JP2014019000A - Hydraulic transfer film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydraulic transfer film capable of high-definition printing and improving ultraviolet resistance while maintaining quality of a transfer object by using an ink jet method.SOLUTION: A hydraulic transfer film 1 comprises a support medium film 10, an ink absorption layer 20, and a pattern layer 30. One side of the support medium film 10 is coated with the ink absorption layer 20. The pattern layer 30 is printed on the ink absorption layer 20 that includes an acrylic resin-based ink receptive resin 21, and a benzotriazole ultraviolet absorber 22 provided in the ink receptive resin 21 that absorbs a solvent in an inkjet ink. The ultraviolet absorber 22 absorbs ultraviolet rays. A solid weight ratio of the ultraviolet absorber 22 to the ink receptive resin 21 is 3 to 10%.

Description

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

  The hydraulic transfer method is known as a technique that can impart a design layer rich in design to a molded product having a three-dimensional surface or a curved surface with unevenness (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 pattern layer is formed on a water-soluble or water-swellable film such as a polyvinyl alcohol film as a support by a printing means such as gravure printing. Was adopted.

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

  However, when printing a pattern by the inkjet method, the inkjet ink needs to have a viscosity as small as about 2 to 20 cp, and furthermore, in order to stably disperse a color pigment having a large specific gravity with respect to the ink solvent. In addition, a small color pigment on the order of submicron is dispersed in the ink solvent. For this reason, there has been a problem that the ultraviolet resistance is weaker than that of the conventional pigment for gravure printing.

  In order to solve these problems, Japanese Unexamined Patent Application Publication No. 2009-214420 (Patent Document 3) discloses that an additive such as an ultraviolet absorber is introduced into the transparent image-receiving layer of the hydraulic transfer sheet.

Japanese Patent No. 2757346 Japanese Patent No. 3952748 JP 2009-214420 A

  By the way, the inventors of the present application have studied for the purpose of improving the ultraviolet resistance of a hydraulic transfer film used for inkjet printing. As a result, the UV resistance can be improved by adding an ultraviolet absorber in the image-receiving layer of the hydraulic transfer film, but it is suitable for the addition amount of the ultraviolet absorber, the inkjet printing process, and the hydraulic transfer process. Otherwise, it was found that the desired picture transfer was not obtained.

  That is, Patent Document 3 suggests that an additive be added to the image-receiving layer of the hydraulic transfer film, but does not suggest a hydraulic transfer film from which a high-quality transfer product can be obtained.

  Accordingly, an object of the present invention is to provide a hydraulic transfer film that enables high-definition printing by an ink jet method and improves the ultraviolet resistance while maintaining the quality of the transferred material.

In order to solve the above problems, the hydraulic transfer film of the present invention is
A support film made of a water-soluble or water-swellable resin;
An ink absorbing layer coated on one side of the support film,
The ink absorbing layer is
An acrylic resin-based ink-receiving resin that absorbs the solvent of the inkjet ink;
A benzotriazole-based UV absorber provided in the ink-receiving resin;
The solid weight ratio of the ultraviolet absorber to the ink-receiving resin is 3 to 10%.

  According to the hydraulic transfer film of the present invention, since the solid weight ratio of the ultraviolet absorber to the ink receiving resin is 3 to 10%, the ink absorbing layer capable of high-definition ink jet printing has ultraviolet resistance. It becomes possible to grant. Therefore, it is possible to improve the UV resistance while maintaining the quality of the transferred material.

In one embodiment of the hydraulic transfer film,
The ink receptive resin is an acrylic resin-based isocyanate cross-linked product obtained by solidifying a coating liquid composed of an ethyl acetate solvent.
The ultraviolet absorber is 2- (2′-hydroxy-5′-t-octylphenyl) benzotriazole or 2- (5-methyl-2-hydroxyphenyl) benzotriazole.

  According to the hydraulic transfer film of this embodiment, by using an ethyl acetate solvent, an acrylic resin-based isocyanate crosslinked product that enables high-definition printing, and 2- (2′-hydroxy-5′-t-octyl) Affinity with phenyl) benzotriazole or 2- (5-methyl-2-hydroxyphenyl) benzotriazole is improved. Thereby, since a soluble state can be maintained even at high concentration addition, stable characteristics can be obtained.

In one embodiment of the hydraulic transfer film,
Provided with a pattern layer printed by inkjet ink on the ink absorption layer,
The ink receptive resin is semi-dissolved by the adhesive and can be fixed on the surface of the transfer object.
The ultraviolet absorber is soluble in the main solvent of the inkjet ink and the main solvent of the adhesive.

  According to the hydraulic transfer film of this embodiment, the ink receptive resin swells with the inkjet ink and becomes semi-dissolved with the adhesive, but the ultraviolet absorbent is used as the main solvent of the inkjet ink and the adhesive. By setting the composition so as to be soluble in the main solvent, precipitation of the UV absorber can be prevented and a high-quality transfer product can be obtained.

In one embodiment of the hydraulic transfer film,
The main solvent of the inkjet ink is propylene glycol monomethyl ether acetate,
The main solvent of the adhesion agent is diethylene glycol monobutyl ether acetate or ethylene glycol monobutyl ether.

  According to the hydraulic transfer film of this embodiment, the main solvent of the inkjet ink is propylene glycol monomethyl ether acetate, and the main solvent of the adhesive is diethylene glycol monobutyl ether acetate or ethylene glycol monobutyl ether. Thereby, the print quality and the quality of the transferred material can be improved, and the transfer process can be stabilized.

  In one embodiment, the thickness of the ink absorbing layer is 2 μm to 7 μm.

  According to the hydraulic transfer film of this embodiment, since the thickness of the ink absorption layer is 2 μm to 7 μm, it is possible to achieve both the ultraviolet absorption effect and the transfer process.

  According to the hydraulic transfer film of the present invention, a benzotriazole-based ultraviolet absorber is used in the ink absorption layer that must maintain the ink absorption performance, transfer flexibility, and transfer article position. Thereby, it is hard to produce a malfunction in a printing process and a transfer process, exhibiting efficient ultraviolet-ray resistance.

It is sectional drawing which shows the film for hydraulic transfer of one Embodiment of this invention. It is explanatory drawing explaining the transfer process of the film for hydraulic transfer. It is sectional drawing of the transfer product using the film for hydraulic transfer. It is a table | surface which shows various characteristics at the time of mix | blending 2- (2'-hydroxy-5'-t-octylphenyl) benzotriazole in the range of 1 to 15% in an acrylic resin.

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

(Structure of hydraulic transfer film)
FIG. 1 is a simplified cross-sectional view showing a hydraulic transfer film according to an embodiment of the present invention. As shown in FIG. 1, the hydraulic transfer film 1 includes a support film 10, an ink absorption layer 20, and a pattern layer 30. The ink absorbing layer 20 is coated on one side of the support film 10. The pattern layer 30 is printed on the ink absorption layer 20.

  The ink absorbing layer 20 includes an acrylic resin-based ink-receiving resin 21 and a benzotriazole-based ultraviolet absorber 22 provided on the ink-receiving resin 21. The ink receiving resin 21 absorbs the solvent of the inkjet ink. The ultraviolet absorber 22 absorbs ultraviolet rays.

  The support film 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 formed into a sheet. What was formed in is used. As thickness of the support body film 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 film 10 and evaporating the non-aqueous solvent. The ink receptive resin 21 of the ink absorbing layer 20 is an acrylic resin. Examples of the acrylic resin include poly (meth) methyl acrylate, poly (meth) butyl acrylate, and (meth) methyl acrylate- (meth). ) One type of butyl acrylate copolymer, methyl (meth) acrylate- (meth) acrylic acid 2-hydroxyethyl copolymer, or a mixture of two or more types 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. In addition, in order to adjust the glass transition point, there is also a case where a small amount of dioctyl phthalate described later is added.

  The ultraviolet absorbent 22 is dissolved in advance in a coating liquid used for forming the ink absorbing layer 20, and the coating liquid of the ink absorbing layer 20 is dried and solidified after coating, so that the inside of the ink absorbing layer 20 is obtained. To be scattered.

  It is desirable that the ultraviolet absorber 22 has high solubility in the main solvent of the acrylic resin dispersion solution. For example, when ethyl acetate is used as the main solvent, 2- (2′-hydroxy-5′-t-octylphenyl) benzotriazole (dissolves about 20 g in 100 g of ethyl acetate), 2- (3,5-di- -Tert-amyl-2-hydroxyphenyl) benzotriazole (also about 15 g dissolved) and 2- (2-hydroxy-5-methylphenyl) benzotriazole (also about 5 g dissolved) are suitable, and higher solubility is desirable.

  As a result of our study, the support film 10 of the hydraulic transfer film 1 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.

  Furthermore, after adding a small amount (˜1%) of an isocyanate solution diluted with an ethyl acetate solvent to a coating liquid using the above-mentioned acrylic resin as a resin component and using ethyl acetate as a solvent, it is applied to the surface of water-soluble polyvinyl alcohol. By working and drying, it is possible to obtain a hydraulic transfer film 1 that has both printability and flexibility in the transfer process. By adding the isocyanate solution, the ink absorbing layer 20 can partially form a three-dimensional network structure with isocyanate groups. 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.

  In the case where the benzotriazole type ultraviolet absorber 22 such as 2- (2′-hydroxy-5′-t-octylphenyl) benzotriazole or 2- (5-methyl-2-hydroxyphenyl) benzotriazole is 10% or less It was revealed that the ink absorbing layer 20 can maintain good characteristics without hindering the isocyanate reaction.

  As a comparative experiment, a coating liquid made of an ethyl acetate solvent was prototyped and examined using a commonly used polyurethane resin as a material for the ink absorbing layer 20. Although it tries to stretch when the molded product is pressed against the film, it tries to return to its original shape due to its elastic force. As a result, it was improperly transferred with wrinkles on the film. .

  In addition, as a method of applying a coating solution obtained by dissolving an acrylic resin in a non-aqueous solvent on the support film 10, coating means such as gravure coating, roll coating, die coating, and bar coating can be used. The body film 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 1, in order to achieve both printability and transferability, It is desirable that the thickness is 2 to 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 film 10, the ink absorption layer 20 is formed by heating and drying 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.

(Method for producing hydraulic transfer film)
As an example of the first production method, an acrylic resin dispersion having a solid content of 20% by weight made of an ethyl acetate solvent is prepared, and an organic ultraviolet absorber weighed in advance in the dispersion is added while stirring.

  The acrylic resin used in this example is an isocyanate curable acrylic resin, and the ink absorption performance and flexibility at the time of transfer can be adjusted by adjusting the addition amount of the isocyanate crosslinking agent. A predetermined isocyanate crosslinking agent is added to the acrylic resin dispersion and sufficiently stirred.

  For example, when the acrylic resin dispersion liquid with 10% solid content of 20% by weight is 100 g, 20 × 0.10 = 2 g with respect to the solid content of 20 g, and the acrylic resin dispersion liquid absorbs 2 g of organic ultraviolet rays to 100 g. Add the agent. Then, stir with a stirrer for 60 minutes.

  The acrylic resin dispersion thus prepared is further diluted with ethyl acetate so that the solid content concentration becomes 15%.

  Next, on the support film cut to A3 size, the acrylic resin dispersion is coated using a wire bar (No. 14) and dried in an oven at 70 ° C. for 5 minutes, so that the film for hydraulic transfer has a thickness of 4 μm. Got. This manufacturing method was mainly used for test evaluation of various preparation amounts and for small-scale production.

  As the second production method, after mixing the acrylic resin dispersion and the zinc oxide dispersion in the same manner as in the first production method, the support film wound in a roll shape having a width of 50 cm was uniformly coated with a gravure coater. Thereafter, it was introduced into a drying furnace in-line and dried to form an ink absorbing layer having a thickness of 4 μm and wound into a roll.

(Picture transfer product manufactured from hydraulic transfer film)
FIG. 2 is an explanatory diagram for performing transfer using the hydraulic transfer film 1 of the present invention. In the hydraulic transfer film 1, an ink absorbing layer 20 in which an ultraviolet absorbent 22 is introduced in advance is formed on a support film 10, and a pattern layer 30 is formed on the ink absorbing layer 20 by ink jet printing described later as required. Form. The hydraulic transfer film 1 on which the pattern layer 30 is formed floats on the water surface 11 on the support film 10 side. After a predetermined time has elapsed, an organic solvent made of xylene, butyl acetate, ethylbenzene, methoxybutyl acetate, propylene glycol monobutyl ether acetate, ethyl ethoxypropylate, or the like is applied to the pattern layer 30 side by a spray gun method, and ABS resin 40 Is pressed from the pattern layer 30 side so that the pattern layer 30 and the ink absorbing layer 20 are in close contact with the ABS resin 40. Thereafter, the pattern layer 30, the ink absorbing layer 20, and the semi-dissolved support film 10 remain in the ABS resin 40 taken out from the water surface.

  Next, the support film 10 is washed away with warm water, and the ABS resin 40 with the pattern layer 30 and the ink absorption layer 20 is dried to remove moisture in an oven.

  FIG. 3 is a schematic cross-sectional view of a picture transfer product. The urethane clear 50 is applied from the ink absorbing layer 20 side. The image transfer product obtained in this way is visually recognized from the urethane clear 50 side, and ultraviolet light that causes discoloration of the image transfer product also enters. Since the ultraviolet absorber 22 having the effect of blocking ultraviolet rays is introduced into the pattern layer 30, it is difficult to irradiate the pattern layer 30 colored with the inkjet ink with ultraviolet rays.

  FIG. 4 shows various characteristics when 2- (2′-hydroxy-5′-t-octylphenyl) benzotriazole is blended in the range of 1 to 15% in the acrylic resin of this example.

  In the surface observation evaluation after one month after the coating, no precipitation or the like occurs even if the solid weight ratio of 12% is added to the acrylic resin (ink-receptive resin) or one month after coating. Good characteristics were maintained. On the other hand, when the solid weight ratio was 15%, cracks or bleed-out occurred with time on the film surface, which was inappropriate.

  Subsequently, as a result of printing by ink jet printing, bleeding out that was not seen before printing occurred in 12% of the samples, which was inappropriate.

  Subsequently, there was no problem in the transfer process under all conditions of 10% or less.

  From the above results, it can be seen that 2- (2′-hydroxy-5′-t-octylphenyl) benzotriazole is suitable for blending of 10% or less in a hydraulic transfer film having an acrylic resin that absorbs inkjet ink. .

  In addition, the thickness of the ink absorbing layer is preferably in the range of 2 to 7 μm in terms of both printability and transferability. In order to exhibit the ultraviolet absorbing effect at this thickness, the blending ratio is 3% or more. It is desirable to do. That is, the solid weight ratio of the ultraviolet absorber 22 to the ink receiving resin 21 is 3 to 10%.

  Further, the ultraviolet absorber used in this example has a solubility of 5% or more by solvent weight ratio with respect to all of the main solvent of the receptive resin dispersion, the main solvent of the inkjet ink, and the main solvent of the adhesive. Select. Thereby, it is possible to obtain a transfer product with good quality after printing and after transfer.

  In addition, when the main solvent of the adhesion agent is diethylene glycol monobutyl ether acetate or ethylene glycol monobutyl ether and the main solvent of the inkjet ink is propylene glycol monomethyl ether acetate, 2- (2′-hydroxy-) is used as the ultraviolet absorber. 5'-t-octylphenyl) benzotriazole and 2- (5-methyl-2-hydroxyphenyl) benzotriazole are preferred.

  Further, by creating a transfer subject using the hydraulic transfer film of the present invention, the following advantages can be obtained while obtaining UV resistance.

  In the thin pattern portion, since the amount of the binder resin of the pattern layer 30 is small, the adhesiveness to the transfer surface is not good as it is. However, in the present invention, the transparent ink absorbing layer 20 is formed so as to cover the pattern layer 30. Therefore, adhesion and durability are improved.

  Since the binder resin that can draw a pattern by the ink jet method has limited solvent resistance, the solvent used for the top coat after the transfer (formation of a transparent protective layer) is limited, but the ink absorbing layer 20 having more solvent resistance. There are no restrictions on the top coat.

(Absorption spectrum of hydraulic transfer film)
Spectral spectrum of hydraulic transfer film with UV-absorbing agent blended with ink-receptive resin, using spectrophotometer (U-3900 manufactured by Hitachi), wavelength of 200 ~ 800nm with support layer attached to support film Measurement was performed over a range, and the light shielding characteristics in the ultraviolet light region of 380 nm or less were confirmed.

  When 2- (2′-hydroxy-5′-t-octylphenyl) benzotriazole is blended in an ink absorption layer having a thickness of 4 μm with a solid weight ratio of 10%, the absorption rate of ultraviolet light is 99% or more, and the solid weight ratio When 5% was blended, it was about 90%. Further, when the solid weight ratio was 3%, it was about 70%, and when it was 1%, it was about 50%.

(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>
As the resin contained in the composition of the non-aqueous inkjet ink used in the present invention, both the constraint condition required from the viewpoint of inkjet dischargeability and the constraint condition required from the viewpoint of drawability on the hydraulic transfer film 1 are made compatible. It 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 of the ink binder is preferably 5000 to 20000, and more preferably 7000 to 15000. When the weight average molecular weight is smaller than the above range, the film forming property, color fixing property and glossiness which are desired to be given a function by adding a resin cannot be obtained. 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 ink binder resin is desirably lower than the weight average molecular weight of the ink absorbing layer 20. The pattern layer 30 and the ink absorbing layer 20 are softened by coating an activator made of an organic solvent in the transfer step. The organic solvent can be appropriately selected depending on the characteristics of the hydraulic transfer film 1.

  However, if the weight average molecular weight of the binder resin of the pattern layer 30 is higher, the portion of the pattern layer 30 becomes difficult to be softened by the activator, and the activator is uniform in the ink absorbing layer 20 located under the pattern layer 30. This is because the difference in pattern density increases the difference in flexibility (attachment at the time of transfer).

  The blending amount of the acrylic resin in the ink composition is preferably 2 to 8% by weight. When the amount of the resin is less than the above range, there is a problem that the shape retention after landing is weak or the fixability of the pigment is deteriorated. Conversely, when the amount is more than the above range, the viscosity of the ink composition is high. Thus, the ejection stability of the ink jet is deteriorated.

  In addition to the above resins, add a small amount of ester resin, urethane resin, rosin resin, alkyd resin, styrene-acrylic resin, cellulose resin, etc., as long as the discharge performance and drawing performance do not deteriorate. Thus, it is also possible to supplement characteristics such as landing shape and color developability.

<Solvent>
The main solvent contained in the composition of the non-aqueous inkjet ink of the present invention can dissolve the pigment, the dispersant for dispersing the pigment, the acrylic resin, and can provide solution characteristics suitable for inkjet ejection. Glycol ester and glycol ether solvents are preferred.

  Examples of the glycol ester solvent 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, diethylene glycol Examples include propylene glycol monomethyl ether acetate.

  Since 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 resin is widened.

  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 preferable that the solvent contains a glycol ester solvent. Among them, diethylene glycol mono-n-butyl ether acetate and propylene glycol monomethyl ether acetate are preferable as those that stably disperse the binder resin and have a 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 serve as indices for stably discharging microdroplets from the inkjet head, and their mixing properties are good Therefore, it is often the case that a plurality of glycol ether solvents are mixed and blended in a form that matches the characteristics of the inkjet head and the usage environment.

  A low boiling point solvent has a lower viscosity than a high boiling point. Examples of the low boiling point glycol ether solvent that can contribute to the reduction in the viscosity of the entire ink composition include ethylene glycol monomethyl ether (124 ° C.), ethylene glycol monoethyl ether (135 ° C.), and ethylene glycol monoisopropyl 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- Examples thereof include n-propyl ether (150 ° C.), propylene glycol mono-n-butyl ether (170 ° C.), dipropylene glycol dimethyl ether (171 ° C.) and the like. Of these, propylene glycol monomethyl ether and propylene glycol mono-n-butyl ether are preferable.

  Examples of glycol ether solvents that have a high boiling point and can slow down drying properties that cause nozzle clogging include diethylene glycol monomethyl ether (194 ° C.), diethylene glycol monoethyl ether (202 ° C.), diethylene glycol diethyl ether (189 ° C.), and 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.) and the like. Showing).

  Among these, 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 solvent alone or in combination, ink suitable for printability and transferability in the subsequent process is prepared for the hydraulic transfer film 1 having the ink absorption layer 20. It becomes possible to do.

(Inkjet ink manufacturing method)
The composition of the non-aqueous inkjet ink 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 inkjet ink composition.

(Inkjet printing on hydraulic transfer film)
Ink jet printing on the hydraulic transfer film 1 using the composition of the non-aqueous ink jet ink according to the present invention is performed by ejecting fine droplets of the ink composition by an ink jet apparatus and landing on the ink absorbing layer 20. It is formed. 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.

  That is, in the pattern layer 30, after the ink composition ejected from the ink jet apparatus has landed on the ink absorption layer 20, the solvent component of the ink composition is absorbed by the ink absorption layer 20, and the solid content remains on the ink absorption layer 20. Formed with.

(Inkjet ink formulation example)
Pigment Blue 15: 4 as a pigment is 10% by weight, Dispersbyk-2001 made by BYK Chemie is used as a pigment dispersant in an amount of 8% by weight, and propylene glycol monomethyl ether acetate is 82% by weight. I got a product.

  Next, an acrylic copolymer resin solution was prepared by radical polymerization using propylene glycol monomethyl ether acetate solvent with butyl acrylate and diethylaminoethyl methacrylate monomers.

  40% by weight of this pigment dispersion, 10% by weight of resin liquid, 20% by weight of diethylene glycol mono-n-butyl ether, 10% by weight of propylene glycol monomethyl ether acetate, and 10% by weight of propylene glycol monomethyl ether are mixed. Ink was obtained.

  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.

DESCRIPTION OF SYMBOLS 1 Hydraulic transfer film 10 Support film 20 Ink absorption layer 21 Ink receiving resin 22 Ultraviolet absorber 30 Picture layer

Claims (5)

A support film made of a water-soluble or water-swellable resin;
An ink absorbing layer coated on one side of the support film,
The ink absorbing layer is
An acrylic resin-based ink-receiving resin that absorbs the solvent of the inkjet ink;
A benzotriazole-based UV absorber provided in the ink-receiving resin;
The film for hydraulic transfer, wherein the solid weight ratio of the ultraviolet absorber to the ink-receiving resin is 3 to 10%. In the hydraulic transfer film according to claim 1,
The ink receptive resin is an acrylic resin-based isocyanate cross-linked product obtained by solidifying a coating liquid composed of an ethyl acetate solvent.
The film for hydraulic transfer, wherein the ultraviolet absorber is 2- (2′-hydroxy-5′-t-octylphenyl) benzotriazole or 2- (5-methyl-2-hydroxyphenyl) benzotriazole . In the hydraulic transfer film according to claim 1 or 2,
Provided with a pattern layer printed by inkjet ink on the ink absorption layer,
The ink receptive resin is semi-dissolved by the adhesive and can be fixed on the surface of the transfer object.
The film for hydraulic transfer, wherein the ultraviolet absorber is soluble in the main solvent of the inkjet ink and the main solvent of the adhesive. In the hydraulic transfer film according to claim 3,
The main solvent of the inkjet ink is propylene glycol monomethyl ether acetate,
The film for hydraulic transfer, wherein the main solvent of the adhesive is diethylene glycol monobutyl ether acetate or ethylene glycol monobutyl ether. In the hydraulic transfer film according to any one of claims 1 to 4,
The film for hydraulic transfer, wherein the ink absorbing layer has a thickness of 2 μm to 7 μm.

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