JP5742337B2 - Offset printing method and decorative molded product manufacturing method - Google Patents

Description

  The present invention relates to an offset printing method and a method for manufacturing a decorative molded product.

  Conventionally, an offset printing method is known as a method for continuously forming a printed pattern on a substrate. In general, in the offset printing method, water is applied sequentially to the hydrophilic layer of the lithographic plate, the ink, and ink is applied to the oleophilic layer, and the ink remaining on the oleophilic layer is transferred onto the blanket by pressing a soft blanket. By pressing the blanket against the surface of the substrate, printing is performed by bringing the ink transferred onto the blanket into contact with the surface of the substrate (for example, see Patent Document 1).

  However, when forming a multicolor printing pattern by these conventional offset printing methods, it is necessary to repeat the printing process for each ink of different colors, resulting in increased work steps and inferior productivity. Or, since it is necessary to provide an offset printing machine for each color, there are problems such as high initial cost and a large site area. In addition, in order to perform high-quality multicolor printing without color misregistration, it is necessary to accurately match the printing positions in the printing process for each color, and there is a problem that printing accuracy is unstable.

JP 2000-127640 A

  SUMMARY OF THE INVENTION An object of the present invention is to provide an offset printing method capable of performing multicolor printing on a printing material with a small number of steps using a compact printing apparatus and having stable printing accuracy.

The present inventors have found that the problems result of extensive studies to solve the, transferring the printing layer of the transfer sheet obtained by laminating at least a multi-color printing layer on a base film on the blanket, the substrate It was found that the above-mentioned problems can be solved by an offset printing method in which the film is pressed onto the blanket and the printed layer is copied.
That is, the present invention
1. Using a transfer sheet formed by laminating at least multicolor printing layer on a base film, coating an active agent onto (A) the printed layer, the step of softening at least a portion of the printing layer, (B) the the transfer sheet pressed between the first impression cylinder and the blanket cylinder, the printing substrate is pressed onto the blanket by softened step Nikki copy to the print layer continuously on the blanket, and (C) pushing means, offset printing process which comprises the step (B) by the print layer taken copy on the blanket else taking continuously copies on the substrate subjected to decoration to the substrate step,
2. The printed material is in the form of a sheet or a film, and the pressing means is a second impression cylinder. In the step (C), the printed material is pressurized between the blanket cylinder and the second impression cylinder and softened. 2. The offset printing method according to 1 above, wherein the printed layer is continuously copied onto the substrate.
3. The offset printing method according to the above 1 or 2, wherein the printing layer is formed from an ink containing a cellulose resin as a vehicle.
4). The above 1 to 3 in which the activator contains 1 to 20% by mass of a phthalate ester, 60 to 90% by mass of an alcohol, 0 to 20% by mass of an ester excluding the phthalate ester, and 1 to 20% by mass of a ketone. The offset printing method according to any one of
5. In addition to the above (A) ~ (C) step, further (D) to the transferred the printing layer, offset printing method according to any one of the above 1 to 4, including the step of forming a protective film,
6). 6. The offset printing method according to any one of 1 to 5 above, wherein the base film is formed using one or more selected from polyolefin resins and polyester resins. The manufacturing method of the decorative molded product characterized by using the offset printing method in any one of said 1-6 is provided.

  According to the offset printing method of the present invention, it is possible to perform multicolor printing on a printing object with a small number of steps using a compact printing apparatus, and it is possible to perform offset printing with stable printing accuracy.

It is a schematic sectional drawing which shows an example of a structure of the transfer sheet used by this invention. It is a schematic diagram which shows the process of apply | coating an activator on the printing layer of a transfer sheet, and softening at least one part of this printing layer. It is a schematic diagram showing a step of pressing the transfer sheet between the first impression cylinder and the blanket cylinder and continuously copying the softened printing layer on the blanket. It is a schematic diagram which shows the process which presses a to-be-printed material on a blanket by a press means, and copies the softened printing layer continuously on a to-be-printed material, and decorates. It is a schematic diagram which shows the outline of an example of the offset printing method of this invention.

[Printing method]
The offset printing method of the present invention uses a transfer sheet obtained by laminating at least a printing layer on a base film, and (A) a step of applying an activator on the printing layer and softening at least a part of the printing layer. (B) a step in which the transfer sheet is pressed between the first impression cylinder and the blanket cylinder, and the softened printing layer is continuously transferred onto the blanket; and (C) the printed material is placed on the blanket by the pressing means. The method includes a step of pressing and decorating the printed material by continuously copying the printed layer copied on the blanket by the step (B) onto the printed material.
The offset printing method of the present invention may be a single-wafer method or a winding method.

<Process (A)>
In the step (A), as shown in FIGS. 2 and 5, the activator 3 is applied on the printing layer 2 of the transfer sheet 10 (see FIG. 2A-1) (see FIG. 2A-2). If necessary, the surface of the activator is made uniform with a smoothing roll, and at least a part of the printing layer 2 is dissolved or swollen to be activated to obtain a softened printing layer 4 (FIG. 2A-3). ))).
The activator 3 is preferably applied by a spray coating method, a Miya bar coating method, a gravure coating method, or the like. The application amount of the activator 3 is usually 1 to 50 g / m ² , preferably 3 to 30 g / m ² , and more preferably 10 to 20 g / m ² .
As a specific example of this step, the transfer sheet 10 is supplied so that the printing layer 2 side faces upward, and the activator 3 is sprayed or applied, or as shown in FIG. There is a method of supplying and applying between the activator supply roll 24 and the third impression cylinder 23 so that the side faces the activator supply roll 24 side.

  Further, after the activator 3 is applied on the printing layer 2, before the activator 3 soaks into the printing layer 2 and softens the ink, a smoothing roll (not shown) is applied to the coated surface, It is preferable to make the surface of the active agent 3 uniform. By adopting the smoothing roll, the coated surface of the applied activator 3 becomes uniform, and excellent design properties (transparency) and design reproducibility can be imparted to the printed material 6. In the present invention, the time until the activator 3 applied on the printing layer 2 soaks into the printing layer 2 and forms the printing layer 4 in which the ink is redissolved and softened is usually about 5 seconds to 3 minutes. .

  The smoothing roll is a roll having a mirror-like or groove-like plate on the surface, and the mirror-like or groove-like plate is coated with the activator 3 while rotating forward or counterclockwise with respect to the traveling direction of the transfer sheet 10. By hitting, the coated surface is made uniform. When the surface of the smoothing roll has a groove-shaped plate, the depth of the groove can be appropriately set depending on the material of the base film 1, the coating amount of the activator 3, the state of the coating surface, and the like. 300 μm is preferable, 20 to 200 μm is more preferable, and there may be one groove or a plurality of grooves. The smoothing roll is preferably applied horizontally to the coating surface of the activator 3 from the viewpoint of making the coating surface of the activator 3 uniform, and preferably swings in the width direction of the transfer sheet 10. The rocking speed is usually about 1 to 20 mm / second, preferably 1 to 10 mm / second, and more preferably 2 to 7 mm / second. Moreover, what is necessary is just to set suitably the internal diameter, rotation speed, etc. of said smoothing roll by the material of the base film 1, the application amount of the activator 3, the state of an application surface, etc.

  The activator 3 has a function of dissolving or swelling at least a part of the printing layer 2 for transfer in the transfer sheet 10 and softening it, and therefore requires a certain amount of time. On the other hand, it is important not to volatilize until the process of transferring the printing layer to the printing surface of the printing material is completed. Therefore, in order to transfer the print layer to the printing material under optimum conditions in various usage situations, it is important to appropriately adjust the composition and coating amount of the activator 3 and the use conditions of the smoothing roll.

<Process (B)>
In the step (B), as shown in FIGS. 3 and 5, the transfer sheet 10 is pressed between the first impression cylinder 21 and the blanket cylinder 20, and the softened printing layer 4 is continuously copied onto the blanket 5. It is a process.
The blanket 5 wound around the blanket cylinder 20 is not particularly limited as long as it is a flexible and elastic member capable of holding the printing layer 4 temporarily softened on its surface, but is made of silicone rubber, urethane rubber, nitrile. Various rubber blankets conventionally used in offset printing, such as rubber, butadiene rubber, fluoro rubber, ethylene propylene rubber, chloroprene rubber, acrylic rubber, butyl rubber, and natural rubber, can be used.
In the step (B), the ink applied on the lithographic original plate in the conventional offset printing method is copied onto a blanket. Instead of this lithographic original plate, the substrate film 1 obtained in the step (A) is used. A transfer sheet 10 having a softened printing layer 4 is used.

<Process (C)>
In the step (C), as shown in FIG. 4, the printed material 6 is pressed onto the blanket 5 by pressing means, and the softened printing layer 4 is continuously copied onto the printed material 6 and decorated. It is.
The pressing means can be selected according to the shape or the like of the substrate 6 and a method capable of continuously pressing the substrate 6 can be selected as appropriate. When the substrate 6 has a three-dimensional shape, a robot arm or the like can be used as the pressing means. However, when the substrate 6 is in the form of a sheet or film, a plate-like member is used. The printed product 6 is pressed between the blanket cylinder 20 and the flat plate member, or the second impression cylinder 22 is used as shown in FIG. 5, and the printed article 6 is placed between the blanket cylinder 20 and the second impression cylinder 22. A method in which the printing layer 4 softened by pressurization is continuously copied onto the substrate 6 is preferable.
The step (C) can be performed in the same manner as the step of copying the printing layer from the blanket to the substrate in the conventional offset printing method.
In the case of the winding method, the step (B) and the step (C) are preferably performed simultaneously in parallel.

<Process (D)>
In the offset printing method of the present invention, in addition to the steps (A) to (C), a step (D) of forming a protective film on the transferred print layer may be added.
In the step (D), the printing layer transferred to the transfer surface of the printing material in the step (C) is coated as necessary to improve surface strength, protect the surface, and adjust the surface gloss. A transparent protective film is formed. As this transparent protective film, for example, a thermoplastic resin, a thermosetting resin, an ultraviolet curable resin, or the like, specifically, a urethane resin, an epoxy resin, an acrylic resin, a fluorine resin, a silicon resin, or the like is used. As a coating method, known methods such as spray coating, electrostatic coating, brush coating, and dip coating can be used.

[Transfer sheet]
The transfer sheet used in the transfer printing method of the present invention is formed by laminating at least the printing layer 2 on the base film 1, and at least a part of the printing layer 2 is dissolved or swollen using the activator 3 to be softened. Then, the printed material 6 can be decorated by transferring the softened printing layer 4 onto the printed material 6 by transfer printing.
FIG. 1 is a schematic cross-sectional view showing an example of the configuration of a transfer sheet 10 used in the present invention. The transfer sheet 10 is provided with a printing layer 2 composed of a plurality of pattern layers on a base film 1 by gravure printing or the like.

[Base film]
The base film 1 is not particularly limited as long as it is normally used as a printing sheet, but is preferably water-insoluble, and generally a plastic film can be suitably used. Examples of the plastic include those made of various synthetic resins. Synthetic resins include polyethylene resins such as polyethylene, polypropylene, polymethylpentene, and olefinic thermoplastic elastomers; vinyl resins such as polyvinyl chloride, polyvinylidene chloride, and ethylene-vinyl alcohol copolymers; polyethylene terephthalate and polybutylene terephthalate. Polyester resins such as polyethylene naphthalate and polyester-based thermoplastic elastomers; Acrylic resins such as poly (meth) methyl acrylate, poly (meth) ethyl acrylate and poly (meth) butyl acrylate; nylon 6 or nylon 66, etc. Representative polyamide resin; cellulose triacetate resin; cellophane; polystyrene; polycarbonate resin; polyarylate resin.
Of these, polyolefin resins and polyester resins are preferably used from the viewpoints of cost, mechanical strength, and the like, and stretched polypropylene and polyethylene terephthalate are particularly preferable from the viewpoints of handling properties and costs.

Although the thickness of the base film 1 is not specifically limited, The range of 10-400 micrometers is suitable. When it is 10 μm or more, the uniformity of the film is good and the production stability is high. On the other hand, when it is 400 μm or less, the rigidity of the film does not become too high and the printability is excellent. From the above viewpoint, the thickness of the base film 1 is more preferably in the range of 20 to 200 μm.
Moreover, an additive may be mix | blended with the synthetic resin used for the base film 1 as needed. Examples of the additive include a filler, a flame retardant, an antioxidant, a lubricant, a foaming agent, an ultraviolet absorber, and a light stabilizer.
From the viewpoint of peelability from the printing layer 2, the base film 1 may be provided with a release layer or a peeling layer on the surface on the printing layer 2 side.

[Print layer]
The transfer sheet 10 has a printing layer 2 for transfer, and as the ink for forming the printing layer 2, a conventionally known ink can be appropriately selected and used.
Examples of the pigment contained in the ink include inorganic materials such as titanium white, antimony white, lead white, iron black, yellow lead, titanium yellow, vermilion, cadmium red, ultramarine, cobalt blue, pearl pigment, and silver pigment such as aluminum paste. Pigments: Organic pigments such as carbo black (black ink), benzidine yellow, isoindolinone yellow, polyazo red, quinacridone red, indanthrene blue, and phthalocyanine blue can be used.

The vehicle contained in the ink is not particularly limited. For example, various oils such as linseed oil, soybean oil, synthetic drying oil; natural resins such as rosin, hardened rosin, rosin ester, polymerized rosin; phenol resin Synthetic resins such as rosin-modified phenolic resin, maleic acid resin, alkyd resin, petroleum resin, vinyl resin, acrylic resin, polyamide resin, epoxy resin, aminoalkyd resin, fluororesin; nitrocellulose, cellulose acetate butyrate Examples thereof include cellulose resins such as resins and ethyl cellulose; rubber derivatives such as chlorinated rubber and cyclized rubber; and other caseins, dextrins, and zeins. Among these, it is preferable to use a cellulose resin from the viewpoint of transferability to a blanket.
The weight average molecular weight of the cellulose resin is preferably 100,000 or more, more preferably 300,000 to 6,000,000, and most preferably 500,000 to 2,000,000.

Moreover, it is preferable to add an ultraviolet absorber or a light stabilizer to the ink, and the weather resistance of the printing layer transferred to the transfer medium can be improved.
Examples of the ultraviolet absorber include organic compounds such as benzotriazole, benzophenone, and salicylic acid ester, and inorganic compounds such as fine particle zinc oxide and cerium oxide having a particle size of 0.2 μm or less. Examples thereof include hindered amine radical scavengers such as bis- (2,2,6,6-tetramethyl-4-piperidinyl) sebacate and radical scavengers such as piperidine radical scavengers.
In addition, content of these ultraviolet absorbers and light stabilizers is about 0.5 to 10% by mass on the basis of the total amount of ink.

  The solvent contained in the ink is not particularly limited, and aliphatic hydrocarbons, aromatic hydrocarbons, halogenated hydrocarbons, alcohols, ketones, ethers, acetate esters, esters, cellosolve, Nitro hydrocarbons, nitriles, amines, other acetals, acids, furans and the like can be mentioned. Among these, in consideration of the environment, it is preferable not to use aromatic hydrocarbons such as benzene, toluene, xylene, etc., and ethyl acetate, propyl acetate, butyl acetate, cellosolve, cyclohexanone, ethyl alcohol, isopropyl alcohol, isobutyl alcohol, Methyl ethyl ketone, methyl isobutyl ketone, propylene glycol mono-butyl ether, propylene glycol, and the like are preferably used from the viewpoint of solubility with an active agent. In addition, these solvents can be used individually by 1 type or in mixture of 2 or more types.

Although it does not specifically limit as a method of forming the printing layer 2, For example, it can form by offset printing, silk screen printing, inkjet printing, gravure printing, etc.
A printing layer 2 is formed on one surface of the base film 1 by gravure printing or the like. When the multicolor printing layer 2 is formed, the printing layer 2 can be formed by providing two or more pattern layers. In this overprinting, for example, when printing a color photograph or the like, it is common to provide 3 to 7 picture layers. In four-color printing, for example, C (cyan), M (magenta), Y (yellow), and K (black) are generally used. In conventional offset printing, when performing multi-color printing, it is necessary to repeat the transfer process of the printing layer from the original plate to the blanket and the transfer process of the printing layer from the blanket onto the substrate depending on the number of colors. However, when a transfer sheet comprising a plurality of pattern layers is used for the printing layer, even if the number of colors is large, there is no need to repeat the above series of steps, so the printing apparatus becomes compact and the printing process is greatly increased. In addition, since no color misregistration occurs, it is extremely useful in practice.

Although there is no restriction | limiting in particular in the thickness of each pattern layer which comprises the printing layer 2, Usually, about 0.1-10 micrometers, Preferably it is 0.5-5 micrometers.
Further, the amount of ink applied when forming each pattern layer is not particularly limited as long as the thickness of each pattern layer is within the above range, and is preferably 0.5 to 1.5 g / m ² . More preferably, it is 0.7-1.4 g / m < ² >.

[Activator]
The activator is applied to the printing layer 2 of the transfer sheet 10 to appropriately dissolve or swell and soften (activate) at least a part of the printing layer 2. The state can be maintained until it is transferred.
The activator used in the present invention can be used as long as it dissolves or swells and softens at least a part of the printing layer 2. For example, a solvent such as esters, alcohols, and ketones is used. In particular, those containing 1 to 20% by mass of a phthalate ester, 60 to 90% by mass of alcohols, and 1 to 20% by mass of ketones are preferably used.

The activator used in the present invention preferably contains a phthalate ester as a plasticizer. The plasticizer is for imparting the activator with a function of softening the ink of the printing layer.
Preferred examples of the phthalic acid ester include phthalic acid diesters such as dimethyl phthalate, dibutyl phthalate, dioctyl phthalate, and diisooctyl phthalate. Of these, dimethyl phthalate and dibutyl phthalate are more preferable, and among them, dimethyl phthalate is preferable from the viewpoint of stabilizing the active state and evaporating with other solvents appropriately.

  Alcohols include ethyl alcohol (boiling point 78 ° C.), isopropyl alcohol (boiling point 82 ° C.), tert-butyl alcohol (boiling point 84 ° C.), n-propyl alcohol (boiling point 97 ° C.), 2-butyl alcohol (boiling point 99 ° C.). Examples include low-boiling alcohols having a boiling point of 70 to 100 ° C., high-boiling alcohols having a boiling point of more than 100 to 130 ° C. such as isobutyl alcohol (boiling point 108 ° C.), n-butyl alcohol (boiling point 117 ° C.), and the like. , Or a combination of two or more. Of these, isopropyl alcohol and isobutyl alcohol are preferred. In addition, it is preferable to use a low-boiling alcohol and a high-boiling alcohol in combination, particularly a combination of isopropyl alcohol and isobutyl alcohol, and a mass ratio of the blend is preferably 1: 7 to 1: 1, and 1: 7. ~ 1: 2 is more preferred.

The ketones preferably include those having a boiling point of 200 ° C. or lower, such as methyl ethyl ketone (boiling point 80 ° C.), methyl isobutyl ketone (boiling point 116 ° C.), dibutyl ketone (boiling point 187 ° C.), and diisobutyl ketone (boiling point 168 ° C.). Among these, at least one selected from dibutyl ketone and diisobutyl ketone is preferable.
To the activator used in the present invention, esters other than phthalate may be added.
Specific examples of esters other than phthalate esters include ethyl acetate, propyl acetate, butyl acetate, isobutyl acetate, sec-butyl acetate, tert-butyl acetate, methoxybutyl acetate, butyl carbitol acetate, and dibutyl oxalate. Is mentioned. Of these, acetates are preferable, and at least one selected from ethyl acetate, butyl acetate, and isobutyl acetate is preferable.

  The content of alcohol in the activator used in the present invention is preferably 60 to 90% by mass, and more preferably 70 to 90% by mass. It is preferable that content of ketones is 1-20 mass%, and 5-15 mass% is more preferable. Further, the content of the phthalate ester is preferably 1 to 20% by mass, and there is no problem that a part of the ink dissolves too early, and the pattern does not flow or distort. 15 mass% is more preferable, and 3-10 mass% is further more preferable. The content of esters other than phthalate is preferably 0 to 20% by mass, and more preferably 0 to 15% by mass.

The activator used in the present invention may contain aliphatic hydrocarbons and ethers.
Examples of the aliphatic hydrocarbon include heptane, 2-methylhexane, 3-methylhexane, 3-ethylpentane, octane, and isooctane. Among these, heptane is preferable.
Examples of ethers include butyl cellosolve and isoamyl cellosolve, and among these, butyl cellosolve is preferable.

  Moreover, about the activator used by this invention, the following resin can be added about 1-20 mass% with respect to a solvent, for example. Examples of this resin include vinyl halide polymers such as polyvinyl chloride and polyvinylidene chloride; styrene polymers such as polystyrene and polystyrene derivatives; vinyl ester polymers such as polyvinyl acetate; (meth) acrylic acid, itacon Polymers of ester derivatives of unsaturated carboxylic acids such as acid, crotonic acid, maleic acid or fumaric acid; polymers of nitrile derivatives or acid amide derivatives; N-methylol derivatives of acid amide derivatives of the above unsaturated carboxylic acids And the same N-alkylmethylol ether derivatives, glycidyl (meth) acrylate, allyl glycidyl ether, vinyl isocyanate, allyl isocyanate, 2-hydroxyethyl- (meth) acrylate, 2-hydroxypropyl- (meth) acrylate, ethylene glycol-mono ( A) Thermoplastic resins composed of monomers such as acrylates or copolymers; polyamide resins; polyester resins; phenol resins; melamine resins; urea resins; epoxy resins; diallyl phthalate resins Silicon resin; thermosetting resin such as polyurethane resin or modified resin or initial condensate thereof, natural resin, rosin and derivatives thereof, cellulose derivative such as nitrocellulose, natural or synthetic rubber, petroleum resin, cellulose acetate Examples thereof include cellulose resins such as butyrate (CAB) and nitrocellulose, and alkyd resins.

[Substrate]
Examples of the substrate 6 on which printing is performed by the transfer printing method of the present invention include those that are normally printed in the offset printing method, and those that are film-like, sheet-like, and plate-like are preferred. Moreover, it can also print on what has some unevenness | corrugations according to the elasticity of the blanket 5, As a specific example, the lid | cover of a container, the exterior material of a mobile telephone, etc. are mentioned.

[Decorative molded products]
The present invention also provides a method for producing a decorative molded product using the printing method.
The decorative molded product obtained by the above method is suitably used for automobile interior materials, building materials, furniture, electrical appliance housings, and the like that require particularly high design properties.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.
The decorative molded products obtained in each example were evaluated according to the following criteria.
(Evaluation method)
(1) Transfer state The transfer state of the pattern after the activated pattern was transferred to the substrate was visually evaluated. The evaluation criteria are as follows.
○: The pattern is uniformly transferred.
Δ: Some pictures are not printed.
×: The pattern is hardly transferred.

(2) Initial adhesion In the initial state in which the pattern was transferred to the printing material, the state of the pattern when water pressure was applied by a shower was visually evaluated. The evaluation criteria are as follows.
○: The pattern is not damaged by the water pressure, and the transferred state is maintained.
Δ: There is a portion where the pattern is slightly broken.
X: The design is broken and the design is impaired.

(3) Pinholes During transfer, pinholes due to solvent volatilization and the like were observed, and it was visually evaluated whether or not the pattern was transferred and the substrate was visible. The evaluation criteria are as follows.
○: No pinhole.
Δ: Some pinholes were observed, but there was no problem in practical use.
X: A pinhole occurred in the entire pattern.

(4) Pattern cracking After transferring the pattern to the printed material, the pattern was evaluated for cracks and fine cracks (pattern cracking) depending on the degree of dissolution of the printed layer by the activator. The evaluation criteria are as follows.
○: There is no pattern crack.
Δ: There is a crack in a part of the pattern.
X: There are fine pattern cracks and cracks as a whole, and there is no design reproducibility.

(5) Pattern flow After transferring the pattern to the printing material, the state (pattern flow) in which the pattern was displaced from the substrate or bent was evaluated due to the difference in the degree of dissolution of the printed layer by the activator. The evaluation criteria are as follows.
○: There is no pattern flow.
Δ: Pattern distortion in some areas.
X: A pattern flow occurs as a whole, and there is no design reproducibility.

(6) Yuzu skin, surface unevenness The surface smoothness after being transferred to a printed material and dried was evaluated by visual and tactile sensation. The evaluation criteria are as follows.
○: Mirror surface and smooth surface.
Δ: Partially mat-like and slightly uneven, but practically no problem.
X: The entire surface is uneven and rough.

(7) Appearance The design of the printed material after it was transferred to the printed material, dried, and provided with a transparent protective layer was visually evaluated in consideration of the design and elongation. The evaluation criteria are as follows.
○: Good designability.
Δ: There are some defects in the design.
X: The design property is impaired as a whole.

Production Example 1 (Preparation of active agent)
Activator 1 was prepared by mixing 5 parts by mass of dimethyl phthalate, 30 parts by mass of isopropyl alcohol, 55 parts by mass of isobutanol and 10 parts by mass of diisobutyl ketone.

Production Example 2 (Preparation of active agent)
Activator 2 was prepared by mixing 60 parts by mass of butyl carbitol acetate, 20 parts by mass of butyl cellosolve, 10 parts by mass of dibutyl phthalate and 10 parts by mass of xylene.

Example 1
(1) Preparation of transfer sheet A gravure ink [manufactured by DIC Graphics, “GT color”, vehicle: cellulosic resin (weight average molecular weight) on one side of a stretched polypropylene film having a thickness of 18 μm, using an electric gravure printer. : 1 million)], and transferring by providing a printing layer (wood grain pattern) having a thickness of 2 μm composed of the first pattern layer to the fourth pattern layer by multi-color overprinting at a coating amount of 0.75 g / m ^2. A sheet was produced.
The amount of ink applied was determined by measuring the mass before and after ink application.

(2) Production of decorative molded product As shown in FIG. 5, the third impression cylinder 23 and the activator of the transfer sheet 10 obtained in the above (1) are arranged so that the printing layer 2 faces the activator supply roll 24 side. The activator 1 supplied between the supply rolls 24 and prepared in Production Example 1 was applied at a coating amount of 4 g / m ² by the gravure coating method. After being conveyed at room temperature for 1 minute, the transfer sheet 10 is supplied so that the softened printing layer 4 side comes into contact with the surface of the blanket 5 wound around the blanket cylinder 20, and the first impression cylinder 21 and the blanket cylinder 20 The softened printing layer 4 was continuously transferred onto the blanket 5 by pressing between them. Next, an ABS resin sheet that is the printing object 6 is supplied between the blanket cylinder 20 and the second impression cylinder 22 and pressed, and the softened printing layer 4 on the blanket 5 is replaced with the ABS resin that is the printing object 6. It was continuously transferred to the sheet made.
Next, the obtained article to be transferred was dried to obtain a decorative sheet to which the printing layer was transferred.
Next, an acrylic resin layer having a thickness of 10 μm was formed as a transparent protective layer on the surface of the printing layer of the decorative sheet.
In addition, as for the application amount of the activator, an ABS sheet having a thickness of 200 × 400 mm is prepared separately, and when the activator is applied under the same conditions as in each example, the mass of the sheet before application and 10 seconds after application Was calculated based on the difference in mass.
The results evaluated by the above method are shown in Table 1.

Examples 2-4
Except having used the activator and ink which are shown in Table 1, the transfer sheet was created like Example 1 and the decorating sheet was obtained using it.
The results evaluated by the above method are shown in Table 1.

Ink 1: (manufactured by DIC Graphics, “GT color”, vehicle: cellulosic resin, weight average molecular weight: 1 million)
Ink 2: (manufactured by DIC Graphics, “KLCF”, vehicle: cellulose resin, weight average molecular weight: 5 million)
Ink 3: (manufactured by DIC Graphics, “MA”, vehicle: cellulosic resin, weight average molecular weight: 5 million)

  According to the present invention, it is possible to perform multicolor printing with a small number of steps using a compact printing apparatus on a substrate, and it is possible to perform offset printing with stable printing accuracy. The decorative molded product produced by the transfer printing method of the present invention can be suitably used for automobile interior materials, building materials, furniture, electrical product housings, and the like.

1: base film 2: printing layer 3: activator 4: softened printing layer 5: blanket 6: substrate 10: transfer sheet 20: blanket cylinder 21: first impression cylinder 22: second impression cylinder 23: third Impression cylinder 24: Activator supply roll 25: Doctor blade

Claims (7)

Using a transfer sheet formed by laminating at least multicolor printing layer on a base film, coating an active agent onto (A) the printed layer, the step of softening at least a portion of the printing layer, (B) the the transfer sheet pressed between the first impression cylinder and the blanket cylinder, the printing substrate is pressed onto the blanket by softened step Nikki copy to the print layer continuously on the blanket, and (C) pushing means, offset printing process which comprises the step (B) by the print layer taken copy on the blanket else taking continuously copies on the substrate subjected to decoration to the substrate step. The printed material is in the form of a sheet or a film, and the pressing means is a second impression cylinder. In the step (C), the printed material is pressurized between the blanket cylinder and the second impression cylinder and softened. The offset printing method according to claim 1, wherein the printed layer is continuously copied onto a substrate.   The offset printing method according to claim 1, wherein the printing layer is formed from an ink containing a cellulose resin as a vehicle.   The said activator contains 1-20 mass% of phthalic acid esters, 60-90 mass% of alcohols, 0-20 mass% of esters except phthalic acid esters, and 1-20 mass% of ketones. 4. The offset printing method according to any one of 3. In addition to the above (A) ~ (C) step, further (D) to the transferred the printing layer, offset printing method according to claim 1, comprising the step of forming a protective film.  The offset printing method according to any one of claims 1 to 5, wherein the base film is formed using at least one selected from polyolefin resins and polyester resins. A method for producing a decorative molded product, wherein the offset printing method according to any one of claims 1 to 6 is used.

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