JP2000043435A - Printed matter and method for printing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To rapidly complete printing of only a necessary portion of a base material without necessity of the step of vaporizing water by printing an ultraviolet curable ink having a specific composition on the material, curing the ink with an ultraviolet ray to form a receptive layer, and then printing the layer by thermal transferring. SOLUTION: A ultraviolet curable ink containing a liquid-like water soluble monomer, a monomer soluble hydrophobic polymer and a filler having a mean particle size of a range of 0.1 to 30 μm is printed on a base material, the ink is cured with a ultraviolet ray to form a receptive layer, and the layer is printed by thermal transferring to obtain the printer matter. The printing by the thermal transfer means all general methods for transferring heat fusible solid ink to the material to be transferred by heat fusing the ink. The liquid-like water soluble monomer is polymerizable monomer dissolved at an arbitrary ratio with water at the time of the ambient temperature. As the hydrophilic polymer, for example, an alkyl(meth)acrylate(co)polymer is used. As the filler, silica or the like is used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed material and a printing method for performing printing by thermal transfer on a base material via a receiving layer.

[0002]

2. Description of the Related Art Conventionally, when printing on a base material such as paper, film, and board, ink absorption is accelerated, bleeding is reduced,
Further, in order to improve the adhesiveness between the ink and the substrate, a substrate is coated with a receiving layer. As the coating agent for forming the receiving layer, a material obtained by dissolving a water-soluble polymer in an aqueous medium and further adding silica, alumina, aluminum hydroxide, or the like as a filler is used.

[0003]

However, these coating agents are generally coated on the entire surface of the base material and are coated relatively thickly. Therefore, the coating agent is subjected to a long process to evaporate water in the coating agent. Is performed. Therefore, when forming the receiving layer, it is suitable not only for the case where the entire surface of the base material is coated and printed on the entire surface, but also for the case where only the required portion of the base material is printed, and without the need for a step of evaporating water. There has been a demand for a printed material and a printing method capable of completing printing quickly. Accordingly, an object of the present invention is to provide a receiving layer that satisfies such demands, a printed matter obtained by performing thermal transfer printing on the receiving layer, and a printing method.

[0004]

According to the present invention, there is provided an ultraviolet-ray comprising a base material containing a liquid water-soluble monomer, a hydrophobic polymer soluble in the monomer, and a filler having an average particle diameter in the range of 0.1 μm to 30 μm. The present invention provides a printed material obtained by printing a curable ink and curing it with ultraviolet light to form a receiving layer, and further performing printing by thermal transfer on the receiving layer.

Further, the present invention provides an ultraviolet curable ink comprising a liquid water-soluble monomer, a hydrophobic polymer soluble in the monomer, and a filler having an average particle diameter in the range of 0.1 μm to 30 μm. The present invention provides a printing method characterized by printing, curing by ultraviolet rays to form a receiving layer, and further performing printing by thermal transfer on the receiving layer.

[0006] In the present invention, printing by thermal transfer means a general method of transferring a heat-fusible solid ink to a substrate to be printed by heat melting, and more specifically, an electrophotographic monochrome hard disk using toner. Copying, color hard copy, printing with a printer, or printing, in which the solid printing ink film applied on the supporter film is melted with the help of heat at the time of transfer and is fixed and welded to the object to be transferred. .

[0007] In the present invention, the liquid water-soluble monomer is a polymerizable monomer that can be dissolved in water at an arbitrary ratio at normal temperature. Examples include (meth) acrylates of polyhydric alcohols, (meth) acrylates of N-alkylamino alcohols, polyethylene glycol (meth) acrylates,
-Alkyl (meth) acrylamide, vinyl ether of polyhydric alcohol, and the like.

More specific examples include butanediol monoacrylate, 2-hydroxyethyl acrylate, N, N-diethylaminoethyl methacrylate,
N, N-dimethylaminoethyl acrylate, N, N-dimethylaminoethyl methacrylate, N, N-dimethylacrylamide, acryloylmorpholine, 2-hydroxyethyl vinyl ether and the like can be mentioned.
It is also possible to use mixtures of these monomers.

Further, a water-insoluble monomer of 80 parts by weight or less can be mixed with 100 parts by weight of these water-soluble monomers. Further, a polymerizable oligomer can be used in combination.

Examples of the water-insoluble monomer include phenoxyethyl acrylate, isobornyl acrylate, hexanediol diacrylate and the like.

Next, the polymer which is an essential component of the ink which is a component of the present invention will be described. In selecting this polymer, two criteria apply. The first criterion is that the polymer is soluble in the aforementioned water-soluble monomer or a mixture of 100 parts by weight of the water-soluble monomer and up to 80 parts by weight of the water-insoluble monomer. The second criterion is that when a polymer is formed into a film and immersed in water at 25 ° C. for 2 hours, 10 g or more of water is absorbed and swelled per 100 g of polymer, or the polymer itself is substantially dissolved in water. That is not to do.

Among the polymers satisfying the above two criteria, examples of the hydrophobic polymer include an alkyl (meth) acrylate (co) polymer, a vinyl chloride-vinyl acetate copolymer, a polyester, a cellulose acetate, and a cellulose propionate. , Cellulose acetate butyrate, nitrocellulose, butyral resin and the like. Particularly preferred examples include cellulose derivatives such as cellulose acetate, cellulose propionate and cellulose acetate butyrate.

In the ink of the present invention, the amount of the polymer added is 3 to 8 per 100 parts by weight of the liquid water-soluble monomer.
It is preferably 0 parts by weight. More preferably 5-
60 parts by weight. If the addition amount is below this range, the toner and the thermal transfer printing ink film when the receiving layer of the obtained printed material is printed by thermal transfer may have poor fixation / weldability and poor water resistance. Further, the storage stability and printability of the ink containing no polymer are extremely poor. On the other hand, if the amount of the polymer is more than the above range, the transferability of the toner or the thermal transfer printing ink film becomes poor, and it is difficult to obtain a clear image.

As for the polymer, in addition to the above-mentioned hydrophobic polymer, a hydrophilic polymer (water-soluble polymer)
It is also possible to use together. That is, it is generally preferable to use not more than 60 parts by weight of the water-soluble polymer per 100 parts by weight of the hydrophobic polymer without any problem.

The ultraviolet-curable ink of the present invention contains a filler. Examples of the filler include silica, talc, clay, zeolite, calcium carbonate, calcium silicate, magnesium carbonate, barium sulfate, mica, synthetic mica, and diatomaceous earth. , Aluminum hydroxide, alumina, titanium oxide, and other generally known fillers. Among these, silica, synthetic mica, aluminum hydroxide, and alumina are particularly preferred from the viewpoints of improving acceptability, water resistance, whiteness, and the like.

The average particle size of the filler used in the present invention is preferably from 0.1 to 30 μm, and more preferably from 0.2 to 15 μm.

The ultraviolet curable ink, which is a component of the present invention, contains a liquid water-soluble monomer and a filler in addition to a hydrophobic polymer. 15 per 100 parts by weight
３００300 parts by weight are used. More preferably, the amount of the filler is 30 parts per 100 parts by weight of the liquid water-soluble monomer.
To 150 parts by weight, more preferably 60 to 120 parts by weight.
Used by weight. If the amount of the filler exceeds 300 parts by weight, the printing characteristics of the ink may be deteriorated.
If the amount is less than the weight part, the receiving performance may be reduced.

In the present invention, as the filler other than the above, an organic filler such as a powder of natural fiber powder or a crosslinked, monomer-insoluble water-absorbent resin powder may be used as necessary. Examples of natural fiber powders include cellulose fiber powders such as pulp, cotton, and hemp, polypeptide fiber powders such as wool, silk, and collagen fibers, and other fiber powders. Also, a mixture of these powders can be suitably used.
The average particle size of these natural fiber powders is preferably 1 to 20 μm.
m, and more preferably 3 to 15 μm. If the average particle diameter is 20 μm or more or 1 μm or less, printability and print acceptability may be poor.

Examples of other additives that can be used in combination include oligoester acrylates, oligomers of acrylic acid esters having a polymerizable double bond, and oligomers such as oligourethane acrylate.

For more detailed examples of oligomers and monomers, see Kiyoshi Kato, “Ultraviolet Curing System”, published by Sogo Gijutsu Center (February 28, 1989).
It is shown on page 33.

In the present invention, ultraviolet rays are used to promote the polymerization of the monomer. In this case, a photopolymerization initiator for initiating the polymerization is generally used in combination. Examples of the photopolymerization initiator are not particularly limited as long as radicals or other active species generated by light react with the polymerizable double bond in the above-mentioned monomer or oligomer to induce a polymerization reaction.
Examples include benzoin ethyl ether, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1-
(4- (methylthio) phenyl) -2-morpholinopropanone-1, bisacylphosphine oxide and the like can be mentioned. These photopolymerization initiators may be used alone or in combination.
More than one species can be used in combination.

Further, examples of the photopolymerization initiator include light described in Kiyomi Kato, “Ultraviolet Curing System”, published by Sogo Gijutsu Center (February 28, 1989), pp. 65-148. Examples thereof include a polymerization initiator. The use amount of these photopolymerization initiators is not particularly limited, but is generally about 1 to 10% by weight, preferably 2 to 5% by weight.
It is used in the order of% by weight.

Further, the ink which is a component of the present invention may contain a leveling agent, an antifoaming agent, a dye, a pigment and the like, if necessary.

The ink of the present invention can be generally printed by any printing method such as gravure printing, flexographic printing, and screen printing. However, in order to give a sufficient receiving performance to the printed layer, the thickness of the printed layer is preferably 5 to 5. It is desirable that the thickness be about 100 μm, more preferably about 10 to 40 μm.

Therefore, the most preferable example is screen printing in which the thickness of the printing layer is easily adjusted to the above range. Further, the ink of the present invention can be used after being coated by a coating method.

In any case, after printing or coating, the ink of the present invention is cured by irradiating ultraviolet rays acting on a photopolymerization initiator to give a receptive printing layer.

The printing layer thus obtained is rich in receptivity and provides a preferable receiving layer. In addition, this receiving layer can be easily formed not only on paper but also on a base material such as a plastic film, a plastic plate, or a metal plate.

When printing is performed on the receiving layer by thermal transfer, the printed toner and thermal transfer printing ink film are quickly and reliably transferred to the receiving layer, so that printing by thermal transfer can be performed with almost no transfer failure. it can.

In particular, using the present invention, a receiving layer is provided on the back surface of a compact disc or the like as an optical information medium, and the use and characteristics of the compact disc can be easily recorded thereon by printing by thermal transfer. It is extremely useful because it can be used.

[0030]

EXAMPLES Hereinafter, the performance of the receiving layer printed on the base material will be described with reference to examples, and the adhesion of the thermal transfer ink and the sharpness of the image when thermal transfer printing is performed on the receiving layer. It was judged in degrees.

Examples 1 to 4 Various raw materials were blended at the weight ratios shown in Table 1 below, and these were dispersed using a stirrer to prepare various photocurable receptive inks.

[0032]

[Table 1] The ultraviolet curable receptive ink thus prepared was screen-printed on the treated PET film using a 300-mesh screen, irradiated with ultraviolet rays, and cured to form a 25 μm thick receiving layer.

Next, using a thermal transfer color printer, printing was performed on the receiving layer using a thermal transfer ribbon, and thermal transfer printing performance was examined. Table 2 shows the results of examining the transferability of the thermal transfer ribbon and the sharpness of the image.

In the evaluations in Table 2, ◎ indicates very good, 〇 indicates good, △ indicates slightly poor, and × indicates bad.

[0035]

[Table 2]

As described above, according to the printed matter and the printing method of the present invention, the receiving layer can be printed not only on the entire surface of the base material but also only on a necessary portion, and without a step of evaporating water. Printing can be completed quickly.
Further, a high quality thermal transfer printing layer can be provided on the receiving layer.

Claims (2)

[Claims] 1. A liquid water-soluble monomer, a monomer-soluble hydrophobic polymer and an average particle size of 0.1 μm
A printed matter obtained by printing an ultraviolet-curable ink containing a filler in the range of from 30 to 30 μm, curing the ink with ultraviolet rays to form a receiving layer, and further performing thermal transfer printing on the receiving layer. 2. A method according to claim 1, wherein a liquid water-soluble monomer, a monomer-soluble hydrophobic polymer and an average particle size of 0.1 μm are formed on the substrate.
A printing method, comprising printing an ultraviolet-curable ink containing a filler in the range of 30 μm to 30 μm, curing with an ultraviolet ray to form a receiving layer, and further performing printing by thermal transfer on the receiving layer.