JP6562145B1 - Ultraviolet laser marking composition, printed matter and laminate using the same - Google Patents

Abstract

An ultraviolet laser marking composition that can be suitably used for packaging materials, particularly food packaging materials, and simultaneously achieves excellent laser printing visibility (printing density) and transparency of a printed layer, and printed matter using the same A laminate is provided. A metal containing at least one binder resin selected from polyurethane resin, acrylic resin, vinyl chloride copolymer resin and chlorinated polyolefin resin, and selected from zinc, titanium, cerium, antimony, tin, iron and zirconium. Ultraviolet laser marking composition containing at least one metal oxide (A) derived from [Selection figure] None

Description

  The present invention relates to an ultraviolet laser marking composition. Moreover, it is related with the printed matter and laminated body using the same.

  More specifically, the present invention relates to a laser marking composition capable of providing a laminate having excellent visibility and transparency by printing with an ultraviolet laser.

For packaging materials, containers, labels, etc. used for food and medicine packages, marking the product production lot number, production location, production date, expiry date, expiration date, product characteristics, etc. Say) is needed. Particularly in recent years, the need for a wide variety of printing has increased from the viewpoint of communication with consumers in addition to security and traceability of these products (manufacturing date, manufacturing location and other history information regarding production).
Conventionally, a hot stamp printing method, an ink jet printing method, a thermal transfer ribbon method, or the like has been used as a method for performing such printing. However, in such a printing method, since a printed layer made of ink is printed on the surface of the object, there is a risk of peeling due to impact or rubbing of the printed layer, damage due to alcohol or oil, and erasure. was there.

  In recent years, as a marking method that can solve this, a method of marking by irradiating a laser beam has been proposed. The laser marking method is a printing method that does not cause ink to adhere, but causes alteration or deformation (engraving) of the material of the target part with laser light, so there is low concern about peeling and erasing, and excellent tamper resistance. Since it prints in a non-contact manner, there are features such as no unnecessary influence on the material, high-speed printing, excellent variable printing, and no choice of the surface shape of the printing surface. In addition, as the type of laser light, since it has printability on a wide range of target materials such as resin, metal, paper, glass, and the irradiation device is relatively inexpensive, an infrared laser (for example, a laser wavelength of 1064 nm, A fundamental wave Nd: YAG laser, a fundamental wave YVO4 laser, or a carbon dioxide laser with a laser wavelength of 10640 nm has been mainly used.

  Further, in recent years, ultraviolet lasers (for example, third harmonic Nd: YAG laser, third harmonic YVO4 laser, etc., having a laser wavelength of 355 nm) have been widely used for industrial use, and the need for marking materials compatible with ultraviolet lasers. Is growing.

As an example of the laser marking method, Patent Document 1 discloses ultraviolet laser marking on a molded article made of a polyacetal resin composition containing a photoactive filler. However, this method causes alteration or deformation (engraving) on the material surface of the molded product itself, so that damage (irregularities) of the laser irradiation location is unavoidable, and it is difficult to apply to packaging materials from the viewpoint of protecting the contents. is there. Furthermore, polyacetal resin has a concern about adhesion and the like when used for a laminate composed of various materials. Furthermore, since the composition is colored, it is difficult to utilize it for packaging materials that require transparency.
Patent Document 2 introduces laser marking on a laser marking laminate comprising a plastic film, a printing ink film layer, and a substrate. Although the printing visibility is excellent, since the printing layer is colored in this method, its use for packaging materials that require transparency is limited. Furthermore, an infrared laser is mentioned as a suitable laser, and implementation with an ultraviolet laser is not mentioned.

Therefore, a laser marking composition used for a packaging material, which can obtain a laminate excellent in visibility and transparency in ultraviolet laser printing, has not yet been developed.
Japanese Patent Laid-Open No. 10-16390 JP 2009-137261 A

  The present invention relates to an ultraviolet laser marking composition that can be suitably used for packaging materials, particularly food packaging materials, and simultaneously achieves excellent laser printing visibility (print density) and transparency of the printed layer, and printed matter using the same. It aims at providing a laminated body.

  As a result of intensive studies in view of the above-mentioned problems, the present inventors have found that the problems can be solved by using the ultraviolet laser marking composition described below, a printed material using the composition, and a laminate. It came to make.

That is, the present invention is an ultraviolet laser marking composition comprising a binder resin and a metal oxide (A),
The binder resin contains a polyurethane resin and a vinyl chloride copolymer resin in a mass ratio of 95: 5 to 40:60 ,
It is related with the ultraviolet laser marking composition whose metal oxide (A) contains a zinc oxide and whose average particle diameter of a metal oxide (A) is 5-400 nm.

Moreover, this invention relates to the said ultraviolet laser marking composition whose primary particle diameter of the said metal oxide (A) is 5-100 nm .

  Moreover, this invention relates to the printed matter which has the printing layer which consists of the said ultraviolet laser marking composition on the base material 1. FIG.

Moreover, this invention relates to the said printed matter whose total light transmittance of a printing layer is 50% or more .
Moreover, this invention relates to the laminated body which has the base material 2 further on the printing layer of the said printed matter.
Moreover, this invention relates to the manufacturing method of the ultraviolet laser printed matter which prints by irradiating an ultraviolet laser with respect to the printed matter or laminated body which comprises the printing layer which consists of the said ultraviolet laser marking composition.

  According to the present invention, an ultraviolet laser marking composition that can be suitably used for packaging materials, particularly food packaging materials, and simultaneously achieves excellent laser printing visibility (print density) and transparency of the printed layer, and printed matter using the same. And was able to provide a laminate.

  Embodiments of the present invention will be described in detail below, but the matters described below are examples (representative examples) of the embodiments of the present invention, and the present invention is limited to these contents as long as the gist thereof is not exceeded. Not.

  In the following description, the laser marking composition may be referred to as “composition” or “ink”, but both are synonymous.

  Further, in the following description, the printed layer made of the above composition may be expressed as “ink layer” or “ink film”, which are synonymous.

  In the following description, laser marking may be simply abbreviated as “marking” or “printing”, but it is synonymous.

<Ultraviolet laser marking composition>
The present invention provides at least one resin selected from polyurethane resin, acrylic resin, vinyl chloride copolymer resin and chlorinated polyolefin resin as a binder resin, and a metal selected from zinc, titanium, cerium, antimony, tin, iron and zirconium. It is an ultraviolet laser marking composition which uses at least 1 sort (s) among the metal oxide (A) derived from this as an essential component. By using the binder resin and the metal oxide (A), it is possible to provide a laser marking composition that can be applied to an ultraviolet laser.

<Binder resin>
In the present invention, by containing at least one resin selected from polyurethane resin, acrylic resin, vinyl chloride copolymer resin and chlorinated polyolefin resin as a binder resin, the metal oxide (A) can be well dispersed, Excellent ink production suitability, ink aging stability, and high transparency can be obtained in printed matter using the ink. Furthermore, it has excellent adhesion to a biaxially stretched polypropylene film, biaxially stretched polyester film, biaxially stretched polyamide film and other substrates, and a good laminate strength can be obtained in a laminate obtained by laminating.
In particular, in terms of adhesion to the film, laminate strength, and the like, it is preferable to include a polyurethane resin and a vinyl chloride copolymer resin, and it is preferable to include 50% by mass to 100% by mass in the total amount of the binder resin. In addition, it is preferable to contain a polyurethane resin and a vinyl chloride copolymer resin by mass ratio 95: 5 to 40:60.

  The binder resin content in the ultraviolet laser marking composition of the present invention is preferably in the range of 4 to 25 parts by mass in 100 parts by mass of the ink. From the viewpoint of ink film adhesion and ink production suitability, it is more preferably in the range of 6 to 18 parts by mass.

<Polyurethane resin>
The polyurethane resin preferably has a weight average molecular weight of 10,000 to 100,000, preferably has a glass transition temperature of −60 ° C. to 0 ° C., and further has a storage elastic modulus at 40 ° C. in dynamic viscoelasticity measurement. Is preferably 1 to 100 MPa.
In addition, in this specification, a glass transition temperature is measured with a differential scanning calorimeter (DSC) and represents an inflection point in a temperature range where the glass transition occurs.

  The polyurethane resin preferably has an amine value and / or a hydroxyl value, and the amine value is preferably 1 to 20 mgKOH / g. The hydroxyl value is preferably 1 to 20 mgKOH / g. In addition, the polyurethane resin of this invention may have a urea bond, may not have a urea bond, and may use 2 or more types together.

There is no restriction | limiting in particular in the polyurethane resin of this invention, For example, it manufactures suitably by the well-known method described in Unexamined-Japanese-Patent No. 2013-213109 or Unexamined-Japanese-Patent No. 2005-298618.
Although not limited by the production method, for example, a polyurethane resin obtained by subjecting a polyurethane resin comprising a polyol and a polyisocyanate, a urethane prepolymer of a terminal isocyanate comprising a polyol and a polyisocyanate, and a chain extension reaction with an amine compound. Resins are preferred.

  Examples of the polyol include polyester polyol, polyether polyol, polycaprolactone diol, polycarbonate polyol, polyolefin polyol, castor oil polyol, hydrogenated castor oil polyol, dimer diol, and hydrogenated dimer diol. It is preferable to use a polyester polyol, and it is more preferable to use a polyether polyol and a polyester polyol in combination.

Examples of the polyether polyol include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polytrimethylene glycol, and copolymer polyether polyols composed of a combination of two or more of these. Among them, polytetramethylene glycol, polypropylene glycol, and polyethylene glycol are preferable, and the number average molecular weight is preferably 500 to 10,000. In addition, the number average molecular weight of the polyol described in this specification is based on the valence (average number) of the hydroxyl group of one polyol molecule and the hydroxyl value (1 mol of hydroxyl group mole value converted to potassium hydroxide) in 1 g of polyol solids. It is calculated and is obtained by (Equation 1).
(Formula 1) Number average molecular weight of polyol = 1000 × 56.1 × hydroxyl number of hydroxyl group / hydroxyl value

  As said polyester polyol, the condensate etc. which are obtained by esterification reaction of a dibasic acid and diol are mentioned, for example. Dibasic acids include adipic acid, phthalic anhydride, isophthalic acid, terephthalic acid, maleic acid, fumaric acid, succinic acid, oxalic acid, malonic acid, pimelic acid, azelaic acid, sebacic acid, suberic acid, glutaric acid, 1 , 4-cyclohexyldicarboxylic acid, dimer acid, hydrogenated dimer acid and the like. Examples of the diol include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 1,6-hexanediol, and 1,8-octanediol. 1,9-nonanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, 2-methyl-1,3-propanediol, 3,3,5-trimethylpentanediol, 2,4-diethyl- 1,5-pentanediol, 1,12-octadecanediol, 1,2-alkanediol, 1,3-alkanediol, 1-monoglyceride, 2-monoglyceride, 1-monoglycerin ether, 2-monoglycerin ether, dimer diol , Hydrogenated dimer diol, etc. It is below. As the dibasic acid, sebacic acid and adipic acid are particularly preferable. Moreover, the polyvalent carboxylic acid which has 3 or more of carboxyl groups can also be used together.

As the diol constituting the polyester polyol, a diol having an alkyl group is preferable. The diol having an alkyl group means a diol having a structure in which at least one hydrogen atom of an alkylene group contained in the diol is substituted with an alkyl group, and includes propylene glycol, 1,3-butanediol, 2-methyl-1 , 3-propanediol, neopentyl glycol, 1,4-pentanediol, 3-methyl-1,5-pentanediol, 2,5-hexanediol, 2-methyl-1,4-pentanediol, 2,4- Diethyl-1,5-pentanediol, 2-butyl-2-ethyl-1,3-propanediol, 2-methyl-1,8-octanediol, 2,2,4-trimethyl-1,3-pentanediol, And 2,2,4-trimethyl-1,6-hexanediol and the like. These are particularly preferable because they exhibit strong adhesion to various substrates described later. Moreover, the polyol which has 3 or more of hydroxyl groups can also be used together.
These polyester polyols can be used alone or in admixture of two or more.

  The number average molecular weight of the polyester polyol is preferably 500 to 10,000. The number average molecular weight is determined by the above (Formula 1). The acid value of the polyester polyol used in the present invention is preferably 1.0 mgKOH / g or less, and more preferably 0.5 mgKOH / g or less.

  The polyurethane resin preferably contains a structural unit derived from the above polyether polyol, and the content of the structural unit is preferably 0.5 to 30 parts by mass, more preferably 1 to 100 parts by mass in 100 parts by mass of the polyurethane resin. 25 parts by mass. In the present specification, the structural unit derived from the polyether polyol refers to the structure of the polyether polyol, which is a raw material of the polyurethane resin, from the oxygen atom of the hydroxyl group at one end to the oxygen atom of the hydroxyl group at the other end, It is a value calculated from the blending amount of the polyether polyol.

  The polyurethane resin preferably contains a structural unit derived from the polyester polyol, and the content of the structural unit is preferably 30 to 75 parts by mass, more preferably 40 to 75 parts by mass in 100 parts by mass of the polyurethane resin. More preferably, it is 45 to 75 parts by mass. In the present specification, the structural unit derived from the polyester polyol means the structure from the oxygen atom of the hydroxyl group at one end to the oxygen atom of the hydroxyl group at the other end of the polyester polyol that is a raw material of the polyurethane resin. It is the value computed from the compounding quantity of.

  The polyurethane resin preferably contains both the structural unit derived from the polyester polyol and the structural unit derived from the polyether polyol, and the mass ratio of the structural unit derived from the polyester polyol and the structural unit derived from the polyether polyol (polyester / polyester). Ether) is preferably contained at 55/45 to 99/1, more preferably contained at a mass ratio of 60/40 to 90/10, and contained at a mass ratio of 70/30 to 90/10. Further preferred. This is because the adhesion can be further improved with respect to various substrates described later.

  In addition, the structural unit derived from the polyester polyol and the structural unit derived from the polyether polyol are in total, preferably 30 to 85 parts by mass, more preferably 45 to 85 parts by mass in the total mass of the polyurethane resin.

Examples of the polyisocyanate include various known aromatic diisocyanates, aliphatic diisocyanates, and alicyclic diisocyanates that are generally used in the production of polyurethane resins.
Examples of aromatic diisocyanates include 1,5-naphthylene diisocyanate, 4,4′-diphenylmethane diisocyanate (MDI), 4,4′-diphenyldimethylmethane diisocyanate, 4,4′-dibenzyl isocyanate, and 1,3-phenylene. Diisocyanate, 1,4-phenylene diisocyanate, tolylene diisocyanate, xylylene diisocyanate, m-tetramethylxylylene diisocyanate and the like can be mentioned.
Examples of the aliphatic diisocyanate include methylene diisocyanate, ethylene diisocyanate, hexamethylene diisocyanate, isopropylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, and lysine diisocyanate. Examples of the alicyclic diisocyanate include cyclohexane-1 , 4-diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4′-diisocyanate, 1,3-bis (isocyanatemethyl) cyclohexane, methylcyclohexane diisocyanate, norbornane diisocyanate, and the carboxyl group of dimer acid is isocyanate Examples include dimerized isocyanate converted into a group.
These may be trimers to form an isocyanurate ring structure. These polyisocyanates can be used alone or in admixture of two or more. Of these, tolylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, hexamethylene diisocyanate, isocyanurate of hexamethylene diisocyanate and the like are preferable.

The amine compound includes a polyamine compound for chain extension of the urethane prepolymer. In one embodiment, the amine compound may include an amine compound that serves as a polymerization terminator, if necessary, in addition to the polyamine compound.
The polyamine compound that serves as a chain extender is not limited to the following, but preferably has a molecular weight of 500 or less, and examples include diamine-based and polyfunctional amine-based compounds, such as ethylenediamine, propylenediamine, hexamethylenediamine, and pentane. In addition to diamine chain extenders such as methylenediamine, isophoronediamine, dicyclohexylmethane-4,4′-diamine, p-phenylenediamine, 2-hydroxyethylethylenediamine, 2-hydroxyethylpropyldiamine, 2-hydroxyethylpropylenediamine, Di-2-hydroxyethylethylenediamine, di-2-hydroxyethylenediamine, di-2-hydroxyethylpropylenediamine, 2-hydroxypyrroleethylenediamine, di-2-hydroxypyrroleethylenediamine A diamine chain extender having a hydroxyl group such as di-2-hydroxypropylethylenediamine can also be used. These chain extenders can be used alone or in admixture of two or more. If necessary, a trifunctional or higher polyfunctional amine chain extender can also be used. Specifically, diethylenetriamine, iminobispropylamine: (IBPA, 3,3′-diaminodipropylamine), triethylenetetramine, N- (3-aminopropyl) butane-1,4-diamine: (spermidine), Examples include 6,6-iminodihexylamine, 3,7-diazanonan-1,9-diamine, and N, N′-bis (3-aminopropyl) ethylenediamine. Of these, isophoronediamine, hexamethylenediamine, and iminobispropylamine are preferable.

  Examples of the amine compound that serves as a polymerization terminator include monovalent amine compounds. The monovalent amine compound may be a primary amine or a secondary amine. The monovalent amine compound functions as a polymerization terminator for the purpose of stopping the excessive reaction. Examples of such compounds include dialkylamines such as di-n-butylamine and amino alcohols such as 2-ethanolamine.

  In the following description, (meth) acryl and (meth) acrylate mean both methacryl and acryl, and methacrylate and acrylate.

<Acrylic resin>
The above acrylic resin refers to a resin obtained by radical polymerization of an acrylic monomer, which can be produced by a conventionally known method, and the production method is not particularly limited. The acrylic resin preferably has an acid value in the range of 0.5 to 50 mgKOH / g, preferably in the range of 2 to 40 mgKOH / g, from the viewpoint of blocking resistance of the resulting ink and ink production suitability. More preferably, it is 2-30 mgKOH / g. For the same reason, the weight average molecular weight is preferably in the range of 5,000 to 200,000, and more preferably in the range of 10,000 to 100,000. The glass transition temperature is preferably 20 to 120 ° C, more preferably 40 to 110 ° C, and further preferably 40 to 105 ° C.
For example, (meth) acrylic acid alkyl ester is preferable as the acrylic monomer, and the alkyl group preferably has 1 to 20 carbon atoms. For example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, cyclohexyl (meth) acrylate 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, tetradecyl (meth) acrylate, hexadecyl (meth) acrylate, (meth) acrylic acid Examples include octadecyl. The alkyl group may further have a benzene ring structure. These can be used alone or in combination of two or more.

The acrylic monomer preferably has a hydroxyl group. Examples thereof include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, and (meth) acrylic acid 2. (Meth) acrylic acid such as hydroxybutyl, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate Hydroxyalkyl esters, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, glycol mono (meth) acrylate such as 1,4-cyclohexanedimethanol mono (meth) acrylate, caprolactone modified (meth) Acrylate and hydroxyethyl acrylamide.
The acrylic resin is preferably an acrylic resin having a structural unit derived from methyl methacrylate, preferably 10 to 95% by mass, and preferably 30 to 95% by mass of the structural unit in the total mass of the acrylic resin. The content is preferably 40 to 95% by mass, and more preferably. The acrylic resin preferably has a hydroxyl group.

<Vinyl chloride copolymer resin>
The vinyl chloride copolymer resin of the present invention is not particularly limited as long as it contains a structural unit derived from vinyl chloride and a structural unit derived from other monomers. Of these, vinyl chloride-vinyl acetate copolymer resin and vinyl chloride-acrylic copolymer resin are preferable.

<Vinyl chloride-vinyl acetate copolymer resin>
The vinyl chloride-vinyl acetate copolymer resin is a copolymer of vinyl chloride and vinyl acetate, and the molecular weight is preferably 5,000 to 100,000 in terms of weight average molecular weight, and 20,000 to 70,000. Is more preferable. The structure derived from the vinyl acetate monomer in 100 parts by mass of the vinyl chloride-vinyl acetate copolymer resin is preferably 1 to 30 parts by mass, and the structure derived from the vinyl chloride monomer is preferably 70 to 95 parts by mass. In this case, solubility in an organic solvent is improved, and adhesion to a substrate, film properties, laminate strength, and the like are improved.
Moreover, since the solubility to an organic solvent improves, what contains the hydroxyl group derived from vinyl alcohol by a saponification reaction or copolymerization is still more preferable, and it is preferable that it is 20-200 mgKOH / g as a hydroxyl value. The glass transition temperature is preferably 50 ° C to 90 ° C.

<Vinyl chloride-acrylic copolymer resin>
Vinyl chloride-acrylic copolymer resin is a copolymer resin mainly composed of vinyl chloride monomer and acrylic monomer. As the acrylic monomer, (meth) acrylic acid improves adhesion to substrates and solubility in organic solvents. It is preferable to include a hydroxyalkyl ester. The acrylic monomer may be incorporated into the main chain of polyvinyl chloride in a block or random manner, or may be grafted to the side chain of polyvinyl chloride. The vinyl chloride-acrylic copolymer resin preferably has a weight average molecular weight of 10,000 to 100,000, more preferably 30,000 to 70,000.

Moreover, it is preferable that the structure derived from the vinyl chloride monomer in vinyl chloride-acrylic copolymer resin is 70-95 mass parts in 100 mass parts of vinyl chloride-acrylic copolymer resin solid content. In this case, solubility in an organic solvent is improved, and adhesion to a substrate, film properties, laminate strength, and the like are improved.
In addition, the thing similar to the case of the said acrylic resin is mentioned suitably as an acrylic monomer used for a vinyl chloride-acrylic copolymer resin, and may be the same or different. Among them, 2-hydroxyethyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and 2-hydroxypropyl acrylate are more preferable because they improve solubility in organic solvents. These can be used alone or in combination of two or more.

<Chlorinated polyolefin resin>
The chlorinated polyolefin resin in the present invention has a chlorine content of preferably 25 to 45% by mass and more preferably 26 to 40% by mass because adhesion to a film and laminate strength are improved. Here, the chlorine content in the present invention is the content mass% of chlorine atoms in 100 mass% of the chlorinated polyolefin resin. Further, from the viewpoint of solubility in a mixed solvent such as an ester solvent / alcohol solvent, the weight average molecular weight of the chlorinated polyolefin resin in the present invention is preferably 5,000 to 50,000.
In the present invention, the chlorinated polyolefin resin has a structure in which hydrogen of an α-olefin polymer is substituted with chlorine, and the α-olefin is a carbon-carbon double bond represented by the following general formula (1). The alkene at the α-position, that is, at the end.
General formula (1)

CH ₂ = ^{CH-R 1}

(In the formula, R ¹ is an alkyl group having 1 or more carbon atoms.)
Since the chlorinated polyolefin resin has a flexible alkyl group as a branched structure, the chlorinated polyolefin resin is flexible even at low temperatures and improves the adhesion to the substrate. The α-olefin structure in the chlorinated polyolefin resin is not particularly limited. For example, a resin containing a homopolymer or copolymer of an α-olefin unsaturated hydrocarbon such as polypropylene, poly-1-butene and poly-4-methyl-1-pentene is preferable. Among these, those containing a polypropylene structure (that is, a chlorinated polypropylene structure) are particularly preferable.

  Further, the chlorinated polyolefin resin may be a copolymer resin with other monomers, and there is no particular limitation as long as it is the chlorine content. The copolymerizable monomer is preferably an acrylic monomer, an acidic monomer, a vinyl acetate monomer, a styrene monomer, or the like. Examples of the acrylic monomer include the acrylic monomers described above, and the acidic monomer is maleic acid, maleic anhydride, fumaric acid, citraconic acid, citraconic anhydride, mesaconic acid, itaconic acid, itaconic anhydride, aconitic acid, anhydrous Examples include aconitic acid, hymic anhydride, (meth) acrylic acid, and the like.

(Combination resin)
In the present invention, the binder resin can be used alone or in combination of two or more of the above polyurethane resins, acrylic resins, vinyl chloride copolymer resins and chlorinated polyolefin resins. Depending on the case, resins other than those mentioned above may be used in combination. Examples of the combination resin include cellulose resin, ethylene-vinyl acetate copolymer resin, polyamide resin, polyester resin, alkyd resin, rosin resin, rosin-modified maleic acid resin, cyclized rubber, chlorinated rubber, butyral and the like. The amount of the combined resin used is preferably 1 to 50% by mass in the total mass of the binder resin.

<Metal oxide (A)>
The ultraviolet laser marking composition of the present invention contains a metal oxide (A) derived from a metal selected from zinc, titanium, cerium, antimony, tin, iron and zirconium as a compound capable of laser marking. The metal oxide (A) is a fine particle.

  The average particle diameter of the metal oxide (A) in the present invention is preferably 5 to 400 nm in order to obtain good transparency in the printed layer and laminate, ink production suitability and ink aging stability. It is still more preferable that it is 5-350 nm, and it is still more preferable that it is 10-250 nm. In addition, the average particle diameter in this invention means D50 particle diameter in the measurement by a dynamic light scattering method. For example, it can be measured using MicrotracWaveII-EX150 manufactured by Microtrack Bell. Further, the primary particle diameter is preferably 5 to 100 nm, more preferably 5 to 80 nm, and further preferably 10 to 50 nm. Here, the primary particle diameter is calculated using the specific surface area obtained from the gas adsorption amount by the BET method. Further, the oil absorption is preferably 14 to 33 ml / 100 g, more preferably 17 to 30 ml / 100 g. The oil absorption amount is a value measured according to JISK5101.

  These metal oxides (A) promote the modification and discoloration of the ink film by absorbing an ultraviolet laser of 10 to 400 nm, preferably an ultraviolet laser of 260 to 400 nm, and transparency of the non-printing part. While maintaining the above, excellent visibility is exhibited in the ultraviolet laser printing portion. Since the output of the ultraviolet laser has the effect of obtaining excellent print visibility even at low energy, the laminate using the ultraviolet laser marking composition can suppress damage (irregularities) of the laser irradiation site, and the barrier A packaging material that suppresses deterioration of properties and appearance can be obtained.

Examples of the metal oxide (A) in the present invention include zinc oxide, titanium oxide, cerium oxide, antimony trioxide, antimony pentoxide, tin oxide, iron (II) oxide, iron (III) oxide, and zirconium dioxide. Preferably mentioned.
From the viewpoint of transparency of the printed layer and ink production suitability, it is preferable to contain zinc oxide and / or titanium oxide, more preferably zinc oxide. Moreover, it is preferable that zinc oxide and titanium oxide are contained in the total amount of the metal oxide (A) in a total amount of 50% by mass to 100% by mass.

  The content of the metal oxide (A) in the present invention is preferably 4 to 60 parts by mass in 100 parts by mass of ink in order to obtain good laser printing visibility, ink production suitability and film properties. More preferably, it is -50 mass parts.

<Medium>
The ultraviolet laser marking composition preferably contains an organic solvent or water as a medium, and is preferably an organic solvent-based composition containing an organic solvent as a main component of the medium. Examples of the organic solvent include aromatic organic solvents such as toluene and xylene, ketone organic solvents such as methyl ethyl ketone and methyl isobutyl ketone, ethyl acetate, n-propyl acetate, isopropyl acetate, isobutyl acetate, ester organic solvents, methanol, ethanol, Known solvents such as alcohol-based organic solvents such as n-propanol, isopropanol and n-butanol, and hydrocarbon solvents such as methylcyclohexane can be used, and these are preferably contained as a mixed solvent. Moreover, the aqueous composition which contains water as a main component of a medium may be sufficient, and in this case, water-soluble alcohol etc. can be used in a small amount of 20 mass% or less as needed.

(Additive)
In the present invention, known additives can be appropriately included, and in the production of the ultraviolet laser marking composition, known additives such as dispersants, wetting agents, adhesion aids, leveling agents, An antifoaming agent, an antistatic agent, a trapping agent, an antiblocking agent, a wax component, an isocyanate curing agent, a silane coupling agent, and the like can be used.

(Curing agent)
When applying the laser marking composition of the present invention, a curing agent can be used in combination for the purpose of improving the strength, heat resistance, water resistance, solvent resistance and the like of the printed layer. As the curing agent, isocyanate, oxazoline, carbodiimide, ethyleneimine, and the like can be used. From the viewpoint of film strength and film physical properties, isocyanate-based curing agents are preferred. Of the isocyanate curing agents, those having a functionality of 3 or more are particularly preferred.

<Manufacture of ultraviolet laser marking composition>
Next, an example is demonstrated about the manufacturing process of the ultraviolet laser marking composition of this invention. The binder resin, the metal oxide (A), an organic solvent as a medium, a combination resin as required, and various additives are mixed with stirring in advance, and then charged into a disperser. A well dispersed UV laser marking composition is obtained.
Dispersers include paint conditioner (manufactured by Red Devil), ball mill, sand mill (such as “Dyno mill” manufactured by Shinmaru Enterprises), attritor, pearl mill (such as “DCP mill” manufactured by Eirich), coball mill, homomixer, Examples thereof include a homogenizer (such as “CLEARMIX” manufactured by M Technique Co., Ltd.), a wet jet mill (“GENUS PY” manufactured by Genus, “Nanomizer” manufactured by Nanomizer), and the like. When using media in the disperser, it is preferable to use glass beads, zirconia beads, alumina beads, magnetic beads, styrene beads, or the like.

<Manufacture of printed matter>
The printed matter of the present invention is formed on the substrate 1 by a conventionally known method such as gravure printing, flexographic printing, spray coating, spin coating, die coating, lip coating, knife coating, dip coating, curtain coating, roll coating and the like. After the composition is printed or applied, it is produced by drying appropriately. The thickness of the printing layer or coating layer is preferably 0.1 to 15 μm, and more preferably 0.3 to 3 μm. The production of the printed material is preferably a printing method.

<Substrate 1>
Examples of the substrate 1 used in this embodiment include polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate (PET) and polylactic acid, polystyrene resins such as polycarbonate, polystyrene, AS resin, and ABS resin, nylon, and polyamide. , Polyvinyl chloride, polyvinylidene chloride, cellophane, paper, aluminum, etc., or a film-like substrate made of a composite material thereof. Further, a vapor deposition substrate obtained by vapor-depositing an inorganic compound such as silica, alumina or aluminum on polyethylene terephthalate or nylon film can be used, and the vapor-deposited surface may be coated with polyvinyl alcohol or the like.
The substrate 1 is preferably subjected to easy adhesion treatment on the surface to be printed (surface in contact with the printing layer). Examples of the easy adhesion treatment include corona discharge treatment, ultraviolet / ozone treatment, plasma treatment, and oxygen plasma treatment. , Primer treatment and the like. For example, in the corona discharge treatment, a hydroxyl group, a carboxyl group, a carbonyl group, etc. are expressed on the substrate. Since hydrogen bonds can be used, the ink preferably contains a compound having a functional group such as a hydroxyl group or an amino group.
The thickness of the substrate 1 is not particularly limited. In the case of a plastic film, the film normally used for printing can be applied as it is. For example, in the case of a PET film, 12 to 40 μm, and in the case of an oriented polypropylene (OPP) film, 20 to 50 μm can be suitably used.

<Manufacture of laminates>
The laminate of the present invention further comprises a substrate 2 in this order on the printed layer of the printed matter, and is produced by laminating (laminating) the printed matter and the substrate 2. In addition, the said laminated body has a preferable laminated body containing an adhesive layer, and the laminated body which has the base material 1, the printing layer, the adhesive bond layer, and the base material 2 in order is preferable. Examples of the adhesive layer include a layer made of an anchor coat agent, a urethane-based laminate adhesive, a molten resin, and the like. Examples of anchor coating agents (AC agents) include imine AC agents, isocyanate AC agents, polybutadiene AC agents, and titanium AC agents. Urethane laminate adhesives include polyether urethane laminate adhesives and polyester laminates. Examples thereof include an adhesive and the like, and those containing an organic solvent and those without a solvent. Moreover, molten polyethylene etc. are mentioned as molten resin.
As a method for producing a laminate, for example, a normal extrusion laminate (extrusion laminate) in which a molten polyethylene resin is laminated on a printed layer through various anchor coating agents such as imine, isocyanate, polybutadiene, and titanium. ) Method, a dry laminating method or non-solvent laminating method in which an adhesive such as urethane is applied to the printing surface and a plastic film is laminated thereon, or a direct laminating method in which molten polypropylene is directly pressed and laminated on the printing surface. It can be obtained by a known laminating process.

<Substrate 2>
As the base material 2, the thing similar to the base material 1 is mentioned suitably, and may be the same as that of the base material 1, or may differ. Unstretched polyethylene, unstretched polypropylene, nylon base material, aluminum foil base material, aluminum vapor deposition base material and the like are preferable.

<Ultraviolet laser marking>
Next, a laser marking method will be described. A laser that can be suitably used in this embodiment is an ultraviolet laser (for example, a third harmonic Nd; YAG laser, third harmonic YVO4 laser, etc. having a wavelength of 355 nm). Laser irradiation is generally performed from the substrate 1 side. However, when the base material 2 is transparent, laser irradiation may be possible not only from the base material 1 side but also from the base material 2.

  In addition to displaying the desired contents in alphanumeric characters, hiragana, kanji, etc., laser printing can also write a larger amount of various information as a barcode or a two-dimensional barcode. As the two-dimensional code, there are QR (model 1), QR (model 2), micro QR, DataMatrix, and the like. It is also possible to capture and draw photos and figures through a personal computer.

The laminate using the laser marking composition of the present invention prints directly inside the laminate, and the marking cannot be changed later. In addition, depending on the size of the laser printing place, characters, figures and codes, it is difficult for a third party to recognize the presence or contents of the third party, so that a function of preventing forgery can be exhibited.
In the laminate for laser marking of this embodiment, the laser marking printing layer is sandwiched between the base material 1 and the base material 2. For this reason, it is possible to prevent peeling, scattering, abrasion, and the like of the printed surface during printing and during use.

  The print quality by irradiation with an ultraviolet laser depends on the selection of 1) laser power, 2) scanning speed, and 3) Q switch frequency. The laser power is preferably printed with an output that does not cause damage (unevenness) at the irradiated portion of the laminate and the printing becomes clear. The scanning speed controls the interval between printing dots, printing time, etc., and it is performed at a scanning speed that can maintain the printing density and printing quality by appropriately scanning without concentrating the printing dots and without excessively spreading the printing dots. preferable. The Q switch frequency represents a frequency for generating a pulse. The Q switch frequency also affects print quality. It is preferable to adjust appropriately.

The laminate of the present invention can be usefully used as a label. For example, when the outermost layer of the laminate is further provided with an adhesive layer and release paper in this order, specifically, a bar code label, a product display label, etc., or a luggage tag, emblem having a similar function, Can be used for seals, stickers, etc.
The pressure-sensitive adhesive layer used for use as a label was coated with a coating liquid such as natural rubber, synthetic rubber, polyisobutylene, 2-ethylhexyl acrylate / n-butyl acrylate, an acrylic resin, a polyester resin, and the like, and dried. It is formed with a coating film. If necessary, a tackifier such as abietic acid rosin ester, a terpene / phenol copolymer, an isocyanate-based, and an epoxy-based curing agent can be used in the coating solution.

As the release paper, a release paper obtained by applying a silicone-based or fluorine-based release agent to a paper substrate, a laminated paper coated with a polyolefin resin, or the like can be used.
Laser irradiation can be performed before or after the label is applied to the object.

EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, this invention is not limited to these Examples. In the present invention, “parts” and “%” represent “parts by mass” and “% by mass” unless otherwise noted. Examples 3 to 6 , 12 to 16, and 18 are reference examples.
(Hydroxyl value)
It calculated | required according to JISK0070.
(Acid value)
It calculated | required according to JISK0070.
(Amine number)
The amine value was determined according to the following method in accordance with JISK0070 with the number of mg of potassium hydroxide equivalent to the equivalent amount of hydrochloric acid required to neutralize the amino group contained in 1 g of resin. 0.5-2 g of the sample was precisely weighed (sample solid content: Sg). To a precisely weighed sample, 50 mL of a mixed solution of methanol / methyl ethyl ketone = 60/40 (mass ratio) was added and dissolved. Bromophenol blue was added as an indicator to the obtained solution, and the obtained solution was titrated with a 0.2 mol / L ethanolic hydrochloric acid solution (titer: f). The point at which the color of the solution changed from green to yellow was taken as the end point, and the amine titer was determined by the following (formula 2) using the titration amount (AmL) at this time.
(Formula 2) Amine number = (A × f × 0.2 × 56.108) / S [mgKOH / g]

(Average particle size)
The average particle diameter of the metal oxide (A) is measured by diluting each laser marking composition with a mixed solvent of ethyl acetate / isopropanol = 50/50 (mass ratio) at 25 ° C. by a laser diffraction / scattering method. The value of D50 was defined as the average particle size. The measuring machine used was Microtrack WaveII-EX150 manufactured by Microtrack Bell.

(Weight average molecular weight)
The weight average molecular weight was determined as a converted molecular weight using polystyrene as a standard substance by measuring a molecular weight distribution using a GPC (gel permeation chromatography) apparatus (HLC-8220 manufactured by Tosoh Corporation). The measurement conditions are shown below.
Column: The following columns were used in series.
TSKgel SuperAW2500 manufactured by Tosoh Corporation
TSKgel SuperAW3000 manufactured by Tosoh Corporation
TSKgel SuperAW4000 made by Tosoh Corporation
TSKgel guardcolumnSuperAWH made by Tosoh Corporation
Detector: RI (differential refractometer)
Measurement conditions: Column temperature 40 ° C
Eluent: Tetrahydrofuran Flow rate: 1.0 mL / min

(Glass transition temperature (Tg))
The glass transition temperature (Tg) was determined by DSC (differential scanning calorimetry measurement). In addition, a measuring machine uses DSC8231 by Rigaku Corporation, measuring temperature range -70-250 degreeC, temperature increase rate 10 degree-C / min, the inflection point of the baseline change based on the glass transition in a DSC curve, glass transition temperature It was.

(Synthesis Example 1) [Synthesis of polyurethane resin PU1]
100 parts of a polyester polyol (hereinafter referred to as “MPD / AA”) having a number average molecular weight of 5000 which is a condensate of 3-methyl-1,5-pentanediol and adipic acid, and a number average molecular weight of 2000 being a condensate of propylene glycol and adipic acid. Polyester polyol (hereinafter "PP / AA") 24 parts, number average molecular weight 2000 polypropylene glycol (hereinafter "PPG") 16 parts, isophorone diisocyanate (hereinafter "IPDI") 20.5 parts, and ethyl acetate 73.7 parts Was reacted for 4 hours at 80 ° C. under a nitrogen stream to obtain a solvent solution of the terminal isocyanate urethane prepolymer. Next, 8.2 parts of isophorone diamine (hereinafter “IPDA”), 0.5 part of 2-ethanolamine (hereinafter “2 EtAm”), 222.9 parts of ethyl acetate, and 127.1 parts of isopropanol (hereinafter “IPA”) were mixed. The resulting terminal isocyanate prepolymer solution was gradually added at 40 ° C. and then allowed to react at 80 ° C. for 1 hour, solid content 30%, amine value 3.5 mgKOH / g, hydroxyl value 1.7 mgKOH / g A polyurethane resin PU1 solution having a weight average molecular weight of 50000 and a glass transition temperature of −40 ° C. was obtained.

(Synthesis Example 2) [Synthesis of Acrylic Resin Ac1]
A four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube was charged with 600 parts of IPA, and the temperature was raised to 80 ° C. in a nitrogen atmosphere with stirring. Next, 20 parts of acrylic acid prepared in advance, 58 parts of 2-hydroxyethyl methacrylate, 20 parts of methyl acrylate, 370 parts of methyl methacrylate, 130 parts of butyl acrylate and 12 parts of azobisisobutyronitrile were prepared. The mixture was added dropwise over 2 hours. One hour after the dropping, 2 parts of azobisisobutyronitrile was added, and the mixture was further reacted for 2 hours. After completion of the reaction, the solid content was adjusted with methyl ethyl ketone. Thus, an acrylic resin Ac1 solution having a solid content of 30%, an acid value of 26 mgKOH / g, a weight average molecular weight of 20000, a glass transition temperature of 46 ° C., and a content of methyl methacrylate structural units of 62% by mass was obtained.

Example 1
<Ultraviolet laser marking composition S1>
35 parts of zinc oxide A (zinc oxide particles average particle diameter 200 nm, primary particle diameter 25 nm, oil absorption 24 ml / 100 g), polyurethane resin PU1 solution 25 parts, vinyl chloride copolymer resin (Solvine TA5R: manufactured by Nissin Chemical Industry Co., Ltd., vinyl chloride: acetic acid 10 parts of vinyl: vinyl alcohol = 88: 1: 11 (mass ratio), solid content 25% ethyl acetate solution), 20 parts of ethyl acetate and 10 parts of isopropanol (IPA) are mixed, stirred with a disper, and then used with a sand mill. This was dispersed for 10 minutes to obtain an ultraviolet laser marking composition S1.

<Creation of printed matter and laminate>
(Printed matter)
The ultraviolet laser marking composition S1 was mixed with a Zahn cup No. 1 manufactured by Kogaisha using a mixed solvent of n-propyl acetate / isopropyl alcohol = 50/50. 3 for 16 seconds (25 ° C.), the viscosity is adjusted to dilute, and on the corona-treated surface side of each of the following substrates 1 (OPP, PET, NY) Laser 175 line Gravure printing was performed using a plate depth of 30 μm, and each printed matter was obtained.
-Corona-treated stretched polypropylene (OPP) film ("FOR" manufactured by Futamura Chemical Co., Ltd., thickness 20 μm)
-Corona-treated polyethylene terephthalate (PET) film (“E5100” manufactured by Toyobo Co., Ltd., thickness 12 μm)
-Corona-treated nylon (ONy) film ("ON-RT" manufactured by Unitika, thickness 15 μm)
(Laminate)
On the printed layer of the printed matter obtained above, an adhesive (“TM320 / CAT13B” manufactured by Toyo Morton) was applied to a dry coating amount of 3.5 g / m ^2, and an unstretched polypropylene film ( The above laminates were obtained by pasting together with “FHK2” manufactured by Futamura Chemical Co., Ltd., thickness 30 μm) by dry lamination.

(Examples 2 to 18) <Ultraviolet laser marking compositions S2 to S18>
A composition was prepared in the same manner as in Example 1 except that the raw materials and the composition shown in Table 1 were used. Further, printed materials (OPP, PET, ONy) and laminates (OPP, PET, ONy) were obtained in the same manner as described above. In addition, the abbreviation in a table | surface represents the following.
Cellulose resin: T.I. N. C. INDUSTRIAL CO. Nitrocellulose manufactured by LTD Product name TR2 Solid content 30% (methylcyclohexane / IPA / ethyl acetate solution)
・ Chlorinated polyolefin resin: (manufactured by Nippon Paper Industries Co., Ltd., chlorinated polypropylene resin, product name 370M, chlorine content 30%, solid content 50% solution)
Zinc oxide B: Zinc oxide particles (average particle size 50 nm, primary particle size 15 nm, oil absorption 28 ml / 100 g)
Zinc oxide C: Zinc oxide particles (average particle size 300 nm, primary particle size 35 nm, oil absorption 21 ml / 100 g)
Zinc oxide D: Zinc oxide particles (average particle size 400 nm, primary particle size 60 nm, oil absorption 16 ml / 100 g)
Titanium oxide: Titanium oxide particles (average particle size 100 nm, oil absorption 23 ml / 100 g)
・ Cerium oxide: Cerium oxide particles (average particle size 200 nm)
-Tin oxide: Tin oxide particles (average particle size 200 nm)
-Iron (III) oxide: Iron (III) oxide particles (average particle size 200 nm)

(Comparative Examples 1 to 6) <Ultraviolet laser marking compositions SS1 to SS6>
A composition was prepared in the same manner as in Example 1 except that the raw materials and the composition shown in Table 2 were used. Further, printed materials (OPP, PET, ONy) and laminates (OPP, PET, ONy) were obtained in the same manner as described above. In addition, the abbreviation in a table | surface represents the following.
-Polyacetal resin: Product name Iupital FU2025 manufactured by Mitsubishi Chemical Corporation
Silica: Silica particles (average particle size 300 nm)
-Barium sulfate: Barium sulfate (average particle size 300 nm)
Alumina: Aluminum oxide (average particle size 300 nm)
Magnesium oxide: Magnesium oxide (average particle size 300 nm)

<Performance evaluation>
Ultraviolet laser marking compositions obtained in Examples 1 to 18 and Comparative Examples 1 to 6 shown in Table 1 (S1 to S18 (Examples), SS1 to SS6 (Comparative Examples)), printed materials and laminates thereof The performance of was evaluated by the following method. The results are shown in Tables 3 and 4.

[Ink manufacturing aptitude]
The fluidity at the time of dispersing the sand mill when producing the ultraviolet laser marking composition (S1 to S18 (Example), SS1 to SS6 (Comparative Example)) was visually evaluated. The determination of fluidity is based on the fact that the viscosity of the composition during sand mill dispersion is Zahn Cup No. 4 is less than 30 seconds and is “good”. 4 is 30 to 90 seconds, “slightly low”. When it exceeded 90 seconds at 4, it was judged as “bad”.
A: Good fluidity during sand mill dispersion, easy ink preparation B: Slightly low fluidity during sand mill dispersion, but ink can be produced C: Poor fluidity during sand mill dispersion, ink cannot be produced Industrially usable evaluation Are A and B.

[Stability over time]
The ultraviolet laser marking composition (S1 to S18 (Example), SS1 to SS6 (Comparative Example)) was put in a glass bottle and sealed, and stored in an environment of 40 ° C. for 7 days, and then the state of the composition (viscosity change, precipitation) ) Change was evaluated. The change in viscosity is indicated by the Zahn Cup No. before and after storage. 4 was the difference in the number of seconds of outflow at 25 ° C.
A: No change in composition over time (viscosity change is less than 5 seconds and no precipitation)
B: Composition is slightly changed with time (viscosity change is 5 seconds or more and less than 20 seconds, and there is slight precipitation)
C: Remarkable change with time (viscosity change exceeds 20 seconds, precipitation is remarkable)
Industrially available ratings are A and B.

[Transparency of printed matter]
The transparency of the printed matter was evaluated for the printed matter (OPP) using the ultraviolet laser marking composition (S1 to S18 (Example), SS1 to SS6 (Comparative Example)). Transparency was evaluated by measuring total light transmittance (TT) using “SH7000” manufactured by Nippon Denshoku Industries Co., Ltd.
A: Good transparency (total light transmittance of 80% or more)
B: Inferior in transparency (total light transmittance of 50% or more and less than 80%)
C: Poor transparency (total light transmittance less than 50%)
Industrially available ratings are A and B.

[Base material adhesion]
The adhesiveness of the printed matter was evaluated for printed matter (OPP, PET, ONy) using the ultraviolet laser marking composition (S1 to S18 (Example), SS1 to SS6 (Comparative Example)). The evaluation was carried out by sticking to the printing layer using an adhesive tape (Cellotape (registered trademark) manufactured by Nichiban Co., Ltd.) and quickly peeling it off in the 90 ° direction of the printing layer to evaluate the degree of peeling of the printing layer.
A: Print layer peels off in area less than 20% of adhesive tape application part B: Print layer peels off in area of 20-50% of adhesive tape application part C: Print layer in area exceeding 50% of adhesive tape application part A and B are industrially applicable evaluations where peeling occurs.

[Laminate transparency]
Transparency was evaluated for laminates (OPP, PET, ONy) using ultraviolet laser marking compositions (S1 to S18 (Examples), SS1 to SS6 (Comparative Examples)). Transparency was evaluated by measuring total light transmittance (TT) using “SH7000” manufactured by Nippon Denshoku Industries Co., Ltd.
A: Good transparency (total light transmittance of 80% or more)
B: Inferior in transparency (total light transmittance 50 to 80%)
C: Poor transparency (total light transmittance less than 50%)
Industrially available ratings are A and B.

[Lamination strength]
The laminate strength of the laminate (OPP, PET, ONy) using the ultraviolet laser marking composition (S1 to S18 (Example), SS1 to SS6 (Comparative Example)) was evaluated according to the following criteria.
A: The laminate strength is 0.8 N / 15 mm or more.
B: Laminate strength is 0.3 N / 15 mm or more and less than 0.8 N / 15 mm.
C: Laminate strength is less than 0.3 N / 15 mm Industrially applicable evaluations are A and B.

(UV laser printing)
For a laminate (OPP, PET, ONy) using an ultraviolet laser marking composition (S1 to S18 (Example), SS1 to SS6 (Comparative Example)), an ultraviolet laser “MD-U1000C” (manufactured by Keyence Corporation) is used. Printing with an ultraviolet laser was performed under the following conditions. All printing was performed from the substrate 1 side.
1) Laser power 50%
2) Scanning speed 2000mm / sec 3) Q switch frequency 120kHz

[Visibility of laser printing]
Visibility (printing density) was visually evaluated for the laminate (OPP, PET, ONy) subjected to laser printing by the above method.
A: Print density is high and visibility is good B: Print density is not high, but visibility is C: Print density is low and visibility is industrially applicable is A and B.

[Irradiation spot irregularities (damage)]
About the laminated body which laser-printed by said method, the presence or absence of the unevenness | corrugation (damage) of an irradiation location was evaluated visually. In addition, unevenness | corrugation (damage | damage) means the state which the surface layer (base material 1) in a laminated body deform | transformed, surface roughness increased, and smoothness was lost.
A: There is no unevenness (damage) of the irradiated part.
C: Concavities and convexities (damage) are observed at the irradiated part.
The industrially available rating is A.

  From the above, when the ultraviolet laser marking composition of the present invention is used, the present application can provide a printed matter or a laminate excellent in visibility with an ultraviolet laser and excellent in transparency of a non-printing portion. In addition, it was shown that the printed layer of the printed material has good adhesion to the substrate, and that the composition can be easily produced, and that the composition has good stability over time.

Claims (6)

An ultraviolet laser marking composition comprising a binder resin and a metal oxide (A),
The binder resin contains a polyurethane resin and a vinyl chloride copolymer resin in a mass ratio of 95: 5 to 40:60 ,
The ultraviolet laser marking composition in which the metal oxide (A) contains zinc oxide and the average particle diameter of the metal oxide (A) is 5 to 400 nm. The ultraviolet laser marking composition of Claim 1 whose primary particle diameter of the said metal oxide (A) is 5-100 nm. Prints of a printing layer made of an ultraviolet laser marking composition according to claim 1 or 2 on the substrate 1. The printed matter according to claim 3 , wherein the total light transmittance of the printed layer is 50% or more. The laminated body which further has the base material 2 on the printing layer of the printed matter of Claim 3 or 4 . The manufacturing method of an ultraviolet laser printed matter which prints by irradiating an ultraviolet laser with respect to the printed matter or laminated body which comprises the printing layer which consists of an ultraviolet laser marking composition of Claim 1 or 2 .