JP5363197B2 - Ceramic image forming system and ceramic image forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve problems of a conventional technique in printing image to a ceramic product, wherein the density of the image is low, the image is not clear, deformation of the image or unintended coloring is produced in printing to the ceramic product, and reproducibility of an original image is low. <P>SOLUTION: A ceramic image forming system uses: a toner containing a resin, an inorganic pigment, and an external additive at a ratio of 100:40-110:0.5-1.0; a transfer sheet formed by sequentially layering an adhesive layer and a resin layer at a content ratio of 5:7-10 on a mounting layer; and a cover sheet with a layer containing at least a glaze is formed on a base material layer. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a ceramic image forming system and a ceramic image forming method for forming an arbitrary image on a ceramic product or the like in a simple and highly reproducible state.

  The following publicly known documents include, for example, a “transfer sheet” which mainly comprises a mount layer and an adhesive layer by using a “printing apparatus” including a so-called electrophotographic copying apparatus for an arbitrary developed photograph (hereinafter referred to as an image). A technique in which an image layer is formed thereon, a mount layer is separated from the transfer sheet, the image layer is transferred to a ceramic product such as ceramics, and the ceramic product and the image layer are baked (hereinafter referred to as a ceramic product image forming system). ) Is disclosed.

  As a technique for protecting the image layer at the time of printing an image on a ceramic product, there are mainly the following methods. A silk screen method in which a coating solvent is applied to the surface of the image layer from a silk mesh with a spatula. A laminating method in which a coating sheet containing a coating solvent is placed on a transfer sheet and transferred onto an image layer on the transfer sheet by a laminator. A spray method in which an image is transferred from a transfer sheet to a ceramic product, and then a coating solvent is sprayed onto the ceramic product.

Japanese Patent No. 3482453 Japanese Patent No. 3259026 Japanese Patent No. 3520890 JP-A-10-129198 Japanese Patent No. 3897217 Japanese Patent No. 3871099 Ikoku Patent Application No. 2005TO0769 Ikoku Patent Application No. 2006TO0123 Ikoku Patent Application No. 2007BI0013

  Patent Documents 1 and 2 describe that “toner” contains a flux for fixing a coloring matter (pigment) component in the toner to the ceramic surface.

  Patent Document 3 describes that “toner” contains an upper drug (hereinafter referred to as glaze) made of glass components in the kiln industry.

  Patent Documents 4, 7 and 8 describe that in the “transfer sheet”, the transfer sheet contains glaze.

  Patent Document 5 describes that in a “transfer sheet”, a layer containing a resin component together with a plasticizer is formed on the surface side of the paste layer of the transfer sheet (the surface opposite to the mount layer).

  Patent Document 6 describes that in a “transfer sheet”, a layer containing a resin component and a layer containing a toner component containing a glaze are sequentially formed on the surface side of the adhesive layer.

  Patent Document 9 describes spraying a flux on the transfer sheet by a spray method with respect to the “coating layer”.

However, the techniques of Patent Documents 1 to 8 have the following problems, respectively.
In other words, Patent Documents 1 to 3 are technologies relating to “toner”, but since the toner contains a flux or glaze, the ratio of the pigment component is reduced in the first place, and the density of the image is low (light). In addition, there is a problem that the image is not clear and the toner itself is expensive.

  In particular, if glaze is contained in the toner, the glaze component will destabilize the chargeability of the toner, so the white portion of the printed transfer sheet will be unnecessarily colored, or the dark portion of the printed image will be decolorized white. May occur (hereinafter referred to as white spots).

  Patent Documents 4 to 8 are technologies related to “transfer sheets”. Patent Documents 4, 7, and 8 have a configuration in which an image layer is formed on a glaze layer. Therefore, when baking is performed on a ceramic product, the toner component of the image layer also flows due to the flow of the glaze layer, so that the bleeding occurs. As a result, the image may be corrupted (not intended).

  Since Patent Document 5 has a configuration containing a plasticizer, the highly chargeable plasticizer is unnecessarily charged during image formation in the printing apparatus and moves toner onto the transfer sheet. There is a problem that unintentional coloring occurs in white portions.

  In Patent Document 6, as a result, a glaze layer is formed in the same layer or lower layer as the pigment component of the toner in the transfer sheet. Therefore, as in Patent Document 4, when the ceramic product is baked after transfer, the glaze layer is formed. The toner component of the image layer may also flow due to the flow of the image, and the image may be destroyed (not intended) as if it is blurred.

  Patent Document 9 relates to a method for forming a coating layer. First, in the spray method of Patent Document 9, the coating solvent may be non-uniform. Image defects such as burning without being protected and whitening occur. Furthermore, the spray method requires a drying time, is troublesome, and has a risk of inhalation into the human body.

  In addition, the silk screen method requires a drying time and may cause individual differences and unevenness in application. In addition, in the silk screen method, the coating solvent is applied thickly in some cases, the rigidity of the image layer becomes high (hard), and when the image layer is transferred to the ceramic product on the curved surface, the image layer is combined with the coating layer. There is a possibility of cracking.

  The problems to be solved are that, in the well-known techniques and Patent Documents 1 to 9, the “toner” has a low image density and is not clear, and the “transfer sheet” is transferred to a ceramic product after being baked. There is a possibility that the image may be lost and unintentional coloring may occur. Regarding the “coating layer”, it may take time and time, such as requiring a drying time, may cause individual differences, and the image layer may be cracked. This is to eliminate the point that an arbitrary image cannot be formed on a ceramic product in a simple and highly reproducible state.

  The ceramic image forming system of the present invention comprises a resin, an inorganic pigment, and an external additive in a ratio of 100: 40 to 110: 0.5 to 1.0. Is a transfer sheet laminated at a content ratio of 5: 7 to 10 and a cover sheet in which a layer containing at least a glaze is formed on the base material layer.

  In the present invention, since the toner and transfer sheet do not contain a flux or glaze, and the cover sheet contains glaze, the density of the image resulting from the inclusion of glaze or flux in the toner is low and not clear. In addition, in the transfer sheet, the collapse of the image at the time of printing due to the presence of the glaze in the lower layer or the same layer of the image layer is improved, and further, the cover sheet integrated with the transfer sheet by a laminator is used. Thus, there is an advantage that an individual difference such as coating or spraying is improved, and thus it is possible to form an arbitrary image on a ceramic product in a simple and highly reproducible state.

  The toner contains a resin, an inorganic pigment, and an external additive as main components. That is, it does not contain a flux or glaze as in Patent Documents 1 to 3. The toner contains a resin, an inorganic pigment, and an external additive in a ratio of 100: 40 to 110: 0.5 to 1.0. The reason for this is that if the amount of inorganic pigment is less than 40, the image density is low and all the colored portions are thinned. If the amount of inorganic pigment is more than 110, the chargeability of the toner is disturbed and the unintended portion of the transfer sheet is colored. End up. If the external additive is less than 0.5, the fluidity of the toner is poor, and the toner is hardened inside the printing apparatus, making it difficult to replenish. If the external additive is more than 1.0, the inside of the printing apparatus The agglomerates are generated at the development site, and a good image cannot be obtained.

  The transfer sheet is formed by, for example, forming an adhesive layer and a resin layer sequentially from a mount layer made of paper. That is, when the toner image layer is formed on the outermost surface of the transfer sheet as in Patent Documents 4 to 8, there is no glaze layer in the same layer as the image layer or in the lower layer (ceramic product side), and the image is formed on the resin layer. A layer is formed. The glue layer is a layer for bonding the mount, but if an image layer is formed on the glue layer with severe irregularities, it will become a rough image as it is, or a large amount when trying to improve the rough image (high gloss) Of toner.

  In order to improve this, the transfer sheet of the present invention has a resin layer formed on the adhesive layer. By this resin layer, the unevenness of the adhesive layer is leveled, and a good image layer with high glossiness is formed with a small amount of toner. In addition, the resin layer is surely transferred to the ceramic product because the unevenness on the ceramic product side is leveled during burning and does not exist after burning, and a cover sheet described later covers the image layer and the image layer Since the movement of the toner in the image layer is restricted until printing on the ceramic product, the image is not broken.

  The reason why the content ratio of the glue layer and the resin layer is set to 5: 7 to 10 is that if the resin layer is lower than 7, the uniformity of the image layer by the toner becomes insufficient, and white spots are likely to occur. If the number of layers exceeds 10, the rigidity of the entire transfer sheet is increased and bent, and the electrical resistance is increased and the image density is decreased (thin).

  The cover sheet is formed, for example, by forming a layer containing at least a glaze on a base material layer made of paper. In the present invention, the glaze is used only for the cover sheet. The reason for this is as follows. Conventionally, the glaze that flows as described above exists between the ceramic product and the image layer, or in the same layer as the image layer. Therefore, the glaze flows with the image layer accompanying the flow of the glaze during baking. The image collapsed.

  Therefore, in the present invention, the glaze is contained in the cover sheet located on the surface of the image layer, that is, the structure in which the glaze is present in the upper layer of the image layer. By doing so, the conventional problem is solved as follows.

  In the transfer sheet, the image layer and the resin layer are transferred to the ceramic product, and the resin layer is burnt and disappears by subsequent baking, and as a result, the image layer is baked on the ceramic product. On the ceramic product side of the image layer, it is transferred to the ceramic product via the resin layer (evening the unevenness on the surface of the ceramic product), and the image layer is directly baked onto the ceramic product by baking at the time of baking. Become. At this time, the glaze on the cover sheet also tries to flow, but the image layer does not collapse because there is no image layer baked on the ceramic product.

  As the cover sheet, if it contains glaze, a layer obtained by kneading glaze and oil may be formed on the base material layer, and the upper layer of the layer obtained by kneading glaze and oil on the base material layer. A flux layer may be formed on the side.

  By using a layer in which the glaze and oil are kneaded, a layer in which the glaze is made more uniform using oil as a dispersion medium can be formed, and the entire region including the image layer on the transfer sheet can be covered. In addition, by forming a glaze layer on the base material layer and a glaze layer on the upper side of the glaze layer, an object that contacts the flux layer (particularly the glaze of the surface layer part originally present in the ceramic product) The layer containing the glaze acts on the surface of the ceramic product.

  In the present invention, the toner is formed on the resin layer of the transfer sheet on which the adhesive layer and the resin layer are formed in order from the mount layer by the printing apparatus using the toner including the resin, the inorganic pigment, and the external additive. An image layer of a printed image is formed, and the layer containing the glaze of the cover sheet on which a layer containing at least a glaze is formed on the base material layer is brought into contact with the image layer of the transfer sheet, and the transfer sheet is used by a laminator. And the cover sheet are integrated, and then only the base material layer is removed from the cover sheet and the transfer layer is formed by removing the glue layer and the mount layer from the transfer sheet. It is carried out by a method of transferring to a ceramic product and baking.

  The reason for using a laminator when integrating the transfer sheet and cover sheet in the above method is that there is no unevenness or difference in work skill compared to the silk screen method or spray method, and it can be integrated easily and consistently. This is because an appropriate pressure can be applied to the transfer sheet and the cover sheet, and the movement of the image layer is also reliably suppressed at this stage.

  By suppressing the movement of the image layer in this manner, the resin layer disappears before the flow of the glaze in the transfer layer, and the image layer is baked and fixed on the ceramic product during the subsequent baking. Therefore, even if the glaze flows later, the image layer does not flow.

  In the ceramic image forming system of the present invention, in the above method, in the printing apparatus, the fixing temperature of the toner to the transfer sheet is set to 160 to 180 ° C. and the transfer speed of the transfer sheet is set to 70 to 70 corresponding to the fixing temperature. In the laminator, the heating temperature for integrating the transfer sheet and the cover sheet is set to 150 to 160 ° C., and the feed rate is set to 0.40 to 0.60 mm / second corresponding to the heating temperature. It is set to sec, and may be implemented as a setting in which the temperature is increased at 100 to 200 ° C./hour with respect to a peak temperature of 800 to 950 ° C. in a furnace for baking the transfer layer onto the ceramic product.

  In the above method, the reason why the fixing temperature of the printing apparatus is set to 160 to 180 ° C. and the transfer sheet feeding speed is set to 70 to 100 mm / sec corresponding to the fixing temperature is as follows. If the temperature is lower than 160 ° C., even if the feeding speed is reduced to 70 mm / sec, the toner is not fixed on the transfer sheet, and in some cases, the toner may be peeled off only by rubbing. On the other hand, if the temperature is higher than 180 ° C., even if the feeding speed is increased to 100 mm / sec, the toner may melt by heat and bleed on the transfer sheet and become dirty.

  In the above method, the heating temperature of the laminator is set to 150 to 160 ° C. and the feed rate is set to 0.40 to 0.60 mm / sec corresponding to the heating temperature as follows. If the temperature is lower than 150 ° C., the layer containing the glaze on the cover sheet may not be fixed to the image layer and the resin layer on the transfer sheet even if the feeding speed is reduced to 0.40 mm / sec. . On the other hand, if the temperature is higher than 160 ° C., the resin layer on the transfer sheet may be melted at this stage even if the feed temperature is increased to 0.60 mm / sec.

  In the above method, the reason why the furnace is set to increase the temperature at 100 to 200 ° C./hour with respect to the peak temperature of 800 to 950 ° C. is as follows. When the temperature is lower than 800 ° C., the image layer cannot be baked onto the ceramic product, and when the temperature is higher than 950 ° C., the toner (image layer) is burned and decolored or darkened. On the other hand, if the temperature is increased at a rate slower than 100 ° C./hour, it takes time to complete baking, and if the temperature is increased at a rate faster than 200 ° C./hour, the ceramic product may be cracked due to a rapid temperature change.

  In the following, the difference in effect between the “Example” to which the ceramic image forming system of the present invention is applied and the “Comparative Example” that is not so will be described. The experimental conditions excluding Comparative Examples 5 and 6 were the same as those in the method of claim 3 subordinate to claim 2 of the present invention, except for the configuration for experiment.

  That is, an image layer of a print image made of toner is formed on the resin layer of the transfer sheet by a printing apparatus in which the toner fixing temperature is set to 170 ° C. and the transfer sheet feed speed is set to 100 mm / sec, for example. The transfer sheet and the cover sheet are integrated by a laminator with a heating temperature set to, for example, 160 ° C. and a feed rate set to, for example, 0.60 mm / sec. After forming the transfer layer, the transfer layer is formed into a ceramic product. For example, the image is transferred and baked in a furnace set at a temperature of, for example, 200 ° C./hour with respect to a peak temperature of 850 ° C.

(toner)
Example 1 and Comparative Examples 1 and 2 are comparisons regarding toner. Example 1 is a toner to which the ceramic image forming system of the present invention is applied, Comparative Example 1 is a toner containing a flux, and Comparative Example 2 is a toner containing a glaze.

  In Example 1, for each color component of black, yellow, cyan, and magenta, styrene acrylic as a resin, inorganic pigment (ceramic pigment) as a pigment, and acrylic fine powder as an external additive, for example, 100: 40 (40 to 110) : Toner contained at a ratio of 1.0 (0.5 to 1.0).

  On the other hand, Comparative Example 1 includes usable fluxes such as alkali metals such as lithium and potassium, hydroxides such as alkaline earth metals such as magnesium and calcium, oxides and composites thereof, In this example, the toner contains, for example, a flux containing sodium hydroxide as a component and an inorganic pigment of each color component in a mixing ratio of 1: 1.

  Further, in Comparative Example 2, as glazes, usable materials include, for example, a single material or a mixture of titanium oxide, tungsten oxide, vanadium pentoxide, tin oxide, calcium fluoride, etc. as a basic material. For example, a toner containing a glaze containing zirconium silicate as a component and an inorganic pigment of each color component in a mixing ratio of 1: 1.

  When the toners of Example 1 and Comparative Examples 1 and 2 were used in the above method except for the toner conditions, the following results were obtained. In Example 1, a good result with high reproducibility was obtained without distorting the image and without reducing the density with respect to the original image.

  In Comparative Example 1, the image was destroyed at the lamination stage, and the density was lowered due to the decrease in the ratio of the pigment component, resulting in poor reproducibility.

  In Comparative Example 2, the image collapses at the stage of printing, and the density becomes low as in the Comparative Example. In addition, since the glaze component destabilizes the chargeability of the toner, the original white portion is particularly near the glaze component. The result was low reproducibility, such as coloring.

(Transfer sheet)
Example 2 and Comparative Examples 3 and 4 are comparisons of transfer sheets. In Example 2, the ceramic image forming system of the present invention is applied, and the content ratio of the resin layer containing, for example, a glue layer coated with a dextrin solution, for example, an alkyl acetalized polyvinyl alcohol, in order from the backing layer made of paper is 5 g / The transfer sheet is m ² , 9 g / m ² (5: 7 to 10), the thickness is 2 μm (1 to 2 μm) in this example, and 17 μm (15 to 20 μm) in this example.

  Comparative Example 3 is a transfer sheet in which, for example, a 10 μm glaze layer containing silicon dioxide as a component is formed on the mount layer, and Comparative Example 4 is a transfer sheet in which only the glue layer is formed on the mount layer.

  When the transfer sheets of Example 2 and Comparative Examples 3 and 4 were used in the above method except for the conditions of the transfer sheet, the following results were obtained. In Example 2, good results were obtained without distorting the image. In Comparative Example 3, the entire transfer sheet had high rigidity, and the end portion was broken or cracked. In Comparative Example 4, the toner was not burned in the dark color portion of the image layer, and white spots were generated.

(Cover sheet)
Examples 3 and 4 and Comparative Examples 5 and 6 are comparisons with respect to the coating layer (in the present invention, a cover sheet). The comparison of this coating layer is different from the method of Comparative Examples 5 and 6 in which the cover sheet and transfer sheet based on the above methods of Examples 3 and 4 are integrated by a laminator, and Comparative Example 5 is a silk screen. The comparative example 6 employs a spray method.

  In Examples 3 and 4, the ceramic image forming system of the present invention is applied. In Example 3, 10 μm containing a glaze in which a glaze containing, for example, silicon dioxide as a component and a silicone oil, for example, is mixed on a base material layer. It is a cover sheet in which a layer of thickness is formed.

  Example 4 is a cover sheet in which a 5 μm flux layer containing, for example, lead oxide as a component is formed on an upper layer of the above-mentioned layer obtained by kneading the glaze and oil.

  In Comparative Example 5, for example, a coating agent composed mainly of lead oxide and silicone oil was applied on the image layer by a silk screen method so that the coating layer was approximately 30 μm (calculated on the coating amount and the like) to form a coating layer. In Comparative Example 6, for example, a flux containing calcium oxide as a component was sprayed onto the image layer by spraying (calculated from the spraying time and spraying amount) to be approximately 20 μm to form a coating layer.

  In Example 3, a ceramic product having a slightly glossy surface and retaining a beautiful image could be obtained. In Example 4, it was possible to obtain a ceramic product having a beautiful image with a gloss more glossy than that of Example 3.

  On the other hand, in Comparative Examples 5 and 6, the toner was not fixed to the ceramic product and peeled off during baking. This is probably because the glaze layer is not protected. Individually, Comparative Example 5 required overnight (about 10 hours) for drying after coating, and after baking on the ceramic product, irregularities were generated on the surface of the ceramic product. Comparative Example 6 is visually clean immediately after coating, but unevenness in the surface gloss after baking on ceramic products may occur, and drops accumulated on the spray nozzle part of the spray may fall. Inefficient.

  It should be noted that the conditions of the setting range in the ceramic image forming method of the present invention and the experimental results about the case outside the setting range are as described above for the reasons of limiting each numerical value in the ceramic image forming method of the present invention. Omit.

  In the present invention, the present invention is limited to ceramic products. However, the present invention can also be applied to image formation of, for example, enamel products and glass products, for example, by applying a pattern by baking.

Claims (3)

  A cover sheet comprising: a toner used in an electrophotographic printing apparatus; a transfer sheet on which an image layer composed of a toner image is formed by the printing apparatus; and a cover sheet that protects the image layer on the transfer sheet. In a ceramic image forming system in which an image layer of a transfer sheet protected by a ceramic product is printed on a ceramic product, a resin, an inorganic pigment, and an external additive are used as the toner in a ratio of 100: 40 to 110: 0.5 to 1.0. The transfer sheet in which the toner is contained in a proportion, the transfer sheet in which the paste layer and the resin layer are laminated in the content ratio of 5: 7 to 10 in order from the mount layer is used as the transfer sheet, and the substrate is used as the cover sheet. A ceramic image forming system using a cover sheet in which a layer containing at least a glaze is formed on the layer.   A ceramic image forming method in which an image formed by an electrophotographic printing apparatus is printed on a ceramic product, the printing apparatus using a toner composed of a resin, an inorganic pigment, and an external additive, an adhesive layer in order from a mount layer, A layer containing the glaze of a cover sheet in which an image layer of a printed image made of toner is formed on the resin layer of the transfer sheet on which the resin layer is formed, and a layer containing at least a glaze is formed on the base material layer Is brought into contact with the image layer of the transfer sheet and the transfer sheet and the cover sheet are integrated by a laminator, and then only the base material layer is removed from the cover sheet and the glue layer and the mount layer are removed from the transfer sheet. A ceramic image forming method, comprising: forming a transfer layer by removing the resin layer, transferring the resin layer of the transfer layer to a ceramic product, and baking it.   In the printing apparatus, the fixing temperature of the toner to the transfer sheet is set to 160 to 180 ° C., and the transfer speed of the transfer sheet is set to 70 to 100 mm / sec corresponding to the fixing temperature. In the laminator, the transfer sheet and the cover sheet Is set to 150 to 160 ° C., and the feed rate is set to 0.40 to 0.60 mm / sec corresponding to the heating temperature, and the furnace for baking the transfer layer on the ceramic product is 800. The ceramic image forming method according to claim 2, wherein the temperature is set to 100 to 200 ° C./hour with respect to a peak temperature of ˜950 ° C.