JP2020196855A - Organic solvent-based printing ink having desorption capability, printed matter and laminate - Google Patents

Abstract

To provide organic solvent-based printing ink which can desorb ink from a plastic film with an alkali aqueous solution in a laminate having good printing processing suitability and surface printing constitution and laminate constitution, and expresses good retort suitability in the laminate having the laminate constitution.SOLUTION: Organic solvent-based printing ink for forming a desorption layer having desorption capability from a base material contains a polyurethane resin having an acid value of 15-70 mgKOH/g and a hydroxyl value of 1-35 mgKOH/g as a binder resin.SELECTED DRAWING: None

Description

The present invention relates to an organic solvent-based printing ink having a desorbing ability, and a printed matter and a laminate using the same.

In recent years, packages made from plastic films, plastic bottles and other plastic products have been disposed of and dumped as garbage in the ocean, which has become a problem of environmental pollution. These plastic products are decomposed into submicron-sized fragments (microplastics) in seawater and float in seawater. When the plastic is ingested by marine organisms such as fish, it is concentrated in the organism. Then, there is a concern that it will affect the health of seabirds and humans who ingest the marine organisms as food.
In the case of a laminated package as described below, ink, adhesives, and harmful substances caused by the coating layer are also attached to the surface of the microplastic, which is a concern from the viewpoint of environmental protection. There is. Various efforts have begun to reduce microplastics to remedy these problems.

The above-mentioned plastic products mainly include food packaging packages using a plastic base material. In the package, various plastic base materials such as polyester base material (PET), nylon base material (NY), and polypropylene base material (OPP) are used as the film base material. A pattern layer is applied to these with gravure ink, flexographic ink, or other printing ink, and the laminate is further bonded to a hot-melt resin base material via an adhesive or the like to form a (laminated) laminate, and then the laminate is cut. It is heat-sealed to form a package. As the package form, there are a form in which the pattern layer is the outermost layer of the package (called front printing) and a form in which the pattern layer exists as an intermediate layer between the base materials (called laminate or back printing).
It should be noted that the front printing corresponds to the front printing even in a form in which the base material or the like is not laminated on the pattern layer and the pattern layer is exposed, for example, a form used for a label or the like.

As an attempt to reduce the amount of microplastics, in the above package, (1) the plastic base material is replaced with paper, and (2) the plastic base material is limited to the use of only the same type to simplify recycling (referred to as monomaterialization). , (3) Remove impurities and recycle plastic.

In the above (1), if paper is used as a raw material, it is promising in terms of safety and recyclability, but it becomes a problem because it is inferior in gas barrier property and water resistance as compared with a plastic base material. Although studies are being conducted on coating agents for paper, there are high hurdles for practical use. The above (2) is an attempt to recycle a plastic base material by forming a package with only a polyolefin base material such as polypropylene. However, there is a problem that the polyolefin base material cannot obtain the performance in the usage form that requires high functionality such as retort resistance and light shielding property. Therefore, the technology development for (3) above has been carried out after comprehensively considering the efficiency of recycling and the performance of the package.

As the above (3), an attempt has been made to remove the pattern layer (front printing ink layer) on the outer surface of the package, which becomes an impurity in the process of recycling the plastic base material, with an alkaline aqueous solution. For example, Cited Document 1 discloses a technique in which an undercoat layer made of an acrylic resin or a styrene-maleic acid-based resin is provided on a plastic base material, and the front print layer arranged on the undercoat layer is removed with alkaline water. .. Further, Patent Document 2 discloses a technique in which an ink using a polyurethane resin having an acidic group or an acrylic resin as a binder resin is printed on the surface, and the printing layer is removed with alkaline water. However, these are techniques that only remove the front printing ink on the outside of the package, and have not yet removed the ink layer in the laminated laminate and peeled the base materials from each other.

In addition to removing the front printing ink layer for plastic recycling, the technology for removing the ink layer in the laminated laminate is an important technology that can be industrially used for environmental protection in promoting plastic recycling. However, the technology that can achieve both of these has not yet been reported.

Japanese Unexamined Patent Publication No. 2001-131484 JP-A-11-209677

INDUSTRIAL APPLICABILITY The present invention has good print processing suitability, can desorb ink and the like from a plastic film with an alkaline aqueous solution in a laminate having a front printing structure and a laminated structure, and has a good retort in the laminated laminate. An object of the present invention is to provide an organic solvent-based printing ink that exhibits aptitude.

As a result of diligent research on the subject of the present invention, the present inventor has found that the problem can be solved by using the organic solvent-based printing ink described below, and has achieved the present invention.

That is, one embodiment of the present invention is
An organic solvent-based printing ink for forming a desorbing layer having a desorbing ability from a base material.
The printing ink relates to an organic solvent-based printing ink containing a polyurethane resin having an acid value of 15 to 70 mgKOH / g and a hydroxyl value of 1 to 35 mgKOH / g as a binder resin.

Another embodiment of the present invention relates to the organic solvent-based printing ink, wherein the polyurethane resin contains a constituent unit derived from a polyol, and the polyol contains 5 to 100% by mass of a polyester polyol.

Another embodiment of the present invention is an organic solvent-based printing ink for forming a desorbing layer having a desorbing ability from a substrate.
The printing ink contains a polyurethane resin having an acid value of 15 to 70 mgKOH / g as a binder resin, and the polyurethane resin contains a constituent unit derived from a polyol.
The polyol relates to an organic solvent-based printing ink containing 50% by mass or more of a polyester polyol having an ester bond concentration of 4 to 11 mmol / g.

Another embodiment of the present invention relates to the organic solvent-based printing ink according to any one of the above, wherein the polyurethane resin has a molecular weight distribution (Mw / Mn) of 6 or less.

According to any of the above, in another embodiment of the present invention, the polyurethane resin contains a constituent unit derived from a polyol, and the polyol contains 70% by mass or more of a polyester polyol having an ester bond concentration of 7 to 11 mmol / g. Regarding organic solvent-based printing inks.

In another embodiment of the present invention, the organic solvent-based printing according to any one of the above, wherein the polyurethane resin has an acid value of 20 to 50 mgKOH / g and a hydroxyl value of 10 to 30 mgKOH / g. Regarding ink.

In another embodiment of the present invention, the polyester polyol is a condensate of a dibasic acid having carboxyl groups at both ends of the alkylene group (R ¹ ) and a diol having hydroxyl groups at both ends of the alkylene group (R ² ). Yes,
Either the number of carbon atoms that linearly connects the carboxyl groups of the dibasic acid or the number of carbon atoms that linearly connects the hydroxyl groups of the diol has 1 to 6 carbon atoms.
The organic solvent-based printing ink according to any one of the above, wherein the alkylene groups (R ¹ ) and (R ² ) are substituted or unsubstituted alkylene groups.

Another embodiment of the present invention relates to a printed matter having a desorption layer composed of the organic solvent-based printing ink according to any one of the above on the base material 1.

Another embodiment of the present invention relates to a laminate having at least a base material 1, a desorption layer made of the organic solvent-based printing ink according to any one of the above, and a base material 2.

Another embodiment of the present invention is a method for producing a recycled base material, which comprises a step of immersing a printed matter in a basic aqueous solution.
The printed matter has a base material 1, a desorption layer formed by the organic solvent-based printing ink according to any one of the above, and a pattern layer in this order.
The present invention relates to a method for producing a recycled base material, wherein the basic aqueous solution contains 0.5 to 10% by mass of the total basic aqueous solution, and the water temperature of the basic aqueous solution at the time of immersion is 30 to 120 ° C.

Another embodiment of the present invention is a method for producing a recycled base material, which comprises a step of immersing the laminate in a basic aqueous solution.
The laminate has a desorption layer formed by the organic solvent-based printing ink according to any one of the above, and a pattern layer and / or an adhesive layer between the base material 1 and the base material 2. ,
The present invention relates to a method for producing a recycled base material, wherein the basic aqueous solution contains 0.5 to 10% by mass of the total basic aqueous solution, and the water temperature of the basic aqueous solution at the time of immersion is 30 to 120 ° C.

By using the organic solvent-based printing ink of the embodiment of the present invention, the ink and the like can be desorbed from the plastic film by the alkaline aqueous solution in the laminated body having the front printing structure and the laminated structure, and the laminated laminated body can be used. It is possible to provide an organic solvent-based printing ink that exhibits good retort suitability.

The embodiments of the present invention will be described in detail below, but the description of the embodiments or requirements described below is an example of the embodiments of the present invention, and the present invention is limited to these contents as long as the gist thereof is not exceeded. Not done.

In the following description, "organic solvent-based printing ink" may be simply abbreviated as "printing ink" or "ink", but they have the same meaning. Further, the layer formed from the organic solvent-based printing ink is the same as the "desorption layer having the ability to desorb from the base material", and may be simply referred to as the "desorption layer" or the "ink layer". Is. On the other hand, a printing ink that is not directly printed on the substrate and does not affect the desorption function is referred to as a "pattern ink", and the printing layer is referred to as a "pattern ink layer" or a "pattern layer".

Embodiment 1 in the present invention is an organic solvent-based printing ink for forming a desorbing layer having a desorbing ability from a base material, and the printing ink has an acid value of 15 to 70 mgKOH / g as a binder resin. It is an organic solvent-based printing ink containing a polyurethane resin having a hydroxyl value of 1 to 35 mgKOH / g. When the polyurethane resin has an acid value of 15 mgKOH / g or more and a hydroxyl value of 1 mgKOH / g or more, the ink layer is removed from the alkaline aqueous solution due to the interaction between the hydrophilicity of the hydroxyl group and the neutralization of the alkali by the acid value. It will be easier. When the acid value is 70 mgKOH / g or less and the hydroxyl value is 35 mgKOH / g or less, the adhesion to the plastic film and the water resistance are good, and as a result, the retort resistance is good.

Further, the second embodiment in the present invention is an organic solvent-based printing ink for forming a desorbing layer having a desorbing ability from a base material, and the printing ink has an acid value of 15 to 70 mgKOH / g as a binder resin. Polyurethane resin is contained, the polyurethane resin contains a constituent unit derived from a polyol, and the polyol is an organic solvent system containing 50% by mass or more of a polyester polyol having an ester bond concentration of 4 to 11 mmol / g in the total weight of the polyol. Printing ink. The predetermined acid value range has the same effect as described above, and further, by using 50% by mass or more of the polyester polyol having an ester bond concentration of 4 to 11 mmol / g, the water resolution of the polyester polyol also contributes and the ink layer is eliminated. It encourages more.

However, the organic solvent-based printing ink excludes the case where the acid value of the polyurethane resin is neutralized in the ink.

The above-mentioned "desorption" means desorption by neutralization / dissolution with a basic aqueous solution (alkaline aqueous solution). The basic substance used in the basic aqueous solution is not particularly limited, but sodium hydroxide (NaOH), potassium hydroxide (KOH), calcium hydroxide (Ca (OH) ₂ ), ammonia, barium hydroxide (Ba (Ba) OH) ₂ ), sodium carbonate (Na ₂ CO ₃ ) and the like are preferably mentioned. It is preferably NaOH and / or KOH. However, the form of the desorption condition of the present invention is not limited to these. The desorption includes both a case where the desorbed layer is melted and peeled off from the base material and a case where the desorbed layer is peeled off without being dissolved.

It is the desorption layer that is desorbed from the base material with the alkaline aqueous solution, but the pattern layer, the adhesive layer, the base material that does not come into contact with the desorption layer, etc., which will be described later, are desorbed as the desorption layer is desorbed. Including cases.
"Having the ability to desorb from the base material" does not mean that the layer desorbed from the base material is a part of the desorbed layer. An object of the present invention is to obtain a desorbed base material as a recycled base material / recycled base material, and it is preferable to remove as many desorbed layers, pattern layers and other layers as possible from the base material. Specifically, out of 100% by mass of the desorbed layer, at least 50% by mass or more of the desorbed layer is desorbed in the area and film thickness direction. It is preferably used in a mode of removing 60% by mass or more, more preferably 80% by mass or more, and further preferably 90% by mass or more.

The desorbed layer is provided for the purpose of obtaining a regenerated base material. Therefore, in the case of solder resist or color resist, there is a step of dissolving a part of the layer with an alkaline aqueous solution, but the purpose of the cured layer with active energy rays is to leave a certain amount even after the alkaline aqueous solution treatment. , The technical idea is different from the desorption layer in the present invention. Therefore, the desorbed layer in the present invention excludes the case where it is a layer made of a solder resist, a color resist or other photosensitive resin composition.

As a mechanism of desorption, it is presumed that in a laminated laminate containing a desorption layer (for example, a mode such as base material 1 / desorption layer / base material 2), an alkaline aqueous solution is generated from the gap between the base materials. It is conceivable that it permeates and comes into contact with the desorbed layer, and is desorbed from the base material by dissolving the desorbed layer or the like. It is preferable to carry out the desorption step in a form having a desorption layer on the cross section. Here, in the laminated laminate or the packaging bag using the same, even if there is no gap for the alkaline aqueous solution to permeate, it is sufficient that the laminate is cut in the desorption step and the cross section has the desorbed layer.
On the other hand, in a printed matter having a printed layer including a desorbed layer (for example, a mode such as a base material 1 / desorbed layer / a pattern layer), an alkaline aqueous solution permeates the pattern layer and contacts the desorbed layer in addition to the cross section. Therefore, it can be detached without any limitation on the cross section. However, in either form of the printed matter or the laminated laminate, it is preferable that the printed matter is cut and desorbed.

(Desorption layer)
The desorption layer in the embodiment of the present invention is formed from the organic solvent-based printing ink described below. First, a polyurethane resin contained as a binder resin in an organic solvent-based printing ink will be described. The binder resin refers to a main resin component for forming a desorbed layer. The "main" means that it is 50% by mass or more of the total amount of the resin components constituting the desorbed layer.

<Polyurethane resin>
In the first embodiment of the present invention, the polyurethane resin used for the organic solvent-based printing ink has an acid value of 15 to 70 mgKOH / g and a hydroxyl value of 1 to 35 mgKOH / g. Further, in the second embodiment of the present invention, the acid value is 15 to 70 mgKOH / g, and the ester bond concentration and the like are specified.
The acid value is a value obtained by converting the amount of acid in 1 g of the resin calculated by titrating the acid with an alkali into the number of mg of potassium hydroxide. The hydroxyl value is a value obtained by converting the amount of hydroxyl groups in 1 g of the resin calculated by esterifying or acetylating the hydroxyl groups in the resin and back titrating the remaining acid with an alkali into mg number of potassium hydroxide. Both the acid value and the hydroxyl value are values obtained according to JIS K0070. From the viewpoint of the balance between the desorption property by the alkaline aqueous solution and the retort resistance, the polyurethane resin preferably has an acid value of 20 to 50 mgKOH / g, and more preferably 25 to 40 mgKOH / g. Further, the hydroxyl value is preferably 10 to 30 mgKOH / g, and the hydroxyl value is still more preferably 15 to 27 mgKOH / g.

The molecular weight distribution (Mw / Mn) of the polyurethane resin is preferably 6 or less. Mw represents a weight average molecular weight, and Mn represents a number average molecular weight. When Mw / Mn is 6 or less, the influence caused by the excessive high molecular weight component, the unreacted component, the side reaction component and other low molecular weight components can be avoided, and the detachability, drying property and retort resistance are suitable. Becomes good. Further, when the molecular weight distribution is smaller (the molecular weight distribution is sharp), the action of uniform contact with the alkaline aqueous solution is exerted, and the desorption property by the alkali becomes better. The molecular weight distribution is still more preferably 5 or less, and even more preferably 4 or less. The molecular weight distribution is preferably 1.5 or more, and more preferably 1.2 or more. In addition, Mw, Mn and Mw / Mn are values using polystyrene conversion values that can be obtained by gel permeation chromatography (GPC). If the molecular weight distribution is within the applicable range and the acid value range is above, the alkali desorption and drying properties, substrate adhesion, retort resistance, etc. are satisfied.

In order to keep the molecular weight distribution (Mw / Mn) in the above range, in polyurethane resin synthesis, the ratio of urethane synthetic raw material / organic solvent (solid content ratio), the dropping rate of reactive raw material such as polyisocyanate, and further, during the reaction The molecular weight distribution (Mw / Mn) can be kept within the range by appropriately setting the stirring speed and the uniformity of the reaction solution. When the chain extension reaction is further carried out, the molecular weight distribution is determined by setting the balance between the dropping / contact speed and the stirring speed of the polyamine and the urethane prepolymer, which will be described later, and the temperature range control at the time of chain extension to a constant width. It is effective to make it a range.
Further, it is effective to set the molecular weight distribution within a predetermined range by setting the charging ratio of the reaction raw materials to an appropriate ratio. The charging ratio includes, for example, the NCO / OH ratio, which is the ratio of the hydroxyl groups of polyol and hydroxyic acid, and the isocyanate group of polyisocyanate, and is the ratio of the amino group of polyamine to the isocyanate group of urethane prepolymer. , Amino group / NCO ratio and the like. Further, in order to control the molecular weight distribution, it is preferable to use a polymerization terminator (also referred to as a reaction terminator) for the purpose of preventing an excessive polymerization reaction. Preferable examples of the polymerization terminator include monoalcohols and monoamines.

The weight average molecular weight (Mw) of the polyurethane resin is preferably 1000 to 100,000. It is still more preferably 1500 to 70000, and even more preferably 1500 to 50000. This is because the blocking resistance, work efficiency in the printing process of the organic solvent-based printing ink, printability, and the like are improved. Further, the molecular weight distribution (Mw / Mn) improves the desorption property with an alkaline aqueous solution.

The polyurethane resin may have an amine value, and when it has an amine value, it is preferably 0.1 to 20 mgKOH / g, and more preferably 1 to 10 mgKOH / g. This is because the adhesion to the base material is good.

The polyurethane resin is not limited by the production method thereof, but it is preferable to use, for example, a polyurethane resin obtained by reacting polyisocyanate, polyol and hydroxy acid.
Further, it is still preferable to use a polyurethane resin obtained by further reacting a urethane prepolymer obtained by reacting a polyisocyanate, a polyol and a hydroxy acid with a polyamine (referred to as a chain extension reaction). In any of the above cases, the polyurethane resin can be imparted with an acid value by using a hydroxy acid.

(Polyisocyanate)
As the polyisocyanate used in the polyurethane resin used for the organic solvent-based printing ink, diisocyanate and / or triisocyanate are preferable, and aromatic, aliphatic or alicyclic diisocyanate can be preferably used.
For example, 1,5-naphthylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-dibenzylisocyanate, dimethyldiphenylmethane diisocyanate, tetramethyldiphenylmethane diisocyanate, 1,3- Phenylene diisocyanate, 1,4-phenylenediocyanate, m-xylylene diisocyanate, p-xylylene diisocyanate, o-xylylene diisocyanate and 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate and other aromatic diisocyanates,
Tetramethylene diisocyanate, hexamethylene diisocyanate, isopropylene diisocyanate, methylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate and other aliphatic diisocyanates,
Cyclohexane-1,4-diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, lysine diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, methylcyclohexanediisocyanate, m-tetramethyl Preferable examples thereof include xylylene diisocyanate, diisocyanate obtained by converting the carboxyl group of dimer acid into an isocyanate group, and other alicyclic diisocyanates. These can be used alone or in combination of two or more.

Of the above, from the viewpoint of reactivity, etc., from isophorone diisocyanate, 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, tolylene diisocyanate, hexamethylene diisocyanate, dicyclohexylmethane-4,4'-diisocyanate. At least one use of choice is preferred. It is also preferable that these diisocyanates are trimers and triisocyanates having an isocyanurate structure.

(Polyprethane)
The polyurethane resin has a constituent unit derived from a polyol, and the polyol is not particularly limited and is not limited to the following, but a polyether polyol, a polyester polyol, a polycarbonate polyol, and the like are preferably used. Polypoly is a general term for compounds having at least two hydroxyl groups in one molecule, but does not contain hydroxy acids, which will be described later.
Further, as the polyol, other dimer diols, hydrogenated dimer diols, castor oil-modified polyols and the like may be used. The polyurethane resin preferably has at least one constituent unit selected from a polyether constituent unit, a polyester constituent unit and a polycarbonate constituent unit, and more preferably contains a constituent unit derived from a polyester polyol.
The total mass of the polyurethane resin preferably contains 10 to 75% by mass of a constituent unit derived from polyol, and more preferably 15 to 70% by mass. It is more preferable to contain 20 to 65% by mass.

As the usage form of the polyol, it is preferable that the constituent unit derived from the polyester polyol is contained in an amount of 5% by mass or more in the total mass of the constituent units derived from the polyol. It is still more preferable to contain 30% by mass or more, and further preferably 40% by mass or more. In addition to the action of incorporating a hydroxy acid, which will be described later, into a polyurethane resin, it is possible to impart desorption by an alkali, that is, the ability to desorb a desorbing layer and a pattern layer from a plastic base material with an alkaline aqueous solution, and a polyester polyol. In order to further improve the desorption property by alkaline hydrolysis of the ester bond site of the above, the content is preferably 50% by mass or more, and more preferably 70% by mass or more. It is more preferable to contain 80% by mass or more.

The number average molecular weight of the polyol is preferably 500 to 10000. Here, the number average molecular weight used for the polyol is calculated from the hydroxyl value. The hydroxyl value means a value measured by JISK0070. When the number average molecular weight of the polyol is 10,000 or less, the blocking resistance to the plastic film is excellent. Further, when the number average molecular weight of the polyol is 500 or more, the flexibility of the polyurethane resin film is excellent and the adhesion to the plastic film is excellent. For the above reasons, the number average molecular weight is more preferably 1000 to 5000.

(Polyester polyol)
Preferable examples of the polyester polyol include a polyester polyol composed of a condensate of a dibasic acid and a diol, and a polyester polyol composed of a polylactone polyol which is a ring-opening polymer of a cyclic ester compound. It is preferably a polyester diol. Examples of the dibasic acid 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 are preferable, and adipic acid, succinic acid and the like are preferable.
Examples of the diol include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 1,6-hexanediol, and 1,8-octanediol. , 1,9-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, 1,2-Alkanediol, 1,3-Alkanediol, 1-monoglyceride, 2-monoglyceride, 1-monoglycerin ether, 2-monoglycerin ether, dimerdiol , Hydrophobic dimerdiol and the like are preferable. The polyester polyol can be used alone or in combination of two or more. Further, as a raw material for the polyester polyol, a polyol having 3 or more hydroxyl groups and a polyvalent carboxylic acid having 3 or more carboxyl groups can be used in combination. Preferable examples of the cyclic ester compound include α-acetolactone, β-propiolactone, γ-butyrolactone, δ-valerolactone, and ε-caprolactone.

(Ester bond concentration)
In the second embodiment of the present invention, the polyol is required to contain 50% by mass of a polyester polyol having an ester bond concentration of 4 to 11 mmol / g in the total mass of the polyol. The ester bond concentration referred to here is a numerical value calculated by the following formula (1).

Formula (1) Ester bond concentration (mmol / g) = total number of moles of ester bonds contained in the polyester polyol (mmol) / total solid content mass (g) of the polyester polyol

In order to improve the desorption of the ink layer, the ester bond concentration of the polyester polyol is preferably 7 to 11 mmol / g, more preferably 8 to 11 mmol / g, and 9 to 11 mmol / g. It is still preferable to have.

In the second embodiment of the present invention, for example, it is preferable that the polyester polyol has a structural unit represented by the following general formula (1).

General formula (1)

(In the formula, R ¹ and R ² are substituted or unsubstituted alkylene groups having 1 to 10 carbon atoms, and R ¹ and R ² may be the same or different, respectively, and n is a natural number.)

The polyester polyol is obtained by polycondensation of dibasic acid and diol. In that case (the number of moles of hydroxyl groups of the diol / the number of moles of the carboxyl groups of the dibasic acid)> 1
In this case, the ester bond concentration is represented by the following formula (2).

Equation (2)
Ester bond concentration (mmol / g) = total number of moles of carboxyl group (mmol) / total solid content of polyester polyol (g)

Here, the total number of moles of carboxyl groups means the total number of moles of carboxyl groups of the dibasic acid used in producing a polyester polyol.

In the first embodiment or the second embodiment, the alkylene group (R ¹ ) contained in the dibasic acid for producing the polyester polyol is a substituted or unsubstituted alkylene group. It is preferable that the number of carbon atoms for linearly connecting the carboxyl groups of the dibasic acid is 1 to 6. It is still preferable that the number of carbon atoms is 1 to 3. Here, the alkylene group (R ¹ ) contained in the dibasic acid is the same as R ¹ in the above general formula (1). Examples of the dibasic acid having R ¹ include adipic acid, succinic acid, and sebacic acid.
In the above embodiment 1 or embodiment 2, for the manufacture of a polyester polyol, an alkylene group (R ²⁾ having a diol, a substituted or unsubstituted alkylene group, linking the hydroxyl groups possessed by diol linear The number of carbon atoms is preferably 1 to 6. It is still preferable that the number of carbon atoms is 1 to 3. The alkylene group (R ² ) contained in the diol is the same as R ² in the general formula (1). Diols having R ² is, for example, 1,2-propanediol (propylene glycol), 1,3-butanediol, 2-methyl-1,3-propanediol, 3-methyl-1,5-pentanediol Applicable.

Already described as "connecting the carboxyl groups to each other in a linear carbon atoms / number of carbon atoms connecting the hydroxy groups in a straight chain" means that the R ^1, the number of carbon atoms is not included with the branched carbon or substituent in R ² For example, 3-methyl-1,5-pentanediol has 6 carbon atoms, but "the number of carbon atoms connecting hydroxyl groups in a straight chain" is 5. Similarly, 2-butyl-2-ethyl-1,3-propanediol has 9 carbon atoms, but "the number of carbon atoms connecting the hydroxyl groups in a straight chain" is 3. The same is defined for dibasic acids.
In addition, "the number of carbons connected by a straight line" may be referred to as "the number of linear carbons", but it is synonymous.

The polyester polyol is a condensate of a dibasic acid having a carboxyl group at both ends of the alkylene group (R ¹ ) and a diol having hydroxyl groups at both ends of the alkylene group (R ² ), and is a carboxyl of the dibasic acid. Either the number of carbon atoms that linearly connects the groups or the number of carbon atoms that linearly connects the hydroxyl groups of the diol is preferably 1 to 6, and the number of carbon atoms is 1 to 3. Is still preferable.

It is also preferable that the polyester diol contains a constituent unit derived from polyester, which is a condensate of a diol having a branched structure and a dibasic acid. This is also because the adhesion to the plastic base material and the retort resistance can be improved. The diol having a branched structure is preferably a diol having a structure in which at least one hydrogen atom of the alkylene glycol is substituted with an alkyl group, and the diol having a branched structure is, for example, 1,2-propane. Diol (propylene glycol), 1,3-butanediol, 2-methyl-1,3-propanediol, neopentyl glycol, 1,4-pentanediol, 3-methyl-1,5-pentanediol, 2,5- Hexanediol, 2-methyl-1,4-pentanediol, 2,4-diethyl-1,5-pentanediol, 2-butyl-2-ethyl-1,3-propanediol, 2-methyl-1,8- Preferable examples include octanediol, 2,2,4-trimethyl-1,3-pentanediol, and 2,2,4-trimethyl-1,6-hexanediol. Of these, at least one selected from 1,2-propanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, and 2-butyl-2-ethyl-1,3-propanediol is preferable, and 1 , 2-Propylenediol (propylene glycol) and / or polyester polyols containing 3-methyl-1,5-pentanediol are still preferred.

(Hydroxy acid)
The hydroxy acid refers to a compound having both a hydroxyl group, which is an active hydrogen group, and an acidic functional group in one molecule. The hydroxy acid is not particularly limited, but dimethylol alkanoic acid such as 2,2-dimethylol propionic acid, 2,2-dimethylol butanoic acid, and 2,2-dimethylol valeric acid is preferable. These can be used alone or in combination of two or more, and may be appropriately adjusted so that the acid value of the polyurethane resin is 15 to 70 mgKOH / g. The acid value is a value measured by JISK0070.

In the above, the acidic functional group indicates a functional group that can be neutralized with potassium hydroxide when measuring the acid value, and specific examples thereof include a carboxyl group and a sulfonic acid group, which are carboxyl groups. Is preferable. In the process of synthesizing the polyurethane resin, the acidic group has a high probability of not reacting with the isocyanate group, so that the acid value can be maintained in the polyurethane resin.

Further, as described above, the polyurethane resin is a polyurethane resin obtained by further reacting a urethane prepolymer having an isocyanate group at the terminal formed by reacting polyisocyanate, polyol and hydroxyic acid with polyamine (referred to as a chain extension reaction). Is preferable. In this case, a urea bond is formed in addition to the urethane bond. It is preferable to use the same polyisocyanate, polyol and hydroxy acid as described above.

(Polyamine)
The polyamine preferably has a diamine, and is not limited to the following, but uses ethylenediamine, propylenediamine, hexamethylenediamine, isophoronediamine, dicyclohexylmethane-4,4'-diamine, and a carboxyl group of dimer acid as an amino group. Diamines such as converted diamine diamines are preferred. These can be used alone or in combination of two or more.
Particularly preferred are 2-hydroxyethylethylenediamine, 2-hydroxyethylpropylenediamine, di-2-hydroxyethylethylenediamine, di-2-hydroxyethylpropylenediamine, 2-hydroxypropylethylenediamine, di-2-hydroxypropylethylenediamine and the like. It is a diamine having a hydroxyl group. By using these, a certain amount of hydroxyl groups remains unreacted in the polyurethane resin manufacturing process, and the polyurethane resin can contain the hydroxyl value.
Amino acids can also be used for chain extension. The amino acid refers to a compound having both an amino group and an acidic functional group in one molecule, and preferred examples thereof include glutamine, asparagine, lysine, diaminopropionic acid, ornithine, diaminobenzoic acid, and diaminobenzenesulfonic acid. In the process of synthesizing the polyurethane resin, the acidic group has a high probability of not reacting with the isocyanate group, so that the acid value can be maintained in the polyurethane resin.

(Polymerization inhibitor)
A polymerization inhibitor can also be used in combination with the above polyamine. Examples of such a polymerization terminator include dialkylamine compounds such as di-n-dibutylamine.
Monoethanolamine, diethanolamine, butanolamine, 2-amino-2-methyl-1-propanol, tri (hydroxymethyl) aminomethane, 2-amino-2-ethyl-1,3-propanediol, N-di-2- Amine compounds having hydroxyl groups such as hydroxyethylethylenediamine, N-di-2-hydroxyethylpropylenediamine, N-di-2-hydroxypropylethylenediamine, etc.
Further, monoamine type amino acid compounds such as glycine, alanine, glutamic acid, taurine, aspartic acid, aminobutyric acid, valine, aminocaproic acid, aminobenzoic acid, aminoisophthalic acid and sulfamic acid can be mentioned. In order to make the polyurethane resin contain a hydroxyl value, it is preferable to use an amine compound having a hydroxyl group.

(Synthesis of polyurethane resin)
The method for synthesizing the polyurethane resin according to the embodiment of the present invention will be described. Polyurethane resin is formed by reacting polyisocyanate, polyol and hydroxy acid (referred to as urethanization step). The reaction ratio (NCO / OH) of the polyisocyanate to the polyol and the hydroxy acid is preferably 1.05 to 3.0, more preferably 1.1 to 2.8. The urethanization reaction step is preferably carried out at a temperature of 70 to 90 ° C. for 2 to 8 hours using an organic solvent inert to the isocyanate group, if necessary, and further using a catalyst if necessary. At this time, the polyisocyanate can be added dropwise at an appropriate rate while the polyol and the organic solvent are mixed and stirred. The stirring speed during the reaction is preferably that the reaction solutions are uniformly mixed, and that the stirring speed is appropriate and uniform rather than excessively slow stirring or excessively fast stirring.

When the polyurethane resin is further subjected to a chain extension reaction with polyamine as a urethane prepolymer having an isocyanate group at the terminal obtained by the urethanization reaction step (referred to as a urea conversion reaction step), the solid content of the urethane prepolymer or polyamine is used. It is preferable to set it appropriately, and it is preferable to control the dropping rate relatively slowly and at a constant rate. Since the viscosity of the urea conversion reaction step changes significantly as the reaction progresses, it is preferable to prepare a uniform reaction solution, and it is preferable to set the stirring speed to be high. The amino group / NCO, which is the ratio of the isocyanate group of the urethane prepolymer to the amino group of the polyamine, is preferably 0.7 to 1.3, and the reaction is carried out in a temperature range of 20 to 60 ° C. for 1 to 8 hours. It is preferable to carry out over.

(Urethane bond concentration)
Urethane bond concentration refers to the value expressed by the following equation.
In the above case, when (NCO mole number / OH mole number)> 1, it is represented by the following formula (3).

Equation (3)
Urethane bond concentration (mmol / g) = total number of moles of hydroxyl groups (mmol) / total mass of solids (g)

Here, the total number of moles of hydroxyl groups refers to the total number of moles of hydroxyl groups of polyols, hydroxy acids, etc. used in the reaction for forming urethane. The total solid content refers to the total mass of the non-volatile components of the polyurethane resin.
In the above case, when (NCO mole number / OH mole number) <1, it is represented by the following formula (4).

Equation (4)
Urethane bond concentration (mmol / g) = total number of moles of isocyanate groups (mmol) / total solid mass (g)

Here, the total number of moles of isocyanate groups refers to the total number of moles of isocyanate groups contained in the polyisocyanate used in the reaction for forming urethane.

(Urea binding concentration)
The urea bond concentration is a value expressed by the following equation.
When a prepolymer having a terminal isocyanate group is synthesized under the above condition (number of moles of NCO / number of moles of OH)> 1, the chain is extended with a polyamine, and the polyurethane resin has an amino group at the end, it is represented by the following formula (5). Will be done.

Equation (5)
Urea bond concentration (mmol / g) = [total number of moles of isocyanate groups (mmol) -total number of moles of hydroxyl groups (mmol)] / total mass of solids (g)

When a prepolymer having a terminal isocyanate group is synthesized under the above condition (number of moles of NCO / number of moles of OH)> 1, the chain is extended with a polyamine, and the polyurethane resin has an isocyanate group at the end, it is represented by the following formula (6). Will be done.

Equation (6)
Urea bond concentration (mmol / g) = (total number of moles of amino groups (mmol)) / total mass of solids (g)

Here, the total number of moles of amino groups is the total number of moles of primary and / or secondary amino groups of a polyamine used for reacting with a prepolymer having a terminal isocyanate group to form a urea bond. Say.

The urethane bond concentration of the polyurethane resin is preferably 1 to 3 mmol / g, and more preferably 1.5 to 2 mmol / g. The urea bond concentration is preferably 0 to 3 mmol / g, and more preferably 0.2 to 1 mmol / g. Further, the total of the urethane bond concentration and the urea bond concentration is preferably 1 to 6 mmol / g, and more preferably 1.7 to 3 mmol / g. This is because desorption and substrate adhesion are improved by setting the urethane bond concentration and / or the urea bond concentration in the corresponding range.

(Combination resin)
In the embodiment of the present invention, the binder resin is also suitable when other resins are used in combination with the above-mentioned polyurethane resin, and examples thereof are not limited to the following, but are not limited to the following, but are limited to cellulose resins, polyamide resins, and vinyl chlorides. Vinyl chloride resin such as vinyl acetate copolymer resin, vinyl chloride-acrylic copolymer resin, rosin resin, ethylene-vinyl acetate copolymer resin, vinyl acetate resin, acrylic resin, styrene resin, dammar resin, styrene-malein Acid copolymer resin, styrene-acrylic copolymer resin, polyester resin, alkyd resin, terpen resin, phenol-modified terpen resin, ketone resin, cyclized rubber, rubber chloride, butyral, polyacetal resin, petroleum resin, and their modified resins, etc. Can be mentioned. These resins can be used alone or in admixture of two or more. Above all, it is preferable to use at least one selected from the group consisting of vinyl chloride resin, acrylic resin, cellulosic resin, styrene-maleic acid copolymer resin, and rosin resin. It is still preferable that it is at least one selected from the group consisting of vinyl chloride resin, styrene-maleic anhydride copolymer resin, and rosin resin. The ratio of the polyurethane resin to the combined resin is more preferably 95: 5 to 50:50 for the former: the latter. This is because the detached pattern layer and the like can be easily collected.

<Organic solvent>
The organic solvent-based printing ink of the embodiment of the present invention contains an organic solvent. The organic solvent is not limited to the following, but examples of the organic solvent used include aromatic organic solvents such as toluene and xylene, ketone organic solvents such as methyl ethyl ketone and methyl isobutyl ketone, ethyl acetate and n-propyl acetate. Known alcohol-based organic solvents such as isopropyl acetate, isobutyl acetate, ester-based organic solvents, methanol, ethanol, n-propanol, isopropanol and n-butanol, glycol ether-based solvents such as ethylene glycol monopropyl ether and propylene glycol monomethyl ether. An organic solvent can be used, and it is preferable to use a mixture. Among them, an organic solvent (non-toluene-based organic solvent) that does not contain aromatic organic solvents such as toluene and xylene is preferable because the stability of the gravure ink over time becomes good when a hydrocarbon-based wax is contained. Is more preferable, and it is more preferable to contain an ester-based organic solvent and an alcohol-based organic solvent. When an ester-based organic solvent and an alcohol-based organic solvent are contained, a mixed organic solvent containing an ester-based organic solvent: alcohol-based organic solvent in a mass ratio of 90: 10 to 40:60 is more preferable. Further, the glycol ether-based organic solvent may be contained in an amount of 5% by mass or less in 100% by mass of the ink.

<Additives>
The organic solvent-based printing ink can appropriately contain conventionally known additives, and in the production of gravure ink, additives such as pigment derivatives, dispersants, wetting agents, adhesive aids, and leveling agents are required. , Antifoaming agent, antistatic agent, viscosity modifier, metal chelate, trapping agent, blocking inhibitor, wax component other than the above, isocyanate-based curing agent, silane coupling agent and the like can be used.

<Organic solvent-based printing ink>
The organic solvent-based printing ink according to the embodiment of the present invention includes a form of a clear ink or a color ink. However, the form further containing an organic solvent, other inks, etc. is not excluded as long as the gist of the present invention is not changed.

<Clear ink>
The clear ink means a form in which the ink or the printing layer is substantially cloudy or colorless / transparent, and does not exclude even a slight coloring caused by a binder resin, an extender pigment, an additive, or the like. The solid content of the clear ink in the total mass of the ink is preferably 5 to 50% by mass, and more preferably 10 to 40% by mass. Further, the binder resin is preferably contained in the total mass of the ink in an amount of 0.5 to 50% by mass, and more preferably 5 to 30% by mass. Within the above range, the viscosity of the clear ink becomes appropriate, and when the ink is applied to the plastic film using an arbitrary printing method, the printability such as halftone dot reproducibility becomes good. The "solid content" means the total mass% of the non-volatile components.

(Constitution pigment)
The clear ink preferably contains an extender pigment. As the extender pigment, silica, barium sulfate, kaolin, clay, calcium carbonate, magnesium carbonate, metal oxides such as zinc oxide and zirconium oxide are preferable. These are used to improve fluidity, coating strength and optical properties. Of these, silica is preferably used, and hydrophilicity is preferable. The extender pigment preferably has an average particle size of 0.5 to 10 μm, and more preferably 1 to 8 μm. The extender pigment is preferably contained in an amount of 0.5 to 10% by mass, more preferably 1 to 5% by mass, in the total mass of the ink. This is because the wettability of the pattern ink becomes good when the pattern ink is overprinted.

<Color ink>
The color ink refers to an organic solvent-based printing ink containing a colorant, and does not include the above-mentioned clear ink. The colorant component is preferably a color dye and / or a color pigment. The solid content of the color ink in the total mass of the ink is preferably 5 to 50% by mass, and more preferably 10 to 40% by mass. The colorant is preferably contained in an amount sufficient to secure the density and coloring power of the ink, that is, 1 to 50% by mass, and more preferably 3 to 15% by mass in the total mass of the ink. The binder resin preferably contains 0.5 to 50% by mass of solid content in the total mass of the ink, and more preferably 5 to 30% by mass. Within the above range, the viscosity of the color ink becomes appropriate, and when the ink is applied to the plastic film by using an arbitrary printing method, the printability such as halftone dot reproducibility becomes good. As the color ink, an extender pigment may be used as an auxiliary, and the extender pigment is preferably the same as in the case of the above clear ink.

(Coloring pigment)
The colorant is preferably a pigment, and the mass ratio of the binder resin to the color pigment (binder resin / pigment) is preferably 99/1 to 10/90. Further, it is more preferably 80/20 to 20/80. The coloring pigment is preferably an organic pigment or an inorganic pigment, and the inorganic pigment preferably contains titanium oxide, and the organic pigment preferably consists of an organic compound or an organic metal complex.

Organic pigments among the coloring pigments are not limited to the following examples, but are soluble azo type, insoluble azo type, azo type, phthalocyanine type, halogenated phthalocyanine type, anthraquinone type, anthraslon type, dianthraquinone type, and anthra. Pyrimidine, perylene, perinone, quinacridone, thioindigo, dioxazine, isoindolinone, quinophthalone, azomethinazo, flavanthron, diketopyrrolopyrrole, isoindoline, indanslon, carbon black Pigments such as system can be mentioned. Also, for example, Carmin 6B, Lake Red C, Permanent Red 2B, Disazo Yellow, Pyrazolone Orange, Carmin FB, Chromophtal Yellow, Chromophtal Red, Phthalocyanine Blue, Phthalocyanine Green, Dioxazine Violet, Quinacridone Magenta, Quinacridone Red, Indance. Examples thereof include lonblue, pyrimidine yellow, thioindigo bordeaux, thioindigo magenta, perylene red, perinone orange, isoindolinone yellow, aniline black, diketopyrrolopyrrole red, and daylight fluorescent pigment.

Among the coloring pigments, examples of the inorganic pigments include white inorganic pigments such as titanium oxide, zinc oxide, zinc sulfide, and chromium oxide. Among the inorganic pigments, the use of titanium oxide is particularly preferable. Titanium oxide has a white color and is preferable from the viewpoints of coloring power, hiding power, chemical resistance and weather resistance, and from the viewpoint of printing performance, the titanium oxide is preferably treated with silica and / or alumina.

Among the coloring pigments, inorganic pigments other than white include, for example, aluminum particles, mica (mica), bronze powder, chrome vermilion, chrome yellow, cadmium yellow, cadmium red, ultramarine, dark blue, red iron oxide, yellow iron oxide, and iron black. , Titanium oxide, zinc oxide and the like, and aluminum is in the form of powder or paste, but it is preferable to use it in the form of paste from the viewpoint of handleability and safety, and it may be either a chrome yellow type or a non-leaving type.

<Production of Organic Solvent-based Printing Ink> The organic solvent-based printing ink can be produced by dissolving and / or dispersing a binder resin, an extender pigment, a coloring pigment, or the like in an organic solvent.
For example, a pigment, a polyurethane resin, a binder resin such as vinyl chloride-vinyl acetate copolymer resin, silica particles, and an organic solvent as needed are dispersed, and a polyurethane resin and an organic solvent, if necessary, are dispersed in the pigment dispersion. An organic solvent-based printing ink can be produced by blending other resins and additives. The viscosity and color of the organic solvent-based printing ink can be adjusted by appropriately adjusting the size of the crushed media of the disperser, the filling rate of the crushed media, the dispersion treatment time, the discharge rate of the pigment dispersion, the viscosity of the pigment dispersion, and the like. , Can be adjusted. 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 used. It is preferably produced using a sand mill.

The viscosity of the organic solvent-based printing ink is preferably in the range of 20 to 500 mPa · s, and more preferably 30 to 300 mPa · s. This is because appropriate printability can be obtained in the printing process. The viscosity of the printing ink can be adjusted by adjusting the amount of the polyurethane resin and other binder resins, the amount of the organic solvent, and the dispersion conditions of the pigment.

(Pattern ink)
The picture ink refers to a printing ink that does not have the above-mentioned desorption function, and preferred examples thereof include screen ink, gravure ink, flexo ink, inkjet ink, offset ink, and other printing inks. For example, Japanese Patent Application Laid-Open No. 2005-298618. , JP-A-2006-299136, JP-A-2009-249388, JP-A-2013-127038, JP-A-2017-19991, JP-A-2006-131844, JP-A-2013-40248, The printing inks described in JP-A-2007-231148, JP-A-2006-257302 and the like can be preferably used. However, it is not limited to these. Among them, the use of gravure ink, flexo ink, and inkjet ink is preferable, and the use of gravure ink and / or flexo ink is still preferable.

<Printing of organic solvent-based printing ink>
As a printing method of the organic solvent-based printing ink, a printing method such as screen printing, offset printing, flexo printing, dry offset printing, gravure printing, and inkjet printing can be preferably used. Of these, gravure printing or flexographic printing is still preferable.

<Gravure printing>
(Gravure plate) The gravure plate is a metal cylindrical one, and recesses are made for each color by engraving, corrosion, or laser. There are no restrictions on the use of engraving and laser, and it can be set arbitrarily according to the pattern. As the number of lines, those of 100 to 300 lines are appropriately used, and the larger the number of lines, the finer the printing is possible. The thickness of the print layer is preferably 0.1 μm to 100 μm.
(Printer)
In a gravure printing machine, one printing unit includes the above gravure plate and a doctor blade. There are many printing units, and printing units corresponding to organic solvent-based printing inks and pattern inks can be set, and each unit has an oven drying unit. Printing is performed by rotary printing, which is a take-up printing method. The type of plate and the type of doctor blade are appropriately selected, and the one according to the specifications can be selected.

<Flexographic printing>
(Flexographic plate) Examples of the plate used for flexographic printing include a photosensitive resin plate that utilizes ultraviolet curing by a UV light source and an elastomer material plate that uses a direct laser engraving method. Regardless of the method of forming the image portion of the flexographic plate, a plate having a screening line number of 75 lpi or more is used. Any sleeve or cushion tape can be used to attach the plate.
(Printer)
Flexographic printing machines include CI type multicolor flexographic printing machines, unit type multicolor flexographic printing machines, etc., and the ink supply method can be a chamber method or a two-roll method, and an appropriate printing machine can be used. it can.

<Printed matter and laminate>
The form of the printed matter and the laminate in the embodiment of the present invention is not limited, but the following aspects are preferably mentioned.
-Base material 1 / desorption layer (clear) / pattern layer-base material 1 / desorption layer (color) / pattern layer-base material 1 / desorption layer (clear) / adhesive layer / base material 2
-Base material 1 / Desorption layer (color) / Adhesive layer / Base material 2
-Base material 1 / Desorption layer (clear) / Pattern layer / Adhesive layer / Base material 2
-Base material 1 / Desorption layer (color) / Pattern layer / Adhesive layer / Base material 2
-Picture layer / Desorption layer (clear) / Base material 1 / Adhesive layer / Base material 2
-Picture layer / Desorption layer (color) / Base material 1 / Adhesive layer / Base material 2
-Base material 1 / Desorption layer (clear) / Pattern layer / Desorption layer (Clear) / Adhesive layer / Base material 2
-Base material 1 / Desorption layer (color) / Pattern layer / Desorption layer (color) / Adhesive layer / Base material 2
In the above, "clear" represents clear ink, and "color" represents color ink.

<Base material 1>
Examples of the base material to which the organic solvent-based printing ink can be applied include polyethylene and polypropylene and other polyolefin base materials, polycarbonate base materials, polyethylene terephthalate, polylactic acid and other polyester base materials, polystyrene base materials, and polystyrene-based base materials such as AS resin or ABS resin. Resin, polyamide base material, polyvinyl chloride base material, various base materials of polyvinylidene chloride, cellophane base material, paper base material, aluminum foil base material, etc., or film-like or sheet-like materials made of these composite materials is there. Of these, polyester base materials and polyamide base materials having a high glass transition temperature are preferably used.

The surface of the base material may be coated with a metal oxide or the like by vapor deposition and / or a coating treatment such as polyvinyl alcohol. For example, GL- manufactured by Toppan Printing Co., Ltd., in which aluminum oxide is vapor-deposited on the surface of the base material 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 protective agents, 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>
The base material 2 may be the same as the base material 1, and may be the same or different. It is preferably a thermoplastic base material (sometimes referred to as a sealant), and a non-stretched polyethylene base material, a non-stretched polypropylene base material, a non-stretched polyester base material, or the like is preferable.

<Adhesive layer>
A laminating process using an adhesive is required to bond the base material 1 and the base material 2. Typical examples of the laminating process include an extrusion laminating method, a dry laminating method, and a non-solvent laminating method. The laminating process is a method in which an adhesive layer is provided on any surface of a printed matter by coating, drying, or the like, and further pressed against the base material 2 for laminating. The adhesive layer is not limited to the following, and preferably includes an anchoring agent layer, a molten resin layer, a urethane-based adhesive layer, an acrylic-based adhesive layer, and the like, and can be obtained by a melt extrusion method, a coating method, or the like. For example, a urethane-based adhesive is preferably a two-component adhesive composed of a mixture of a polyol and an isocyanate curing agent, and examples of the polyol are polyester-based and polyether-based. Specific examples thereof include TM-250HV / CAT-RT86L-60, TM-550 / CAT-RT37, TM-314 / CAT-14B manufactured by Toyo Morton Co., Ltd.

(Elimination process)
The method for producing a recycled base material according to the embodiment of the present invention includes a step of immersing a printed matter or a laminated laminate in a basic aqueous solution (alkaline aqueous solution). As a condition for removing the desorbed layer and the like (desorbed layer, pattern layer, and other layers) in the embodiment of the present invention, the concentration of the alkaline aqueous solution is preferably 0.5 to 15% by mass, preferably 1 to 5% by mass. % Is still preferable. When the concentration is within the above range, the alkaline aqueous solution can maintain sufficient alkalinity for desorption.
In the desorption, the alkaline aqueous solution permeates from the surface of the printed layer in the printed matter and from the end portion in the laminated laminate and comes into contact with the desorbed layer to dissolve the desorbed layer, so that the desorbed layer can be desorbed. More preferably, the printed matter or the laminated body has a desorption layer on the cross section, and the pattern ink layer, the base material, or the like can be desorbed in a shorter time.

The immersion time in the basic aqueous solution is 1 minute to 12 hours, more preferably 1 minute to 6 hours. After that, it can be washed with water and dried to obtain a recycled base material. The removal rate of the desorption layer from the base materials such as the base material 1 and the base material 2 and the accompanying pattern layer / adhesive layer, etc. is such that the desorption ability of the desorption layer is uniform in the plane direction (partial curing). Of the desorbed layer of the base material, it is preferably 80% by mass or more, more preferably 90% by mass or more, and further preferably 95% by mass or more. At the time of immersion, it is preferable to perform desorption while stirring. For example, when stirring with a stirring device rotary blade, the speed is preferably 80 to 250 rpm, and more preferably 80 to 200 rpm.

The temperature of the basic aqueous solution at the time of immersion is preferably 25 to 110 ° C., more preferably 30 to 90 ° C., and even more preferably 30 to 80 ° C. The immersion time is 1 minute to 24 hours, more preferably 1 minute to 12 hours. After that, when the plastic base material (recycled base material) is washed and dried with water, the removal rate of the desorbed layer and the associated pattern ink layer, adhesive layer, etc. is preferably 80% by mass or more, more preferably 90% by mass or more. , More preferably 95% by mass or more. In the case of the front printing form, the concentration of the alkaline aqueous solution is preferably 0.5 to 15% by mass, the immersion temperature is preferably 30 to 80 ° C., and the immersion time is 1 to 12 hours. preferable. In the back printing (laminated laminate), the concentration of the alkaline aqueous solution is preferably 1 to 15% by mass, the immersion temperature is preferably 30 to 80 ° C., and the immersion time is preferably 1 to 12 hours.

The amount of the alkaline aqueous solution used is preferably 1 to 1,000,000 times the mass of the printed matter or laminate. Further, in order to improve efficiency, circulation type washing, crushing and stirring of printed matter or laminate may be performed.

According to the embodiment of the present invention, a recycled plastic base material (recycled base material) is obtained by removing the desorbed layer from a printed matter or a laminate in an alkaline aqueous solution, washing the base material with water, and drying the base material. Can be done. Further, the recycled plastic base material can be recycled into pellets by an extruder or the like and reused.

<Example of Embodiment>
Examples of preferred embodiments of the present invention are given below. Embodiments of the present invention are not limited to the following examples.

[1] The pattern layer and / or the base material 2 is peeled off from the printed matter or laminate having the base material 1, the desorption layer, and the pattern layer and / or the base material 2 in this order, and the base material 1 is recycled. An organic solvent-based printing ink used to form a desorption layer for this purpose.
The organic solvent-based printing ink is an organic solvent-based printing ink containing a polyurethane resin having an acid value of 15 to 70 mgKOH / g and a hydroxyl value of 1 to 35 mgKOH / g as a binder resin.

[2] The organic solvent-based printing ink, wherein the polyurethane resin contains a constituent unit derived from a polyol, and the polyol contains at least one selected from a polyester polyol, a polyether polyol, and a polycarbonate polyol.

[3] The pattern layer and / or the base material 2 is peeled off from the printed matter or laminate having the base material 1, the desorption layer, and the pattern layer and / or the base material 2 in this order, and the base material 1 is recycled. An organic solvent-based printing ink used to form a desorption layer for this purpose.
The organic solvent-based printing ink contains a polyurethane resin having an acid value of 15 to 70 mgKOH / g as a binder resin, and the polyurethane resin contains a constituent unit derived from a polyol.
The polyol is an organic solvent-based printing ink containing 50% by mass or more of a polyester polyol having an ester bond concentration of 4 to 11 mmol / g.

[4] The organic solvent-based printing ink is the above-mentioned organic solvent-based printing ink, which is an organic solvent-based clear ink.

[5] The organic solvent-based printing ink having a polyurethane resin having a molecular weight distribution (Mw / Mn) of 6 or less.

[6] The polyester polyol is a condensate of a dibasic acid having a carboxyl group at both ends of the alkylene group (R ¹ ) and a diol having hydroxyl groups at both ends of the alkylene group (R ² ).
Either one of the carbon number that linearly connects the carboxyl groups of the dibasic acid and the carbon number that linearly connects the hydroxyl groups of the diol has 1 to 6 carbon atoms.
The organic solvent-based printing ink in which the alkylene groups (R ¹ ) and (R ² ) are substituted or unsubstituted alkylene groups.

[7] The organic having 1 to 6 carbon atoms, both of the carbon number of linearly connecting the carboxyl groups of the dibasic acid and the carbon number of linearly connecting the hydroxyl groups of the diol. Solvent-based printing ink.

[8] The organic solvent-based printing ink further contains at least one resin selected from the group consisting of cellulose-based resin, vinyl chloride-based resin, rosin-based resin, acrylic resin, and styrene-maleic acid copolymer resin. Organic solvent-based printing ink.

[9] The organic solvent-based printing ink is the above-mentioned organic solvent-based printing ink further containing an extender pigment.

[10] A printed matter having a desorption layer composed of the above-mentioned organic solvent-based printing ink on the base material 1.

[11] A laminate having at least a base material 1, a desorbing layer made of the organic solvent-based printing ink, and a base material 2.

[12] A method for producing a recycled base material, which comprises a step of immersing a printed matter in a basic aqueous solution.
The printed matter has a base material 1, a desorption layer formed by the organic solvent-based printing ink according to any one of claims 1 to 9, and a pattern layer in this order.
A method for producing a recycled base material, wherein the basic aqueous solution contains 0.5 to 10% by mass of the total basic aqueous solution, and the water temperature of the basic aqueous solution at the time of immersion is 30 to 120 ° C.

[13] A method for producing a recycled base material, which comprises a step of immersing the laminate in a basic aqueous solution.
The laminate has a desorption layer formed by the organic solvent-based printing ink according to any one of claims 1 to 9 and a pattern layer and / or an adhesive layer between the base material 1 and the base material 2. Have
A method for producing a recycled base material, wherein the basic aqueous solution contains 0.5 to 10% by mass of the total basic aqueous solution, and the water temperature of the basic aqueous solution at the time of immersion is 30 to 120 ° C.

Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, parts and% in the present invention represent parts by mass and% by mass.

(Molecular weight and molecular weight distribution)
The weight average molecular weight (Mw), number average molecular weight (Mn) and molecular weight distribution (Mw / Mn) were measured by GPC (gel permeation chromatography) and determined as converted molecular weights using polystyrene as a standard substance.
GPC device: Showa Denko Shodex GPC-104
Column: The following columns were connected in series and used.
Showa Denko's Shodex LF-404 2 pieces Showa Denko's Shodex LF-G
Detector: RI (Differential Refractometer)
Measurement conditions: Column temperature 40 ° C
Eluent: Tetrahydrofuran Flow rate: 0.3 mL / min

(Acid value and hydroxyl value)
In the following, the acid value and the hydroxyl value were measured according to the method described in JIS K0070 (1992).

[Synthesis Example 1] (Preparation of Polyurethane Resin P1)
198.0 PPA (poly (propylene glycol) adipatediol with a number average molecular weight of 2000) while introducing nitrogen gas in a reactor equipped with a reflux condenser, a dropping funnel, a gas introduction tube, a stirrer, and a thermometer. , 2,2-Dimethylolbutanoic acid (DMBA) 13.3 parts, isophorone diisocyanate (IPDI) 76.0 parts, and methyl ethyl ketone (MEK) 200 parts are charged and reacted at 90 ° C. for 5 hours to have a terminal isocyanate group. A resin solution of urethane prepolymer was obtained. To the obtained terminal isocyanate group urethane prepolymer resin solution, 12.2 parts of 2- (2-aminoethylamino) ethanol (AEA), 0.4 parts of ethanolamine (MEA), and 350 parts of isopropyl alcohol (IPA) were added. The mixture was added dropwise at room temperature over 60 minutes and further reacted at 70 ° C. for 3 hours. Further, the solid content was adjusted using 150 parts of MEK.
A polyurethane resin (P1) solution having a solid content of 30%, a weight average molecular weight of 33000, Mw / Mn = 2.9, an acid value of 16.8 mgKOH / g, and a hydroxyl value of 23.2 mgKOH / g was obtained. The polyester polyol ratio in the polyol in P1 is 100% by mass.

The polyurethane resin produced below was adjusted according to synthetic conditions such as dropping amount, dropping rate, temperature control and stirring speed so as to have Mw / Mn and weight average molecular weight described in each table.

[Synthetic Examples 2 to 14 and 16] (Preparation of polyurethane resins P2 to P14 and 16)
Polyurethane resins (P2 to P14, 16) were obtained by the same operation as in Synthesis Example 1 except that the raw materials and the charging ratios shown in Table 1-1 were used. Properties such as Mw, Mw / Mn and acid value are shown in Table 1-2.
The abbreviations of the raw material compounds shown in Table 1-1 not used in Synthesis Example 1 are as shown below.
PMPA: Poly (3-methyl-1,5-pentanediol) with a number average molecular weight of 2000 Adipatediol PCL: Polycaprolactone diol with a number average molecular weight of 2000 (Daicel 220 ester bond concentration: 8.3 mmol / g)
PC: Polycarbonate diol PPG having a number average molecular weight of 2000 and liquid at 25 ° C. having 3-methyl-1,5-pentanediol / 1,6-hexanediol = 9/1: Polypropylene glycol with a number average molecular weight of 2000 IPDA: Isophorone Diamine DBA: Di-n-Butylamine

[Synthesis Example 15] (Preparation of Polyurethane Resin P15)
212.1 parts of PPA, 27.8 parts of DMBA, 60.1 parts of IPDI while introducing nitrogen gas in a reactor equipped with a reflux condenser, a dropping funnel, a gas introduction tube, a stirrer, and a thermometer. 200 parts of MEK were charged and reacted at 90 ° C. for 7 hours. After that, the solid content was adjusted with 150 parts of MEK and 350 parts of IPA, and a polyurethane resin having a solid content of 30%, a weight average molecular weight of 40,000, Mw / Mn = 3.5, an acid value of 35.1 mgKOH / g, and a hydroxyl value of 8.7 mgKOH / g. (P15) A solution was obtained. The polyester polyol ratio in the polyol in P15 is 100% by mass.

[Synthesis Example A1] (Synthesis of Polyester Polyester A1)
In a round-bottom flask equipped with a stirrer, thermometer, water divider and nitrogen gas introduction tube, 54.3 parts of 1,10-decandicarboxylic acid, 45.7 parts of 1,10-decanediol, and tetrabutyl titanate 0. 002 parts were charged, and esterification was carried out for 8 hours under a nitrogen stream at 230 ° C. while removing water generated by condensation. After confirming that the acid value of the polyester was 15 or less, the degree of vacuum was gradually increased by a vacuum pump to complete the reaction. As a result, a polyester polio (A1) having a number average molecular weight of 2000, a hydroxyl value of 56.1 mgKOH / g, and an acid value of 0.3 mgKOH / g was obtained. The ester bond concentration is 4.5 mmol / g, R ¹ has 10 linear carbon atoms, and R ² has 10 linear carbon atoms.

[Synthesis Examples A2 to A17] (Synthesis of Polyester Polyesters A2 to A17)
Polyester polyols A2 to A17 were obtained in the same manner as in Synthesis Example A1 except that the raw materials and the charging ratios shown in Table 2 were used. The linear carbon number and ester bond concentration of R ¹ and R ² are also shown in Table 2.

[Synthesis Example 1a] (Preparation of polyurethane resin U1)
158.7 parts of polyester polyol A1, 15.9 parts of PPG, 27.6 parts of DMBA, while introducing nitrogen gas in a reactor equipped with a reflux condenser, a dropping funnel, a gas introduction tube, a stirrer, and a thermometer. 88.2 parts of IPDI and 200 parts of MEK were charged and reacted at 90 ° C. for 5 hours to obtain a resin solution of a terminal isocyanate group prepolymer. A mixture of 9.1 parts of AEA, 0.5 part of MEA, and 350 parts of IPA was added dropwise to the obtained terminal isocyanate group prepolymer over 60 minutes at room temperature, and further reacted at 70 ° C. for 3 hours. Further, the solid content was adjusted using 150 parts of MEK.
A polyurethane resin (U1) solution having a solid content of 30%, a weight average molecular weight of 45,000, Mw / Mn = 3.9, and an acid value of 34.9 mgKOH / g was obtained. The urethane bond concentration was 1.83 mmol / g, the urea bond concentration was 0.61 mmol / g, and the total of the urethane bond concentration and the urea bond concentration was 2.43 mmol / g. The polyester polyol ratio in the polyol was 90.9% by mass.

[Synthesis Examples 2a to 25a] (Preparation of Polyurethane Resins U2 to U25)
A polyurethane resin (U2 to U25) was obtained by the same operation as in Synthesis Example 1a except that the raw materials and the charging ratios shown in Table 2-1 were used. Properties such as Mw, Mw / Mn, acid value, and binding concentration are shown in Table 2-2.

[Synthesis Example 26a] (Preparation of polyurethane resin U26)
While introducing nitrogen gas in a reactor equipped with a reflux condenser, a dropping funnel, a gas introduction tube, a stirrer, and a thermometer, 141.1 parts of polyester polyol A17, 14.1 parts of PPG, and DMBA27. .7 parts, 92.4 parts of IPDI and 200 parts of MEK were charged and reacted at 90 ° C. for 5 hours to obtain a resin solution of a terminal isocyanate group prepolymer. Next, a resin solution of the obtained terminal isocyanate group prepolymer was added dropwise to a mixture of 9.2 parts of AEA, 15.0 parts of IPDA, 0.4 parts of MEA, and 350 parts of IPA over 60 minutes at room temperature, and further at 70 ° C. 3 Reacted for time. Further, the solid content was adjusted using 150 parts of MEK.
A polyurethane resin (U26) solution having a solid content of 30%, a weight average molecular weight of 35,000, Mw / Mn = 3.3, and an acid value of 35.0 mgKOH / g was obtained. The urethane bond concentration was 1.76 mmol / g, the urea bond concentration was 1.01 mmol / g, and the total of the urethane bond concentration and the urea bond concentration was 2.77 mmol / g. The polyester polyol ratio in the polyol was 90.9% by mass.

[Comparative Synthesis Examples 1 to 4] (Preparation of Polyurethane Resins PP1 to 4)
A polyurethane resin (PP1-4) solution was obtained in the same manner as in Synthesis Example 1a except that the raw materials and the charging ratios shown in Table 3-1 were used.

[Comparative Synthesis Example 5] (Preparation of Polyurethane Resin PP5)
While introducing nitrogen gas in a reactor equipped with a reflux condenser, a dropping funnel, a gas introduction tube, a stirrer, and a thermometer, 132.7 parts of PPA, 29.5 parts of PPG, and 27.7 parts of DMBA. 96.5 parts of IPDI and 200 parts of MEK were charged and reacted at 90 ° C. for 5 hours to obtain a resin solution of a terminal isocyanate-based prepolymer. A mixture of 13.6 parts of AEA and 150 parts of IPA was added dropwise to the obtained terminal isocyanate group prepolymer over 60 minutes at room temperature, and then 10.0 parts of 28% ammonia water and 690 parts of ion-exchanged water were added. By gradually adding to the solvent-type polyurethane resin solution to neutralize it to make it water-soluble, and further distilling off MEK and IPA under reduced pressure, the acid value is 35.0 mgKOH / g, the weight average molecular weight is 43000, and the solid content is 30. % Aqueous aqueous polyurethane resin (PP5) aqueous solution was obtained. However, the acid value in PP5 is a value before neutralization.

[Comparative Synthesis Examples 6 to 7] (Preparation of polyurethane resins PP6 to 7)
A polyurethane resin (PP6 to 7) solution was obtained in the same manner as in Synthesis Example 1a except that the raw materials and the charging ratios shown in Table 3-1 were used.

[Comparative Synthesis Example B1] (Synthesis of Polyester Polyester B1)
Synthesis Example A1 except that 54.3 parts of 1,10-decanedicarboxylic acid was changed to 53.1 parts of icosane diacid and 45.7 parts of 1,10-decanediol was changed to 1,16-hexadecanediol. Polyester polyol B1 having a number average molecular weight of 2000, a hydroxyl value of 56.1 mgKOH / g, and an acid value of 0.3 mgKOH / g was obtained by the same method as in the above. The ester bond concentration is 2.9 mmol / g, R ¹ has 18 linear carbon atoms, and R ² has 16 linear carbon atoms.

[Comparative Synthesis Example 8] (Preparation of Polyurethane Resin PP8)
143.1 parts of polyester polyol B1, 31.8 parts of PPG, 27 parts of DMBA while introducing nitrogen gas in a reactor equipped with a reflux condenser, a dropping funnel, a gas introduction tube, a stirrer, and a thermometer. .7 parts, 88.4 parts of IPDI and 200 parts of MEK were charged and reacted at 90 ° C. for 5 hours to obtain a resin solution of a terminal isocyanate group prepolymer. A mixture of 9.1 parts of AEA and 150 parts of IPA was added dropwise to the obtained terminal isocyanate group prepolymer over 60 minutes at room temperature, and then 10.0 parts of 28% ammonia water and 690 parts of ion-exchanged water were added. By gradually adding to the solvent-type polyurethane resin solution to neutralize it to make it water-soluble, and further distilling off MEK and IPA under reduced pressure, the acid value is 34.9 mgKOH / g, the weight average molecular weight is 48,000, and the solid content is 30. An aqueous solution of% aqueous polyurethane resin (PP8) was obtained. However, the acid value in PP8 is a value before neutralization.

The raw materials and compounding ratios used in the production of the polyurethane resins PP1 to PP8 are shown in Table 3-1. The values of molecular weight, molecular weight distribution, acid value, hydroxyl value, polyester polyol ratio, number of bonds, etc. are shown in Table 3-2.

[Example 1] (Preparation of clear ink S1)
87 parts of polyurethane resin P1 solution (solid content 30%), 5 parts of ethyl acetate (EA), 5 parts of IPA, and 3 parts of silica (hydrophilic silica particles P-73 with an average particle diameter of 3.8 μm manufactured by Mizusawa Industrial Chemicals Co., Ltd.). The clear ink S1 was obtained by stirring and mixing using a disper.

[Examples 2 to 13, 15 to 23] (Preparation of clear inks S2 to S13 and S15 to S23)
Clear inks S2 to S13 and S15 to S23 were obtained by the same method as in Example 1 except that the raw materials and compounding ratios shown in Tables 1-3 and 1-4 were used. The abbreviations in the table of raw materials not used in Example 1 are as follows.
Vinyl chloride resin: Vinyl chloride-vinyl acetate copolymer resin (vinyl chloride: vinyl acetate: vinyl alcohol = 88: 1: 11) (solid content 30%)
Acrylic resin: Styrene-acrylic copolymer resin with a weight average molecular weight of 40,000 and an acid value of 60 mgKOH / g (solid content 30% solution)
Polyethylene particles: High wax 220P manufactured by Mitsui Chemicals, Inc.
Barium Sulfate: Variace B30 manufactured by Sakai Chemical Industry Co., Ltd.

[Example 14] (Preparation of color ink S14)
10 parts of copper phthalocyanine indigo (phthalocyanine LIONOL BLUE FG-7358-G manufactured by Toyo Color Co., Ltd.), 40 parts of polyurethane resin (P5), 3 parts of EA, and 3 parts of IPA are stirred and mixed, and the pigment is further dispersed in a sand mill for 20 minutes, and then further polyurethane 40 parts of the resin solution (P10), 2 parts of EA, and 2 parts of IPA were stirred and mixed to obtain an indigo color ink (S14). The total values are shown for each component shown in Tables 1-3 and 1-4.

[Examples 24 to 26] (Preparation of color inks S24 to S26)
Color inks S24 to 26 were obtained by the same method as in Example 14 except that the raw materials and blending ratios shown in Table 1-4 were used.

(Examples 1a to 26a) (Production of clear inks T1 to T26)
Clear inks T1 to T26 were obtained by the same method as in Example 1 except that the raw materials and compounding ratios shown in Tables 2-3 and 2-4 were used.

[Examples 27a to 29a] (Preparation of color inks T27 to T29)
Color inks T27 to T29 were obtained by the same method as in Example 14 except that the raw materials and compounding ratios shown in Tables 2-3 and 2-4 were used.

(Comparative Examples 1 to 8) (Preparation of inks SS1 to SS8)
Inks SS1 to SS9 were obtained by the same method as in Example 1 except that the raw materials shown in Table 3-3 were used in the blending ratios described.

[Comparative Example 9] (Production of Color Ink SS9)
Color ink SS9 was obtained by the same method as in Example 14 except that the raw materials and blending ratios shown in Table 3-3 were used.

<Creation of printed matter using clear ink S1>
(Print composition A: PET base material / desorption layer / pattern layer)
The clear ink S1 was diluted with an EA / IPA mixed solvent (mass ratio 70/30) so as to be Zahn Cup # 3 (manufactured by Rigosha) for 15 seconds (25 ° C.). Then, a clear ink S1 and PANNECO AM 92 ink (organic solvent-based gravure ink manufactured by Toyo Ink Co., Ltd.) were applied to a corona-treated polyethylene terephthalate (PET) substrate (thickness 12 μm), and a gravure plate having a plate depth of 35 μm was provided. Printing was performed in this order with a gravure printing machine, and the mixture was dried at 50 ° C. to obtain a printed matter as a PET substrate / desorption layer (S1) / pattern layer.

<Preparation of printed matter using each ink obtained in Example or Comparative Example>
For each of the inks obtained in the above Examples or Comparative Examples other than the clear ink S1, printed matter having the same printing configuration was prepared by the same procedure as for producing the printed matter using the clear ink S1.

<Preparation of laminated laminate using clear ink S1>
(Laminate configuration A: OPP base material / desorption layer / pattern layer / adhesive layer / VMCPP base material)
The clear ink S1 was diluted with an EA / IPA mixed solvent (mass ratio 70/30) so as to be Zahn Cup # 3 (manufactured by Rigosha) for 15 seconds (25 ° C.). Then, a clear ink S1 and Rio Alpha S R92 ink (organic solvent-based gravure ink manufactured by Toyo Ink Co., Ltd.) were applied to a corona-treated stretched polypropylene (OPP) film (thickness 20 μm), and a gravure plate having a plate depth of 35 μm was provided. Printing was performed in this order with a gravure proofing two-color machine, and each unit was dried at 50 ° C. to obtain a printed matter having an OPP base material / desorption layer (S1) / pattern layer in this order.
Using a dry laminating machine, a dry laminating adhesive (TM-340V / CAT-29B manufactured by Toyo Morton Co., Ltd.) is applied on the pattern layer of this printed matter, and VMCPP (aluminum vapor deposition unstretched) is applied at a line speed of 40 m / min. It was laminated with a polypropylene film (thickness 25 μm) to obtain a laminated laminate in the order of OPP base material / desorption layer (S1) / pattern layer / adhesive layer / VMCPP base material.

<Preparation of laminated laminate using each ink obtained in Example or Comparative Example>
For each ink obtained in the above Examples or Comparative Examples other than the clear ink S1, laminated laminates having the same laminated structure were obtained by the same procedure as described above.

<Manufacturing of packaging bag using clear ink S1>
(Laminate configuration B: PET base material / desorption layer / pattern layer / adhesive layer / CPP base material)
The clear ink S1 was diluted with an EA / IPA mixed solvent (mass ratio 70/30) so as to be Zahn Cup # 3 (manufactured by Rigosha) for 15 seconds (25 ° C.). After that, clear ink S1 and Rio Alpha S R92 ink (manufactured by Toyo Ink Co., Ltd.) were applied to a corona-treated polyethylene terephthalate (PET) substrate (thickness 12 μm), and two gravure calibration colors equipped with a gravure plate with a plate depth of 35 μm. Printing was performed in this order on a machine, and each unit was dried at 50 ° C. to obtain a printed matter having a PET substrate / desorption layer (S1) / pattern layer in this order.
Using a dry laminating machine, a dry laminating adhesive (TM-250HV / CAT-RT86L-60 manufactured by Toyo Morton Co., Ltd.) is applied on the pattern layer of this printed matter, and CPP (unstretched polypropylene) is applied at a line speed of 40 m / min. It was laminated with a base material having a thickness of 30 μm) to obtain a laminated laminate in the order of PET base material / desorption layer (S1) / pattern layer / adhesive layer / CPP. The laminated laminate was cut into a size of 15 cm × 25 cm, and the edge portion was thermocompression bonded (called heat seal) at 180 ° C. to obtain a packaging bag.

<Preparation of packaging bag using each ink obtained in Example or Comparative Example>
For each ink obtained in the above Examples or Comparative Examples other than the clear ink S1, packaging bags having the same laminated structure were obtained by the same procedure as described above.

<Characteristic evaluation>
The evaluations described below were carried out using the organic solvent-based printing inks obtained in the above Examples and Comparative Examples, their printed matter, laminated laminates and packaging bags. The evaluation results are shown in Tables 1-3 and 1-4, Tables 2-3 and 2-4, and Table 3-3.

<Evaluation of detachability in printed matter>
The printed matter of print configuration A produced in the above Examples and Comparative Examples was cut into 4 cm × 4 cm, immersed in 50 g of a 2% sodium hydroxide (NaOH) aqueous solution, stirred at 40 ° C., washed with water and dried, and then PET. The peelability of the pattern layer from the base material was evaluated.
5 (excellent): The print layer such as the pattern layer is peeled from the 100% PET film within 20 minutes of stirring 4 (Good): The print layer such as the pattern layer is peeled from the 100% PET film within 1 hour over 20 minutes of stirring 3 (Good) Possible): 80% or more and 100% or less of the print layer such as the pattern layer is peeled off from the PET film within 12 hours over 1 hour of stirring 2 (impossible): 20% or more and less than 80% of the print layer such as the pattern layer is separated by 12 hours of stirring. Peeled from PET film.
1 (Inferior): Less than 20% of the printing layer such as the pattern layer was peeled off from the PET film after 12 hours of stirring.
3, 4 and 5 are ranges in which there is no practical problem.

<Evaluation of detachability in laminated laminate>
The laminated laminate of Laminated Structure A produced in the above Examples and Comparative Examples was cut into 4 cm × 4 cm, immersed in 50 g of a 2% sodium hydroxide (NaOH) aqueous solution, stirred at 40 ° C., washed with water and dried. Later, the peelability of the pattern layer from the OPP film was evaluated.
5 (excellent): The print layer such as the pattern layer is peeled from the 100% OPP film within 20 minutes of stirring 4 (Good): The print layer such as the pattern layer is peeled from the 100% OPP film within 1 hour over 20 minutes of stirring 3 (Good) Possible): 80% or more and 100% or less of the print layer such as the pattern layer is peeled off from the OPP film within 12 hours over 1 hour of stirring 2 (impossible): 20% or more and less than 80% of the print layer such as the pattern layer is removed by 12 hours of stirring. Peeled from OPP film.
1 (Inferior): Less than 20% of the printing layer such as the pattern layer was peeled off from the OPP film after 12 hours of stirring.
3, 4 and 5 are ranges in which there is no practical problem.

<Retort resistance evaluation>
The packaging bag of the laminated structure B produced in the above Examples and Comparative Examples was subjected to a retort test at 120 ° C. for 80 minutes, and the laminate strength immediately after the retort and the laminate strength before the retort were compared and evaluated.
5 (excellent): No decrease in laminate strength before and after retort, and laminate strength immediately after retort of 1.0 N / 15 mm or more 4 (Good): Decrease in laminate strength of less than 1.0 N / 15 mm before and after retort Although it can be seen, the laminate strength immediately after retort is 1.0 N / 15 mm or more 3 (possible): The laminate strength is decreased by 1.0 N / 15 mm or more before and after retort, but the laminate strength immediately after retort is 1.0 N. / 15 mm or more 2 (impossible): A decrease in laminate strength of 1.0 N / 15 mm or more is observed before and after retort, and the laminate strength immediately after retort is 0.5 N / 15 mm or more and less than 1.0 N / 15 mm 1 ( Inferior): A decrease in laminate strength of 1.0 N / 15 mm or more was observed before and after the retort, and those having a laminate strength of less than 0.5 N / 15 mm immediately after the retort 3, 4 and 5 are in the range where there is no practical problem.

<Evaluation of dryness>
On a corona-treated PET film (thickness 12 μm), at a temperature of 25 ° C., the bar coater No. The organic solvent-based printing inks obtained in the above Examples and Comparative Examples were applied using No. 4. The dryness was evaluated by touching the finger every 5 seconds immediately after the coating and setting the end point of drying when the stickiness (called tack) disappeared. The bar coater is Miyabar No. 1 manufactured by Daiichi Rika Co., Ltd. 4 was used.
5 (excellent): Dry in less than 15 seconds.
4 (Good): Dry in 15 seconds or more and less than 30 seconds.
3 (OK): Dry in 30 seconds or more and less than 45 seconds.
2 (impossible): Dry in 45 seconds or more and less than 60 seconds.
1 (inferior): Dry in 60 seconds or more.
3, 4 and 5 are ranges in which there is no practical problem.

<Evaluation of substrate adhesion (tape adhesion) in printed matter>
Regarding the printed matter of print configuration A produced in the above Examples and Comparative Examples, a cellophane tape (12 mm width) manufactured by Nichiban Co., Ltd. was attached on the print layer, the tape was slowly peeled off, and the ink film was peeled off suddenly from the middle. The degree of peeling was evaluated.
5 (excellent): The ink film does not peel off at all even if it is peeled off rapidly.
4 (Good): The ink film in an area of less than 25% of the rapidly peeled part is peeled off.
3 (Yes): The ink film in an area of 25% or more and less than 75% of the rapidly peeled portion is peeled off.
2 (impossible): The ink film in an area of 75% or more of the rapidly peeled part is peeled off, or a part of the ink film is peeled off in the slowly peeled part 1 (inferior): Ink in the slowly peeled part 3, 4 and 5 where the coating film is completely peeled off are in a range where there is no practical problem.

<Example 27>
In the above evaluation, the color ink S14 was used, and the printed matter of the print structure A, the laminated body of the laminated structure A, and the packaging bag of the laminated structure B were produced in the same manner except that the pattern layer was not used. The print configuration and the laminated configuration are shown below.
(Printed matter print configuration)
PET substrate / desorption layer (S14)
(Laminated structure of laminated laminate)
OPP base material / desorption layer (S14) / adhesive layer / VMCPP base material (laminated structure of packaging bag)
When the same characteristic evaluation as above was performed using each of the PET base material / desorption layer (S14) / adhesive layer / CPP base material, the desorption property evaluation in the printed matter on the front print: 4, exfoliation in the laminated laminate The release evaluation was 3, the tape adhesion evaluation was 5, the retort resistance evaluation was 5, and the dryness evaluation was 5.

From the above evaluation results, if the organic solvent-based printing ink of the embodiment of the present invention is used, it has good print processing suitability, and in a laminate having a front printing structure and a laminated structure, an alkaline aqueous solution is used to change the ink from a plastic film to ink, etc. It was shown that it can be desorbed and that it exhibits good retort suitability in a laminated structure. Furthermore, it was shown that when the organic solvent-based printing ink of the embodiment of the present invention was used, good substrate adhesion was exhibited in the front printing configuration.

Claims (13)

Detachment for recycling the base material 1 by peeling the design layer and / or the base material 2 from the printed matter or laminate having the base material 1, the desorption layer, and the pattern layer and / or the base material 2 in this order. An organic solvent-based printing ink used to form a delamination.
The organic solvent-based printing ink is an organic solvent-based printing ink containing a polyurethane resin having an acid value of 15 to 70 mgKOH / g and a hydroxyl value of 1 to 35 mgKOH / g as a binder resin. The organic solvent-based printing ink according to claim 1, wherein the polyurethane resin contains a constituent unit derived from a polyol, and the polyol contains at least one selected from a polyester polyol, a polyether polyol, and a polycarbonate polyol. Detachment for recycling the base material 1 by peeling the design layer and / or the base material 2 from the printed matter or laminate having the base material 1, the desorption layer, and the pattern layer and / or the base material 2 in this order. An organic solvent-based printing ink used to form a delamination.
The organic solvent-based printing ink contains a polyurethane resin having an acid value of 15 to 70 mgKOH / g as a binder resin, and the polyurethane resin contains a constituent unit derived from a polyol.
The polyol is an organic solvent-based printing ink containing 50% by mass or more of a polyester polyol having an ester bond concentration of 4 to 11 mmol / g. The organic solvent-based printing ink according to any one of claims 1 to 3, wherein the organic solvent-based printing ink is an organic solvent-based clear ink. The organic solvent-based printing ink according to any one of claims 1 to 4, wherein the polyurethane resin has a molecular weight distribution (Mw / Mn) of 6 or less. The polyester polyol is a condensate of a dibasic acid having a carboxyl group at both ends of the alkylene group (R ¹ ) and a diol having hydroxyl groups at both ends of the alkylene group (R ² ).
Either one of the carbon number that linearly connects the carboxyl groups of the dibasic acid and the carbon number that linearly connects the hydroxyl groups of the diol has 1 to 6 carbon atoms.
The organic solvent-based printing ink according to any one of claims 2 to 5, wherein the alkylene groups (R ¹ ) and (R ² ) are substituted or unsubstituted alkylene groups. The sixth aspect of claim 6, wherein both the number of carbon atoms for linearly connecting the carboxyl groups of the dibasic acid and the number of carbon atoms for linearly connecting the hydroxyl groups of the diol are 1 to 6. Organic solvent-based printing ink. The organic solvent-based printing ink further contains at least one resin selected from the group consisting of a cellulose-based resin, a vinyl chloride-based resin, a rosin-based resin, an acrylic resin, and a styrene-maleic acid copolymer resin, claims 1 to 1. 7. The organic solvent-based printing ink according to any one of 7. The organic solvent-based printing ink according to any one of claims 1 to 8, further comprising an extender pigment. A printed matter having a desorption layer composed of the organic solvent-based printing ink according to any one of claims 1 to 9 on the base material 1. A laminate having at least a base material 1, a desorbing layer made of the organic solvent-based printing ink according to any one of claims 1 to 9, and a base material 2. A method for producing a recycled base material, which comprises a step of immersing a printed matter in a basic aqueous solution.
The printed matter has a base material 1, a desorption layer formed by the organic solvent-based printing ink according to any one of claims 1 to 9, and a pattern layer in this order.
A method for producing a recycled base material, wherein the basic aqueous solution contains 0.5 to 10% by mass of the total basic aqueous solution, and the water temperature of the basic aqueous solution at the time of immersion is 30 to 120 ° C. A method for producing a recycled base material, which comprises a step of immersing the laminate in a basic aqueous solution.
The laminate has a desorption layer formed by the organic solvent-based printing ink according to any one of claims 1 to 9 and a pattern layer and / or an adhesive layer between the base material 1 and the base material 2. Have
A method for producing a recycled base material, wherein the basic aqueous solution contains 0.5 to 10% by mass of the total basic aqueous solution, and the water temperature of the basic aqueous solution at the time of immersion is 30 to 120 ° C.