned in the machine and placed in zone 6b so as to be ready to be wound. In a first deposition device 9, the first mixture comprising activatable adhesive by humidification is placed in a first tray 9a. A first roll 9b coats the lower face which is here the first face 2a of the support 2 with the first mixture, and first scrapers, preferably first air blades 9c, remove the surplus.

The air flow leaving the first blades 9c is chosen so that the amount of the first mixture deposited on the support 2 is between 25 and 50 g / m 2. The temperature of the air emitted by the blades can advantageously be between 10 and 30 ° C, and preferably be equal to the temperature of the room where the wallpaper 1 is manufactured.

Following the first deposition device in the direction of travel of the support 2 is a first cylinder 8. The rotation of the cylinder 8 has the effect of scrolling the support 2, and the first face 2a initially corresponding to the bottom face of the support 2 is now the upper face 5 of the support 2. The support 2 coated with the first mixture then passes through the oven 7, which has the effect of drying the first mixture to form a first layer 3. On drying, the first The mixture containing the glue 10 advantageously compresses the support 2 in compression, so that the dimensions of the latter remain fixed regardless of the variations in hygrometry or temperature thereafter. According to the embodiments, the furnace 7 can be placed after the cylinder 8 or between the first deposition device 9a, 9b and the cylinder 8. At the outlet of the furnace 7 is a second deposition device 9 making it possible to carry out the depositing the second mixture on the second face 2b of the support 2, which corresponds to the underside at this stage of implementation of the process. The second mixture is deposited in a similar manner to the first mixture. The second mixture is placed in a second tank 9a and deposited on the second face 2b of the support 2 with a second roller 9b. A flow of air emitted by second air blades 9c makes it possible to remove the surplus of second mixture deposited on the support 2. Here, the air flow rate is chosen so that 10 to 30 g / m 2 and preferably 20 to 25 g / m 2 of second mixture is deposited on the support 2. The air flow may advantageously have a temperature between 10 and 30 ° C.

A second cylinder 8 placed downstream of the second deposition device 9 causes the support 2 to be turned back so that the latter passes again through the oven 7 or another oven set for example at another temperature. This makes it possible to dry the second mixture, which becomes the second layer 4. Following the first deposition device in the direction of travel of the support 2 is a first cylinder 8. The rotation of the cylinder 8 has the effect of making scroll the support 2, and the first face 2a corresponding initially 10 to the lower face of the support 2 is now the upper face of the support 2. At the outlet of the furnace 7, the support 2 on which the first and second layers are deposited form a wallpaper 1 which is wound in the exit zone 6b of the machine. In the case where the wallpaper 1 has 3 layers, that is to say when it is washable and fire resistant, it is preferable to first deposit the third layer 5 located on the second face 2b of the support 2, then the first layer 3 located on the first face 2a of the support 2, then the second layer 4 on the third layer 5. This method of making the wallpaper 1 is illustrated in Figure 3. A filing order different layers on the support can also be adopted.

The alternating deposition of layers on a first face 2a and then on a second face 2b of the support is preferred because it makes it possible to limit the size and / or the complexity of the machine 6. In fact, if two layers were to be deposited successively on the same side, it would be necessary to add at least one additional cylinder 8 so that the face 30 corresponding to the lower face of the support 2 is twice the same. However, it may be useful to deposit the first layer 3 comprising the glue first, so that it passes several times through the furnace 7 and by the same increase the compressive stress of the support 2. According to the mode of implementation 3, the third layer 5 is deposited first on the second face 2b of the support 2. As in the first embodiment of the wallpaper 1, the third layer 5 is deposited on the underside of the support with the aid of a deposition device 9. A roll 9b impregnates the second face 2b of the support 2 of the third mixture, then the excess mixture is removed with the aid of a flow of air emitted by air knives. The air flow is advantageously chosen to keep only 10 to 30 g / m 2 of third mixture on the second face 2b of the support 2. The air flow may advantageously have a temperature between 10 and 30 ° C.

A cylinder 8 placed just downstream of the air knives and rotated makes it possible to turn the support 2 so that the third layer 5 is now positioned on the upper face of the support 2. The first layer 3 comprising glue is then deposited on the first face 2a of the support 2 now corresponding to the lower face of the support 2. The deposition mode of the first layer 3 is similar to that described in the first embodiment described above. The second layer 4 is finally deposited above the third layer 5 according to the method described above. To achieve the deposition of the different layers on the support 2, and in particular to achieve the deposition of the first layer 3 comprising the glue, the machine 6 is advantageously configured to scroll the support 2 30 at a speed below 15 m / min . If carrier 2 is traveling at a higher speed, the first mixture might not be deposited uniformly on carrier 2 because of its high viscosity. The quality of the wallpaper 1 and the final result once it is set could be unsatisfactory for the user.

If the machine used is able to scroll the support 2 at different speeds, it is possible to deposit the second and third layers at a speed of between 50 and 70 m / min, preferably equal to 60 m / min. On the other hand, the deposition of the first layer comprising the adhesive must be carried out at a speed of less than 15 m / min.

Furthermore, to achieve optimum drying of the various layers deposited on the support 2, the oven is preferably maintained at a temperature between 90 and 250 ° C, and preferably between 150 and 200 ° C. The running speed of the support 2 and the dimensions of the oven 7 are such that each layer is present in the oven 7 for a period of between 5 and 20 seconds. With these ranges of temperature and drying time, each layer deposited on the support 2 and out of the oven 7 is dry on the surface, which allows the handling of the support 2 without damaging it.

Once the manufacture of the wallpaper 1 is completed, the latter may finally undergo calendering (not shown) in order to have a smoother and brighter appearance if such properties are desired. 25

Claims (19)

REVENDICATIONS1. Wallpaper (1) comprising: a support (2) comprising cellulose and / or polyester, of a thickness of between 100 μm and 500 μm, a first layer (3) positioned on a first face (2a) of the support (2), and comprising glue, a second layer (4) positioned on a second face (2b) of the support (2) opposite to the first face (2a), and configured to allow the deposition of a layer of inkjet printing, characterized in that the first layer (3) constrains the support in compression so as to prevent variations in the dimensions of the wallpaper (1) after the laying. 2. Wallpaper (1) according to claim 1, wherein the second layer (4) comprises polyurethane so as to obtain a fire-resistant wallpaper (1). Wallpaper (1) according to any one of claims 1 or 2, wherein the second layer (4) comprises a flame retardant. 4. Wallpaper (1) according to any one of claims 1 or 2, comprising a third layer (5) positioned between the support (2) and the second layer (4), the second and / or the third layer ( 5) having a flame retardant. The wallpaper (1) according to claim 4, wherein the third layer (5) comprises a white pigment such as titanium dioxide. 6. Wallpaper (1) according to any one of claims 4 or 5, wherein the second layer (4) comprises a hydrophobic agent so as to allow the deposition of a latex ink layer or solvent ink on the second layer (4). 7. Wallpaper (1) according to claim 6, wherein the hydrophobic agent 5 is selected from acrylic, styrene-butadiene, and vinyl. The wallpaper (1) according to any one of claims 4 to 7, wherein the third layer (5) has a thickness of between 10 and 30 μM. 10 Wallpaper (1) according to any one of claims 1 to 8, wherein the first layer (3) has a thickness of between 25 and 50 μM. The wallpaper according to any one of claims 1 to 9, wherein the second layer (4) has a thickness of between 10 and 30 μM. 15 11. A method of manufacturing a wallpaper (1) comprising the steps of: providing a support (2) comprising cellulose and / or polyester, having a thickness of between 100 μm and 500 μm; a first mixture on a first face (2a) of the support (2) so as to form a first layer (3), the first mixture comprising an activatable adhesive by wetting, drying the first layer (3) so as to constrain the support ( 2) in compression to prevent variations in the dimensions of the paper-paper (1) after the laying, depositing a second mixture on a second face (2b) of the support (2) opposite the first face (2a) so as to form a second layer (4), the second layer (4) being configured to allow the deposition of an inkjet printing layer, drying the second layer (4). 3034783 17 12. The method of claim 11, wherein the amount of second deposited mixture is between 10 and 30 g / m2. The method of any of claims 11 or 12, further comprising the steps of: depositing a third mixture comprising a flame retardant on the second face (2b) before depositing the second mixture, so as to form a third layer (5), dry the third layer (5). 10 14. The method of claim 13, wherein the amount of the third deposited mixture is between 10 and 30 g / m2. 15. A process according to any one of claims 11 to 14, wherein the amount of the first deposited mixture is between 25 and 50 g / m2. 16. A method according to any one of claims 11 to 15, wherein the step of depositing the first mixture is carried out at a speed less than 15 m / min. 20 17. A method according to any one of claims 11 to 16, comprising steps of removing surplus first mixture and / or second mixture and / or third mixture after deposition and before their respective dryings. 25 18. The method of claim 17, wherein the removal of surplus first mixture and / or second mixture and / or third mixture is performed by means of air slats (9c) emitting a flow of air configured to to hunt some of the surplus. 3034783 18 19. A method according to any one of claims 11 to 18, wherein the drying steps of the first and / or second and / or third layers (3, 4, 5) are carried out at a temperature between 90 and 250 ° C for a period of between 5 s and 20 s. 5