JP2016029224A - Dyeing method, mask forming apparatus, and method for manufacturing colored article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To appropriately color an object formed of a flexible resin.SOLUTION: A dyeing method which dyes a flexible resin by a dye liquid containing a dye includes: a mask forming step S104 of forming a mask covering a region which is not colored by a dye liquid, on the surface of an object of a dye formed of a flexible resin; a dye liquid immersing step S106 of immersing the object on which the mask is formed into the dye liquid; and a mask peeling step S108 of peeling the mask from the object.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a dyeing method, a mask forming apparatus, and a colored product manufacturing method.

  Conventionally, flexible resins having flexibility (for example, synthetic rubber, urethane rubber, etc.) have been used for various purposes. For example, TPU (thermoplastic polyurethane) and the like are widely used for sports shoes and covers for portable devices.

Internet URL http://www.mimaki.co.jp

  In some cases, a flexible resin is more likely to cause yellowing or dirt adhesion than a hard resin, for example. For example, when a resin such as TPU is used for a long period of time, yellowing or dirt may easily occur depending on the application.

  On the other hand, for example, if the surface of the resin is colored, it is considered that yellowing or dirt can be made inconspicuous. Conventionally, for example, an ink jet printer using an ultraviolet curable ink has been widely used (see, for example, Non-Patent Document 1). If an ultraviolet curable ink is used, a color ink can be used against a resin such as TPU. Thus, coloring can be performed directly by an ink jet method. In this case, for example, by performing printing based on an image prepared in advance, it is possible to perform coloring with various designs.

  However, when the resin is colored with ultraviolet curable ink, the ink is cured in a state of being placed on the surface of the resin. Therefore, in this case, unevenness corresponding to the thickness of the ink is generated on the surface of the resin. If such irregularities occur, the ink may be easily peeled off when a product made of resin is used. Further, for example, in the case of a flexible resin, there is a possibility that the ink is easily peeled off due to deformation of the resin or the like. Therefore, depending on the use of the resin, a method of directly coloring by an ink jet method may not be suitable.

  Further, as a method for coloring the resin, a method using a dye solution containing a dye is also conceivable. If such a method is used, for example, coloring having high durability can be appropriately performed.

  However, when coloring is performed using a dye solution, the entire coloring object is usually colored. Therefore, in this case, for example, it becomes difficult to express a fine design or the like. Therefore, conventionally, a method of coloring a flexible resin by a more appropriate method has been desired. Then, an object of this invention is to provide the dyeing | staining method, mask formation apparatus, and the manufacturing method of a colored product which can solve said subject.

  The inventor of the present application has earnestly studied a method for coloring a flexible resin such as TPU. Then, for example, it is considered that a coloring mask is formed by an ink jet method, not a method of directly coloring by color ink using an ink jet method, and a region not covered with the mask is colored with a dye solution. It was. If comprised in this way, a fine design etc. can be expressed appropriately, for example, also when using a dye solution. Further, by removing the mask after coloring, it is possible to prevent unevenness due to ink from occurring on the colored surface. Further, the inventors of the present application have found a more preferable specific configuration and the like regarding the case where coloring is performed by such a method, through further intensive research. In order to solve the above problems, the present invention has the following configuration.

  (Structure 1) A dyeing method for dyeing a flexible resin with a dye solution containing a dye, and a region on the surface of an object to be dyed formed with a flexible resin that is not colored with the dye solution A mask forming step of forming a mask covering the substrate, a dye solution immersing step of immersing the object on which the mask is formed in the dye solution, and a mask peeling step of detaching the mask from the object.

  In the case of such a configuration, for example, by forming a mask and performing coloring, it is possible to select a part of the region to be dyed and appropriately perform coloring. In addition, for example, a fine design or the like can be appropriately expressed using, for example, a dye solution.

  Moreover, when comprised in this way, since a mask is peeled in a mask peeling step, for example, after completion of coloring, extra unevenness or the like does not remain on the surface of an object. Therefore, if comprised in this way, the surface of the target object of the state which coloring completed can be planarized appropriately, for example. Thereby, for example, coloring with high durability can be appropriately performed on an object formed of a flexible resin.

  The flexible resin is, for example, a soft synthetic resin. The flexible resin may be, for example, an elastic synthetic resin (such as synthetic rubber). More specifically, as the flexible resin, a urethane-based resin (urethane rubber or the like) can be preferably used. Moreover, as a urethane-type resin, TPU can be used suitably, for example. It is also conceivable to use other synthetic rubbers as the flexible resin.

  (Configuration 2) The flexible resin is thermoplastic polyurethane. If comprised in this way, it can color more appropriately with respect to the target object of dyeing | staining, for example.

  (Structure 3) The mask forming step forms a mask that can be peeled off by alcohol, and the mask peeling step involves immersing at least a portion of the object on which the mask is formed in a liquid containing alcohol to remove the mask from the object. Peel off.

  If comprised in this way, a mask can be appropriately removed, without giving a big damage to resin by using the mask which can be peeled with alcohol, for example. Thereby, for example, it is possible to more appropriately color an object to be dyed.

  It should be noted that removing the mask from the object by immersing it in a liquid containing alcohol means, for example, that the mask is easily peeled off by immersing at least a part of the object in which the mask is formed in a liquid containing alcohol. The mask may be peeled off. More specifically, for example, the mask may be peeled after the object is immersed in a liquid containing alcohol for a predetermined time.

  (Configuration 4) In the mask formation stage, a mask is formed using an inkjet head that discharges droplets of an ultraviolet curable liquid that is a liquid containing a monomer that is polymerized by ultraviolet irradiation, and an ultraviolet light source that irradiates ultraviolet rays. A mask is formed by ejecting droplets from the ink jet head to the power region, and the ultraviolet curable liquid contains substantially only a monofunctional monomer as a monomer that is polymerized by irradiation with ultraviolet rays.

  If comprised in this way, the mask which covers a desired area | region can be formed more appropriately with high precision by forming a mask with an inkjet system, for example. Thereby, for example, it is possible to more appropriately color an object to be dyed.

  Further, in this case, since the monomer contained in the ultraviolet curable liquid serving as the mask material is a monofunctional monomer, a single molecular chain is formed by the polymerization reaction. In this case, it is considered that the influence of the solvent is likely to occur, compared to the case where, for example, a net-like dense molecular chain is formed. More specifically, for example, in the case of such a configuration, it is considered that swelling due to alcohol is likely to occur, and the mask is easily peeled off by alcohol.

  Therefore, if comprised in this way, the mask which can be peeled with alcohol can be formed more appropriately, for example. Thereby, for example, it is possible to more appropriately color an object to be dyed.

  In addition to the monofunctional monomer, a bifunctional monomer is also known as a monomer that is polymerized by irradiation with ultraviolet rays. For example, conventionally, a bifunctional monomer such as hexamethylene diacrylate may be used as a component of an ultraviolet curable ink.

  However, bifunctional monomers form a network structure when polymerized. Therefore, for example, when the mask is formed with a liquid containing a monomer having a bifunctional group, it is considered that the structure of the mask becomes dense and hardly dissolves in the solvent. As a result, when the ultraviolet curable liquid serving as a mask material contains a bifunctional monomer, it is considered difficult to form a mask that can be peeled off by alcohol.

  In addition, when a mask is formed using a monomer having a bifunctional group, a dense mask is formed, so that the mask may become harder. However, when the mask is formed on a flexible resin, if the mask is hard, the mask may be easily peeled off when the resin is deformed.

  On the other hand, when comprised as mentioned above, for example, by forming a mask only with a monomer of a monofunctional group, a mask that can be more easily peeled off by alcohol can be appropriately formed. In addition, a mask with higher flexibility can be formed as compared with a case where a mask is formed using a bifunctional monomer. Therefore, if comprised in this way, it can prevent appropriately that a mask peels by deformation | transformation etc. of resin etc., for example. Thereby, for example, a mask suitable for a flexible resin can be more appropriately formed.

  (Configuration 5) The ultraviolet curable liquid contains an acrylate ester as a monofunctional monomer. If comprised in this way, the mask which can be peeled with alcohol can be formed more appropriately, for example.

  (Configuration 6) The image forming apparatus further includes a fixing solution immersion step of immersing the object in a fixing solution that is a liquid containing a fixing agent that fixes the dye to the object. For example, the fixing solution immersion step may be a step performed between the dye solution immersion step and the mask peeling step. If comprised in this way, the color transfer etc. after coloring can be prevented appropriately, for example. Thereby, for example, it is possible to more appropriately color an object to be dyed. The fixing solution immersion step may be a step performed after the mask peeling step, for example.

  (Configuration 7) The method further includes a coating layer forming step of forming a coating layer covering the surface of the object from which the mask has been peeled off. When comprised in this way, the area | region colored in the target object can be protected appropriately, for example. Thereby, for example, color migration after coloring can be appropriately prevented. Therefore, if comprised in this way, it can color more appropriately with respect to the target object of dyeing | staining, for example.

  (Configuration 8) A plurality of types of dye solutions having different colors are used, and a mask formation step, a dye solution immersion step, and a mask peeling step are performed for each dye solution. If comprised in this way, the coloring by a several color can be performed appropriately, for example. Thereby, for example, it is possible to more appropriately color an object to be dyed.

  Here, in the case where the mask forming step, the dye solution immersion step, and the mask peeling step are repeated a plurality of times, for example, if the resin constituting the object is damaged during the peeling of the mask, the mask peeling step is performed a plurality of times. As a result, it is considered that the damage received by the resin also increases. On the other hand, when comprised in this way, since the mask is peeled off using a liquid containing alcohol, even if the mask is peeled off a plurality of times, damage to the resin can be suppressed appropriately. Therefore, when configured in this way, it can be said that a variety of designs can be appropriately expressed using a plurality of colors.

  In addition, it is preferable to make the area | region which a mask covers differ for every dye liquid, for example. If comprised in this way, more various designs can be expressed appropriately using a plurality of colors.

  (Configuration 9) The object is a material used as a sole of a shoe. The sole of this shoe is, for example, the sole of a sports shoe. If comprised in this way, it can color appropriately with respect to the sole of shoes, for example. Thereby, for example, a shoe sole with high design can be appropriately provided.

  (Configuration 10) The object is a material used as a cover of a mobile device. The cover of a portable device is a cover of a smart phone or a game machine, for example. If comprised in this way, it can color appropriately with respect to the cover of a portable apparatus, for example. Thereby, for example, a cover of a portable device with high design can be appropriately provided.

  (Structure 11) In the dyeing method according to any one of Structures 1 to 10, a mask forming apparatus for forming a mask at a mask forming stage, wherein the liquid is a liquid containing a monomer that is polymerized by irradiation with ultraviolet light. An ink jet head for ejecting liquid droplets of the liquid and an ultraviolet light source for irradiating ultraviolet light are used, and a mask is formed by ejecting liquid droplets from the ink jet head to a region where the mask is to be formed. If comprised in this way, a mask can be appropriately formed with high precision, for example. Thereby, for example, it is possible to more appropriately color an object to be dyed.

  (Structure 12) A method for producing a colored product, which is produced by dyeing a colored product obtained by coloring a flexible resin with a dye solution containing a dye, wherein the object to be dyed is formed of a flexible resin. A mask forming step for forming a mask covering a region not colored by the dye solution on the surface, a dye solution immersing step for immersing the object on which the mask is formed in the dye solution, and a mask for peeling the mask from the object A peeling step. If comprised in this way, the effect similar to the structure 1 can be acquired, for example.

  According to the present invention, for example, an object formed of a flexible resin can be appropriately colored.

It is a figure explaining the dyeing | staining method which concerns on one Embodiment of this invention. FIG. 1A is a flowchart showing an example of a staining method. FIG. 1B shows an example of the configuration of the main part of the inkjet printer 10 used when the dyeing method of this example is executed. It is a figure explaining in more detail about dye liquid immersion step S106. Fig.2 (a) is a schematic diagram which shows an example of the mode of the target object 50 before being immersed in a dye liquid. FIG. 2B is a photograph showing the staining solution used in this example. It is a figure explaining in more detail about mask peeling step S108. FIGS. 3A, 3B, and 3C are photographs showing operations performed in the mask peeling step S108. It is a whole photograph which shows the example of the state which coloring completed. FIG. 4A shows two examples of the state after coloring when the dyeing time for immersing the object in the dye solution is about 45 minutes to 1 hour. FIG. 4B shows two examples of the state after coloring when the staining time is about 2 hours. It is an enlarged photograph which shows the state after coloring in more detail. FIGS. 5A, 5B, and 5C show details of each portion of the cover for smart fins colored in the present embodiment.

  Hereinafter, embodiments according to the present invention will be described with reference to the drawings. FIG. 1 is a diagram for explaining a staining method according to an embodiment of the present invention. FIG. 1A is a flowchart showing an example of a staining method. FIG. 1B shows an example of the configuration of the main part of the inkjet printer 10 used when the dyeing method of this example is executed.

  The dyeing method executed in this example is a method of dyeing a flexible resin with a dye solution containing a dye. This dyeing method can be considered as a method for producing a colored product colored with a flexible resin. In this case, the flexible resin is, for example, a soft synthetic resin. The flexible resin may be, for example, a synthetic resin having elasticity. More specifically, a case where TPU (thermoplastic polyurethane) is used as the flexible resin will be described below. TPU is an example of a urethane-based resin. In addition, it is conceivable to use a resin other than a urethane-based resin as the flexible resin. For example, it is possible to use silicon resin (silicon rubber), isoprene rubber (IR), styrene-butadiene rubber (SBR), etc. as the flexible resin.

  In the dyeing method of this example, dyeing is performed by performing the operations of the preparation stage S102, the mask formation stage S104, the dye solution immersion stage S106, and the mask peeling stage S108. Hereinafter, the operation at each stage will be described.

  The preparation step S102 is a step of preparing an object to be dyed, and a material or the like formed of a flexible resin is prepared as an object to be dyed. In this case, the material or the like is, for example, a material or the like used in a product or part manufacturing process.

  More specifically, for example, a material used as a sole of a shoe or a material used as a cover of a mobile device may be used as the coloring object. In this case, the sole of the shoe is, for example, the sole of a sports shoe. The cover of a portable device is a cover of a smart phone or a game machine, for example. In addition, as the coloring object, other materials such as a wristwatch belt portion, swimming goggles, fins, and a cutting board may be used. By coloring these materials as described below, it is possible to provide products, parts, and the like with high designability.

  The mask formation step S104 is a step of forming a mask on the surface of the object to be dyed. In this case, a mask is a layer which covers the area | region which does not color with dye liquid, for example. In the mask formation step S104 of this example, a mask is formed by an ink layer using the ink jet printer 10. Thereby, the inkjet printer 10 is used as a mask forming apparatus for forming a mask.

  As shown in FIG. 1B, the ink jet printer 10 used in this example includes an ink jet head 12, an ultraviolet light source 14, and a base portion 16. The inkjet head 12 discharges liquid droplets (ultraviolet curable liquid) containing a monomer that is polymerized by irradiation with ultraviolet rays. The ultraviolet light source 14 is a light source that irradiates ultraviolet rays. Further, the base 16 is a base-like member that supports the object 50 in a state of being opposed to the inkjet head 12. The base 16 may be a platen of the inkjet printer 10, for example.

  As the ink jet printer 10, for example, a known ink jet printer can be used. More specifically, as the ink jet printer 10, for example, an ink jet printer for ultraviolet curable ink (UV ink) manufactured by Mimaki Engineering Co., Ltd. can be suitably used.

  In addition, with this configuration, in this example, the inkjet head 12 performs a main scanning operation (scanning) for ejecting liquid droplets while moving in a preset main scanning direction, so that the liquid droplets serving as a mask material are discharged. And discharged onto the object 50. In this case, the inkjet head 12 selectively ejects liquid droplets to a predetermined position on the object 50 in accordance with, for example, an instruction from a control unit (not shown) of the inkjet printer 10. Further, by performing a sub-scanning operation as necessary, a region on the target object 50 that is a droplet discharge target is changed. In this case, the sub-scanning operation is, for example, an operation in which the inkjet head 12 moves relative to the object 50 in the sub-scanning direction orthogonal to the main scanning direction. As a result, the inkjet head 12 discharges liquid droplets serving as a mask material to a region where a mask is to be formed.

  Moreover, the ultraviolet light source 14 polymerizes the monomer in the liquid by irradiating the applied liquid on the object 50 with ultraviolet light by the inkjet head 12. Accordingly, the inkjet head 12 and the ultraviolet light source 14 form a mask on the surface of the object 50. According to this example, for example, a mask covering a desired region can be appropriately formed with high accuracy by forming the mask by the inkjet method using the inkjet head 12.

  In this example, in the mask formation stage, a mask capable of being peeled off by alcohol is formed. In this case, as the liquid used as the mask material, for example, a known ultraviolet curable primer ink having a preferable characteristic can be selected and used.

  More specifically, as the ultraviolet curable liquid used as a mask material, for example, it is preferable to use an ultraviolet curable liquid containing substantially only a monofunctional monomer as a monomer that is polymerized by ultraviolet irradiation. Moreover, as this monofunctional monomer, for example, an acrylate ester can be suitably used. More specifically, as such a liquid, for example, a PR100 type ink which is a primer ink manufactured by Mimaki Engineering Co., Ltd. can be suitably used.

  Here, the monofunctional monomer means, for example, a structure in which only one vinyl group is contained in one molecule of monomer. In addition, the UV curable liquid used as the mask material contains substantially only a monofunctional monomer as a monomer. For example, the UV curable liquid is a monomer except for a small amount of components. It contains only monomers of functional groups. More specifically, the phrase “substantially only a monofunctional monomer” may mean that, for example, 90% or more of the monomers contained in the ultraviolet curable liquid are monofunctional monomers. .

  Moreover, when the monomer contained in the liquid used as the mask material is a monofunctional monomer as in this example, one molecular chain is formed by the polymerization reaction. In this case, it is considered that the influence of the solvent is likely to occur, compared to the case where, for example, a net-like dense molecular chain is formed. More specifically, for example, in the case of such a configuration, it is considered that swelling due to alcohol is likely to occur, and the mask is easily peeled off by alcohol. Therefore, according to this example, it is possible to more appropriately form a mask that can be peeled off by alcohol, for example.

  Note that a mask that can be peeled off by alcohol is, for example, a mask that can be easily peeled off by being immersed in a liquid containing alcohol. More specifically, the mask that can be peeled off by alcohol may be, for example, a mask that is partially dissolved by alcohol. However, it is not always necessary to dissolve in alcohol. For example, the mask that can be peeled off by alcohol may be a mask that swells due to the influence of alcohol and that has poor adhesion to an object.

  Further, as a monomer that is polymerized by irradiation with ultraviolet rays, in addition to a monofunctional monomer, a bifunctional monomer is also known. For example, conventionally, a bifunctional monomer such as hexamethylene diacrylate may be used as a component of an ultraviolet curable ink. However, bifunctional monomers form a network structure when polymerized. For this reason, for example, when the mask is formed of an ultraviolet curable liquid containing a bifunctional monomer, it is considered that the mask structure becomes dense and hardly dissolves in the solvent. As a result, it is thought that it is difficult to swell against weak solvents such as alcohol. Therefore, when the liquid used as a mask material contains a bifunctional monomer, it is considered difficult to form a mask that can be peeled off by alcohol.

  In addition, when a mask is formed using a monomer having a bifunctional group, a dense mask is formed, so that the mask may become harder. However, when the mask is formed on a flexible resin, if the mask is hard, the mask may be easily peeled off when the resin is deformed.

  On the other hand, in the case of this example, for example, by forming a mask only with a monomer of a monofunctional group, a mask that can be easily peeled off by alcohol can be appropriately formed. In addition, a mask with higher flexibility can be formed as compared with a case where a mask is formed using a bifunctional monomer. Moreover, it can prevent appropriately that a mask peels by deformation | transformation etc. of resin etc. by this. Therefore, according to this example, a mask suitable for an object formed of a flexible resin can be more appropriately formed.

  The dye solution immersion step S106 is a step of coloring the object to be dyed, and the object on which the mask is formed is immersed in the dye solution. Thereby, the area | region where the mask is not formed in the target object is colored. In this case, the dye liquid is, for example, a liquid in which a dye is dissolved. Moreover, as a dye liquid, the well-known dye according to resin which comprises a target object can be used suitably, for example. More specifically, for example, when coloring an object composed of TPU, a known dye solution or the like for cotton products can be used. The operation of the dye solution immersion step S106 will be described in more detail later.

  The mask peeling step S108 is a step of peeling the mask from the object to be dyed, and the mask is peeled off by immersing at least a portion of the object on which the mask is formed in a liquid containing alcohol. In this case, removing the mask from the object by immersing it in a liquid containing alcohol means, for example, that the mask is easily peeled off by immersing at least the part of the object in which the mask is formed in the liquid containing alcohol. The mask may be peeled off. For example, in this example, in the mask peeling step S108, after the object is immersed in a liquid containing alcohol for a predetermined time, the mask is peeled from the object using an adhesive tape. The operation of the mask peeling step S108 will be described in detail later.

  By performing the operation at each stage as described above, in this example, the mask can be appropriately formed before the object to be dyed is immersed in the dye solution. In this case, by forming the mask by the ink jet method, the mask can be appropriately formed with high accuracy by the digital method in accordance with the image prepared in advance. And by coloring with a dye liquid using the formed mask, it can color appropriately by selecting a partial area | region with respect to the dyeing | staining object.

  Therefore, according to this example, a fine design or the like can be appropriately expressed by digital dyeing that combines mask formation by an ink jet method and coloring using a dye solution. Further, for example, since the mask is peeled off at the mask peeling stage, no extra unevenness or the like is generated on the surface of the colored object. Thereby, for example, the surface of the object in a state where coloring is completed can be appropriately flattened. Therefore, according to this example, it is possible to appropriately perform coloring with high durability on an object formed of a flexible resin.

  Here, a flexible resin such as TPU is more likely to be colored using a dye solution because, for example, a dye contained in the dye solution is likely to enter the inside as compared with a hard resin or the like. However, it is generally considered that liquids other than the dye liquid easily enter such a resin. As a result, the flexible resin may have lower chemical resistance than, for example, a hard resin.

  Therefore, when coloring a flexible resin using a mask, the resin may be easily damaged when the mask is peeled depending on the type of chemical used for peeling the mask. For example, when the mask is peeled off with a strong acid or alkali, the resin damage may increase. In addition, when the mask is removed using a highly soluble organic solvent such as toluene, for example, the resin constituting the object may be dissolved.

  On the other hand, in this example, by using a mask that can be peeled off by alcohol, the mask can be appropriately removed without damaging the resin. Therefore, according to this example, it is possible to more appropriately color an object formed of a flexible resin.

  The liquid containing alcohol is, for example, 100% pure alcohol containing only alcohol or an alcohol solution containing alcohol and water. As the liquid containing alcohol, for example, a liquid containing methanol as a main component can be suitably used. The liquid containing alcohol may be a mixed liquid of a plurality of types of alcohol. For example, the liquid containing alcohol may be a mixed liquid of methanol and ethanol. It is also conceivable to use a mixed solution of methanol, ethanol, and isopropanol. More specifically, fuel alcohol or the like can be suitably used as the liquid containing alcohol.

  Subsequently, the operation of the dye solution immersion step S106 and the mask peeling step S108 performed in the dyeing method of the present example will be described in more detail based on a specific coloring example (hereinafter referred to as an example). FIG. 2 is a diagram for explaining the dye solution immersion step S106 in more detail.

  Fig.2 (a) is a schematic diagram which shows an example of the mode of the target object 50 before being immersed in a dye liquid. In this example, the target object 50 before being immersed in the dye solution is the target object 50 on which the mask 102 is formed in the mask formation step S104.

  By forming the mask 102 in the mask formation step S <b> 104, the object 50 is in a state where the surface other than the colored region 104 on the surface is covered with the mask 102. In this case, the colored region 104 is a region that is colored with a dye solution. The colored region 104 is set in advance according to a design drawn on the surface of the object 50, for example.

  In this embodiment, as the object 50, a smart fin cover formed of TPU is used. The mask 102 was formed using a UJF-3042HG type inkjet printer manufactured by Mimaki Engineering. Further, PR100 type primer ink manufactured by Mimaki Engineering Co., Ltd. was used as an ultraviolet curable liquid used as a material for the mask 102. Then, a mask 102 was formed by printing an image for printing prepared in advance so that ink droplets were ejected onto a region where the object 50 was not desired to be colored. In addition, as this print image, a monochrome two-tone image indicating an area where the mask 102 is to be formed was used. More specifically, in this printing, printing is performed at a resolution of 720 × 1200 dpi using single-pass replacement in which only the primer ink is set as the color to be used, and multi-pass printing setting with 16 passes. It was.

  When the object is immersed in the staining solution for a long time, the mask 102 may be formed of a plurality of ink layers by further forming a second ink layer. In this case, for the second layer, it is conceivable to use a setting for setting the primer ink to 100% and the clear ink to 1% as the color replacement setting. In addition, for the second layer, it is preferable to set the conditions for ultraviolet irradiation to the conditions for thick printing. Similarly to the first layer, it is conceivable to perform printing at a resolution of 720 × 1200 dpi using a multi-pass print setting with 16 passes.

  FIG. 2B is a photograph showing the staining solution used in this example. In this example, the dye solution was prepared by dissolving the dyed powder in hot water (70 ° C.). Moreover, as the dyeing powder, New Multi-type high-temperature dyeing powder manufactured by Dairon Corporation was used. The solvent of the dye solution may be water instead of hot water. However, it is possible to dye in a shorter time by using hot water.

  In the dye solution immersion step S106, the colored region 104 of the object 50 is colored by immersing the object 50 on which the mask 102 is formed in such a dye solution. In this example, the time for immersing the object 50 in the dye solution (dyeing time) was about 45 minutes to 1 hour, or about 2 hours.

  FIG. 3 is a diagram for explaining the mask peeling step S108 in more detail. FIGS. 3A, 3B, and 3C are photographs showing operations performed in the mask peeling step S108. In this embodiment, in the mask peeling step S108, the portion of the object 50 where the mask 102 is formed is immersed in alcohol, and then the mask 102 is peeled off using an adhesive tape or the like. In such a case, for example, it is considered that a part of the primer ink constituting the mask 102 is dissolved by immersing the portion of the mask 102 in the object 50 in alcohol. In addition, it is considered that the mask 102 is easily peeled off with an adhesive tape or the like.

  More specifically, in the mask peeling step S108, first, as shown in FIG. 3A, alcohol is poured into a container (plastic container or the like) having a size matched to the object 50. In this example, fuel alcohol manufactured by Ken A Co., Ltd. was used as the alcohol. This alcohol contains 76.6% methanol, 21.4% ethanol, and 0.3% isopropanol. Then, by putting the object 50 into the alcohol in the container, at least a portion of the object 50 where the mask 102 is formed is immersed in the alcohol. The time of immersion in alcohol is preferably about 1 to 2 minutes.

  Thereafter, the object 50 is taken out from the alcohol, and an adhesive tape is affixed on the mask 102 as shown in FIG. And as shown in FIG.3 (c), an adhesive tape is peeled off. Thereby, the mask 102 attached to the adhesive tape is peeled off from the object 50.

  In this way, for example, the mask 102 can be appropriately peeled from the object 50. Further, for example, the surface of the object 50 can be appropriately prevented from being damaged as compared with the case where the mask 102 is directly peeled off by, for example, a method of rubbing the surface of the object 50 without using an adhesive tape or the like.

  Moreover, the coloring to the target object 50 is completed by peeling the mask 102 as mentioned above. 4 and 5 are photographs showing a state in which coloring is completed in this example.

  FIG. 4 is an overall photograph showing an example of a state in which coloring is completed, and shows a state after coloring of the cover for smart fin used as an object to be dyed. FIG. 4A shows two examples of the state after coloring when the dyeing time for immersing the object in the dye solution is about 45 minutes to 1 hour. FIG. 4B shows two examples of the state after coloring when the staining time is about 2 hours. In any example, it can be seen that coloring is appropriately performed with high accuracy in accordance with the design.

  In each of FIGS. 4A and 4B, the two types of examples show the results when different color dye solutions are used. More specifically, in FIG. 4A, the photograph on the left is the result when a yellow-green dye solution is used. The photograph on the right is the result when a blue dye solution is used. Further, in FIG. 4A, the photograph on the left is the result when a yellow dye solution is used. The photograph on the right is the result when a blue dye solution is used.

  FIG. 5 is an enlarged photograph showing the state after coloring in more detail. FIGS. 5A, 5B, and 5C show details of each portion of the cover for smart fins colored in the present embodiment.

  From each photograph, it can be seen that the present example is appropriately colored with high accuracy. Further, in this embodiment, since coloring is performed by dyeing and the mask is peeled off after the coloring, extra unevenness or the like does not remain on the surface after coloring. Therefore, for example, as shown in FIG. 5 (c), even if the smart fin cover is bent, there is no problem such as ink breakage. Further, since coloring is performed by dyeing, the friction resistance is sufficiently high. Therefore, according to the present Example, it turns out that it can color appropriately with high precision with respect to flexible resin, such as TPU.

  Moreover, in FIG.4 and FIG.5, the example at the time of coloring with a simple design is shown for convenience of illustration. However, when digital dyeing is performed using an ink jet head as in this embodiment, it is also possible to use a high-definition design including a finer pattern as a coloring design. More specifically, for example, the contents of a photograph can be expressed by forming a mask based on an image obtained by performing halftone dot processing on a photograph such as a natural object.

  Next, various modifications will be described with respect to the staining method described with reference to FIGS. The dyeing method according to the present invention is not limited to the specific examples described above, and various modifications can be considered. Except as described below, the operations performed in the various modifications are the same as or similar to the operations described with reference to FIGS.

  First, an example in the case of coloring with a plurality of colors will be described. When performing the operation in each step as in the configuration described with reference to FIG. 1, for example, the mask formation step S104, the dye solution immersion step S106, It is also conceivable that the series of operations in the mask peeling step S108 is repeated a plurality of times to perform coloring using a plurality of types of dye solutions. In this case, a plurality of types of dye solutions having different colors are used, and the mask formation step S104, the dye solution immersion step S106, and the mask peeling step S108 are performed for each dye solution. If comprised in this way, the coloring by a several color can be performed appropriately, for example. In this case, it is preferable that the area covered by the mask is different for each dye solution of each color, for example. If comprised in this way, more various designs can be expressed appropriately using a plurality of colors.

  Here, in the case where the mask formation step S104, the dye solution immersion step S106, and the mask peeling step S108 are repeated a plurality of times, for example, if the resin constituting the object is damaged when the mask is peeled, the mask peeling step S108. It is considered that the damage received by the resin is increased by carrying out the process multiple times. On the other hand, when comprised like this modification, since the mask is peeled off using a liquid containing alcohol, even if the mask is peeled off a plurality of times, damage to the resin can be suppressed appropriately. Therefore, in this respect, it can be said that more various designs can be appropriately expressed using a plurality of colors.

  Further, in a further modification, for example, it is conceivable to perform an operation other than each stage shown in FIG. Further, as such a modification, for example, in the dyeing method, it is conceivable to further perform an operation at the fixing solution immersion stage. In this case, the fixing solution immersion step is a step of immersing the object in a fixing solution that is a liquid containing a fixing agent that fixes the dye to the object to be dyed.

  As the fixing solution, a known fixing solution corresponding to the dye to be used can be suitably used. The fixing solution may be a dyeing stopper solution, for example. The fixing solution immersion step may be a step performed between the dye solution immersion step S106 and the mask peeling step S108, for example. If comprised in this way, the color transfer etc. after coloring can be prevented appropriately, for example. Further, the fixing solution immersion step may be an operation performed after the mask peeling step S108, for example.

  Further, in the dyeing method, in addition to the steps shown in FIG. 1A, for example, it is conceivable to further perform an operation in a coating layer forming step. In this case, the coating layer forming step is, for example, a step of forming a coating layer that covers the surface of the object from which the mask has been peeled off in the mask peeling step S108. When comprised in this way, the area | region colored in the target object can be protected appropriately, for example. Thereby, for example, color migration after coloring can be appropriately prevented.

  The coating layer can be formed by using, for example, a known clear ink by the inkjet printer 10. In this case, more specifically, for example, it is conceivable to use an ultraviolet curable ink having flexibility after curing. The ultraviolet curable ink having flexibility after curing is, for example, ink having a property of extending after curing. With this configuration, for example, even when the flexible resin is deformed, the coating layer can be appropriately deformed in accordance with the deformation of the resin. Thereby, for example, the coating layer due to deformation of the resin can be appropriately prevented from being cracked or peeled off.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above embodiment. It is apparent from the description of the scope of claims that embodiments with such changes or improvements can be included in the technical scope of the present invention.

  The present invention can be suitably used for, for example, a staining method.

DESCRIPTION OF SYMBOLS 10 ... Inkjet printer, 12 ... Inkjet head, 14 ... Ultraviolet light source, 16 ... Base part, 50 ... Object, 102 ... Mask, 104 ... Colored area

Claims (12)

A dyeing method for dyeing a flexible resin with a dye solution containing a dye,
A mask forming step of forming a mask covering a region not colored by the dye solution on the surface of an object to be dyed formed of the flexible resin;
A dye solution immersion step of immersing the object on which the mask is formed in the dye solution;
And a mask peeling step for peeling the mask from the object.   The dyeing method according to claim 1, wherein the flexible resin is thermoplastic polyurethane. The mask forming step forms the mask capable of being peeled off by alcohol,
3. The mask removal step according to claim 1, wherein in the mask peeling step, the mask is peeled from the object by immersing at least a portion of the object on which the mask is formed in a liquid containing alcohol. 4. The staining method according to 1. The mask forming step includes
An inkjet head that discharges droplets of an ultraviolet curable liquid that is a liquid containing a monomer that is polymerized by irradiation of ultraviolet rays; and
Using an ultraviolet light source that irradiates ultraviolet rays, by discharging the droplets from the inkjet head to a region where the mask is to be formed, the mask is formed,
The dyeing method according to claim 3, wherein the ultraviolet curable liquid contains substantially only a monofunctional monomer as a monomer that is polymerized by the irradiation of ultraviolet rays.   The dyeing method according to claim 4, wherein the ultraviolet curable liquid contains an acrylate ester as the monomer of the monofunctional group.   The dyeing method according to any one of claims 1 to 5, further comprising a fixing solution immersing step of immersing the object in a fixing solution which is a liquid containing a fixing agent for fixing the dye to the object. .   The dyeing method according to any one of claims 1 to 6, further comprising a coating layer forming step of forming a coating layer covering the surface of the object from which the mask has been peeled off. Using a plurality of types of the dye solutions having different colors,
The dyeing method according to claim 1, wherein the mask forming step, the dye solution immersing step, and the mask peeling step are performed for each of the dye solutions.   The dyeing method according to claim 1, wherein the object is a material used as a sole of a shoe.   The staining method according to claim 1, wherein the object is a material used as a cover of a portable device. The dyeing method according to any one of claims 1 to 10, wherein the mask forming apparatus performs the formation of the mask at the mask forming stage.
An inkjet head that discharges droplets of an ultraviolet curable liquid that is a liquid containing a monomer that is polymerized by irradiation of ultraviolet rays; and
An ultraviolet light source for irradiating ultraviolet rays,
A mask forming apparatus, wherein the mask is formed by discharging the droplets from the inkjet head to a region where the mask is to be formed. A method for producing a colored product produced by dyeing a colored product obtained by coloring a flexible resin with a dye solution containing a dye,
A mask forming step of forming a mask covering a region not colored by the dye solution on the surface of an object to be dyed formed of the flexible resin;
A dye solution immersion step of immersing the object on which the mask is formed in the dye solution;
And a mask peeling step for peeling the mask from the object.