JP7111124B2 - Gravure or flexographic inks and their use - Google Patents

Description

TECHNICAL FIELD The present invention relates to a gravure or flexographic ink suitable for use in packaging materials, particularly laminated laminates.

Gravure or flexographic inks are widely used as pattern printing for the purpose of imparting decorativeness and functionality to printed materials. Demands on printing inks are diversifying year by year, such as efforts to address environmental issues represented by laws and regulations.

Furthermore, as global warming countermeasures, at the 21st Conference of the Parties to the United Nations Framework Convention on Climate Change (COP21) held in 2015, each country submitted reduction targets. A draft commitment was submitted to reduce the effect gas by 26% (Patent Document 1). In order to realize this, for example, there is the concept of carbon neutrality. By doing this, if biomass materials such as plant materials are used and the amount of carbon dioxide emitted by combustion is the same as the amount of carbon dioxide absorbed and fixed by the growth of plants, etc., carbon dioxide in the air does not increase Therefore, plant-derived (biomass-derived) raw materials are used for gravure or flexo ink that can be used for film packaging materials. Efforts to improve it are urgently needed.

On the other hand, among gravure or flexographic inks, particularly those used for laminated laminates often use a polyurethane resin in order to maintain and improve the laminate strength. This is because by appropriately selecting the raw materials such as isocyanate and polyol, it is possible to freely design a coating film from a hard and tough coating film to a flexible and elastic coating film. However, even if a biomass-derived polyurethane resin is used, at least the same performance as the conventional one can of course be maintained, and further improvement in properties is required in the future. Therefore, among polyurethane resins, various studies have been conducted on a biomass-derived polyester polyol structure, which is a raw material for the structural units of polyurethane resins, in order to improve printability and laminate strength (Patent Documents 2 and 3).

For example, it is one of the important performances to control sanitary conditions such as taste and odor of the contents of a packaging bag using a laminate laminate. When conventional petroleum-derived inks of poor quality are used, by-products of ink raw materials, decomposition products, and trace impurities migrate into the contents, causing problems such as elution into the contents and deterioration of quality such as odor. There was a case.
For example, in Patent Document 4, the main component eluted into the contents is a cyclic dicarboxylic acid, but even with other compounds, even if the amount of elution is very small, there are some that greatly affect the odor, taste, etc. of the contents. .

JP 2018-062642 A WO2018/110664 pamphlet WO2018/199085 Pamphlet JP 2016-150944 A

The present invention provides good printability with gravure or flexo ink, good lamination strength in a laminate, and less influence of elution on the contents in a packaging bag using a laminate laminate, and An object of the present invention is to provide a gravure or flexographic ink using a biomass-derived polyurethane resin with little odor.

As a result of intensive studies in view of the above situation, the inventors have found that the problem can be solved by using the gravure or flexographic ink described below, and have completed the present invention.

That is, the present invention is a gravure or flexo ink having a binder resin containing a biomass polyurethane resin,
The polyurethane resin contains a structural unit derived from a polyester polyol obtained by condensation reaction of a dibasic acid and a diol, and the dibasic acid is at least one biomass dibasic acid selected from succinic acid, sebacic acid and dimer acid. and said diol relates to gravure or flexographic inks, including branched diols and linear diols.

The present invention also relates to the above gravure or flexo ink containing 65% by mass or more of biomass dibasic acid in 100% by mass of dibasic acid.

The present invention also relates to the above gravure or flexographic ink, wherein the dibasic acid is composed of at least one dibasic acid selected from succinic acid, sebacic acid and dimer acid.

The present invention also relates to the above gravure or flexographic ink, wherein the mass ratio of the branched diol and the linear diol (branched diol:linear diol) is 10:90 to 90:10.

The present invention also relates to the above gravure or flexo ink containing a vinyl chloride copolymer resin and/or a cellulose resin.

The present invention also relates to the above gravure or flexo ink, wherein the biomass polyurethane resin has a biomass degree of 40 to 100% by mass.

The present invention also relates to a printed matter having a printing layer made of the gravure or flexo ink on the substrate 1 .

The present invention also relates to a laminate having at least a base material 1, a printed layer made of the gravure or flexographic ink, and a base material 2 in this order.

With the gravure or flexo ink of the present invention, the printability is good, the lamination strength of the laminate is good, and the contents of the packaging bag using the laminate laminate are less affected by elution, and the odor of the printed matter is reduced. It was possible to provide gravure or flexo ink using a biomass-derived polyurethane resin with a small amount of

The gravure or flexographic ink of the present invention will be described below.

SUMMARY OF THE INVENTION The present invention is a gravure or flexographic ink having a binder resin comprising a biomass polyurethane resin.
Part or all of the polyurethane resin contains structural units derived from a polyester polyol composed of a dibasic acid and a diol. Part or all of the dibasic acid is at least one biomass dibasic acid selected from succinic acid, sebacic acid and dimer acid. Diols also include branched diols and linear diols.
Containing a biomass polyurethane resin as a binder resin contributes to environmental conservation, and the polyurethane resin contains at least one biomass dibasic acid selected from succinic acid, sebacic acid and dimer acid, a branched diol and a linear diol. By containing a polyester structure composed of a diol containing, there is an effect of imparting appropriate hardness and flexibility as a binder resin. As a result, it is thought that this contributes to the improvement of properties such as printability and laminate strength.

In this specification, "gravure or flexographic ink" may be simply referred to as "ink" or "printing ink", but they have the same meaning.
In addition, unless otherwise specified, % and part represent % by mass and part by mass, respectively.

(binder resin)
A binder resin is a binder resin component in gravure or flexo ink. The binder resin is preferably contained in an amount of 2 to 25% by mass, preferably 4 to 20% by mass, based on the total mass of the ink.

(biomass polyurethane resin)
In the present invention, the biomass polyurethane resin refers to a resin having a biomass degree of greater than 0, which will be described later. The biomass polyurethane resin is preferably contained in an amount of 30% by mass or more, more preferably 40% by mass or more, and still more preferably 60% by mass or more in the total mass of the polyurethane resin.
The biomass polyurethane resin in the present invention functions as a binder resin. The biomass polyurethane resin preferably has a weight average molecular weight of 10,000 to 100,000. More preferably 30,000 to 80,000. When the weight average molecular weight is within the range of 10,000 to 100,000, the laminate strength tends to improve.

The biomass degree of the biomass polyurethane resin in the present invention is preferably 40% by mass to 100% by mass, more preferably 45% by mass to 100% by mass, from the concept of carbon neutrality. In addition, the biomass content in the non-volatile matter of the gravure or flexo ink having a binder containing a biomass polyurethane resin in the present invention, that is, the biomass content of the printing layer is preferably 5% by mass or more, and is 7% by mass or more. is preferred, and 10% by mass is more preferred.

The biomass polyurethane resin in the present invention is a polyurethane resin obtained by condensation reaction of polyol and polyisocyanate, or a urethane prepolymer having an isocyanate group at the end, which is a condensation reaction product of polyol and polyisocyanate, and a polyamine. Polyurethane resins (polyurethane urea resins) obtained by reaction (referred to as chain extension) are preferred. It is particularly preferred that the polyol contains a high-molecular-weight polyol. Any one of the polyol, polyisocyanate and polyamine must contain a biomass-derived component.
Such a biomass polyurethane resin can be produced, for example, by the method described in WO2018/199085 pamphlet and Japanese Patent Application Laid-Open No. 2018-131624. It becomes a structural unit of polyurethane resin.

The polymer polyol preferably contains a polyester polyol obtained by reacting a biomass dibasic acid, which will be described later, as a raw material component, and has a weight average molecular weight of 400 to 10,000. In addition, it is preferable to contain 50 mass % or more of polyester polyol in raw material polyol, and it is still more preferable to contain 70 mass % or more.
Further, polymer polyols other than the above polyester polyols may be used in combination. Such polymeric polyols include polyether polyols, polycarbonate polyols and polyolefin polyols. These are preferably used in an amount of 50% by mass or less in the total amount of raw material polyols. Polyether polyols are preferred from the standpoint of plate fogging as polymer polyols used in combination with polyester polyols. Among polyether polyols, polytrimethylene glycol, polytetramethylene glycol, polypropylene glycol, polyethylene glycol and their copolymerization preferably an object.

(polyester polyol)
The polyester polyol contains structural units derived from a polyester polyol obtained by condensation reaction of a dibasic acid and a diol, and part or all of the dibasic acid is a biomass dibasic acid. Here, the biomass dibasic acid is a biomass-derived dibasic acid, and in the present invention, at least one biomass dibasic acid selected from succinic acid, sebacic acid and dimer acid is essential. The biomass dibasic acid must be contained at 65% by mass or more in the total weight of the dibasic acid of the raw material of the polyester polyol, preferably at 70% by mass or more, and at least 85% by mass. More preferably, it is more preferably composed only of biomass dibasic acid. Moreover, it is preferable that at least 65% by mass or more of at least one kind of biomass dibasic acid selected from succinic acid, sebacic acid and dimer acid is contained in the total amount of biomass dibasic acid. Further, it is more preferably a dibasic acid consisting of at least one selected from succinic acid, sebacic acid and dimer acid, and a dibasic acid consisting of any one of them is also preferred. At least one kind of biomass dibasic acid selected from succinic acid, sebacic acid and dimer acid is obtained as a commercial product such as Ito Seiyu Co., Ltd., for example.

The dibasic acid may contain a dibasic acid other than biomass dibasic acid, and such dibasic acids include adipic acid, phthalic acid, isophthalic acid, terephthalic acid, maleic acid, fumaric acid, oxalic acid, Malonic acid, glutaric acid, pimelic acid, spelic acid, azelaic acid, trimellitic acid, pyromellitic acid, and the like. Also, succinic acid, sebacic acid and dimer acid not derived from biomass are not excluded.

The diols include both branched diols and linear diols. As a result, the lamination strength of the laminate is improved. Here, the linear diol is a diol having 2 or more atoms, and includes alkylene glycol, dialkylene glycol, trialkylene glycol and other diols. A branched diol is a diol in which at least one hydrogen atom of the hydrocarbon group of alkylene glycol is replaced with a non-hydrogen atom.

The straight-chain diol imparts crystallinity and the branched diol imparts flexibility, and the balance between them provides a tough ink film for the polyurethane resin as the binder resin, resulting in high laminate strength.

Examples of the branched diols include 2-butyl-2-ethyl-1,3-propanediol (hereinafter also referred to as BEPG), 2-methyl-1,3-propanediol (hereinafter also referred to as MPO), 3-methyl-1,5-pentanediol (also referred to as MPD), neopentyl glycol (also referred to as NPG), 1,2-propylene glycol (hereinafter also referred to as PG), 2,4-diethyl-1,5-pentane diol, 1,3-butanediol, dipropylene glycol and the like.
In the present invention, at least one branched diol selected from MPO, MPD, BEPG, NPG, PG, and 2,4-diethyl-1,5-pentanediol is preferred, and NPG and/or BEPG are more preferred. It is particularly preferred to use BEPG.

The linear diol is preferably alkylene glycol, and such compounds include ethylene glycol (also referred to as EG), diethylene glycol, 1,3-propanediol (also referred to as 1,3PD), 1,4- butanediol (also referred to as 1,4-BD), 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 1,4-butynediol, 1,4 - butylene diol, diethylene glycol, triethylene glycol and the like.
Among them, linear diols having 8 or less carbon atoms, preferably 6 or less carbon atoms are preferable, and EG, 1,3PD, 1,4-BD, 1,5-pentanediol, 1,6-hexanediol, 1,8- Octanediol, etc. are preferred. Furthermore, EG, 1,3PD, and 1,4-BD are particularly preferable from the viewpoint of biomass degree and physical properties.

In the present invention, from the viewpoint of laminate strength, the mass ratio of branched diols and linear diols (branched diols: linear diols) in the total diols of the polyester polyol is from 10:90 to 90:10. Preferably, it is more preferably 20:80 to 80:20. It is more preferably 30:70 to 70:30.

The branched diol units and the linear diol units may each exist in one polyester polyol, or a polyester polyol containing only branched diol units and a polyester polyol containing only linear diol units may be used. It may be used as a mixed raw material and used as a biomass urethane resin. Approximately the same effect is obtained.

Diisocyanates are preferred as polyisocyanates in the present invention, and various known aromatic, aliphatic or alicyclic diisocyanates can be used as such compounds. For example, 1,5-naphthylene diisocyanate, 4,4′-diphenylmethane diisocyanate, 4,4′-diphenyldimethylmethane diisocyanate, 4,4′-dibenzyl isocyanate, dialkyldiphenylmethane diisocyanate, tetraalkyldiphenylmethane diisocyanate, 1,3- Phenylene diisocyanate, 1,4-phenylene diisocyanate, tolylene diisocyanate, butane-1,4-diisocyanate, hexamethylene diisocyanate, isopropylene diisocyanate, methylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4- trimethylhexamethylene diisocyanate, cyclohexane-1,4-diisocyanate, xylylene diisocyanate, isophorone diisocyanate, lysine diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, methylcyclohexane diisocyanate, m- Representative examples include tetramethylxylylene diisocyanate and dimer diisocyanate obtained by converting the carboxyl group of dimer acid to an isocyanate group. These can be used alone or in combination of two or more. Among them, isophorone diisocyanate, tolylene diisocyanate, and 4,4'-diphenylmethane diisocyanate are preferred, and isophorone diisocyanate is more preferred from the viewpoint of solubility.

The above polyamine is preferably an organic diamine, and examples of such diamines include ethylenediamine, propylenediamine, hexamethylenediamine, isophoronediamine, dicyclohexylmethane-4,4'-diamine, and the like. In addition, 2-hydroxyethylethylenediamine, 2-hydroxyethylpropyldiamine, 2-hydroxyethylpropylenediamine, di-2-hydroxyethylethylenediamine, di-2-hydroxyethylenediamine, di-2-hydroxyethylpropylenediamine, 2-hydroxypyro Amines having a hydroxyl group in the molecule, such as pyrethylenediamine and di-2-hydroxypyropyrethylenediamine, can also be used. Although these organic diamines can be used singly or in combination of two or more, isophoronediamine is preferred. In addition, diethylenetriamine, iminobispropylamine: (IBPA, 3,3′-diaminodipropylamine), N-(3-aminopropyl)butane-1,4-diamine: (spermidine), 6,6-iminodihexylamine , 3,7-diazanonane-1,9-diamine, N,N'-bis(3-aminopropyl)ethylenediamine, and other polyfunctional amines having 3 or more amino groups can be used in combination with the above organic diamines.

In the present invention, the polyurethane resin preferably has an amine value. The amine value of the polyurethane urea resin is preferably 1 to 13 mgKOH/g. Within this range, the laminate strength to the substrate tends to improve.

A monoamine may be used as a reaction terminator for chain extension reactions using polyamines. Examples of the reaction terminator include dialkylamines such as dibutylamine, diethylamine and dipropylamine, as well as monoethanolamine, diethanolamine, 2-amino-2-methyl-1-propanol, tri(hydroxymethyl)aminomethane, Amines having a hydroxyl group such as can also be used.

In the gravure or flexographic ink using the biomass polyurethane resin of the present invention, various resins can be used in combination with the biomass polyurethane resin depending on the application and substrate. Examples of resins used include biomass polyurethane resins and polyurethane urea resins other than those described above, vinyl chloride copolymer resins, chlorinated polypropylene resins, ethylene-vinyl acetate copolymer resins, vinyl acetate resins, polyamide resins, and cellulose resins. Nitrocellulose resin, acrylic resin, polyester resin, alkyd resin, polyvinyl chloride resin, rosin resin, rosin-modified maleic acid resin, terpene resin, phenol-modified terpene resin, ketone resin, cyclized rubber, chlorinated rubber, polybutyral, petroleum Resins, modified resins thereof, and the like can be mentioned. These resins can be used alone or in combination of two or more. Among them, vinyl chloride copolymer resins and/or cellulose resins are preferred. Also, the content thereof is preferably 1 to 6% by mass based on the total mass of the ink. The mass ratio of the polyurethane resin containing the biomass polyurethane resin to the vinyl chloride copolymer resin and/or the cellulose resin is preferably 95:5 to 30:70, and preferably 95:5 to 50:50. is still more preferable, and it is even more preferable to contain 90:10 to 65:35.
The total amount of the polyurethane resin containing the biomass polyurethane resin, the vinyl chloride copolymer resin and/or the cellulose resin is preferably 60% by mass or more, more preferably 70% by mass or more, in the total mass of the binder resin. , more preferably 80% by mass or more.

<Vinyl chloride copolymer resin>
The vinyl chloride copolymer resin is not particularly limited as long as it contains structural units derived from vinyl chloride and structural units derived from other monomers. Among them, 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 preferably has a weight average molecular weight of 5,000 to 100,000, more preferably 20,000 to 70,000. is more preferred. The structure derived from the vinyl acetate monomer in 100% by mass of the solid content of the vinyl chloride-vinyl acetate copolymer resin is preferably 1 to 30% by mass, and the structure derived from the vinyl chloride monomer is preferably 70 to 95% by mass. . In this case, the solubility in organic solvents is improved, and the adhesion to substrates, film physical properties, laminate strength and the like are improved.
Further, since the solubility in organic solvents is improved, those containing hydroxyl groups derived from vinyl alcohol by saponification reaction or copolymerization are more preferable, and the hydroxyl value is preferably 20 to 200 mgKOH/g. Also, the glass transition temperature is preferably 50°C to 90°C.

<Vinyl chloride-acrylic copolymer resin>
Vinyl chloride-acrylic copolymer resin is mainly composed of copolymer resin of vinyl chloride monomer and acrylic monomer. ) preferably contains hydroxyalkyl acrylates. The acrylic monomer may be incorporated into the main chain of polyvinyl chloride in blocks or randomly, or may be graft-polymerized to the side chains 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. Also, the hydroxyl value is preferably 20 to 200 mgKOH/g, and the glass transition temperature is preferably 50°C to 90°C.

Further, the structure derived from the vinyl chloride monomer in the vinyl chloride-acrylic copolymer resin is preferably 70 to 95% by mass based on 100% by mass of the solid content of the vinyl chloride-acrylic copolymer resin. In this case, the solubility in an organic solvent is improved, and the adhesion to the substrate, film physical properties, laminate strength, etc. are improved.

In the following description, (meth)acrylic or (meth)acrylate means methacrylic and acrylic, methacrylate and acrylate respectively.

The acrylic monomer preferably contains a hydroxyl group, examples of which include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, (meth) (meth)acrylates such as 2-hydroxybutyl acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, and 8-hydroxyoctyl (meth)acrylate ) Acrylic acid hydroxyalkyl esters, glycol mono(meth)acrylates such as polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, 1,4-cyclohexanedimethanol mono(meth)acrylate, caprolactone-modified (meth) acrylates, hydroxyethylacrylamide, and the like. Among these, 2-hydroxyethyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and 2-hydroxypropyl acrylate are more preferable because they improve solubility in solvents. These can be used alone or in combination of two or more. In addition, acrylic monomers other than those described above may be contained at any time.

<Cellulose resin>
Cellulosic resins include, for example, nitrocellulose, cellulose acetate propionate, cellulose acetate butyrate, hydroxyalkyl cellulose, carboxyalkyl cellulose, etc. Examples of the alkyl group include methyl group, ethyl group, propyl group, isopropyl group, A butyl group, an isobutyl group, a pentyl group, a hexyl group and the like can be mentioned, and the alkyl group may further have a substituent. Among them, at least one selected from cellulose acetate propionate, cellulose acetate butyrate, and nitrocellulose is preferable. The weight average molecular weight is preferably 5,000 to 200,000, more preferably 10,000 to 80,000. Further, those having a glass transition temperature of 100° C. to 160° C. are preferable. The nitrogen content of the nitrocellulose is preferably 10-13% by mass, more preferably 10.5-12.5% by mass.

(pigment)
The gravure or flexo ink in the present invention preferably contains a pigment as a coloring agent, preferably an inorganic pigment or an organic pigment. C.I. described in the Color Index I. Pigments can be used as appropriate.
Examples of inorganic pigments include titanium oxide, zinc oxide, zinc sulfide, barium sulfate, calcium carbonate, aluminum hydroxide, chromium oxide, silica, carbon black, aluminum, and mica (mica). From the viewpoints of coloring power, hiding power, chemical resistance, and weather resistance, titanium oxide is preferred as the white pigment, and titanium oxide having a basic pigment surface is more preferred. Although aluminum is in the form of powder or paste, it is preferable to use it in the form of paste from the standpoint of handling and safety, and it may be either leafing or non-leafing. Barium sulfate, calcium carbonate and aluminum hydroxide are called extenders and are used as extenders to improve fluidity, strength and optical properties.
Examples of the above organic pigments include, but are not limited to, soluble azo, insoluble azo, azo, phthalocyanine, halogenated phthalocyanine, anthraquinone, anthrone, dianthraquinone, anthrapyrimidine, perylene, perinone, quinacridone, thioindigo, dioxazine, isoindolinone, quinophthalone, azomethineazo, flavanthrone, diketopyrrolopyrrole, isoindoline, indanthrone, carbon black, etc. pigments. Also, for example, Carmine 6B, Lake Red C, Permanent Red 2B, Disazo Yellow, Pyrazolone Orange, Carmine FB, Chromophtal Yellow, Chromophtal Red, Phthalocyanine Blue, Phthalocyanine Green, Dioxazine Violet, Quinacridone Magenta, Quinacridone Red, Indance Ron blue, pyrimidine yellow, thioindigo Bordeaux, thioindigo magenta, perylene red, perinone orange, isoindolinone yellow, aniline black, diketopyrrolopyrrole red, daylight fluorescent pigments, etc., listed in the color index. They can be used together at any time.

The pigment is preferably contained in an amount sufficient to ensure the density and tinting strength of the ink, that is, in a proportion of 1 to 50% by mass relative to the total mass of the printing ink. It is still more preferable that it is contained at 3 to 25% by mass,

(Other additives)
The ink of the present invention may contain a leveling agent, an antifoaming agent, a wax, a silane coupling agent, a plasticizer, a light stabilizer, silica particles, an infrared absorbent, an ultraviolet absorbent, a fragrance, a flame retardant, and a curing agent, if necessary. Additives such as agents can also be included.

(Organic solvent)
The ink of the present invention preferably contains an organic solvent as a liquid medium. The organic solvent to be used is preferably used as a mixed solvent, and includes 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, and isobutyl acetate. , ester-based organic solvents, and alcohol-based organic solvents such as methanol, ethanol, n-propanol, isopropanol, n-butanol, and the like can be used. Among them, organic solvents such as toluene and xylene that do not contain aromatic organic solvents (non-toluene organic solvents) are more preferable. More preferably, it is an organic solvent that does not contain an aromatic organic solvent and/or a ketone organic solvent such as methyl ethyl ketone (hereinafter referred to as "MEK"). ) is preferably contained as In particular, one containing an ester-based organic solvent and an alcohol-based organic solvent is preferable.

(Ink manufacturing method)
The gravure or flexographic ink of the present invention can be produced by dispersing a pigment with a binder resin or the like in an organic solvent using a dispersing machine, and mixing the resulting pigment dispersion with a binder resin, various additives, an organic solvent, or the like. . Commonly used dispersing machines, such as roller mills, ball mills, pebble mills, attritors and sand mills, can be used. The particle size distribution of the pigment in the pigment dispersion is adjusted by appropriately adjusting the size of the grinding media of the disperser, the filling rate of the grinding media, the dispersion processing time, the ejection speed of the pigment dispersion, the viscosity of the pigment dispersion, and the like. be able to. The present invention can also be applied to mediums containing no pigment.

The viscosity of the gravure or flexographic ink is in the range of 10 mPa·s or more at 25° C. from the viewpoint of preventing sedimentation of the pigment and appropriately dispersing it, and 1000 mPa·s or less from the viewpoint of work efficiency during ink production and printing. is preferred. It is more preferably 20 to 500 mPa·s. As the viscosity, a viscosity value measured at 25° C. with a B-type viscometer manufactured by Tokimec can be used.

(curing agent)
The gravure or flexo ink is also preferably used as a two-liquid type gravure or flexo ink by adding an isocyanate curing agent to improve lamination strength. Such isocyanate-based curing agents include, for example, tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), and hexamethylene diisocyanate (HDI), such as adduct-type polyisocyanate (adduct), biuret-type polyisocyanate (biuret), and isocyanate. A nurate-type polyisocyanate (isocyanurate) and the like can be suitably used, and examples thereof include an adduct obtained from the reaction of 1 mol of trimethylolpropane and 3 mol of HDI, a biuret obtained from the reaction of 1 mol of water and 3 mol of HDI, An isocyanurate obtained from a cyclotrimerization reaction of HDI and the like can be mentioned. When used as a two-liquid type, the amount of the polyisocyanate curing agent added is preferably 0.5 to 10% by mass, preferably 0.5 to 5% by mass, based on the total amount of the ink of the present invention.

(gravure or flexographic ink printing)
The ink in the present invention can also be used for gravure printing and flexographic printing. In gravure printing, they are diluted with a diluting solvent to a viscosity and concentration suitable for printing, and supplied to each printing unit singly or in combination.

<Gravure printing>
(gravure version)
When the gravure or flexo ink in the present invention is gravure printed, it is printed using a gravure plate. In the present invention, the gravure plate is made of metal and has a cylindrical shape. There are no restrictions on the use of engraving and laser, and settings can be made arbitrarily according to the pattern. A line number of 100 to 300 lines/inch is appropriately used, and the higher the number of lines, the higher the precision of printing.
(Printer)
A printing machine equipped with the above-mentioned gravure plate can be suitably used as the printing machine. Normally, a printing unit is installed for each color, and each unit is equipped with a doctor blade that scrapes off the ink while the gravure plate rotates. be taken. A furnisher roll can optionally be used for gravure printing. Each unit also has a drying oven through which the printed substrate is dried. The drying temperature is usually about 40-60°C.

<Flexographic printing>
(flexographic plate)
Examples of the plate used for flexographic printing in the present invention include a photosensitive resin plate utilizing ultraviolet curing with a UV light source and an elastomer material plate using a direct laser engraving system. Regardless of the method of forming the image area of the flexographic plate, a plate having a screening ruling of 75 lpi or more is used. Any sleeve or cushion tape for attaching the plate can be used.
(Printer)
Flexographic printing machines include CI type multicolor flexographic printing machines, unit type multicolor flexographic printing machines, etc. As for the ink supply system, a chamber system and a two-roll system can be mentioned, and an appropriate printing machine can be used. can.

<Base material 1>
The gravure or flexographic ink of the present invention is printed on the base material 1 or on the surface or back surface of the base material 1 of the laminate including the base material 1 and the base material 2 to form a printed matter.
Substrates to which the gravure or flexo ink of the present invention can be applied include polyethylene, polypropylene and other polyolefin substrates, polycarbonate substrates, polyester substrates (polyethylene terephthalate, polylactic acid, etc.), polystyrene substrates, AS resins, ABS resins, and the like. Polystyrene base material, polyamide base material, polyvinyl chloride base material, polyvinylidene chloride base material, cellophane base material, paper base material, aluminum foil base material, etc., or a film or sheet made of these composite materials There is something like Among them, a polyester base material and a polyamide base material having a high glass transition temperature are preferably used.

The base material may be subjected to vapor deposition coating treatment such as metal oxide on the surface and/or coating treatment such as polyvinyl alcohol. For example, GL- Examples include AE and IB-PET-PXB manufactured by Dai Nippon Printing Co., Ltd. Further, if necessary, those treated with additives such as antistatic agents and ultraviolet inhibitors, and those treated with corona treatment or low-temperature plasma treatment on the surface of the base material can also be used.

<Base material 2>
Substrate 2 may be the same as substrate 1 and may be the same or different. A thermoplastic substrate (sometimes referred to as a sealant) is preferable, and an unstretched polyethylene substrate, an unstretched polypropylene substrate, an unstretched polyester substrate, or the like is preferable.

<Laminate>
It is also possible to produce a laminate using the printed material. Such a laminate is a laminate having at least the base material 1, the printed layer, and the base material 2 in this order. It is preferable to use a laminate having at least a base material 1, a printed layer, an adhesive layer, and a base material 2 in this order.
The laminate of the present invention is obtained by providing an adhesive layer on a printed layer of a printed matter printed with gravure or flexographic ink, and bonding (laminating) the base material 2 together. A typical example of lamination processing is a dry lamination method or the like. The dry lamination method is a method in which an adhesive is applied onto a printed layer of a printed material, dried, and laminated by thermocompression bonding with a sealant.

<Adhesive layer>
The adhesive layer is obtained by applying an adhesive and drying it. As the adhesive, a two-liquid type adhesive comprising a mixture of a polyol and an isocyanate curing agent is suitable, and examples of the polyol include polyester-based and polyether-based adhesives. Specific examples include TM-250HV/CAT-RT86L-60, TM-550/CAT-RT37, TM-314/CAT-14B manufactured by Toyo-Morton Co., Ltd.

EXAMPLES The present invention will be described in detail below with reference to examples, but the following embodiments are merely examples of the present invention, and the present invention is not limited to these examples. Parts and % in the present invention represent parts by mass and % by mass unless otherwise specified.

<Method for measuring amine value>
The amine value was obtained in mg of potassium hydroxide equivalent to the equivalent of hydrochloric acid required to neutralize the amino groups contained in 1 g of the resin according to JIS K0070 according to the following method.
0.5 to 2 g of the sample was accurately weighed (sample solid content: Sg). 50 mL of a mixed solution of methanol/methyl ethyl ketone=60/40 (mass ratio) was added to the accurately weighed sample to dissolve the sample. Bromophenol blue was added to the resulting solution as an indicator, and the resulting solution was titrated with a 0.2 mol/L ethanolic hydrochloric acid solution (potency: f). The point at which the color of the solution changed from green to yellow was defined as the end point, and the titration amount (AmL) at this time was used to determine the amine value by the following (formula 1).
(Formula 1) Amine value = (A x f x 0.2 x 56.108) / S [mgKOH/g]

<Method for measuring number average molecular weight (Mn) and mass average molecular weight (Mw)>
The number average molecular weight (Mn) and mass average molecular weight (Mw) were measured using GPC (gel permeation chromatography) "Shodex GPCS System-21" manufactured by Showa Denko. GPC is liquid chromatography for separating and quantifying a substance dissolved in a solvent based on the difference in molecular size. The solvent was tetrahydrofuran, and the molecular weight was determined in terms of polystyrene.

<Method for measuring hydroxyl value>
It was determined according to the method described in JISK0070.

<Method for measuring acid value>
It was determined according to the method described in JISK0070.

[Synthesis Example 1-1] (Synthesis of polyester polyol A1)
2.6 parts of 1,3-propanediol (hereinafter also abbreviated as 1,3-PD), 2-butyl 2-ethyl 1, 49.4 parts of 3-propanediol (hereinafter also abbreviated as BEPG), 48 parts of succinic acid, and 0.002 parts of tetrabutyl titanate were charged, and esterification was carried out for 8 hours at 230°C under a stream of nitrogen while removing water generated by condensation. gone. After confirming that the acid value of the polyester became 15 or less, the degree of vacuum was gradually raised by a vacuum pump to complete the reaction. As a result, a polyester polyol (A1) having a number average molecular weight of 2000, a hydroxyl value of 56.1 mgKOH/g, an acid value of 0.3 mgKOH/g and a biomass content of 50.6% was obtained.

[Synthesis Examples 1-2 to 1-16] (Synthesis of polyester polyols A2 to A16)
Polyester polyols A2 to A16 were obtained in the same manner as in Synthesis Example 1-1, except that the raw materials and charging ratios shown in Table 1 were used. In addition, the abbreviations described in the table represent the following.
BEPG: 2-butyl-2-ethyl-1,3-propanediol (derived from petroleum)
MPO: 2-methyl-1,3-propanediol (petroleum-derived)
MPD: 3-methyl-1,5-pentanediol (derived from petroleum)
NPG: Neopentyl glycol (plant-derived biomass degree 40%)
PG: 1,2-propylene glycol (plant-derived biomass degree 100%) EG: ethylene glycol (plant-derived biomass degree 100%)
1,3-PD: 1,3-propanediol (plant-derived biomass degree 100%)
In the above, the degree of biomass of NPG is derived from Perstorp's catalog value.
・Dibasic acid in the table is the following biomass degree.
Succinic acid: (derived from biomass, biomass degree 100%)
Adipic acid: (derived from petroleum)
Sebacic acid: (derived from biomass, biomass degree 100%)
Dimer acid: (derived from biomass, biomass degree 100%)

The degree of biomass refers to the ratio of plant-derived or other biomass-derived substances contained in the compound.
Degree of biomass = 100 x mass of biomass-derived components of relevant compound/total mass of relevant compound.
However, if the compound is a reaction product of a biomass-derived raw material and a non-biomass-derived raw material, it is converted into the raw material before the reaction and calculated. For example, in the case of a polyester resin (polyester polyol) that is a reaction product of a dibasic acid and a diol,
Biomass degree = 100 x (biomass dibasic acid + biomass-derived diol) / (all dibasic acids + all diols)
"All diacids + all diols" refers to the sum of biomass-derived and non-biomass-derived diacids and biomass-derived and non-biomass-derived diols.

[Comparative Synthesis Examples 1-1 to 1-3] (Synthesis of polyester polyols B1 to B3)
Polyester polyols B1 to B3 were obtained in the same manner as in Synthesis Example 1-1, except that the raw materials and charging ratios shown in Table 1 were used.

[Synthesis Example 2-1] (Synthesis of polyurethane resin P1)
23.6 parts of polyester polyol A1, 4.68 parts of isophorone diisocyanate (hereinafter also abbreviated as IPDI), and 7.6 parts of ethyl acetate were placed in a four-necked flask equipped with a stirrer, thermometer, reflux condenser and nitrogen gas inlet tube. 5 parts of tin 2-ethylhexanoate and 0.003 part of tin 2-ethylhexanoate were charged, reacted at 120° C. for 6 hours under a nitrogen stream, added with 7.5 parts of propyl acetate and cooled to obtain a solution of a terminal isocyanate prepolymer. Then, to a mixture of 1.72 parts of isophoronediamine (hereinafter also abbreviated as IPDA), 34 parts of ethyl acetate and 21 parts of isopropyl alcohol (hereinafter also abbreviated as IPA), the obtained solution of the terminal isocyanate prepolymer was gradually added at room temperature. Then, the mixture was reacted at 50° C. for 1 hour to obtain a polyurethane resin P1 solution having a solid content of 30%, a mass average molecular weight of 70,000, an amine value of 4 mgKOH/g, and a biomass content of 40% by mass.

[Synthesis Examples 2-2 to 2-24] (Synthesis of polyurethane resins P2 to P24)
Polyurethane resins P2 to P24 were obtained in the same manner as in Synthesis Example 2-1, except that the raw materials and charging ratios shown in Tables 2-1 and 2-2 were used. Incidentally, in Synthesis Examples 2-17 and 2-18, 11.8 parts of polyester polyol B1 were used together. The biomass degree, etc. are shown in the same table.

[Comparative Synthesis Examples 2-1 to 2-3]
Polyurethane resins PP1 to PP3 were obtained in the same manner as in Synthesis Example 2-1, except that the raw materials and charging ratios shown in Table 2-3 were used. The biomass degree, etc. are shown in the same table.

[Example 1] (Production of ink S1)
10 parts of copper phthalocyanine indigo (LIONOL BLUE FG-7330 manufactured by Toyocolor Co., Ltd.), 10 parts of polyurethane resin P1 solution, vinyl chloride-vinyl acetate resin solution (hydroxyl value is 140 mg KOH / g, weight average molecular weight is 50000 vinyl chloride-acetic acid 5.0 parts of a vinyl copolymer resin (30% solid content solution) and 10 parts of a mixed solvent (propyl acetate/IPA = 75/25 (mass ratio)) are stirred and mixed, kneaded in a sand mill, and then 30 parts of a polyurethane resin (B1). 35 parts of a mixed solvent (normal propyl acetate/isopropyl alcohol = 75/25 (mass ratio)) were stirred and mixed to obtain a blue printing ink S1.

[Examples 2 to 34] (Production of inks S2 to S34)
Inks S2 to S34 were obtained in the same manner as in Example 1, except that the raw materials and charging ratios shown in Tables 3-1 and 3-2 were used. Note that descriptions in the table represent the following.
Titanium oxide: Titanium oxide Titanix JR-805 manufactured by Tayka
Nitrocellulose: nitrocellulose solid content 30% solution with a weight average molecular weight of 40,000 and a nitrogen content of 12% by weight

[Comparative Examples 1 to 3] (Production of inks SS1 to SS3)
Inks SS1 to SS3 were obtained in the same manner as in Example 1, except that the raw materials and charging ratios shown in Table 3-3 were used.

[Preparation of printed matter using ink S1]
The viscosity of ink S1 was diluted with a propyl acetate/IPA mixed solvent (mass ratio of 70/30) to adjust the viscosity in Zahn cup #3 (manufactured by Rigosha) to 15 seconds (at 25 ° C.), and a plate depth of 30 μm gravure plate was prepared. Using the equipped gravure proofing machine, print on the corona-treated surface of a single-sided corona-treated polypropylene (OPP) film (Pylen P2161 manufactured by Toyobo Co., Ltd.) and a single-sided corona-treated polyethylene terephthalate (PET) film (E5100 #12 manufactured by Toyobo Co., Ltd.). After drying at 40 to 50° C., printed matter (OPP, PET) using ink S1 was obtained.

[Preparation of printed matter using inks S2 to S34 and inks SS1 to SS3]
Prints (OPP, PET) were obtained using inks S2 to S34 and inks SS1 to SS3 in the same manner as in the examples of prints using ink S1, except that inks S2 to S34 and inks SS1 to SS3 were used. .

[evaluation]
Using the inks S1 to S34 (Examples), SS1 to SS3 (Comparative Examples) and their printed materials (OPP, PET) obtained in the above Examples and Comparative Examples, the taste of the contents was evaluated by the method described below. A test and lamination strength evaluation were performed.

[Elution component test (PET/CPP configuration)]
The inks S1 to S34 (Examples) and SS1 to SS3 (Comparative Examples) obtained in the above Examples and Comparative Examples were applied onto the printed layer of the PET film printed matter using a dry laminator at a line speed of 40 m/min. An adhesive was applied, and at the same time, a non-stretched polypropylene (CPP) film (ZK93KM manufactured by Toray Industries, Inc., thickness 60 μm) was laminated to obtain a laminate having a printed layer.
TM-550/CAT-RT37 manufactured by Toyo-Morton Co., Ltd. was used as an adhesive for dry lamination. After that, the laminate was cut into a size of 12 cm in width and 22 cm in length, and the edges were heat-sealed (temperature: 190 ° C., pressure: 2 kgf, time: 1 second) with the CPP faces inside to make a packaging bag, and water was used as the content. and boiled at 85°C for 20 minutes.
The boiled water was analyzed by gas chromatography/mass spectrometry (GC/MS) to confirm the presence or absence of peaks of organic components. The GC/MS apparatus and columns are as follows.
Apparatus: HP-GC6890N / MSD5973 (manufactured by Agilent Technologies) / TDS (manufactured by GERSTEL) Column: HP-5 (inner diameter 0.32 mm / length 60 m / film thickness 1.00 μm) (Agilent Technologies) made)
(Evaluation criteria)
5: Organic substances other than cyclic diesters were not detected, and the boiled water was odorless. (excellent)
4: Organic substances other than cyclic diesters were detected, and the boiled water was odorless. (good)
3: Organic substances other than cyclic diesters were detected, and the boiled water had a slight odor. (possible)
2: Organic substances other than cyclic diesters were detected, and the boiled water had an odor. (impossible)
1: A peak attributed to the cyclic diester was confirmed, and the boiled water had an odor. (inferior)
The practical level is 3-5.

[Elution component test (PET/LLDPE configuration)]
In the above elution test, linear low density polyethylene (LLDPE) (L4104 film thickness 50 μm manufactured by Toyobo Co., Ltd.) was used instead of unstretched polypropylene (CPP) film (ZK93KM film thickness 60 μm manufactured by Toray Industries, Inc.). Evaluation was performed in the same manner as above.

[Volatiles and odor test]
The PET film prints of the inks S1 to S34 (Examples) and SS1 to SS3 (Comparative Examples) obtained in the above Examples and Comparative Examples were cut into a size of 12 cm in width and 22 cm in height immediately after printing, and sealed in a bottle. placed in an oven and held at 60° C. for 12 hours.
The components in the bottle were analyzed by gas chromatography mass spectrometry (GC/MS) in the same manner as above.
(Evaluation criteria)
5: No peak attributed to organic matter was observed, and the printed matter was odorless. (excellent)
4: A peak attributed to an organic substance was confirmed, and the printed material was odorless. (good)
3: A peak attributed to an organic matter was confirmed, and the printed matter had a slight odor. (possible)
2: A peak attributed to organic matter was confirmed, and the printed matter had a slightly strong odor. (impossible)
1: A peak attributed to organic substances was confirmed, and the printed matter had a strong odor. (inferior)
The practical level is 3-5.

[Laminate strength]
An imine-based anchor coating agent (EL420 manufactured by Toyo-Morton Co., Ltd.) was applied onto the printed layer of the printed OPP film of the inks S1 to S34 (Examples) and SS1 to SS3 (Comparative Examples) obtained in the above Examples and Comparative Examples. is coated with a methanol solution having a solid content of 1% by mass, and a molten polyethylene (LC600A, manufactured by Japan Polyethylene Co., Ltd.) is extruded at 320 ° C. at a line speed of 100 m / min by an extrusion laminator (manufactured by Musashino Kikai Co., Ltd.) to laminate at 18 μm. At the same time, CPP (FCMN manufactured by Futamura Chemical Co., Ltd., film thickness: 20 μm) was attached in the same manner to obtain a laminate. After lamination, the laminate was cut into a length of 150 mm and a width of 15 mm, opened at the ink/OPP film interface, and the laminate strength in the 90° direction was measured using a tensile tester.
(Evaluation criteria)
5: 1.5 N/15 mm or more (excellent)
4: 1.0 N/15 mm or more and less than 1.5 N/15 mm (good)
3: 0.8 N/15 mm or more and less than 1.0 N/15 mm (possible)
2: 0.5 N/15 mm or more and less than 0.8 N/15 mm (impossible)
1: less than 0.5N/15mm (poor)
The practical level is 3-5.

From the above results, the object of the present application could be achieved by using the gravure or flexographic ink of the present invention. Also, when a biomass polyurethane resin using a polyester polyol having a biomass-derived dibasic acid was used, an improvement in laminate strength was observed. In addition, the polyurethane resin contains at least one biomass dibasic acid selected from succinic acid, sebacic acid and dimer acid, and a polyester structure composed of a diol containing a branched diol and a linear diol. Excellent results were obtained with respect to the odor of the product and the odor of the printed matter of the present invention.

Claims (5)

A gravure or flexo ink having a binder resin containing a biomass polyurethane resin and a vinyl chloride-acrylic copolymer resin ,
The polyurethane resin contains a structural unit derived from a polyester polyol obtained by condensation reaction of a dibasic acid and a diol, the dibasic acid contains 65% by mass or more of the biomass dibasic acid, and the biomass dibasic Acids include sebacic acid and succinic acid,
The diol includes a branched diol and a linear diol, and the mass ratio (branched diol: linear diol) is 30:70 to 70:30.
gravure or flexographic inks.
(However, the case where the binder resin contains nitrocellulose is excluded.) The gravure or flexo ink according to claim 1, containing 70% by mass or more of biomass dibasic acid in 100% by mass of dibasic acid. The gravure or flexo ink according to claim 1 or 2 , wherein the biomass polyurethane resin has a biomass degree of 40 to 100% by mass. A printed matter having a print layer formed of the gravure or flexo ink according to any one of claims 1 to 3 on a substrate 1. A laminate comprising at least a base material 1, a printed layer made of the gravure or flexo ink according to any one of claims 1 to 3 , and a base material 2 in this order.