JP6973046B2 - Ink set and decorative materials - Google Patents

Description

The present invention relates to an ink set, a printed matter, a laminate and a decorative material for forming a printed layer in a decorative material.

The decorative sheet is a decorative material for the purpose of surface protection, decoration, etc. of an adherend such as a wooden board, and is used as a decorative board by being attached to the surface of the adherend. And this decorative board is used for various building materials, furniture and the like. The decorative sheet is often formed by laminating a base material, a printing layer, and a resin layer, and the printing layer is printed with a pattern such as wood grain by printing ink.

Since the decorative board is often used for a long period of time, various durability such as light resistance, weather resistance, and moisture heat resistance are required. Therefore, if the moisture resistance and weather resistance of the printed layer are insufficient, defects due to peeling may occur. Therefore, it is indispensable to satisfy printability and durability at the same time.

In order to solve the above problems, for example, Patent Document 1 discloses a decorative sheet having a printed layer using a water-based ink containing a urethane resin, but the durability is insufficient. Further, Patent Document 2 discloses a decorative sheet containing a binder resin and a modified polypropylene polymer as a printing layer, but the adhesion to the substrate and the stability of the ink over time are insufficient.

JP-A-2007-196432 Japanese Unexamined Patent Publication No. 2014-08010

The problems to be solved by the present invention are the time-dependent stability of the ink and the printing such as plate fog and blocking resistance for forming the printing layer of the decorative material having excellent moisture and heat resistance, light resistance, and laminating strength. It is to provide an ink set having good suitability.

As a result of diligent research, the present inventors have found that the above problems can be solved by the following ink sets, and have completed the present invention.

That is, the present invention is an ink set composed of an ink and an isocyanate-based curing agent for forming a printing layer in a decorative material having a base material, a printing layer and a resin layer in this order, and the following (1) to (3). ) Satisfying the ink set.
(1) The ink contains a polyurethane resin having a weight average molecular weight of 1000 to 100,000 and an organic solvent.
(2) The polyurethane resin has a hydroxyl value of 1 to 40 mgKOH / g and / or an amine value of 1 to 20 mgKOH / g.
(3) The mass ratio (polyurethane resin / isocyanate-based curing agent) of the polyurethane resin and the isocyanate-based curing agent is 99/1 to 60/40.

The present invention also relates to the ink set, wherein the polyurethane resin has a structural unit derived from at least one polyol selected from the group consisting of a polyether polyol, a polylactone polyol and a polycarbonate polyol.

Further, the present invention is characterized in that the polyurethane resin has a structural unit derived from a polylactone polyol and contains 5 to 35% by mass of a structural unit derived from the polylactone polyol in the total mass of the polyurethane resin. Regarding.

The present invention also relates to the ink set, wherein the polyurethane resin contains a urea bond, and the urea bond concentration in the polyurethane resin is 0.8 to 2.5 mmol / g.

The present invention also relates to a printed matter formed by the above ink set.

The present invention also relates to a laminate having a substrate, a printing layer formed by the ink set, and a resin layer in this order.

INDUSTRIAL APPLICABILITY According to the present invention, an ink set having good ink stability over time and printability such as plate fog and blocking resistance for forming a printing layer of a decorative material having excellent moisture resistance, light resistance, and laminating strength. Can now be provided.

Hereinafter, embodiments of the present invention will be described in detail. The ink set of the present invention is a set of an ink containing a specific polyurethane resin and an organic solvent, and an isocyanate-based curing agent.

<Polyurethane resin>
The ink constituting the ink set of the present invention uses a polyurethane resin as a binder resin. The binder resin is a thermoplastic resin that is soluble in an organic solvent that has a binding function in ink. Examples of the binder resin other than the polyurethane resin include acrylic resin, polyester resin, nitrocellulose resin, vinyl chloride-vinyl acetate copolymer resin and the like. In the present invention, it is preferable to use the polyurethane resin as the main component (50% by mass or more) of the binder resin from the viewpoint of the adhesion between the base material and the resin layer. Further, in order to satisfy the required physical properties, printability, etc., the requirements of the properties (structure, molecular weight, hydroxyl value, amine value, urethane / urea bond concentration, etc.) of the polyurethane resin shown below contribute to the performance.

The weight average molecular weight of the polyurethane resin is 1000 to 100,000, preferably 2000 to 80000. When the weight average molecular weight is 10,000 or more, it is expected that the moisture resistance, the blocking resistance, and the laminating strength are good, and when the weight average molecular weight is 100,000 or less, the plate fog and the ink stability with time are good. Be expected. The weight average molecular weight is a value measured by GPC (gel permeation chromatography).

The polyurethane resin has a hydroxyl value of 1 to 40 mgKOH / g and / or an amine value of 1 to 20 mgKOH / g, preferably a hydroxyl value of 3 to 30 mgKOH / g and / or an amine value of 3 to 15 mgKOH / g. .. When the hydroxyl value is 1 mgKOH / g and / or the amine value is 1 mgKOH / g or more, the moisture resistance and the laminate strength are good, and when the hydroxyl value is 40 mgKOH / g or less and / or the amine value is 20 mgKOH / g or less, the ink It is expected that the stability of the set over time will be good.

The polyurethane resin is not particularly limited, and is a known method described in, for example, JP-A-2002-356529, JP-A-2005-298618, JP-A-2017-19991, JP-A-2016-130297, and the like. Manufactured by. For example, it is obtained by reacting a polyurethane resin obtained by a reaction between a polyol and a polyisocyanate, a urethane prepolymer having an isocyanato group at the terminal obtained by a reaction between a polyol and a polyisocyanate, and an amine-based chain extender such as polyamine. Polyurethane resin or the like is preferable.

The polyurethane resin preferably has a structural unit derived from at least one polyol selected from the group consisting of a polyether polyol, a polylactone polyol and a polycarbonate polyol, and more preferably has a structural unit derived from a polylactone polyol. Further, it is preferable that at least one polyol selected from the group consisting of a polyether polyol, a polylactone polyol and a polycarbonate polyol has 5 to 35% by mass based on the total mass of the polyurethane resin. Further, it is more preferably 10 to 35% by mass. The weather resistance is good when the structural unit derived from the polylactone polyol is 5% or more in the total weight of the polyurethane resin, and the moist heat resistance is good when the structural unit derived from the polylactone polyol is 35% or less in the total mass of the polyurethane resin. be. Examples of other polyols include polyester polyols, polyolefin polyols, castor oil polyols, hydrogenated castor oil polyols, dimer diols, hydrogenated dimer diols and the like.

The polyurethane resin preferably contains a urea bond as well as a urethane bond. The urea bond concentration in the polyurethane resin is preferably 0.8 to 2.5 mmol / g, more preferably 1.2 to 2.0 mmol / g. When the urea bond concentration is 0.8 mmol / g or more, the moisture heat resistance and the blocking resistance are good, and when the urea bond concentration is 2.5 mmol / g or less, the plate fog and the laminate strength are good. The urethane bond concentration and the urea bond concentration refer to the following values. The urethane bond concentration is preferably 1.5 to 2.5 mmol / g.

(Urethane bond concentration)
The urethane bond concentration refers to a value represented by the following formula (1) or formula (2).
When (NCO mole number / OH mole number)> 1.
Formula (1) Urethane bond concentration (mmol / g) = number of moles of OH (mmol) / mass of polyurethane resin (g)
(NCO molar equivalent / OH molar equivalent) <1:
Formula (2) Urethane bond concentration (mmol / g) = NCO molar number (mmol) / mass of polyurethane resin (g)
However, in the formula,
Number of OH moles: Number of moles of hydroxyl groups in the polyol constituting the polyurethane resin Number of moles of NCO: Representing the number of moles of isocyanato groups in the polyisocyanate constituting the polyurethane resin.

(Urea bond concentration)
The urea bond concentration refers to a value represented by the following formula (3) or formula (4).
(NCO molar equivalent / OH molar equivalent)> When a prepolymer having an isocyanate group at the terminal is synthesized under the condition of> 1 and then further reacted with a polyamine to obtain a polyurethane resin having an amino group at the terminal:
Formula (3) Urea bond concentration (mmol / g) = [NCO molar number (mmol) -OH molar number (mmol)] / mass of polyurethane resin (g)
When a prepolymer having an isocyanate group is synthesized under the above condition (NCO molar equivalent / OH molar equivalent)> 1 and then further reacted with a polyamine to obtain a polyurethane resin having an isocyanate group at the terminal:
Formula (4) Urea bond concentration (mmol / g) = (number of moles of amino groups (mmol)) / mass of polyurethane resin (g)
However, in the formula,
Number of OH moles: Number of moles of hydroxyl groups in the polyol constituting the polyurethane resin Number of moles of NCO: Number of moles of isocyanato groups in the polyisocyanate constituting the polyurethane resin Number of moles of amino groups: Number of amino groups in the polyamine constituting the polyurethane resin Represents the number of moles.

Hereinafter, the polyol constituting the polyurethane resin will be described. The polyol refers to a compound having two or more hydroxyl groups in the molecule, and is preferably a polyether polyol, a polylactone polyol, a polycarbonate polyol, an alkane polyol, or the like. The polyol preferably contains a polyol having a molecular weight of less than 500, and preferably contains 5 to 20% by mass in the total mass of the polyol. The polyurethane resin preferably contains 3 to 10% by mass of a structural unit composed of a polyol having a molecular weight of less than 500 in its total mass.

(Polyether polyol)
The above-mentioned polyether polyol is a polyol having an ether bond in its molecular structure and having a hydroxyl group at the terminal due to ring-opening polymerization of cyclic ethers such as ethylene oxide, propylene oxide and tetrahydrofuran, and polycondensation of the polyol. Point to. Among them, polytetramethylene glycol, polypropylene glycol, polyethylene glycol, polytrimethylene glycol and the like are preferable, and the number average molecular weight is preferably 500 to 10000, more preferably 500 to 3000.

(Polylactone polyol)
The polylactone polyol refers to a polyol having a hydroxyl group at the terminal obtained by ring-opening polymerization of the lactone. Polylactone polyols are often synthesized by ring-opening polymerization of lactones in the presence of polyols, but the lactones constituting polylactone polyols include α-acetlactone, β-propiolactone, γ-butyrolactone, and δ. At least one selected from −valerolactone and ε-caprolactone is suitable. The polyol constituting the polylactone polyol is preferably diol, and is preferably ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, or 1,3-butane. Diol, 1,6-hexanediol, 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 and the like are suitable.

Further, when synthesizing a polylactone polyol, a dibasic acid may be used in combination with the above lactone or polyol. Dibasic acids include adipic acid, phthalic acid 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, dimeric acid, hydrogenated dimeric acid and the like.

The polylactone polyol preferably has a number average molecular weight of 500 to 10000, more preferably 500 to 3000. Further, the polyurethane resin preferably contains 5 to 50% by mass of a structural unit composed of a polylactone polyol, more preferably 5 to 35% by mass, and even more preferably 10 to 35% by mass. This is because it is expected that the moisture resistance, the moisture resistance and the hydrolysis resistance will be improved.

(Polycarbonate polyol)
The polycarbonate polyol refers to a polyol having a carbonate structure in the molecule and having a hydroxyl group at the terminal. For example, it is obtained by a dealcohol reaction between a diol and a carbonate. As the diol, the same as above is suitable. Examples of the carbonate which is a monomer constituting the polycarbonate include ethylene carbonate, propylene carbonate, butylene carbonate, 5-methyl-1,3-dioxane-2-one, dimethyl carbonate, diethyl carbonate and the like. The polycarbonate polyol preferably has a number average molecular weight of 500 to 10000, more preferably 500 to 3000.

Specific examples of the polycarbonate polyol include Kuraray polyols C-590, C-1090, C-2050, C-3090 (manufactured by Kuraray Co., Ltd.), ETERNCOLL UH-100, UH-200, UH-300, UM-90, PH-200D (manufactured by Ube Industries, Ltd.) and the like can be mentioned.

(Alkane polyol)
An alkane polyol refers to a compound in which two or more hydrogen atoms of an alkane are substituted with hydroxyl groups. The alkane polyol is preferably alkanediol. The alkane polyol preferably has a molecular weight of less than 500, more preferably 50 to 300. Further, it is preferable that the total mass of the polyols constituting the polyurethane resin is 5 to 20% by mass. Examples of the alkane polyol include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 1,6-hexanediol, 1,8-octanediol, and 1, 9-Nonandiol, 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 and the like can be mentioned. Among them, an alkane polyol having 1 to 6 carbon atoms is preferable, a branched alkane polyol is preferable, an alkane diol is preferable, and the hydroxyl group in the alkane polyol is preferably primary, and the alkane polyol It is preferable to have at least two primary hydroxyl groups, and it is preferable to have an alkyl group having 1 to 4 carbon atoms. Specifically, neopentyl glycol, 3-methyl-1,5-pentanediol and 2-methyl-1,3-propanediol are preferable.

(Polyisocyanate)
Examples of the polyisocyanate constituting the polyurethane resin include various known aromatic diisocyanates, aliphatic diisocyanates, and alicyclic diisocyanates generally used for producing polyurethane resins. For example, 1,5-naphthylenediocyanate, 4,4'-diphenylmethane diisocyanate (MDI), 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-dibenzylisocyanate, 1,3-phenylenediocyanate, 1,4. -Phenylylene diisocyanate, tolylene diisocyanate, butane-1,4-diisocyanate, hexamethylene diisocyanate, isopropylene diisocyanate, methylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, cyclohexane-1,4-diisocyanate, xyl Range isocyanate, Isophoron diisocyanate, Dimeryl diisocyanate, Dicyclohexylmethane-4,4'-diisocyanate, 1,3-bis (isocyanatemethyl) cyclohexane, Methylcyclohexanediisocyanate, Norbornan diisocyanate, m-tetramethylxylylene diisocyanate, 4,4- Examples thereof include diphenylmethane diisocyanate, bis (chloromethyl) diphenylmethane-diisocyanate, 2,6-diisocyanate-benzyl chloride, and dimerized isocyanate obtained by converting the carboxyl group of dimer acid into an isocyanato group. These may be trimers and have an isocyanurate ring structure. These polyisocyanates can be used alone or in admixture of two or more. Of these, aliphatic diisocyanates and alicyclic isocyanates are preferable, and isophorone diisocyanates, hydrogenated xylylene diisocyanates, hexamethylene diisocyanates, and isocyanurates of hexamethylene diisocyanates are preferable.

(Polyamine)
The polyamine constituting the polyurethane resin is not limited as long as it functions as a chain extender and forms a urea bond, but a molecular weight of 500 or less is preferable, and diamines, polyfunctional amines and the like can be mentioned, and the diamine includes ethylenediamine. , Propylene diamine, hexamethylene diamine, pentamethylene diamine, isophorone diamine, dicyclohexylmethane-4,4'-diamine, p-phenylenediamine and the like, preferably 2- (2-aminoethylamino) ethanol, N- (2-hydroxy). Diamines having a hydroxyl group such as propyl) ethylenediamine, N, N'-bis (2-hydroxyethyl) ethylenediamine, and N, N'-bis (2-hydroxyethyl) propylene diamine can also be used. These polyamines can be used alone or in admixture of two or more. By using a diamine having such a hydroxyl group, a hydroxyl group can be introduced into the polyurethane resin. Further, if necessary, a polyamine having three or more amino groups in the molecule can be used as the polyamine, specifically, diethylenetriamine, iminobispropylamine: (IBPA, 3,3'-diaminodipropyl). Amine), triethylenetetramine, N- (3-aminopropyl) butane-1,4-diamine: (spermidine), 6,6-iminodihexylamine, 3,7-diazanonan-1,9-diamine, N, N '-Bis (3-aminopropyl) ethylenediamine can be mentioned. The polyamine is preferably an aliphatic and / or alicyclic amine, and among the above, isophoronediamine, hexamethylenediamine, and iminobispropylamine are preferable.

Further, when synthesizing a polyurethane resin, a monovalent active hydrogen compound can also be used as a polymerization terminator for the purpose of stopping an excessive reaction. Examples of such compounds include monoamines having primary and secondary amino groups, and examples thereof include dialkylamines such as di-n-butylamine and amino alcohols such as 2-ethanolamine and 3-propanolamine. Be done. In particular, when it is desired to introduce a hydroxyl group into a polyurethane resin, it is possible by using amino alcohols as a polymerization inhibitor.

The polyurethane resin having a hydroxyl group can be obtained, for example, by reacting the urethane prepolymer with a diamine having a hydroxyl group such as 2-hydroxyethylethylenediamine or 2-hydroxyethylpropyldiamine, or by using an amino alcohol as the polymerization terminator. The obtained polyurethane resin having an amino group can be obtained, for example, by reacting the above urethane prepolymer with a diamine-based chain extender such as hexamethylenediamine or isophoronediamine. However, the method for introducing a hydroxyl group or an amino group is not limited to these.

<Organic solvent>
The ink set of the present invention contains an organic solvent. The organic solvent is preferably a so-called non-toluene organic solvent that does not contain aromatic organic solvents such as toluene and xylene, and is a ketone organic solvent such as methyl ethyl ketone and methyl isobutyl ketone, ethyl acetate and n-propyl acetate. , Ester-based organic solvents such as isopropyl acetate and isobutyl acetate, alcohol-based organic solvents such as methanol, ethanol, 1-propanol (n-propanol), isopropanol and n-butanol, propylene glycol monomethyl ether, ethylene glycol monoisopropyl ether and the like. Glycol ether-based organic solvents and the like are preferable, and they may be mixed and used. Above all, it is preferable to contain 10% or less of the glycol ether-based organic solvent in the total mass of the ink. Further, water may be contained in a small amount of 10% or less in the total mass of the ink.

<Isocyanate-based curing agent>
The isocyanate-based curing agent is necessary for imparting adhesion to a substrate and a resin layer and imparting moisture and heat resistance in the ink set of the present invention, and a compound having two or more isocyanato groups in one molecule is preferable. It is more preferable to have 2 to 4 isocyanato groups in it.

The isocyanate-based curing agent is not particularly limited, but isocyanurate, trimethylolpropane adduct, burette, allophanate and the like are suitable, and it is preferable to use one or more of them. The isocyanurate form is a trimer in which diisocyanate is cyclized. The adduct body refers to an isocyanate having a structure in which diisocyanate is added to the hydroxyl group of a body having a hydroxyl group such as ethylene glycol, glycerin, and trimethylolpropane. The burette body refers to an isocyanate in which a diisocyanate forms a burette bond with a compound having a urethane bond. The allophanate form refers to an isocyanate in which diisocyanate forms a burette bond with a compound having a urea bond.

Among these isocyanate-based curing agents, examples of the diisocyanate include aromatic diisocyanates, aliphatic diisocyanates, and alicyclic diisocyanates constituting the polyurethane resin.
It is preferably at least one selected from hexamethylene diisocyanate, isocyanurate of isophorone diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, and trimethylolpropane adduct of xylylene diisocyanate.

In the ink set of the present invention, the mass ratio of the polyurethane resin to the isocyanate-based curing agent (polyurethane resin and isocyanate-based curing agent) is 99/1 to 60/40, preferably 90/10 to 70/30. .. When the mass ratio of the polyurethane resin to the isocyanate-based curing agent (polyurethane resin / isocyanate-based curing agent) is 99/1 or less, the moisture heat resistance and the laminate strength are good, and when it is 60/40 or more, the ink stability over time. , Plate fog resistance and blocking resistance are improved. Within the above numerical range, the hydroxyl group and / or amino group of the polyurethane resin and the isocyanate-based curing agent form a urethane bond or a urea bond, so that the cohesive force of the printed layer is improved.

<Colorant>
The ink may contain a colorant. Examples of the colorant include pigments and dyes, and the pigment can be either an inorganic pigment or an organic pigment. Organic pigments include soluble azo, insoluble azo, azo, phthalocyanine, halogenated phthalocyanine, anthraquinone, anthraquinone, dianthraquinonyl, anthrapyrimidine, perylene, perinone, quinacridone, etc. Pigments such as thioindigo-based, dioxazine-based, isoindoline-based, quinophthalone-based, azomethine-azo-based, flavanthron-based, diketopyrrolopyrrole-based, isoindoline-based, indanslon-based, and carbon black-based pigments can be mentioned.

On the other hand, examples of the inorganic pigment include white inorganic pigments such as titanium oxide, zinc oxide, zinc sulfide, barium sulfate, calcium carbonate, chromium oxide, and silica. Among the inorganic pigments, the use of titanium oxide is particularly preferable. Titanium oxide is white and is preferable from the viewpoints of coloring power, hiding power, chemical resistance and weather resistance, and is preferably treated with silica and / or alumina from the viewpoint of printing performance. Examples of inorganic pigments other than white include aluminum particles, mica (mica), bronze powder, chrome vermillion, chrome yellow, cadmium yellow, cadmium red, ultramarine, dark blue, red iron oxide, yellow iron oxide, iron black, zinc oxide and the like. Can be mentioned.

The pigment is in an amount sufficient to secure the concentration and coloring power of the ink, that is, 1 to 50% by weight with respect to the total weight of the ink composition, and 10 to 90% by weight in terms of the solid content weight ratio in the ink composition. It is preferably contained in proportion. In addition, these pigments can be used alone or in combination of two or more.

<Additives>
Inks are general inks such as pigment derivatives, extender pigments, dispersants, wetting agents, adhesive aids, leveling agents, defoaming agents, antistatic agents, trapping agents, blocking inhibitors, wax components, and silane coupling agents. Can contain the additives used in. For example, as the dispersant, anionic, nonionic, cationic, amphoteric or the like surfactants can be used. From the viewpoint of storage stability of the ink, the dispersant is preferably contained in the ink in an amount of 0.1 to 10.0% by weight based on 100% by weight of the total weight of the ink. Further, it is more preferably contained in the range of 0.1 to 3.0% by weight.

<Manufacturing of ink>
The ink can be produced by dissolving and / or dispersing a polyurethane resin or the like in an organic solvent. Specifically, for example, an ink can be produced by mixing a polyurethane resin and, if necessary, the colorant and the dispersant, and adding an organic solvent and the like. As the disperser, generally used, for example, a roller mill, a ball mill, a pebble mill, an attritor, a sand mill and the like can be preferably used.

<Viscosity>
The viscosity of the ink is in the viscosity range of 40 to 500 mPa · s at 25 ° C. with a B-type viscometer in order to support high-speed printing (50 to 300 m / min) in flexographic printing methods and gravure printing methods. Is preferable. More preferably, it is in the range of 50 to 400 mPa · s. In this viscosity range, the viscosity in Zahn Cup # 4 corresponds to about 9 to 40 seconds. The viscosity of the ink can be adjusted by appropriately selecting the type and amount of the raw material used, for example, the amount of the polyurethane resin, the organic solvent, and the like.

<Base material>
The base material used in the present invention is mainly in the form of a film or a sheet. The material constituting the base material is not limited, but a resin base material (plastic base material) is preferably used. The types of resins constituting the resin base material include polyolefin resins such as polyethylene and polypropylene, polyester resins such as polyethylene terephthalate and polylactic acid, polycarbonate resins, acrylic resins such as polymethylmethacrylate, 6-nylon, 6,6. -Polyamide resin such as nylon, cellulose acetate, cellulose propionate, cellulose resin such as nitrocellulose, chlorinated polyolefin resin such as polyvinyl chloride and polyvinylidene chloride, fluoropolyolefin resin such as polytetrafluoroethylene and polyvinylidene fluoride. , Polystyrene resin, AS resin, ABS resin and the like. Further, the ink set of the present invention can be suitably used for a colored substrate. The colored base material is generally obtained by kneading a colorant with the above resin and processing it into a film or a sheet. It should be noted that the transparent substrate may have a colored layer. Further, the surface of the base material may be subjected to surface treatment such as plasma treatment, corona treatment, frame treatment, and primer treatment.

<Print layer>
The ink set of the present invention can be printed by a rotary printing method such as a gravure printing method or a flexographic printing method. For example, it is diluted with an organic solvent to a viscosity and concentration suitable for gravure printing and supplied to each printing unit alone or mixed. A printed matter can be obtained by printing on a substrate using the ink set of the present invention to form a printed layer.

<Resin layer>
As the resin layer, the same resin as the resin constituting the resin base material described above can be used, but it is preferably a layer made of a thermoplastic resin (thermoplastic resin layer). Examples of the thermoplastic resin layer include polyolefin resins such as polypropylene resin and polyethylene resin, polyethylene terephthalate resin, polyvinyl chloride resin, and resins made of polymers of acrylic, styrene, and other monomers. These resins may be one kind of resin or two or more kinds of resins. Further, the resin layer may be a single layer or a layer composed of a plurality of layers.

<Laminated body>
In the laminate of the present invention, the base material, the printing layer composed of the ink set of the present invention, and the resin layer are arranged in this order. The laminate of the present invention is, for example, a direct laminating method in which molten polypropylene or the like is pressure-bonded to a printing layer and laminated, a doubling method in which a vinyl chloride resin sheet or the like is thermally pressure-bonded to a printing layer and laminated, and molten polyethylene is laminated on a printing layer. It can be obtained by a known method such as an extrusion laminating method in which a resin, a molten polypropylene resin, or the like is laminated. An anchor coat layer may be provided in order to improve the adhesion between the layers in the laminated body. Examples of the anchor coat layer include a layer made of an anchor coating agent such as imine-based, isocyanate-based, and polybutadiene-based. In the laminated body, it is preferable to use it between the printed layer and another layer.

<Cosmetic material>
The decorative material of the present invention is obtained by laminating the above-mentioned laminate and a board. Examples of the board include wooden plates, plastic boards, metal boards and composite boards thereof, and more specifically, South Sea plywood, particle board, medium density fiberboard (hereinafter MDF), Japanese agriculture and forestry standards. Examples thereof include specified ordinary plywood, a base material made of wood powder-added olefin resin, a steel plate, an aluminum plate, and a composite plate thereof. An adhesive or the like may be used when the laminate and the board are bonded together. The thickness of the plate is preferably about 3 to 25 mm.

Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples. In addition, "part" and "%" in this invention represent "part by mass" and "% by mass" unless otherwise noted. In addition, Examples 7, 9, 23, 25 are reference examples.

(Hydroxy group value)
The hydroxyl value was measured based on the method specified in JIS K0070 (1992).

(Amine value)
The amine value was measured by the following method. A sample was precisely weighed in an amount of 0.5 to 2 g (sample amount: Sg). To the weighed sample, 30 mL of neutral ethanol (BDG neutral) was added and dissolved. 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 set as the end point, and the amine titer was determined from the titration amount (AmL) at this time based on the following (formula 2).
(Equation 5) Amine value = (A × f × 0.2 × 56.108) / S

(Number average molecular weight (Mn))
The number average molecular weight of the polyol was a value obtained from the following formula (6) from the number of hydroxyl groups and the hydroxyl value.
(Equation 6) Number average molecular weight = 56110 x number of hydroxyl groups (pieces) / hydroxyl value (mgKOH / g)
In the formula, the number of hydroxyl groups means the number of hydroxyl groups in one molecule of the polyol, and the hydroxyl value means the value measured by JISK0070 (1992). Units are shown in parentheses.

(Weight average molecular weight (Mw))
Mw was determined as a polystyrene-equivalent molecular weight by measuring the molecular weight distribution using a GPC (gel permeation chromatography) device (“ShodexGPCSystem-21” manufactured by Showa Denko KK). The measurement conditions are shown below.
Column: Use the following multiple columns connected in series.
Made by Tosoh Corporation, TSKgelSuperAW2500,
Made by Tosoh Corporation, TSKgelSuperAW3000,
Made by Tosoh Corporation, TSKgelSuperAW4000,
Made by Tosoh Corporation, TSKgelgrudcolumnSuperAWH
Detector: RI (Differential Refractometer)
Measurement conditions: Column temperature 40 ° C,
Eluent: Tetrahydrofuran Flow rate: 1.0 mL / min

(Synthesis Example 1) [Polyurethane Resin PU1]
50 parts of polycaprolactone diol having a number average molecular weight of 1250, 50 parts of polytetramethylene glycol (hereinafter "PTG") having a number average molecular weight of 2000, 19 parts of neopentyl glycol, isophorone diisocyanate (hereinafter "" The mixture consisting of 99 parts of IPDI) and 54.5 parts of ethyl acetate was reacted at 80 ° C. under a nitrogen stream for 4 hours to obtain a solvent solution of the terminal isocyanate prepolymer. Next, 17.5 parts of isophoronediamine (hereinafter "IPDA"), 2.6 parts of dibutylamine (hereinafter "DBA"), 10.2 parts of 2-hydroxyethylethylenediamine (hereinafter "AEA"), 303.3 parts of ethyl acetate. To the mixture consisting of and isopropanol, the terminal isocyanate prepolymer solution obtained above was gradually added at 40 ° C., and further reacted at 80 ° C. for 1 hour to obtain a solid content of 30%, an amine value of 7.0 mgKOH / g, and a hydroxyl value. A polyurethane resin PU1 solution having 22.1 mgKOH / g and a weight average molecular weight of 40,000 was obtained (the solvent composition in the solution is ethyl acetate / 2-propanol (IPA) = 60/40 (mass ratio)). When the urea bond concentration was calculated based on the above formula (3), it was 1.59 mmol / g.

(Synthesis Examples 2 to 12) [Polyurethane Resin PU2 to PU12]
Polyurethane resin PU2-PU12 solutions were obtained by the same method as in Synthesis Example 1 except that the raw materials and formulations shown in Table 1 were changed. The numerical values in the table represent "parts" unless otherwise specified, and blanks indicate that they are not mixed. Moreover, the blending amount of the solvent is omitted. The abbreviations in the table indicate the following.
Polycarbonate polyol: Polycarbonate diol polyester polyol having a number average molecular weight of 2000 having a structural unit derived from C-20503-methyl-1,5-pentanediol and 1,6-hexanediol manufactured by Claret: Adipic acid and 1,2. -A polyester polyol with a number average molecular weight of 1630, which is a condensate of propanediol.

(Comparative Synthesis Examples 1 to 6) [Polyurethane Resins PU13 to PU18]
Polyurethane resin solutions PU13 to PU18 were obtained by the same method as in Synthesis Example 1 except that the raw materials and formulations shown in Table 2 were changed.

(Example 1) [Creation of ink set S1]
50 parts of polyurethane resin PU1 solution (solid content 30%) as polyurethane resin, C.I. I. 7 parts of Pigment Yellow 110 (BASF, Irgazine Yellow L2060) and 42 parts of a solution of ethyl acetate / IPA = 60/40 (mass ratio) as an organic solvent were mixed, dispersed in an Eiger mill for 30 minutes, and then further organic. An ink was obtained by mixing 1 part of propylene glycol monomethyl ether as a solvent.
Ink set S1 was prepared by using 5 parts of Takenate D-140N (Mitsui Chemicals, Inc., trimethylolpropane adduct of isophorone diisocyanate) as an isocyanate-based curing agent.

(Examples 2 to 16) [Preparation of ink sets S2 to 16]
Ink sets S2 to S16 were obtained by mixing in the same manner as in Example 1 except that the raw materials and formulations shown in Table 3 were changed. The abbreviations in the table indicate the following.
Duranate P301-75E: Trimethylolpropane adduct body of hexamethylene diisocyanate manufactured by Asahi Kasei Corporation Titanium oxide: manufactured by TAYCA Corporation, JR-805

(Comparative Examples 1 to 8) [Creation of Ink Set T1 to 8]
Ink sets T1 to T8 were obtained by the same method as in Example 1 above, except that the raw materials and formulations shown in Table 4 were changed.

(Example 17)
<Printing of ink set>
The ink set S1 obtained above is subjected to a viscosity of 16 seconds (25 ° C., Zahn cup) by a mixed solvent (methyl ethyl ketone "MEK": n-propyl acetate "NPAC": IPA = 40: 40: 20 (mass ratio)). A 60 μm-thick colored (white) polypropylene resin group that has been diluted and mixed so as to be No. 3) and corona-treated with a Helio 175-line gradation plate (plate type compressed, 100% to 3% gradation pattern). Printing was performed on the corona-treated surface of the material at a printing speed of 150 m / min to obtain a printed matter G1. After the printing was completed, the plate was idled for 60 minutes to confirm the plate fogability.

<Heat laminate>
With respect to the obtained printed matter G1, the printed layer of the printed matter G1 and unstretched transparent polyethylene (TUXFCD 100 μm manufactured by Mitsui Chemicals Tohcello Co., Ltd.) were heat-laminated at 80 ° C. to obtain a heat-laminated laminate A1.

<Extrusion (EL) Laminate>
A urethane resin-based anchor coating agent (EL540 (main agent) / CAT-RT32 (curing agent) manufactured by Toyo Morton Co., Ltd.) is added to the printed layer of the printed matter G1 with a solid content of 1% by weight (weight ratio, methanol / water = 70/30). It is coated with a solution and dried, and then low-density polyethylene (Novatec LC600, manufactured by Japan Polychem Corporation) is melted at 315 ° C. and laminated (extrusion laminating) to obtain an EL laminated laminate B1. rice field.

(Examples 18 to 32)
Using the ink sets S18 to S32, printed matter G2 to G16, heat laminated laminates A2 to A16, and EL laminated laminates B2 to B16 were obtained in the same manner as in Example 17.

(Comparative Examples 9 to 16)
The ink sets T1 to T8 were laminated in the same manner as in Example 16 to obtain printed matter H1 to H8, thermal laminated laminates C1 to C8, and EL laminated laminates D1 to D8, respectively. The evaluation was performed after holding the laminated laminate at 40 ° C. for 48 hours.

The ink sets, printed matter, and laminated laminates obtained above were evaluated as follows, and the results are shown in Table 5 (Example) and Table 6 (Comparative Example).

<Moisture and heat resistance>
The heat-laminated laminates A1 to 16 (Example) and C1 to C8 (Comparative Example) were stored at 85 ° C. and 85% RH for 1 month. The laminates before and after storage were each cut to a width of 15 mm, and the peel strength (laminate strength) between the printed layer and the substrate was measured with an Intesco 2.01 universal tensile tester. Moisture heat resistance was evaluated by the ratio of the laminate strength after storage to the laminate strength before storage. The laminate strength of the heat-laminated laminates A1 to 16 before storage was 10 N / 15 mm or more, which satisfied the practical level.
A. No decrease in laminate strength is observed. (Very good)
B. It is 85% or more and less than 100% of the pre-storage laminate strength. (Good)
C. 70% or more and less than 85% of the pre-storage laminate strength. (Within practical range)
D. It is 40% or more and less than 70% of the pre-storage laminate strength. (Defective)
E. Less than 40% of pre-storage laminate strength. (Extremely bad)

<Light resistance>
For the heat laminated laminates A1 to 16 (Example) and C1 to C8 (Comparative Example), using an accelerated light resistance tester ultraviolet fade meter (manufactured by Suga Test Instruments Co., Ltd.), 63 ° C., 50% RH, illuminance 450 W / Light was irradiated for 96 hours under m ^{2 conditions.} The laminates before and after irradiation were each cut to a width of 15 mm, and the peel strength (laminate strength) between the printed layer and the substrate was measured with an Intesco 2.01 universal tensile tester. The laminating strength of the thermal laminated laminates A1 to 16 before light irradiation was 10 N / 15 mm or more, which satisfied the practical level.
A. No decrease in laminate strength is observed. (Very good)
B. It is 85% or more and less than 100% of the pre-storage laminate strength. (Good)
C. 70% or more and less than 85% of the pre-storage laminate strength. (Within practical range)
D. It is 40% or more and less than 70% of the pre-storage laminate strength. (Defective)
E. Less than 40% of pre-storage laminate strength. (Extremely bad)

<Ink set stability over time>
The viscosities of the ink sets S1 to S16 (Example) and T1 to T8 (Comparative Example) are increased by the mixed solvent (methyl ethyl ketone "MEK": n-propyl acetate "NPAC": isopropanol "IPA" = 40: 40: 20). After diluting and mixing for 16 seconds (25 ° C, Zahn cup No. 3), storage was performed at 25 ° C for 24 hours. The viscosities before and after storage were measured, and the stability of the ink set over time was evaluated from the difference in viscosity before and after storage. The viscosity was measured at 25 ° C. It was performed in 3 outflow seconds.
A. No change in viscosity (extremely good)
B. Viscosity difference exceeds 0 seconds and is 2 seconds or less (good)
C. Viscosity difference exceeds 2 seconds and is 5 seconds or less (within practical range)
D. Viscosity difference exceeds 5 seconds and is 10 seconds or less (defective)
E. Viscosity difference exceeds 10 seconds (extremely defective)

<Plate coverability>
The ink sets S1 to S15 (Examples) and T1 to T8 (Comparative Examples) were evaluated for plate fog. The evaluation was performed based on the colored area on the gravure plate after idling speed of 150 m / min and idling 60 minutes. The doctor blade was made of ceramic.
A. No plate fog is recognized. (Very good)
B. The plate covering area is 0% or more and less than 5%. (Good)
C. The plate covering area is 5% or more and less than 10%. (Within practical range)
D. The plate covering area is 10% or more and less than 30%. (Defective)
E. The plate covering area is 30% or more. (Extremely bad)

<Blocking resistance>
Printed matter G1 to G15 (Example) and H1 to H8 (Comparative Example) were cut into a size of 4 cm × 4 cm, and the colored polypropylene resin base materials used in the above Example 17 were cut into the same size and overlapped with each other at 5 kg / /. After ^{applying a cm 2} load and allowing it to stand for 24 hours in an atmosphere of 40 ° C. and 80% humidity, the printed surface and the film were peeled off, and the degree of ink film removal was visually determined.
A. Ink film does not peel off at all. (Very good)
B. Ink film peels off by 0% or more and less than 5%. (Good)
C. Ink film peels off by 5% or more and less than 10%. (Within practical range)
D. Ink film peels off by 10% or more and less than 30%. (Defective)
E. Ink film peels off by 30% or more, or sticks to the entire surface and cannot be peeled off. (Extremely bad)

<Laminate strength>
The EL laminated laminates B1 to B16 (Example) and D1 to D8 (Comparative Example) are each cut to a width of 15 mm and peeled off at the ink film surface and the resin layer, and then the peel strength (laminate strength) is determined by Intesco 201. Measured with a universal tensile tester. The practical level is 10 N / 15 mm or more.

From the evaluation results, it was found that the present invention is an ink set having excellent moisture and heat resistance and weather resistance, good ink stability over time, printability such as plate fog and blocking resistance, and laminating strength. Further, when a decorative material was produced using the laminate prepared in the above example, all of them were decorative materials having good moisture and heat resistance and weather resistance.

Claims (5)

An ink set composed of an ink and an isocyanate-based curing agent for forming a printing layer in a decorative material having a base material, a printing layer, and a resin layer in this order, which is characterized by satisfying the following (1) to (3). Ink set.
(1) The ink contains a polyurethane resin having a weight average molecular weight of 1000 to 100,000 and an organic solvent.
(2) The polyurethane resin has a hydroxyl value of 1 to 40 mgKOH / g and / or an amine value of 1 to 20 mgKOH / g.
(3) The mass ratio of the polyurethane resin to the isocyanate-based curing agent (polyurethane resin / isocyanate-based curing agent) is 99/1 to 60/40.
(4) The polyurethane resin contains a structural unit derived from a polylactone polyol, and has 5 to 35% by mass of a structural unit derived from the polylactone polyol in the total mass of the polyurethane resin. The polyurethane resin contains a urea bond, a urea bond concentration of the polyurethane resin is, ink set according to claim 1, characterized in that the 0.8~2.5mmol / g. A printed matter formed by the ink set according to claim 1 or 2. A laminate having a base material, a printing layer formed by the ink set according to claim 1 or 2, and a resin layer in this order. A decorative material comprising the laminate according to claim 4.