MX2012008497A - Imaging process for flooring material. - Google Patents

Abstract

A method is provided for imaging vinyl flooring material. Images are formed on vinyl flooring material having enhanced thermomechanical properties using heat activated imaging methods. Minimum shrinkage of the flooring substrate and minimum image deformation are provided by the invention.

Description

PROCEDURE FOR FORMING IMAGES FOR MATERIAL FLOORS The Applicant claims the benefit of United States Provisional Application Series No. 61/297484 filed on January 22, 2010.

TECHNICAL FIELD This invention relates to imaging in flooring materials, and more specifically is directed to imaging in synthetic floor and resin materials by a novel image transfer process.

BACKGROUND OF THE INVENTION Synthetic and / or resin materials have been used for a long time in flooring applications. Floor materials such as tiles comprising vinyls, including polyvinyl chloride, are in use. These flooring materials offer water resistance, low cost, mold resistance and mechanical stability under common home and commercial application conditions.

The mass production of vinyl flooring materials can use thermal molding of the vinyl material. The calendering of sheet tiles is carried out by the application of heat and pressure, and the heat and pressure can be used in the surface smoothing process. To accelerate manufacturing, rapid cooling methods are used at room temperature.

Rapid cooling of vinyl materials, with or without other ingredients, especially in the form of sheets, imparts a "thermal memory" to vinyl resin materials or vinyl thermoplastic materials that can change over time. Over time the material will decrease in size along the dimensions of the sheets. When the temperature of the material approaches the softening temperature, even without substantial pressure applied to the material, shrinkage becomes a problem. Therefore, when using vinyl flooring with procedures where heat is applied above room temperature, such as image transfer procedures, unwanted shrinkage results.

Thermal transfer image formation generally involves temperatures that are 176.6 ° C or more. These temperatures are substantially above the softening temperature of vinyl resins or vinyl thermoplastics. Shrinkage of more than 10% can occur, which substantially distorts the quality of the image, and reduces the physical dimensions of the flooring materials.

In order to help the thermal formation of vinyl / linoleum flooring materials, plasticizers such as phthalates and others Plasticizers are sometimes used. These plasticizers are liquids at room temperature, either in pure form or in a mixture with vinyl floor compositions, without chemical bonding. These plasticizers decrease the thermal stability, and are coloring solvents. The extra time of slow evaporation, and the migration within the floor matrix, cause the dissolution of the dyes by the plasticizers, which distorts the quality of the image.

Thermoplastic materials such as polyvinyl chloride, polyvinyl acetate and the like are often used as tiles to provide a suitable molecular linear structure for thermomechanical molding. However, there is inadequate three-dimensional stability required for a subsequent heating process, such as is used in the formation of heat transfer images. This can be true even when the temperature and / or pressure of the flooring material fluctuates, either alone or in combination. Chemicals such as household cleaning materials, organic solvents, bleaching chemicals and enzymatic substances can also alter the polymer matrix of thermoplastic materials during use.

To improve the mechanical strength and durability, a topcoat can be applied to the surface of the vinyl flooring material with inorganic filler particles, such as Al203 and S1O2. Without considering the receptive properties or permeability properties, these coatings demonstrate poor thermal cohesive properties after applying the printing process for heat transfer image formation, largely due to the differences in the coefficient of thermal expansion. The coating can also interfere with the transfer of the image.

BRIEF DESCRIPTION OF THE INVENTION A novel method of imaging for flooring materials is provided. The procedure is directed to the transfer of printed images by heat to a material for floors. Images formed on a transfer medium by inks or toner, including inks or toner comprising heat-transfer dyes, such as sublimation dyes, are transferred by heat to the vinyl flooring materials. An improved thermomechanical feature or flooring material that inhibits shrinkage from heat exposure.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows a preferred method of digital printing and image transfer according to the invention.

Figure 2 shows a sheet or tile of a flooring material that has been exposed to a heat transfer process according to the invention.

Figure 3 shows the layers of one embodiment of a flooring material that is useful with the present invention.

DETAILED DESCRIPTION OF THE INVENTION An object of the present invention is to provide a flooring material suitable for the formation of heat transfer images. The flooring material must be able to withstand a heating process during image formation without physical thermal shrinkage of the material or distortion of the image.

In one embodiment of the invention, the flooring material comprises at least two layers. A first layer may comprise a transparent or light colored upper receptive layer of a heat transfer image comprising vinyl materials, and a second, lower layer, or sublayer, which acts as a thermal shrinkage control layer that is firmly attached to the top layer.

An exemplary imaging method according to the invention uses vinyl flooring material as a finally exposed substrate. The vinyl floor is a material for floors that comprises a vinyl group. In one embodiment, the liquid ink comprising sublimable dyes is printed digitally on an intermediate transfer sheet, which may be paper. The dyes are subsequently heated to their heat activation temperature (s), whereby the dyes are activated and transferred to the vinyl flooring material. In the case of dyes or sublimation dyes, the activation by heat causes sublimation dyes to sublimate and join the material for vinyl flooring, with which the sublimable dyes have an affinity. The heat activation of dyes comprising sublimation dyes typically occurs between 160 ° C and 210 ° C, or approximately 325 ° F and 410 ° F.

In other embodiments, the image formed on the floor substrate can be created by printing directly or by applying inks or toners comprising thermally diffusible dyes, including pigmented dyes, disperse dyes and sublimation dyes. The image is fixed to the substrate by a subsequent fixing method, which may be a thermal and / or radiation process. The temperatures used for the thermal fixation process are generally between 160 ° C and 210 ° C, or approximately 325 ° F and 410 ° F.

In order to decrease the thermal shrinkage and improve the thermal stability of the image of the vinyl flooring material, in one embodiment of the present invention, a molten vinyl material is used. The flooring material of this embodiment may comprise vinyl articles in sheet form (polyvinyl chloride or polyvinylidene chloride). The molten vinyl floor can be formed directly with the required thickness where the molecules in the polymer matrix are in a thermal equilibrium stage at the forming temperature (above ambient temperature) without allowing the vinyl ingredients to carry a "thermal memory" during the film forming procedure. Therefore, they are more stable. In addition, sheet vinyl flooring materials have better fit and light resistance properties. In contrast, calendered vinyl is formed by pulling the vinyl material through thermomechanical forces along the dimensions of the sheets. The thickness of the receiving layer of the vinyl polymer may be in the range of 15 to 250 microns.

A thermal maturing process or thermal conditioning may be used according to the present invention. This thermal maturation procedure allows the vinyl composition, with or without the sublayer, to be subjected to a temperature close to the heat transfer image formation temperature, but before the heat transfer imaging process. , so that thermal equilibrium along the polymer matrix can be achieved. This is especially useful if a non-cast vinyl floor tile or sheet is to be used. In addition, such a thermal maturation or conditioning process helps to remove unwanted plasticizers or plasticizer residues in the matrix of the receptive vinyl polymer.

The temperature of thermal maturation should be close to the temperature for heat transfer imaging. Temperatures that are materially lower, such as a difference of 3.8 ° C, are not likely to be effective in achieving thermal equilibrium. The ripening process can be carried out during the manufacture of vinyl floor sheets, after the formation step of the sheet, but before joining the sub-layer. Maturation can also be carried out prior to the heat transfer imaging process. Depending on the specific vinyl material, a thermal maturation temperature between 163 ° C and 204.4 ° C can be used, and for many materials, the preferred temperature is between 163 ° C and 190.5 ° C, and a period of maturation between 30 seconds and 300 seconds.

In another embodiment, no plasticiser or superplasticizer material is used in the formation of the vinyl receptive layer, or minimal use is made of these materials. Plasticizers are additives that help the plasticity and / or flexibility of vinyl materials during sheet formation, but can be detrimental to humans and the environment. These materials are also detrimental to the stability of the image. The most used plasticisers for the formation of vinyl sheets are the phthalates or phthalate esters, including di-2-ethyl hexyl phthalate (DEHP), diisodecyl phthalate (DIDP), diisononyl phthalate (DINP), dindecyl phthalate (DUP), and benzylbutylphthalate (BBP). Flaxseed oil, pine oil or the like that are not completely polymerized, while trapped within the linoleum products, can also act as plasticizers, and can be detrimental to the stability of the image. Therefore, it is preferable to avoid its use. Preferably, less than 1% of the total plasticizers of the syt-phthalate type is to be used for the present invention, and most preferably no plasticizer is going to Use in the formation of the receptive layer of vinyl. Examples of syphtalate plasticizers include but are not limited to Hexamoll® DINCH by BASF, Colorite® series by Colorite Polymers, and Eastman ™ DBT by Eastman Chemicals.

In order to maintain excellent compliance and flexibility with little or no external plasticizer, it is preferred to use polyvinyl chloride (PVC) with an average molecular weight (Mn) of from 1,000 to 100,000, and more preferably from 2,000 to 10,000.

Optionally, thermosetting polymeric materials with high sublimation printing receptivity can be used as part of the vinyl receptive composition. These polymers not only improve the receptivity of heat transfer imaging to improve the color intensity of the final images, but also prevent migration of the thermal dye into the interior of the vinyl polymer matrix. This is contrasted with thermoplastic materials that lack "blocking" properties of sublimation dye properties after printing. On a microscopic scale, these polymers provide improved stability of three-dimensional structures and provide permanence of sublimation dyes within the vinyl thermoplastic matrix. Thermosetting synthetic polymers such as polyester such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), polyurethane (PU), polyester glycol such as polyethylene glycol terephthalate (PETG), polyamide (PA) and polyimide (Pl) ), either as Homopolymer, copolymer, terpolymer or the like can be used as co-molding, co-extrusion, co-calendering ingredients, or as fillers / addis, during the vinyl flooring process. Preferably, the thermoset polymer ranges from 1% to 50% by weight.

Dyes including dyes and pigments, and addis such as thermal or radiation stabilizing agents, polymerization catalysts, blowing agents, radiation blocking agents, optical brighteners, light reflecting ingredients, etc., can be used in the recep layer of vinyl to achieve the desired thermal, mechanical, acoustic, visual appearance, chemical resistance properties or radiation stability of the article for floors. Nega thermal expansion materials (NTE) can also be used as addis in the composition of the vinyl polymer. 208). An example of such materials is zirconium tungstate (ZrVN ^ Oe).

In one embodiment of the present invention a sub-layer or support is used for the vinyl floor material. The sublayer of the present invention comprises thermal stabilizing materials such as glass fiber, flax or jute, bamboo, metal, engineering polymer synthetic fabric or a fiber structure incorporated along the lamella axes (xy plane) . The sub-layer is preferred to meet the requirements of ASTM F1303 (Standard Specification for Vinyl Sheet Coating with Support). The material of the synthetic fabric or fiber has a relaly smaller coefficient of thermal expansion. For example, the coefficient linear thermal expansion of polyvinyl chloride (PVC) is 5.2 x 10"5 / C at 20 ° C, while that of the synthetic stainless steel fabric is 1.7 x 10" 5 / C at 20 ° C, and that of Common wood material such as bamboo is 0.65 x 10"5 / C at 20 ° C. The built-in fibers or synthetic fabrics with fiber materials of low thermal expansion coefficient with a resin, plastic or rubber composition stabilize the dimensional structure during the heat transfer printing In the present invention, fibers with a linear coefficient of thermal expansion (at 20 ° C) lower than 2.0 x 10"5 / C are preferred for use.

Natural or synthetic polymers such as latex rubber, melamine or urea formaldehyde (for example hexametoxymethylmelamine, hydroxymethyl dimethoxymethyl melamine, urea dimethylol,?,? - dimethylol ethylene urea), reac and non-reac polymeric silane, styrene-acrylonitrile (SAN), epoxy , polyester, polyurethane, synthetic rubber, such as butadiene, styrene butadiene, halobutyl rubber, neoprene or chloroprene, vinyl such as polyvinyl chloride, etc., can be used as the main ingredients, either alone or in a mixture, and in combination with the materials of low thermal expansion fiber. The resulting sublayer can be thermally or chemically bound to the recep layer of vinyl. To avoid thermal expansion or uneven shrinkage during the imaging or transfer process, the difference in the coefficient of thermal expansion between the resulting sublayer and the recep layer of vinyl should preferably not exceed 5%. A large difference in thermal expansion between the layers can result in unwanted bending or curling, or even separation of the layers, after the heat transfer imaging process. The thickness of the sublayer may be in the range of 50 to 500 microns.

In order to avoid unnecessary migration of the dye or diffusion into the sub-layer, an optional blocking layer can be applied or formed between the sub-layer and the recep recep vinyl layer. The blocking layer inhibits the penetration or migration of dye from the recep layer of the image, especially during long-term use. Therefore, the image sharpness and optical intensity can be maintained throughout the use of the flooring material. Highly crosslinked polymer / resin materials with little or no affinity and / or with little or no tendency to permeate dyes are preferred to form the blocking layer. Examples of such materials include high density polyethylene or polypropylene, metallized polyethylene or polypropylene, polyether acrylate, epoxide polymer, polysiloxanes, cellulose or modified cellulose polymer, or organometallic polymeric materials.

In one embodiment, the fibrous material is oriented so that synthetic fibers or fabrics are placed along the plane of the laminae of the sublayer bi-axially (plane xy instead of z axis), so that the expansion or total thermal shrinkages are controlled optimally. Preferably, not less than 1% by weight of the low coefficient of expansion fibers are used in the sublayer and more preferably not less than 5% by weight is used.

Optionally a clear or transparent pass-through polymer layer 6 is applied to the surface of the vinyl receptive layer 8, which is applied over the sub-layer 10 or support. Figure 3. The clear or transparent layer can be produced either by lamination or coating. The term "pass through" as used herein means that the sublimation or heat activatable dye printed on the transfer medium will be sublimated or diffused through the polymeric layer and will be condensed and deposited in the receptive layer of the polymeric layer. vinyl during the heat transfer step. However, said layer will not allow the diffusion of cold sublimation material of the image after the transfer procedure has been completed. As such, the additional protection of mechanical, chemical radiation can be provided through the coverage of the polymer layer passing through.

The clear or transparent pass through coating further comprises at least one clear polymeric or resinous material (s) with little or no affinity to the condensed or gasified dye sublimation, and allows the passage through sublimation of the image from the outside from the layer to the receptive vinyl during the transfer printing process. The image then attaches permanently to the receptive vinyl layer, and below the pass-through layer. Thermoset or thermoplastic polymeric materials capable of forming a layer of Passage through or membrane that can be natural or synthetic, can be used as coating ingredients. In order to achieve light resistance and mechanical stability, thermoset polymeric materials with various additives can be used or formed by a crosslinking reaction to create a firm bond, and a non-sticky pass through layer that eliminates peeling problems during the heat transfer process, as taught in U.S. Patent Application Serial No. 61/260 442 and PCT / US10 / 56365.

Oxygen and ozone in the air can penetrate through the pass-through layer and create a decrease in light resistance of the printed image. The additives in the polymer layer with properties of blocking or sequestering of oxygen (antioxidant) can be used. Examples of non-polymeric oxygen scavenger chemicals include ascorbic acid, ascorbate, carbohydrazide, erythorbate, methyl ethyl ketoxime, hydroquinone, and diethylhydroxylamine, unsaturated fatty acid, 2,6-di (t-butyl) -4-methylphenol (BHT), 2,2'-methylene-bis (6-t-butyl-p-cresol), and triphenylphosphite. Kidnappers and / or polymeric oxygen antioxidants (Oxygen Hijacker Polymers - OSP) such as polypropylene, polybutadiene, polyisoprene, ethylene-cyclohexenylmethyl acrylate copolymer (ECHA), and ethylene-methyl-acrylate-cyclohexenylmethyl acrylate terpolymer (EMCM) can also be used in the cross-pass polymer layer.

Example of the Composition of the Clear Layer of Crossing Polymer Hexametoxymethyl Melamine 0-45% Resin Co-reactive 0-50% Catalyst 0-3% Release agent 0-10% Kidnapper / Oxygen Antioxidant 0-5% Abrasion Resistant Additives 0-5% Other Coating Additives 0-15% Vehicle balance The dry coating weight of the clear or transparent pass-through layer generally ranges from 0.5-25 g / m2, and is preferred to be 1-3 g / m2.

An image is printed on an intermediate base sheet 12. The image can be printed with a digital printer, such as an ink jet printer driven by a computer 24. After the image is printed on the medium, the image is ready for transfer from the middle to vinyl flooring material.

The use of computer technology allows the substantially instantaneous printing of images. For example, video cameras or scanners 30 can be used to capture a color image on a computer 20. Images created or stored on a computer can be printed at will, regardless of the size to be executed. The image from the computer can be printed or transferred onto the vinyl flooring material by any other suitable means of printing, including those that are capable of printing in multiple colors, including mechanical thermal printers, inkjet printers and electrophotographic printers or electrostatic, and transferred as described above.

Computers and digital printers are inexpensive, and the transfer of photographs and computer generated images can be made to substrates 16. These transfers can be produced by end users in the home, as well as in commercial establishments. The image is transferred by the heat application as described above. A clothes iron, or a heat press 26 intended to achieve such transfers are examples of devices that can be used for heat transfer.

Claims (16)

NOVELTY OF THE INVENTION CLAIMS

1. - An imaging method in a flooring material, comprising the steps of: applying heat to a printed image comprising a heat-activatable dye, wherein the heat activates the heat-activatable dye, and an image receptive layer of the flooring material has an affinity with the colorant when the heat activatable dye is activated by heat, and the heat activatable dye is attached to the flooring material to form an image; wherein the flooring material comprises the image receptive layer and a shrinkage control layer, and wherein the image receptive layer dimensionally shrinks no more than 5% (five percent) relative to the shrinkage control layer as Result of the application of heat to said flooring material during the formation of images in the flooring material.

2. The method of forming images in a flooring material according to claim 1, further characterized in that the image receptive layer of the flooring material comprises a vinyl group.

3. The method of forming images in a flooring material according to any of the claims precedents, further characterized by additionally comprising the step of thermal maturation of the image receptive layer by applying heat to the image receptive layer prior to imaging in the flooring material.

4. The method of forming images in a flooring material according to any of the preceding claims, further characterized in that it additionally comprises the step of thermal maturation of the image receptive layer by applying heat to the image receptive layer at a a temperature that is not substantially lower than a temperature of the activating heat of the heat-activatable dye, and before the imaging of the flooring material.

5. The method of forming images in a flooring material according to any of the preceding claims, further characterized in that said flooring material comprises molten vinyl.

6. The method of forming images in a flooring material according to any of the preceding claims, further characterized in that the shrinkage control layer comprises a fibrous material.

7. - The method of forming images in a material for floors according to any of the preceding claims, further characterized in that the control layer of Shrinkage has a linear coefficient of thermal expansion (at 20 ° C) of less than 2.0 x 10"5 / ° C.

8. The method of forming images in a flooring material according to any of the preceding claims, further characterized in that the image receptive layer of the flooring material comprises a thermosetting polymer.

9. The method of imaging in a flooring material according to any of the preceding claims, further characterized in that the image receptive layer of the flooring material comprises a vinyl group, and wherein the heat activated dye has an affinity for the vinyl group and joins the vinyl group to form the image.

10. The method of imaging in a flooring material according to any of the preceding claims, further characterized in that the heat activatable dye comprises sublimation dye, and the image receptive layer of the flooring material comprises a vinyl group, and , where the sublimation dye sublimates before the heat application and the sublimated sublimation dye has an affinity for the vinyl group and joins the vinyl group to form the image.

1. The method of forming images in a flooring material according to any of the preceding claims, further characterized in that the flooring material comprises additionally a pass-through layer, wherein the pass-through layer has little or no affinity with the heat-activatable dye, and wherein the heat-activatable dye passes through the pass-through layer upon heat activation and does not substantially bond with the passage through the pass-through layer, and wherein the heat activatable dye passes through the pass-through layer and binds to the image receptive layer.

12. - The method of forming images in a flooring material according to any of the preceding claims, further characterized in that the flooring material additionally comprises a blocking layer located between the image receptive layer and the shrinkage control layer, wherein the blocking layer inhibits the passage of the image through the image receptive layer to the shrinkage control layer after image formation of the flooring material.

13. - The method of forming images in a flooring material according to any of the preceding claims, further characterized in that the flooring material additionally comprises a transparent layer of passage through, wherein the pass-through layer comprises a resinous material and the pass-through layer has little or no affinity with the heat-activatable dye, and wherein the heat-activatable dye passes through the pass-through layer upon heat activation and does not substantially bind to the heat-sensitive layer. passage through and wherein the heat-activatable dye passes through the pass-through layer and attaches to the image receptive layer.

14. - The method of forming images in a flooring material according to any of the preceding claims, further characterized in that the flooring material additionally comprises a transparent layer of passage through, wherein the pass-through layer has little or no affinity with the heat-activatable dye, and wherein the heat-activatable dye passes through the pass-through layer upon heat activation and does not substantially bind to the pass-through layer, and wherein the dye activatable by Heat passes through the pass-through layer and attaches to the receptive image layer.

15. The process of imaging in a flooring material according to any of the preceding claims, further characterized in that the image receptive layer of the flooring material comprises polyurethane, and wherein the heat activatable dye has an affinity with the polyurethane. , and the heat activated dye joins the polyurethane to form the image.

16. The method of forming images in a flooring material according to any of the preceding claims, further characterized in that the image receptive layer of the flooring material comprises polyester, and wherein the heat activatable dye has an affinity with the polyester , and the heat-activatable dye is attached to the polyester to form the image.