JP2014141043A - Water pressure transfer film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water pressure transfer film that is subjected to ink jet printing hardly causing a transfer failure such as a pattern skew in a transfer step being a later step.SOLUTION: An ink layer of a water pressure transfer film 1 includes a pattern 31 for being transferred to matter subject to transfer, and low-density printing 33 that is an area not to be transferred to the matter subject to transfer and that has a density lower than a density of the pattern 31. Thus, a skew of the pattern 31 is reduced, and accurate positioning transfer can be performed.

Description

  The present invention relates to, for example, a hydraulic transfer film used in a hydraulic transfer method in which a design is imparted by transferring a design to a molded product having a three-dimensional surface or a curved surface with unevenness.

  The hydraulic transfer method is known as a technique capable of imparting a design rich in design to a molded article having an uneven solid surface or curved surface (for example, Japanese Patent No. 2757346 (Patent Document 1)).

  Conventionally, in the production of a hydraulic transfer film used in the hydraulic transfer method, a method of forming a pattern by a printing means such as gravure printing on a water-soluble or water-swellable film such as a polyvinyl alcohol film as a support is adopted. It had been.

  However, with the recent increase in demand for multi-product small-lot production, a method of forming a pattern by an ink-jet method has attracted attention (for example, Japanese Patent No. 395748 (Patent Document 2)).

  In addition, with the diversification of user needs, there is an increasing demand for applying a predetermined pattern to a predetermined part of an object (so-called positioning transfer), and in order to make this possible, the transferred work and water surface There has been proposed a method of detecting a shift of both of the upper films and correcting the transfer position (for example, Japanese Patent Application Laid-Open No. 2008-213428 (Patent Document 3)).

Japanese Patent No. 2757346 Japanese Patent No. 3952748 JP 2008-213428 A

  By the way, when a pattern is formed by the conventional inkjet method, the ink is directly applied to the polyvinyl alcohol film as a support from the relationship of the viscosity, surface tension, solid content concentration, drying speed, etc. of the ink used in the inkjet method. It is difficult to form a pattern by landing. For this reason, it is common to form an ink absorbing layer for absorbing the ink solvent on the polyvinyl alcohol film.

  Since the ink absorbing layer needs to be formed on a polyvinyl alcohol film, it is necessary to use a non-aqueous solvent that does not dissolve the polyvinyl alcohol film. The ink-absorbing layer is formed by applying this non-aqueous solvent to the polyvinyl alcohol film and then drying it. Then, an arbitrary pattern is drawn using an inkjet ink made of an ink solvent suitable for the ink absorbing layer and dispersed with various colored pigments, and a hydraulic transfer film with the pattern is obtained.

  The inventors of the present application conducted a transfer study using a hydraulic transfer film that was inkjet printed on the ink absorbing layer on the polyvinyl alcohol film. As a result, the hydraulic transfer film obtained by inkjet printing was created by conventional gravure printing. It was clarified that the film showed different behavior from the film.

  Specifically, in inkjet printing, it is possible to arbitrarily create a portion on which a pattern is printed and a portion on which a pattern is not printed. So do not draw a picture. When the printed part and the non-printed part are separated as a large area, the inventors have different stretchability of the part in the transfer process, and as a result, a good transfer product is stabilized. I found it impossible to make.

  Accordingly, an object of the present invention is to provide an ink-jet-printed hydraulic transfer film in which transfer failure such as pattern bending is unlikely to occur in a transfer process which is a subsequent process.

In order to solve the above problems, the hydraulic transfer film of the present invention is
A support sheet made of a water-soluble or water-swellable resin;
An ink absorbing layer that is coated on one side of the support sheet and absorbs the solvent of the solvent-based inkjet ink;
An ink layer formed by absorbing the ink-jet ink in the ink absorption layer,
The ink layer is
A first region corresponding to a pattern to be transferred to the transfer object;
And a second region having a density lower than that of the first region, which is a region that is not transferred to the transfer object.

  In the hydraulic transfer film of one embodiment, the first region is surrounded by the second region.

Moreover, in the hydraulic transfer film of one embodiment,
The support sheet is formed in a band shape,
Each of the first region and the second region extends in the longitudinal direction of the support sheet,
The first region and the second region are adjacent to each other in the width direction of the support sheet.

Moreover, in the hydraulic transfer film of one embodiment,
The ink absorbing layer is made of an isocyanate crosslinked acrylic resin,
The inkjet ink uses a mixed solvent of glycol ester and glycol ether as a main solvent.

  According to the hydraulic transfer film of the present invention, the ink layer includes a first area corresponding to a pattern for transferring to the transfer object, an area not transferred to the transfer object, and the first area. And the second region having a density lower than the density of the image, so that transfer defects such as pattern bending are less likely to occur in the transfer process.

It is a schematic block diagram which shows the hydraulic transfer film of 1st Embodiment of this invention. It is a conceptual diagram which performs inkjet printing on the unprinted raw | natural pressure transfer film. It is a schematic diagram of the hydraulic transfer film after inkjet printing. It is a figure which shows the relationship between a resin cabinet and a hydraulic transfer film. It is a figure which shows the transfer process using a hydraulic transfer film. It is a figure which shows the relationship between a resin cabinet and the conventional hydraulic transfer film. It is a schematic diagram which shows the hydraulic transfer film of 2nd Embodiment of this invention. It is a schematic diagram which shows the conventional hydraulic transfer film.

  Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments.

(First embodiment)
FIG. 1 is a schematic configuration diagram showing a hydraulic transfer film according to a first embodiment of the present invention. As shown in FIG. 1, the hydraulic transfer film 1 includes a support sheet 10, an ink absorption layer 20 coated on one side of the support sheet 10, and an ink layer 30 formed on the ink absorption layer 20. Is provided.

  The support sheet 10 may be a sheet having water solubility or water swellability. For example, a resin such as polyvinyl alcohol, polyvinyl pyrrolidone, dextrin, gelatin, glue, sodium alginate, hydroxyethyl cellulose, acetylbutyl cellulose or the like is used as a sheet. What was formed in is used. As thickness of the support body sheet 10, 10-100 micrometers is preferable. In the present embodiment, a sheet made of polyvinyl alcohol resin having a thickness of 30 μm is used.

  The ink absorbing layer 20 is formed by applying a coating solution obtained by dissolving an acrylic resin in a non-aqueous solvent on the support sheet 10 and evaporating the non-aqueous solvent. Examples of the acrylic resin used in the ink absorbing layer 20 include poly (meth) acrylate methyl, poly (meth) butyl acrylate, methyl (meth) acrylate-butyl (meth) acrylate copolymer, (meth). One kind alone or a mixture of two or more kinds such as methyl acrylate- (meth) acrylate 2-hydroxyethyl copolymer is used. In this embodiment, a copolymer of butyl acrylate and methyl (meth) acrylate is used.

  Non-aqueous solvents for dissolving acrylic resins include monohydric alcohols such as methyl alcohol, ethyl alcohol, propyl alcohol, and butyl alcohol, polyhydric alcohols such as ethylene glycol, propylene glycol, and glycerin, acetone, methyl ethyl ketone, and methyl isobutyl. Ketones, ketones such as cyclohexanone, ethyl ether, isopropyl ether, ethylene glycol mono-methyl ether, ethylene glycol mono-ethyl ether, ethylene glycol mono-butyl ether, diethylene glycol mono-methyl ether, diethylene glycol mono-ethyl ether , Ethers such as diethylene glycol mono-butyl ether, ethyl acetate, butyl acetate, ethylene glycol mono-ethyl ether Acetate, ethylene acetate, mono, butyl ether, acetate, diethylene glycol, mono, methyl ether, acetate, diethylene glycol, mono, ethyl ether, acetate, diethylene glycol, mono, butyl ether, acetate, pentane, hexane, heptane, Aromatic hydrocarbons such as octane, benzene, toluene, xylene, cyclohexane, and ethylbenzene are used alone or as a mixed solvent. In this embodiment, ethyl acetate is used as the main component (main solvent) of the non-aqueous solvent.

  As a result of our study, the support sheet 10 is preferably water-soluble polyvinyl alcohol in terms of transfer stability. And as a resin component, it is 2-7 micrometers thickness with respect to the water-soluble polyvinyl alcohol surface by using the coating liquid which used the copolymer of butyl acrylate and methyl (meth) acrylate as a solvent. Even a thin layer coating of this type was suitable because stable coating was possible.

  In addition, as a method of applying a coating solution obtained by dissolving an acrylic resin in a non-aqueous solvent on the support sheet 10, coating means such as gravure coating, roll coating, die coating, and bar coating can be used. The body sheet 10 is generally packaged in a roll shape, and a treatment method called roll-to-roll is preferable, and coating means such as gravure coating, roll coating, and die coating are preferable.

  The ink absorbing layer 20 used for other purposes generally has a thickness of 10 to 30 μm. However, in the hydraulic transfer film, the thickness of the ink absorbing layer 20 is 2 in order to achieve both printability and transferability. It is desirable that it is ˜7 μm. If it is 2 μm or less, if the amount of ink is large, the ink absorption layer 20 is cracked over the entire thickness and the transfer quality is deteriorated. On the other hand, if it is 7 μm or more, there is a high possibility of wrinkling during transfer. In order to further reduce the generation of wrinkles during transfer, the thickness of the ink absorbing layer 20 is desirably in the range of 2 to 5 μm.

  In addition, after coating the coating liquid on the support sheet 10, the ink absorbing layer 20 is formed by being heated and dried by a drying means such as an oven. In the transfer step, it is preferable that the heating temperature is 40 to 80 ° C. and the heating time is 1 to 10 minutes so that the time for softening, dissolution and swelling after landing does not change. In this embodiment, it is dried by heating in an oven at 80 ° C. for 1 minute.

  From the viewpoint of printability, a weight average molecular weight of 50,000 or more is preferable, and a weight average molecular weight of 100,000 or more, which reduces the landing diameter in order to increase the resolution of the ink layer 30, is more preferable. Coating becomes difficult. For this reason, when handling is considered, a weight average molecular weight of 500,000 or less that gives a viscosity of 1 Pa · s or less is more preferable.

<Inkjet ink>
The composition of the non-aqueous inkjet ink according to the present invention includes at least components of a pigment, a dispersant for dispersing the pigment, a resin, and a solvent. Hereinafter, each component will be described.

(Pigment)
The pigment used in the composition of the non-aqueous inkjet ink is not particularly limited, and an inorganic pigment or an organic pigment can be appropriately selected.

  Inorganic pigments include carbon black, titanium oxide, zinc oxide, iron oxide, kaolinite, barium sulfate, calcium carbonate, silica, alumina, brown, chrome vermilion, chrome lead, chrome yellow, cadmium yellow, titanium yellow, and chrome oxide. , Cobalt green, cobalt blue, ultramarine, and bitumen.

  Organic pigments include monoazo pigments, diazo pigments, diazo condensation pigments, azomethine pigments and other azo pigments, isoindolinone pigments, isoindoline pigments, quinophthalone pigments, anthraquinone pigments, quinacridone pigments, imidazolone pigments, benzimidazolone pigments, and perinone pigments. Perylene pigments, indigo pigments, thioindigo pigments, oxazine pigments, dioxazine pigments, polycyclic pigments such as phthalocyanine pigments, and the like.

  Specifically, for example, Pigment Yellow 1, 3, 12, 13, 14, 17, 34, 35, 37, 42, 53, 65, 74, 81, 83, 93, 94, 95, 110, 111, 128 129, 138, 150, 151, 153, 154, 155, 157, 175, 180, Pigment Blue 15, 15: 1, 15: 3, 15: 4, 15: 6, 17: 1, 27, 29, 60 Pigment Green 7, 36, Pigment Red 5, 17, 22, 48: 1, 48: 2, 48: 3, 48: 4, 49: 1, 53: 1, 57: 1, 101, 112, 122, 146 177, 178, 179, 185, 202, 254, 255, Pigment Violet, 19, 23, 50, Pigment Orange 13, 16, Pigment Black 7, Pigment White , And the like 18 and 21. These pigments can be used alone or in combination of two or more.

  The average primary particle diameter of the pigment after the dispersion treatment is preferably 50 to 200 nm, more preferably 60 to 150 nm in consideration of dispersibility and dischargeability. When the average primary particle diameter of the pigment is smaller than the above range, the cohesiveness increases or the color developability deteriorates. On the other hand, if it is larger than the above range, nozzle clogging is likely to occur, and the discharge performance becomes unstable.

  The blending amount in the ink composition is preferably 1 to 15% by weight, and more preferably 2 to 10% by weight. When the amount of the pigment is less than the above range, the color developability deteriorates and only a light color can be expressed. Conversely, when it exceeds the above range, the viscosity stability of the ink composition itself deteriorates, and the ink quality is sufficiently maintained. It ’s gone.

  In order to effectively disperse these pigments in an organic solvent effectively with a pigment dispersant, it is better to have reactive functional groups (hydroxyl group, carboxy group, sulfonic acid group, etc.) on the surface of the pigment. The interaction with the pigment dispersant is preferably increased. Even if there is no reactive functional group, the reactive functional group can be introduced by performing surface treatment such as oxygen plasma treatment or UV irradiation treatment.

(Pigment dispersant)
As the pigment dispersant used in the composition of the non-aqueous inkjet ink, an ionic surfactant, an anionic or cationic polymer compound, or the like can be used. In particular, a polymer compound in which a basic functional group is contained in a molecular chain is preferable because it has a good adsorptivity on a pigment surface in an organic solvent and provides a stable dispersion effect.

  Specifically, as commercial products, Disperbyk-161, 162, 163, 166, 182, 183, 184, 185, 2000, 2050, 2150, manufactured by BYK Chemie, Ajinomoto Fine Techno Co., Ltd., Ajisper PB-821, 822, 881, Dispalon DA-703-50 manufactured by Enomoto Kasei Co., Ltd., and the like.

  The pigment dispersant must be appropriately selected according to the type of pigment and the type of organic solvent to be used. The blending amount of the pigment dispersant in the ink composition is preferably 10 to 100% by weight, more preferably 15 to 80% by weight with respect to the organic pigment, and preferably 0.5 to It is added at 8% by weight, more preferably 1 to 5% by weight. If it is smaller than the above range, the desired dispersion performance is not exhibited and the cohesiveness becomes high. On the other hand, if it is larger than the above range, the viscosity becomes high, resulting in unstable ejection properties or nozzle clogging.

(Binder resin)
The resin contained in the composition of the non-aqueous inkjet ink used in the present invention is to satisfy both the constraint conditions required from the viewpoint of inkjet ejection properties and the constraint conditions required from the viewpoint of drawability on the hydraulic transfer film 1. Is essential.

  With respect to the ejection performance, first, it must be in a viscosity range suitable for ejection corresponding to the ink jet apparatus, with little variation in ejection state and high stability over time. For this purpose, it is desirable that the resin has a molecular weight that is not too high and that has little variation in molecular structure and degree of polymerization.

  Regarding the drawability, in order to improve the followability of the landing shape with respect to the extension behavior of the flexible ink absorbing layer 20, it is important that the resin does not have a too high molecular weight and has a high degree of freedom in molecular design. .

  In the case where an acrylic resin excellent in structural design is targeted as the flexible ink absorbing layer 20, an acrylic resin is most suitable as the resin used in the present invention in consideration of the necessity of molecular design of the ink composition. .

The acrylic resin can be obtained by copolymerizing a single monomer or a plurality of monomers by known radical polymerization. Examples of the monomer include acrylic acid esters such as methyl acrylate, ethyl acrylate, isopropyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, butyl methacrylate, methacrylic acid. And methacrylic acid esters such as isobutyl acid, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, and stearyl methacrylate.

  In addition, monomers having a functional group can also be used, for example, carboxyl group-containing monomers such as acrylic acid, methacrylic acid, maleic acid, and fumaric acid, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, and the like. Hydroxyl group-containing acrylic acid ester, hydroxyl group-containing methacrylate ester such as 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, amide group-containing monomers such as acrylamide, methacrylamide, maleic acid amide, and fumaric acid amide, methacrylic acid And tertiary amino group-containing monomers such as dimethylaminoethyl and diethylaminoethyl methacrylate. These monomers may be used alone or in combination of two or more.

  The weight average molecular weight of the acrylic resin contained in the inkjet ink composition used in the present invention is preferably in the range of 5000 to 20000, and more preferably in the range of 7000 to 15000. When the weight average molecular weight of the acrylic resin contained in the inkjet ink composition is smaller than this range, the inkjet ink has no film forming property, color fixing property, and glossiness. Conversely, when the weight average molecular weight of the acrylic resin contained in the ink-jet ink composition is larger than the above range, nozzle clogging is likely to occur, and ejection properties become unstable.

  The weight average molecular weight of the ink binder resin is preferably lower than the weight average molecular weight of the acrylic resin of the ink absorbing layer 20. In the transfer step, the ink layer 30 and the ink absorption layer 20 of the hydraulic transfer film 1 are softened by coating with an activator made of an organic solvent. However, when the weight average molecular weight of the binder resin of the ink layer 30 is higher than the weight average molecular weight of the acrylic resin of the ink absorbing layer 20, not only the portion of the ink layer 30 is not easily softened by the activator, but the ink layer Since the active agent is prevented from uniformly penetrating into the ink absorbing layer 20 located below 30, the difference in flexibility (attachment at the time of transfer) increases from place to place due to the difference in pattern density. It is. The organic solvent can be appropriately selected depending on the characteristics of the hydraulic transfer film.

  The blending amount of the acrylic resin in the inkjet ink composition is preferably in the range of 2 to 8% by weight. When the blending amount of the acrylic resin is less than this range, there is a problem that the shape retention after landing on the ink absorbing layer 20 is weak or the fixability of the pigment is deteriorated. The viscosity of the inkjet ink composition is increased, and the ejection stability of the inkjet is deteriorated.

  In addition to the acrylic resin, a small amount of ester resin, urethane resin, rosin resin, alkyd resin, styrene-acrylic resin, cellulosic resin, etc. is added within the range where the discharge performance and drawing performance do not deteriorate. Thus, it is also possible to supplement characteristics such as the landing shape and color developability.

(Organic solvent)
As the main solvent of the organic solvent contained in the non-aqueous ink jet ink composition of the present invention, glycol ester solvents and glycol ether solvents are used. The glycol ester solvent and glycol ether solvent can dissolve the pigment, the dispersant for dispersing the pigment, and the acrylic resin, and can provide solution characteristics suitable for inkjet discharge.

  Examples of glycol ester solvents include ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol mono-n-butyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol mono-n-butyl ether acetate, propylene glycol monomethyl ether acetate. And dipropylene glycol monomethyl ether acetate. Since the solvent of the glycol ester solvent has good resin solubility, even an acrylic resin having a high molecular weight can be easily dissolved and dispersed uniformly, and the application range of the acrylic resin is expanded.

  Further, the glycol ester solvent is not only absorbed by the ink absorbing layer 20 described above, but also has an effect of improving the adhesion between the binder resin in the ink and the ink absorbing layer 20 by dissolving a part of the surface layer. Therefore, it is preferred that the solvent contains a glycol ester solvent. Among these, diethylene glycol mono-n-butyl ether acetate and propylene glycol monomethyl ether acetate are preferable because they can stably disperse the binder resin and have high adhesion effect with the ink absorption layer 20.

  Glycol ether solvents are often used as solvents for inkjet inks. This is because there are multiple solvents with different boiling points related to problems such as clogging of inkjet nozzles due to drying and viscosities that are indicators for stably discharging fine droplets from the inkjet head, and their mixing properties are good, This is because a plurality of glycol ether solvents are often mixed and blended in a form that matches the characteristics of the inkjet head and the usage environment.

  Examples of the low-boiling glycol ether solvent that can contribute to the reduction in the viscosity of the entire inkjet ink composition include ethylene glycol monomethyl ether (124 ° C.), ethylene glycol monoethyl ether (135 ° C.), and ethylene glycol mono Isopropyl ether (144 ° C), ethylene glycol mono-n-propyl ether (152 ° C), ethylene glycol mono-n-butyl ether (171 ° C), propylene glycol monomethyl ether (121 ° C), propylene glycol monoethyl ether (133 ° C) Propylene glycol mono-n-propyl ether (150 ° C.), propylene glycol mono-n-butyl ether (170 ° C.), dipropylene glycol dimethyl ether (171 ° C.), etc. It is under (Figures in parentheses after the solvent name indicates the boiling point). Of these, propylene glycol monomethyl ether and propylene glycol mono-n-butyl ether are preferable.

  Examples of the glycol ether solvent that has a high boiling point and can slow down the drying property that causes nozzle clogging include diethylene glycol monomethyl ether (194 ° C.), diethylene glycol monoethyl ether (202 ° C.), diethylene glycol diethyl ether (189 ° C.), Diethylene glycol mono-n-butyl ether (230 ° C.), diethylene glycol butyl methyl ether (212 ° C.), diethylene glycol dibutyl ether (256 ° C.), triethylene glycol monomethyl ether (249 ° C.), triethylene glycol dimethyl ether (216 ° C.), triethylene glycol Monoethyl ether (256 ° C.), dipropylene glycol monomethyl ether (189 ° C.), dipropylene glycol-n-propyl Ether (212 ° C.), dipropylene glycol-n-butyl ether (229 ° C.), tripropylene glycol monomethyl ether (242 ° C.), tripropylene glycol dimethyl ether (215 ° C.), etc. Shows boiling point). Especially, when the ink absorption layer 20 is an acrylic resin, diethylene glycol monoethyl ether and diethylene glycol mono-n-butyl ether are preferable in terms of permeability to the ink absorption layer 20.

  In the present invention, by using such a glycol ether solvent alone or in combination, the ink for ink jet sufficiently penetrates into the ink absorbing layer 20 and damages the ink absorbing layer 20 by dissolution. There is no. Therefore, the ink for ink jet and the ink absorbing layer 20 are compatible with each other, and even a thin absorbing layer does not easily cause cracking or bleeding, and can stably achieve both printability and transferability. Ink-jet ink suitable for the above can be prepared.

(Ink manufacturing method)
The non-aqueous ink jet ink composition of the present invention stirs and disperses the above-described material components using a dispersing machine such as a bead mill, a ball mill, a sand mill, an attritor, or a roll mill so that the viscosity becomes 3 to 10 mPa · s. It can be obtained by adjusting to The stirred and dispersed ink composition is filtered through a filter such as a membrane filter or a cartridge filter, and large particles are removed to obtain a target non-aqueous ink jet ink composition.

  Next, a method for performing inkjet printing on an unprinted raw hydraulic transfer film using the non-aqueous inkjet ink composition will be described. Ink jet printing is formed by ejecting fine droplets of an ink composition by an ink jet device and landing on the ink absorbing layer. As the ink jet device, various ink jet driving methods such as an electrostatic suction type, a piezoelectric method, and a bubble jet method can be adopted.

  FIG. 2 is a conceptual diagram in which inkjet printing is performed on an unprinted raw hydraulic transfer film. In this embodiment, an unprinted roll of raw water pressure transfer film 11 formed by the support sheet 10 and the ink absorbing layer 20 is rolled using a commercially available roll paper printer (for example, JV33 manufactured by Mimaki Engineering Co., Ltd.). Print. The unprinted raw water pressure transfer film 11 is first mounted on the unwinding roller 40, and is wound around the winding roller 42 via the intermediate roller 41. Between the unwinding roller 40 and the intermediate roller 41, ink droplets 51 of four colors of black, blue, red, and yellow are drawn according to image data from an inkjet head 50 that is previously mounted on the printer, and the raw water pressure It lands on the ink absorbing layer 20 side of the transfer film 11 and is colored. After passing through the intermediate roller 41 and before being sequentially taken up by the take-up roller 42, hot air 61 at 40 to 50 ° C. is applied to the ink absorbing layer 20 side by the hot air generator 60, and the ink droplets 51 are dried. The

  FIG. 3 is a schematic diagram of a hydraulic transfer film 1 that has been inkjet printed. As shown in FIG. 3, the roll-shaped hydraulic transfer film 1 is printed with a pattern 31 to be transferred to the transfer object and a frame print 32 representing a relative positional relationship with the pattern 31. . In addition, thin printing 33 is performed in an area that is not transferred to the transfer object.

  In other words, the ink layer 30 of the hydraulic transfer film 1 has a pattern 31 as a first area and a thin print 33 as a second area having a density lower than the density of the pattern 31. The pattern 31 is surrounded by a thin print 33 in an island shape.

  FIG. 4 is a diagram showing a relationship between a resin cabinet 80 as a transfer object and an ink-jet printed hydraulic transfer film 1. FIG. 4A shows a cross-sectional view, and FIG. 4B shows a plan view. As shown in FIG. 4, the hydraulic transfer film 1 is printed with a pattern 31 that is slightly larger than the resin cabinet 80 and transferred to the resin cabinet 80. A thin print 33 is printed in an area other than the picture 31. A frame print (not shown) is printed around the thin print 33.

  To obtain the hydraulic transfer film 1 shown in FIG. 4, the inkjet-printed roll-shaped hydraulic transfer film 1 shown in FIG. 3 is unwound, and a masking tape (outer shape regulation tape) made of Japanese paper along the inside of the frame print 32. The hydraulic transfer film 1 to which the outer shape regulating tape 70 is stuck is obtained by pasting 70 on the four sides and cutting with a cutter knife along the frame printing 32.

  FIG. 5 is a diagram showing a transfer process using the hydraulic transfer film 1 to which the outer shape regulating tape 70 is stuck. As shown in FIG. 5A, after the hydraulic transfer film 1 is floated on the water surface 100 with the pattern 31 facing upward, the hydraulic transfer film 1 made of an organic solvent is scanned while scanning the general-purpose coating gun 110 in the direction of arrow A. An appropriate amount of the activator 111 for softening is applied from the general-purpose paint gun 110 onto the hydraulic transfer film 1.

  After the activator 111 is applied, as shown in FIG. 5 (b), the positioning plate 120 in the X direction (left and right direction in the figure) and Y direction (in the depth direction in the figure) that is installed in advance in the transfer water tank that performs transfer is used. Then, the hydraulic transfer film 1 is pressed in the direction of arrow B by a film slide mechanism (not shown), and positioning is performed so that the hydraulic transfer film 1 comes to a predetermined position in the transfer water tank. In FIG. 5B, the hydraulic transfer film 1 is slid in the left-right direction, but the same processing is performed in the depth direction.

  Then, as shown in FIG. 5C, the resin cabinet 80 is slid in the direction of arrow C by a slide mechanism (not shown) whose movement position is determined with respect to the transfer water tank, so that the resin cabinet 80 is moved to the hydraulic transfer film. 1 is pressed against the pattern 31 to complete the transfer of the pattern 31 to the resin cabinet 80.

  Thereafter, the water-soluble support sheet 10 remaining on the surface is washed away with water, dried in an oven, and then a general-purpose top coat is applied to complete a decorative transfer product.

  Here, as a comparative example, a conventional hydraulic transfer film 150 will be described. FIG. 6 is a view showing the relationship between a resin cabinet 80 as a transfer object and a conventional hydraulic transfer film 150. 6A shows a cross-sectional view, FIG. 6B shows a plan view, and FIG. 6C shows an operation explanatory diagram.

  As shown in FIGS. 6 (a) and 6 (b), the conventional hydraulic transfer film 150 does not print the region other than the pattern 31. That is, the conventional hydraulic transfer film 150 does not have the thin print 33 of the hydraulic transfer film 1 of the present invention. Then, when an activator is applied to the conventional hydraulic transfer film 150, as shown in FIG. 6C, the area on which the pattern 31 is printed preferentially extends, and the pattern 31 is distorted. This has been clarified by the inventors' investigation.

  Therefore, it has been found that such a problem can be improved by thinly printing the area other than the pattern 31 as in the present invention.

  In a hydraulic transfer film manufactured using a conventional gravure printing method, only a continuous pattern can be printed over the entire roll film, and it is impossible to print a pattern only on the portion where the transfer object contacts. . When a hydraulic transfer film is produced by an inkjet printing method as in the present invention, it is possible for the first time to print a picture only on a necessary portion, and these problems have become apparent and have led to the present invention.

  The reason why the ink jet printed region is more likely to be stretched when the activator is applied is that a small crack is generated on the surface in the process of ink soaking into the ink absorbing layer 20, and the elongation is promoted starting from this crack. This is a phenomenon caused by the configuration in which the ink absorbing layer 20 is provided. Since the micro cracks generated only on the surface are generated even if the amount of ink droplets is small, they are generated even in thin printing. That is, for the thin print 33, it is effective even if the density is low, and it is desirable to print at a density lower than that of the pattern 31 in terms of suppressing unnecessary ink consumption, and it is a solid print consisting of a plurality of ink colors. More desirable. In particular, this effect was remarkable when the ink absorbing layer 20 subjected to isocyanate crosslinking was used.

  In addition, in the hydraulic transfer film 1 in which the ink absorbing layer 20 is uniformly coated on one surface of the support sheet 10, the outer shape can be maintained simply by applying the masking tape 70 to the outer periphery. By doing so, the transferred object can be positioned and transferred. A conventional hydraulic transfer film without an ink absorbing layer is unsuitable because the outer shape regulating tape is bent outward.

  That is, the ink layer 30 of the hydraulic transfer film 1 has a pattern 31 (first area) for transferring to the transfer object, and an area that is not transferred to the transfer object and has a density lower than the density of the pattern 31 Therefore, the distortion of the pattern 31 is reduced, and accurate positioning transfer is also possible.

  The picture 31 is surrounded by the thin print 33. Thereby, in the hydraulic transfer decoration using a sheet-fed film, decoration with little pattern distortion is possible.

The hydraulic transfer film 1 of the present invention is
A support sheet 10 made of a water-soluble or water-swellable resin;
An ink absorbing layer 20 that is coated on one side of the support sheet 10 and absorbs the solvent of the solvent-based inkjet ink;
An ink layer 30 formed by absorbing the ink-jet ink in the ink absorption layer 20;
The ink layer 30 is
A first region 31 corresponding to a pattern to be transferred to the transfer object 80;
The second region 33 is a region that is not transferred to the transfer target 80 and has a density lower than that of the first region 31.

  According to the hydraulic transfer film 1 of the present invention, the ink layer 30 is a first area 31 corresponding to a pattern to be transferred to the transfer object 80, an area that is not transferred to the transfer object 80, and And a second region 33 having a density lower than that of the first region 31.

  Thereby, in the process of transferring the design of the hydraulic transfer film 1 to the transfer object 80, when the support sheet 10 is dissolved and the ink absorbing layer 20 is softened, the extension of the first region 31 and the second region The difference from the elongation of the region 33 can be reduced.

  Therefore, distortion of the first area 31 (picture) can be reduced, and a desired picture can be transferred to a predetermined position of the transfer object 80.

  The first region 31 is surrounded by the second region 33.

  Therefore, in the hydraulic transfer decoration using a single-wafer type film, decoration with little pattern distortion is possible.

(Second Embodiment)
FIG. 7 is a schematic view showing a hydraulic transfer film according to a second embodiment of the present invention. The second embodiment differs from the first embodiment only in the relative positions of the pattern and the thin print. Only this different configuration will be described below. In the second embodiment, the same reference numerals as those in the first embodiment are the same as those in the first embodiment, and the description thereof is omitted.

  As shown to Fig.7 (a), according to the hydraulic transfer film 1A of this embodiment, the support body sheet | seat 10 is formed in strip | belt shape. The pattern (first region) 34 and the thin print 35 (second region) each extend in the longitudinal direction of the support sheet 10. The pattern 34 and the thin print 35 are adjacent to each other in the width direction of the support sheet 10. That is, the thin print 35, the picture 34, and the thin print 35 are arranged in order along the width direction of the support sheet 10.

  Then, a roll-shaped water pressure transfer film 1A is prepared, and an activator is applied on the water surface while the water pressure transfer film 1A is continuously immersed in a transfer water tank. As shown in FIG. The pattern 34 is transferred to the resin cabinet 80 by sequentially contacting the pattern 34 of the hydraulic transfer film 1A.

  Therefore, in the hydraulic transfer film 1A continuously printed in a roll shape, it is possible to stabilize the extensibility in the roll width direction after landing, and to reduce the distortion of the pattern 34. That is, when it is not necessary to position and transfer the pattern 34, it is possible to increase productivity while reducing distortion of the pattern 34.

  Note that the thin print 35 is effective even if the density is low, and it is desirable to print at a density lower than that of the pattern 34 in terms of suppressing unnecessary ink consumption. In particular, this effect was remarkable when the ink absorbing layer 20 subjected to isocyanate crosslinking was used.

  Here, as a comparative example, a conventional hydraulic transfer film 150A will be described. When there is no thin print 35 in an area other than the pattern 34, as shown in FIG. 8, the pattern 34 preferentially extends, and the amount of elongation is not constant, and the pattern 34 is distorted due to nonuniformity. End up.

In the hydraulic transfer film 1A of this embodiment,
The support sheet 10 is formed in a band shape,
The first region (picture) 34 and the second region (thin printing) 35 respectively extend in the longitudinal direction of the support sheet 10.
The first region 34 and the second region 35 are adjacent to each other in the width direction of the support sheet 10.

  Therefore, in the hydraulic transfer film 1A continuously printed in a roll shape, it is possible to stabilize the extensibility in the roll width direction after landing, and to reduce the picture distortion. In other words, when it is not necessary to position and transfer the pattern, it is possible to increase productivity while reducing pattern distortion.

(Third embodiment)
Next, the hydraulic transfer film of 3rd Embodiment of this invention is demonstrated. In the third embodiment, a small amount (˜1%) of an isocyanate solution diluted with an ethyl acetate solvent is added to a coating solution using the above-described acrylic resin as a resin component and ethyl acetate as a solvent, and then water-soluble. By coating and drying on the surface of polyvinyl alcohol, it is possible to obtain a hydraulic transfer film that further combines printability and flexibility in the transfer process.

  By adding the isocyanate solution, the ink absorbing layer can partially form a three-dimensional network structure by the isocyanate group. The optimum addition amount of the isocyanate solution varies depending on the acrylic resin component and the activator component described later, but it is desirable to add an amount of the isocyanate solution derived from experiments in order to further improve the printability and transferability.

  That is, by using an isocyanate-crosslinked acrylic resin as an ink absorption layer, the first region as a pattern for transferring to an object to be transferred and the region other than the first region are thinner than the first region. The uniformity of elongation at the time of transfer between the second region being printed is increased, and more stable transfer is possible.

  As a comparative experiment, a coating liquid made of an ethyl acetate solvent was prototyped and studied using a commonly used polyurethane resin as a material for the ink absorbing layer. Although the molded product tries to stretch when pressed against the film, it tries to return to its original shape due to its elastic force. As a result, the film is transferred with wrinkles, which is inappropriate.

  In addition, as another comparative experiment, when an isocyanate solution is not added to a coating liquid made of an acrylic resin, in ink jet printing using an ink made of a mixed solvent of glycol ester and glycol ether, an ink absorbing layer is formed due to light and shade of a pattern. The difference in the degree of cracks to be generated becomes large, and it is necessary to suppress the distortion of the pattern by adjusting the amount of the activator for each pattern.

In the hydraulic transfer film of this embodiment,
The ink absorbing layer is made of an isocyanate crosslinked acrylic resin,
The inkjet ink uses a mixed solvent of glycol ester and glycol ether as a main solvent.

  Therefore, the uniformity of elongation at the time of transfer between the first area (picture) and the second area (thin printing) is increased, and more stable transfer is possible.

  In addition, this invention is not limited to the above-mentioned embodiment, A design change is possible in the range which does not deviate from the summary of this invention.

1, 1A Hydraulic transfer film 10 Support sheet 20 Ink absorbing layer 30 Ink layer 31 Picture (first region)
32 Frame printing 33 Thin printing (second area)
34 Design (first area)
35 Thin print (second area)
70 Masking tape 80 Resin cabinet (transferred material)

Claims (4)

A support sheet made of a water-soluble or water-swellable resin;
An ink absorbing layer that is coated on one side of the support sheet and absorbs the solvent of the solvent-based inkjet ink;
An ink layer formed by absorbing the ink-jet ink in the ink absorption layer,
The ink layer is
A first region corresponding to a pattern to be transferred to the transfer object;
A hydraulic transfer film comprising: a second region that is a region that is not transferred to the transfer object and has a density lower than that of the first region. In the hydraulic transfer film according to claim 1,
The hydraulic transfer film, wherein the first region is surrounded by the second region. In the hydraulic transfer film according to claim 1,
The support sheet is formed in a band shape,
Each of the first region and the second region extends in the longitudinal direction of the support sheet,
The hydraulic transfer film, wherein the first region and the second region are adjacent to each other in the width direction of the support sheet. In the hydraulic transfer film according to any one of claims 1 to 3,
The ink absorbing layer is made of an isocyanate crosslinked acrylic resin,
The hydraulic transfer film, wherein the inkjet ink uses a mixed solvent of glycol ester and glycol ether as a main solvent.

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