Transfer paper for sublimation printing comprising a cationic agent

Abstract

The present invention relates to a transfer paper for sublimation printing comprising a fibrous substrate, said transfer paper having on at least one of its faces one or more cationic agents deposited on the fibrous substrate by means of a surface treatment, the amount of one or more cationic agents being greater than or equal to 8% by dry weight of the total dry weight of one or more compounds added to the fibrous substrate by means of a surface treatment.

Description

[0001] This invention relates to transfer paper for sublimation printing, and more particularly to, but not limited to, transfer paper that can be printed by inkjet printing.

[0002] Sublimation printing uses sublimable inks to provide images on substrates such as metal, glass, plastic, or fabric surfaces. When printing with sublimable inks, the inks can be printed directly onto the final substrate or they can be printed indirectly. In the case of indirect printing, the ink is first printed onto paper, called transfer paper, and then the image printed on the transfer paper is transferred to the final substrate using a transfer press. Application US 2008 / 0229962 describes this printing process.

[0003] Applications EP 2965919 A1, WO00 / 06392, WO2008 / 006434 and WO2016 / 074671 disclose transfer paper for sublimation printing.

[0004] More specifically, application EP2965919 A1 discloses a transfer paper comprising a reservoir having an outer surface configured to receive sublimable ink, and a shielding layer applied to an inner surface of the reservoir and configured to form a barrier for the transport of the sublimable ink. The reservoir may further comprise a small portion of a cationic polymer to fix the dye in the sublimable ink to the surface of the transfer paper.

[0005] Application WO00 / 06392 describes a transfer paper including a shielding layer, having a porosity of up to 100 ml / min.

[0006] Application WO2008 / 006434 discloses paper having a layer comprising a semi-synthetic polymer with thermoplastic properties.

[0007] Application WO2016 / 074671 describes paper having layers including thermoplastic particles.

[0008] Sublimation transfer paper printed by inkjet printing typically includes a barrier layer based on a hydrophilic polymer (such as carboxymethyl cellulose, starch, or polyvinyl alcohol), and is more or less loaded with low specific surface area pigments, such as kaolin or calcium carbonate, or high specific surface area pigments, such as silica.

[0009] The presence of a barrier layer based on hydrophilic polymers results in long drying times, limiting printing rates and causing color mixing and feathering, which impairs print quality.

[0010] Loading can mitigate the aforementioned drawbacks, but it can lead to additional formulation costs and / or limit the sublimation transfer rate.

[0011] Therefore, there is an unmet need for a method to obtain a transfer paper for sublimation printing that can be inkjet printed, has good printability and limited drying time, high transfer rate and relatively low weight, especially less than or equal to 50 g / m². 2 .

[0012] The present invention addresses and achieves this need by using a sublimation printing transfer paper comprising a fiber substrate, the transfer paper having one or more cationic agents deposited on the fiber substrate by means of a surface treatment on at least one side, the amount of the one or more cationic agents being greater than or equal to 8% by dry weight of the total dry weight of one or more compounds provided to the fiber substrate by the surface treatment, for example greater than or equal to 9% or even 10%.

[0013] The present invention also relates to transfer paper for sublimation printing, which has a content of at least 0.2 g / m² on at least one side. 2 One or more cationic agents, wherein the transfer paper does not contain pigments, binders, and other formulation ingredients such as dispersants, wetting agents, thickeners, insoluble agents, sizing agents, gloss agents, or dyes on this side, or the transfer paper contains one or more pigments and / or binders and / or other formulation ingredients such as dispersants, wetting agents, thickeners, insoluble agents, sizing agents, gloss agents, or dyes on this side, in g / m 2 The total amount of the single or preferred cationic agent is less than or equal to 13 times the amount of one or more cationic agents, for example less than or equal to 12 times, or even 10 times, 8 times or 5 times.

[0014] Cationic agents are typically used in small amounts as ink fixatives (fixing agents) in inkjet printing to hold the ink on the surface and prevent it from seeping out in water. The cationic agents present in a higher proportion in this invention unexpectedly ensure good transfer via sublimation, with surprisingly little ink remaining on the transfer paper during sublimation.

[0015] The transfer paper according to the invention has good printability, especially due to the ink being fixed to the surface by one or more cationic agents.

[0016] Fixing ink pigments to the surface of a fiber substrate using one or more cationic agents improves the optical density after transfer and limits feathering. This improves the binding.

[0017] The absence or lack of pigments, binders, and any other formulation agents, such as those listed above, can optimize the compromise of ink setting / drying speed.

[0018] Surface treatment can be a single layer or multiple layers.

[0019] The amount of one or more cationic agents is advantageously greater than or equal to 8%, or even 9% or 10% of the total dry weight of one or more compounds provided by one or more layers applied by surface treatment as described above, on a dry weight basis.

[0020] The transfer paper may be free of mineral loading, also known as pigment, on at least one side containing one or more cationic agents, or may have one or more mineral loadings on that side, in an amount less than or equal to 10 g / m². 2 .

[0021] One or more mineral loads may be selected from calcium carbonate, calcined kaolin, talc, TiO2, hydroxides, especially aluminum (Al(OH)3) or magnesium hydroxides, sulfates, especially BaSO4 or CaSO4, natural or synthetic aluminum silicate, alumina, and mixtures thereof. Mineral loads help retain the ink on the surface. The presence of one or more cationic agents as described in this invention makes the presence of mineral loads unnecessary, or at least limits their amount.

[0022] The transfer paper may be free of adhesive on at least one side containing one or more cationic agents, or it may have one or more adhesives on that side, in an amount less than or equal to 8 g / m². 2 .

[0023] One or more binders are preferably selected from water-soluble binders, such as polyvinyl alcohol, starch, gelatin, soy or casein, and mixtures thereof.

[0024] One or more cationic agents may be present only on one side of the transfer paper intended to be printed.

[0025] One or more cationic agents may be organic cationic agents.

[0026] One or more cationic agents may be selected from epichlorohydrin polyamines, particularly polyephichlorohydrin dimethylamine, polyethyleneimine, and organic quaternary ammonium salts. Preferred organic cationic agents among organic quaternary ammonium salts are, in particular, polydiallyl dimethylammonium chloride, also known as PolyDADMAC. One or more cationic agents may be present at a concentration greater than or equal to 0.2 g / m³. 2 Especially those greater than or equal to 0.6 g / m 2 The amount of [something] exists on the surface.

[0027] The surface may also include one or more alkaline earth metal salts, particularly selected from calcium salts, preferably calcium chloride or calcium nitrate, and magnesium salts, particularly magnesium sulfate or magnesium chloride, which may also help improve the transfer.

[0028] The fiber substrate prior to treatment may be free of cationic agents and / or mineral loadings and / or binders and / or formulation agents, such as dispersants, wetting agents, thickeners, insolubilizing agents, sizing agents, brighteners, or dyes. The fiber substrate may include natural and / or synthetic fibers, particularly long and / or short cellulose fibers.

[0029] Transfer paper is preferably printed using inkjet printing. It can also be printed using a rotary press.

[0030] The transfer paper preferably has a Bendtsen air permeability of 100 ml / min or more, particularly 200 ml / min or more (according to standard ISO 5636-3).

[0031] This air permeability gives the paper an open structure. This ensures that the ink applied to the transfer paper dries quickly. Therefore, the increased ink drying speed results in higher yield compared to lower air permeability.

[0032] Transfer paper can have weights of 25 and 150 g / m². 2 Between (including the extreme values), particularly at 30 and 75 g / m 2 The value (including the endpoints) is preferably less than or equal to 50 g / m 2 .

[0033] Transfer paper is typically used only once.

[0034] In one embodiment, the amount of one or more cationic agents present on the surface is greater than or equal to 0.2 g / m². 2 The transfer paper does not contain pigments, binders, and formulation agents such as dispersants, wetting agents, thickeners, insoluble agents, sizing agents, gloss agents, or dyes on the stated side, or the transfer paper contains one or more pigments and / or binders and / or formulation agents such as those described above, in g / m 2 The total amount, individually or preferably, is less than or equal to 13 times the amount of one or more cationic agents, and particularly less than or equal to 12 times, 10 times, 8 times or 5 times.

[0035] The present invention also relates to a method for manufacturing transfer paper for sublimation printing, specifically as described above, wherein the surface treatment involves depositing one or more cationic agents on at least one side of a fiber substrate, the amount of the one or more cationic agents being greater than or equal to 8% by dry weight of the total dry weight of one or more compounds provided by the surface treatment on the fiber substrate, particularly greater than or equal to 9% or 10%.

[0036] The present invention also relates to a method for manufacturing transfer paper for sublimation printing, particularly as described above, wherein a surface treatment involves depositing one or more cationic agents on at least one side of a fiber substrate, and the treated side of the transfer paper comprises an amount greater than or equal to 0.2 g / m². 2 The transfer paper contains one or more cationic agents in a quantity that does not contain pigments, binders, and formulation agents such as dispersants, wetting agents, thickeners, insoluble agents, sizing agents, gloss agents, or dyes on that side, or the transfer paper contains one or more pigments and / or binders and / or formulation agents such as those described above, in g / m 2 The total amount, individually or preferably, is less than or equal to 13 times the amount of the cationic agent, and particularly less than or equal to 12 times, 10 times, 8 times or 5 times.

[0037] Surface treatment can be a single layer or multiple layers.

[0038] The method according to the present invention may include manufacturing a fiber substrate.

[0039] Surface treatments can be applied online or offline.

[0040] One or more cationic agents can be deposited on one side of the fiber substrate.

[0041] A composition comprising one or more cationic agents can be deposited on the surface of a fiber substrate by surface treatment, and the amount of composition deposited on the surface of the fiber substrate can be between 0.2 and 15 g / m² on a dry weight basis. 2 Between (including the extreme values), preferably between 0.5 and 8 g / m 2 between.

[0042] Surface treatments can be applied using sizing presses, film transfer presses, or coating systems, particularly curtain, doctor blade, air knife, crayon, or even engraved roller coating systems.

[0043] The present invention also relates to printed transfer paper for sublimation printing, including transfer paper as defined above and at least one print on one side of the transfer paper containing one or more cationic agents, particularly inkjet printing with at least one sublimable ink.

[0044] The present invention also relates to a printing method for transfer paper for sublimation printing, wherein the side of the transfer paper, as described above, comprising one or more cationic agents is printed with at least one ink, particularly by inkjet printing.

[0045] As a variation, printing can be performed using a rotary press.

[0046] For example, printing can be done in four colors using ink cartridges containing primary color inks: black, magenta, yellow, and cyan, as well as possible synthetic colors (mixed colors). The inks are specifically formulated from water-based sublimable pigments.

[0047] The present invention also relates to a method for decorating a substrate, wherein a print is transferred from the transfer paper printed as described above to the substrate by sublimation.

[0048] The substrate can be a metal, glass, plastic or fabric surface, particularly a polyester fabric, preferably a fabric mainly containing polyester. Example

[0049] The compositions described in the table below are deposited on one side of a fibrous substrate using a Mayer rod, and their composition and properties are described below. The fibrous substrate treated with the compositions forms a transfer paper.

[0050] Base paper before coating

[0051] Fiber composition: 30% cork + 70% mixed short fibers

[0052] Basis weight = 60g / m 2

[0053] Cobb size 60s = 15g / m 2

[0054] Bentson porosity = 1500 ml / min

[0055] Coating rules: Based on the composition and deposition in the table below.

[0056] Printing tests were conducted on paper using a SAWGRASS SG400 printing press, and transfer printing was performed on polyester fabric by pressing at 200°C for one minute.

[0057] Black ink (SAWGRASS Sublijet Black) is deposited on the surface of a fiber substrate treated with the composition. This results in a black wash. The transfer paper treated with the ink forms the printed transfer paper.

[0058] The optical density after transfer to polyester fabric was measured using an X-rite 500 spectrometer.

[0059] The number of parts is expressed as dry weight.

[0060]

[0061] In Example 3, "20+80" means using 20 parts of ground CaCO3 and 80 parts of PCC (precipitated calcium carbonate).

[0062] The Bentsen air permeability of Examples 2 to 5 is greater than 100 ml / min.

[0063] It is worth noting that the transfer paper printed according to the present invention in Examples 2, 3, 4 and 5 has a greater optical density than the transfer paper printed according to Comparative Example 1 that is not based on the present invention.

Claims

1. A sublimation printing transfer paper comprising a fiber substrate, said transfer paper having on at least one side one or more cationic agents deposited on said fiber substrate by means of a surface treatment, said one or more cationic agents at a concentration of at least 0.2 g / m 2 The amount of the transfer paper present on the surface is free of pigments, binders and any other formulation agents, the formulation agents including dispersants, wetting agents, thickeners, insoluble agents, sizing agents, gloss agents and dyes, and the one or more cationic agents are organic cationic agents.

2. The transfer paper according to claim 1, wherein the one or more cationic agents are selected from epichlorohydrin polyamines, polyethyleneimine, and organic quaternary ammonium salts.

3. The transfer paper according to claim 2, wherein the epichlorohydrin polyamine is polyepoxychlorohydrin dimethylamine.

4. The transfer paper according to claim 2, wherein the organic quaternary ammonium salt is polydiallyldimethylammonium chloride.

5. The transfer paper according to claim 1, wherein the one or more cationic agents are at a concentration greater than or equal to 0.6 g / m². 2 The quantity exists on the surface.

6. The transfer paper according to claim 1, wherein the transfer paper has a Bentsen air permeability greater than or equal to 100 ml / min.

7. The transfer paper according to claim 1, wherein the transfer paper has a weight of 25 to 150 g / m³. 2 between.

8. The method for manufacturing transfer paper according to any one of claims 1 to 7, wherein, The surface treatment involves depositing one or more cationic agents on at least one side of a fibrous substrate, wherein the treated side of the transfer paper contains an amount greater than or equal to 0.2 g / m². 2 The transfer paper contains one or more cationic agents in an amount that do not contain pigments, binders, or any other formulation agents on the surface, and the formulation agents include dispersants, wetting agents, thickeners, insoluble agents, sizing agents, gloss agents, and dyes.

9. The manufacturing method according to claim 8, wherein, The fiber substrate is manufactured and a surface treatment is applied online or offline.

10. The manufacturing method according to claim 8, wherein the amount of the one or more cationic agents deposited on the surface of the fiber substrate is between 0.2 and 15 g / m² on a dry weight basis. 2 between.

11. The manufacturing method according to claim 8, wherein the surface treatment is applied using a sizing press, a film transfer press, a doctor blade coater, an air knife coater, a bar coater, a curtain coater, or by means of a carving roller.

12. Printed sublimation printing transfer paper, comprising the transfer paper according to any one of claims 1 to 7, and at least one print on the surface of the transfer paper containing one or more cationic agents.

13. A printing method for transfer paper used in sublimation printing, wherein, The surface of the transfer paper comprising one or more cationic agents according to any one of claims 1 to 7 is printed with at least one ink.

14. Methods for decorating printing substrates, among which, The print made on transfer paper by the printing method according to claim 13 is transferred to the substrate by sublimation.

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