JP3388623B2 - Thermoplastic resin film with excellent printability - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic resin film having excellent printability, and in particular, a coating film containing a specific compound is formed on a polyolefin film so that the ink transfer property and the ink can be improved even under high temperature and high humidity. The present invention relates to a thermoplastic resin film having improved adhesiveness. INDUSTRIAL APPLICABILITY The thermoplastic resin film obtained by the present invention, particularly synthetic paper, is useful as a paper for outdoor advertisement stickers, labels for frozen food containers, and nameers for industrial products (labels indicating usage and precautions).

[0002]

2. Description of the Related Art Conventionally, as an outdoor advertisement sticker or a label attached to a frozen food container, the water resistance of the sticker or the label paper, which is a coated paper, is poor. The one whose surface was coated with a polyester film was used. In recent years, a polyolefin-based synthetic paper having good water resistance as such a label paper has been attracting attention as a promising material to replace the above polyester film-coated paper. However, such a polyolefin-based synthetic paper is not necessarily satisfactory in offset printability and processability because the polyolefin, which is the raw material resin, exhibits non-polarity and hydrophobicity, and therefore, is suitable for this purpose. It is usually used after surface treatment. As one of such surface treatment methods, a method of applying a coating agent on the surface of a resin film is known. As the coating agent used in the surface treatment method, specifically, it is known to use polyethyleneimine or an ethyleneimine / ethyleneurea copolymer as a primer (coating agent) (Japanese Patent Publication No. 40-42).
No. 12302, Japanese Patent Publication No. 53-6676, JP-A No. 57-
149363).

Further, on the surface of the polyolefin resin film, an antistatic agent comprising (A ') a water-soluble quaternary nitrogen-containing polymer: 100 parts by weight (B') polyethyleneimine, poly (ethyleneimine-urea) and polyamine Polyimine-based compound selected from the group consisting of polyamide-ethylene imine adducts: 20 to 5
00 parts by weight (C ') Epichlorohydrin adduct of polyamine polyamide: 20 to 500 parts by weight (D') Alkali metal salt or alkaline earth metal salt of sodium carbonate, potassium carbonate, etc.
A film having good printability, which is provided with a primer layer mixed in a proportion of 5 to 50 parts by weight, has been proposed (see Japanese Patent Publication Nos. 2-2910 and 5-57110). However, such a polyethyleneimine, or a resin film provided with a primer layer containing an antistatic agent consisting of a quaternary nitrogen-containing polymer and sodium carbonate, potassium carbonate is a film immediately after the primer layer is provided. Although a printed material that can withstand practical use is obtained, if the polyolefin resin film after surface treatment is stored at high temperature before printing, or if it has been stored for more than one year after manufacturing, it is When printing with an ultraviolet curable ink (UV ink) or an offset printing ink, the transfer of the ink may be defective, or the ink adhesion may be unacceptable for practical use.

Therefore, a general formula (I) is used as a printing film for improving the adhesiveness of ultraviolet curable ink.

[0005]

[Chemical 3]

(Where A is

[0007]

[Chemical 4]

Or, it represents a polyamine / polyamide residue, wherein R ^{1 to} R ⁴ are each independently H and have 1 to 2 carbon atoms.
4 is an alkyl group or an alkenyl group, an aliphatic cyclic hydrocarbon group or a benzyl group, at least one of which represents a group other than H, m is 0 to 300, and n, p and q are numerical values of 1 to 300, respectively. Represents In this case, a thermoplastic resin film having excellent printability has been proposed, in which an aqueous solution of a primer, which is a modified polyethyleneimine represented by the formula (1), is applied onto a polyolefin resin film to form a dried coating layer (JP-A-1-141736). reference). But,
This product has excellent transferability and adhesiveness to UV-curable ink, but the transfer of UV-curable ink to a part of the printing film obtained by preparing a primer in the summer under high temperature and high humidity It turns out that something inadequate occurs.

[0009]

Therefore, it has water resistance and antistatic property, and has good transferability and adhesiveness of the ultraviolet curable ink (UV ink) even in summer under high temperature and high humidity.
It is to obtain a thermoplastic resin film having excellent printability.

[0010]

[Means for Solving the Problems]

[Summary of the Invention] The present inventors have conducted intensive studies in view of the above problems, and as a result, the double hydrate salt such as sodium carbonate and sodium sulfite added to the primer was found to be 40 to 80%.
It was found that deliquescent or efflorescence was exerted at a high temperature of ℃ and under a high relative humidity of 50% or more, adversely affecting the primer composed of a water-soluble nitrogen-containing polymer. Not finding a compound that replaces these, to complete the present invention by finding that it is possible to obtain a printing film having good transferability and adhesiveness of ultraviolet curable ink without lowering the antistatic property. It has come. That is, the thermoplastic resin film excellent in printability of the present invention, on the surface of the thermoplastic resin film,
(A) With respect to 100 parts by weight of the water-soluble nitrogen-containing polymer,
(B) A primer layer comprising an alkali metal salt of phosphoric acid, an inorganic compound selected from potassium alum and ammonium alum in a proportion of 2 to 60 parts by weight is formed.

[0011]

[Function] By using a double-hydrate inorganic compound having no deliquescent and deliquescence properties and a primer composed of a water-soluble nitrogen-containing polymer in combination, the inorganic compound swells and modifies such a water-soluble primer even under high temperature and high humidity. In addition, it is not solidified and the antistatic effect is not reduced. Therefore, it is possible to obtain a thermoplastic resin film having excellent transferability and adhesiveness of the ultraviolet curable ink even in the summer under high temperature and high humidity.

[Detailed Description of the Invention] [I] Thermoplastic resin film layer (base material layer) (1) Raw material A thermoplastic resin used as a base material layer in the thermoplastic resin film of the present invention having excellent printability. The thermoplastic resin used as the raw material of the film includes polypropylene, propylene-ethylene copolymer, polyolefins such as polyethylene, nylon-6, nylon-66, nylon-
Examples thereof include polyamides such as 6,10 and nylon-6,12, thermoplastic polyesters such as polyethylene terephthalate and polybutylene terephthalate, and thermoplastic resins such as polycarbonate, polystyrene and polyphenylene sulfide. Among these raw material resins for thermoplastic resin films, nonpolar polyolefin resins are preferably used in order to further exert the effects of the present invention.

(2) Resin Film The thermoplastic resin film may be stretched or unstretched, and may or may not contain inorganic fine powder or organic filler. . However, it is particularly preferable to use a film having a polyolefin resin film containing a fine inorganic powder as a surface layer or a synthetic paper which is a stretched product thereof.

(A) Synthetic paper Such synthetic paper is known, and the details thereof are described in, for example, Japanese Patent Publication Nos. 46-40794 and 49.
-1782, JP-A-56-118437, JP-A-5
Reference can be made to JP-A No. 7-12642 and JP-A No. 57-56224. The most preferable one of the above synthetic papers is a uniaxially stretched polyolefin resin film containing fine inorganic powders such as calcined clay and calcium bicarbonate to cause countless cracks on the surface centering around the fine inorganic powder particles. Made of a film with a semitransparent or opaque layer on the surface,
No. -60411, JP-A No. 61-3748, etc., a synthetic paper which is a laminate having a surface layer on which a polyolefin resin film layer containing substantially no inorganic fine powder is formed. Can be mentioned. The thickness of these synthetic papers and resin films is generally 8 to 500μ.
m, preferably 30 to 150 μm.

(3) Surface Treatment These synthetic papers and films can be subjected to corona discharge treatment and other surface treatments before the primer coating agent is applied to the surface thereof to form a primer layer.

[II] Primer Layer (1) Constituent Components A primer coated on the thermoplastic resin film (base material layer) to form the primer layer of the thermoplastic resin film having excellent printability of the present invention. Is basically composed of (A) component: a water-soluble nitrogen-containing polymer, and (B) component: an inorganic compound selected from alkali metal salts of phosphoric acid, potassium alum and ammonium alum.

(A) Water-Soluble Nitrogen-Containing Polymer (Component (A)) As the water-soluble nitrogen-containing polymer of the component (A), for example, the following compounds (a) to (b) are used. You can (a) Ethyleneimine modified product (Component (A-1)) This polyethyleneimine modified product has the general formula (I)

[0018]

[Chemical 5]

(Where A is

[0020]

[Chemical 6]

It also represents a polyamine / polyamide residue, wherein R ^{1 to} R ⁴ are each independently H and have 1 to 2 carbon atoms.
4 is an alkyl group or an alkenyl group, an aliphatic cyclic hydrocarbon group or a benzyl group, at least one of which represents a group other than H, m is 0 to 300, and n, p and q are numerical values of 1 to 300, respectively. Express with. ). Such a modified polyethyleneimine is a modified polyethyleneimine adduct of polyethyleneimine or polyamine polyamide with a halogenated compound such as an alkyl halide having 1 to 24 carbon atoms, an alkenyl halide, a cycloalkyl halide or a benzyl halide. It was obtained by denaturing it.

Polyethyleneimine The degree of polymerization of the polyethyleneimine is generally 200 to
One of 3,000 is used.

Polyamine polyamide of polyamine polyamide
Adducts of polyethyleneamine include polyamine polyamide, ethylenediamine, diethylenetriamine,
It is obtained by further adding ethyleneimine to a polyamine polyamide obtained by reacting a polyalkylenepolyamine such as triethylenetetramine with a dibasic acid such as adipic acid, glutaric acid or succinic acid. The polyamine polyamide may have any molecular weight, but it is preferably 500 to 20,000. Although the degree of polymerization of the added ethyleneimine may be arbitrary, it is preferably 20 to 3,000.

Modifiers The halides used as the above modifiers are alkyl halides having 1 to 24 carbon atoms, alkenyl halides, cycloalkyl halides, benzyl halides, etc., and specifically, methyl chloride, odor, etc. Examples thereof include ethyl chloride, n-butyl chloride, lauryl chloride, stearyl iodide, oleyl chloride, cyclohexyl chloride, benzyl chloride, allyl chloride and cyclopentyl chloride. Of these, butyl chloride and cyclohexyl chloride are preferably used.

Modification reaction (Production of modified polyethyleneimine
Preparation ) The modification reaction carried out using the above-mentioned modifier is carried out by adding the above-mentioned halide mentioned as a modifier to a polyethyleneimine adduct of polyethyleneimine or polyamine polyamide, and adding water and / or a hydrophilic solvent, if necessary. In coexistence,
At a temperature of 50 to 200 ° C, preferably 80 to 120 ° C,
It is performed by heating with stirring for 5 to 200 hours. Specific examples of the hydrophilic solvent include alcohols such as ethyl alcohol and isopropyl alcohol, glycols such as ethylene glycol and propylene glycol, and cellosolves such as ethylene glycol monoethyl ether and ethylene glycol monoether acetate. It has a solubility in water of 10g / 10
It is preferable to use ethyl alcohol or isopropyl alcohol with 0 g or more of water.

(B) Acrylic polymer containing tertiary nitrogen or quaternary nitrogen (component (A-2)) Acrylic polymer containing tertiary nitrogen or quaternary nitrogen (A-
Examples of 2) include the following components. Component: Monomer general formula (II) selected from compounds represented by the following general formulas (II) to (VIII)

[0027]

[Chemical 7]

General formula (III)

[0029]

[Chemical 8]

Formula (IV)

[0031]

[Chemical 9]

General formula (V)

[0033]

[Chemical 10]

General formula (VI)

[0035]

[Chemical 11]

General formula (VII)

[0037]

[Chemical 12]

General formula (VIII)

[0039]

[Chemical 13]

(Wherein R ⁵ is hydrogen or a methyl group, and R ⁶ and R ⁷ are lower alkyl groups (preferably having 1 to 4 carbon atoms, particularly preferably 1 to 2 carbon atoms). R ⁸ is a saturated or unsaturated alkyl group having 1 to 22 carbon atoms or a cycloalkyl group, X ⁻ is a quaternized N ⁺ counter anion (for example, a halide (especially chloride)), and M is Alkali metal ions (particularly sodium, potassium or lithium) and A represents an alkylene group having 2 to 6 carbon atoms. Further, a quaternary nitrogen-containing monomer (I
II), (V) and (VII) are precursors ((II), (IV) and
It goes without saying that it can be allowed to exist in the polymer by polymerizing in the form of (VI)) and then quaternizing with a cationizing agent such as alkyl halide, dimethylsulfate, monochloroacetic acid ester and the like. Absent. Furthermore, the salt (MX) formed by the alkali metal ion (M) and the counter anion (X) can be removed by filtration, ion exchange or the like, if necessary. )

Component: (meth) acrylic acid ester 6-80% by weight of acrylic acid ester or methacrylic acid ester represented by the following formula

[0042]

[Chemical 14]

(In the formula, R ⁹ represents an alkyl group having 1 to 24 carbon atoms, an alkylene group, or a cycloalkyl group.) Specific examples include butyl acrylate, capryl acrylate, and stearyl methacrylate.

Ingredients: Other hydrophobic vinyl monomers
0 to 20% by weight As the hydrophobic vinyl monomer, styrene, vinyl chloride or the like can be used.

Components: Those obtained by copolymerizing the above-mentioned components.

Among these (A-2) component tertiary nitrogen- or quaternary nitrogen-containing acrylic polymers, particularly preferable antistatic agent polymers include the component monomers described above.
(VII) in which X ⁻ is Cl ^−, which is sold by Mitsubishi Petrochemical Co., Ltd. under the trade name of “Saftomer ST1000”.

(C) Polyamine polyamide / epichlorohydrin adduct (Component (A-3)) This polyamine polyamide / epichlorohydrin adduct
(A-3) is a water-soluble, cationic thermosetting resin obtained by reacting a polyamide with epichlorohydrin from a saturated dibasic carboxylic acid having 3 to 10 carbon atoms and a polyalkylene polyamine. Details of such a thermosetting resin are described in JP-B-35-3547. A specific example of the saturated dibasic carboxylic acid having 3 to 10 carbon atoms is a dicarboxylic acid having 4 to 8 carbon atoms, particularly adipic acid. Specific examples of the polyalkylene polyamine include polyethylene polyamine, particularly ethylene diamine, diethylene triamine and triethylene tetramine, and diethylene triamine is particularly preferable.

(D) Mixing ratio These water-soluble nitrogen-containing polymers (A-1), (A-2), (A-
3) may be used singly or in combination of two or more kinds, and is preferably a water-soluble tertiary or quaternary nitrogen-containing polymer (A-2) per 100 parts by weight of the modified polyethyleneimine (A-1). )
50-400 parts by weight of water-soluble polyamine polyamide
It is preferable to use a mixture in which epichlorohydrin adduct (A-3) is mixed in a proportion of 50 to 150 parts by weight, since it is possible to provide printing having further excellent heat resistance and antistatic properties.

(B) Inorganic compound selected from alkali metal salts of phosphoric acid, potassium alum and ammonium alum (component (B)) The antistatic performance of the water-soluble nitrogen-containing polymer (primer) of component (A) above is improved. As an inorganic compound (double salt) selected from alkali metal salts of phosphoric acid (B) component, potassium alum and ammonium alum, which are blended to improve the transferability and adhesiveness of the ultraviolet curable ink, Sodium pyrophosphate (Na ₄ P ₂ O ₇ · 10H ₂ O), sodium tripolyphosphate (Na ₅ P ₃ O ₁₀ · 6H ₂ O), primary sodium phosphate (NaH ₂ PO ₄ · 2H ₂ O), potassium alum ( KAl
(SO ₄ ) ₂・ 12H ₂ O), ammonium alum (Al
(NH ₄ ) (SO ₄ ) ₂ · 12H ₂ O) and the like. In addition to the above inorganic compounds, zinc nitrate (Zn (N
_{O 3) 2 · 6H 2 O} )) also has the effect of improving antistatic properties, one coated as a primer layer of a thermoplastic resin film since it is toxic, the safety in use Not suitable as it causes problems. Among inorganic compounds (double salt), when using sodium carbonate, sodium sulfate, sodium sulfite, sodium thiosulfate, barium hydroxide, sodium metasilicate, there is efflorescence, and when using magnesium chloride or magnesium nitrate Is not preferable because it has deliquescent.

(C) Amount Ratio The content of the inorganic compound (double hydrate) selected from the alkali metal salt of phosphoric acid, the potassium alum, and the ammonium alum of the component (B) is the nitrogen-containing polymer of the component (A). The amount is 2 to 60 parts by weight, preferably 10 to 40 parts by weight, based on 100 parts by weight. If the compounding amount of the double hydrate of the component (B) is less than 2 parts by weight, the effect of improving the antistatic property is small. On the other hand, if it exceeds 60 parts by weight, the adhesiveness of the UV ink is deteriorated.

(D) Other compounding components (optional components) The primer is selected from the above-mentioned water-soluble nitrogen-containing polymer as the component (A) and the alkali metal salt of phosphoric acid as the component (B), potassium alum and ammonium alum. Besides adding an inorganic compound, a water-soluble organic solvent such as ethyl alcohol or isopropyl alcohol, a surfactant, a water-soluble polymer, a fine inorganic powder substance, and other auxiliary materials may be contained.

(2) Preparation of primer This primer generally has a solid content of 0.1 to 1
It is used as an aqueous solution having a concentration of 0% by weight, preferably 0.1 to 5% by weight. Further, the coating amount on the thermoplastic resin film is generally 0.005 to 10 g / m ² in terms of solid content,
It is preferably 0.02 to 5 g / m ² .

(3) Method of applying primer As a method of applying the primer, a usual application method such as a roll, a blade, an air knife, and a size press can be adopted.

[III] Printing A thermoplastic resin film having a primer layer formed on the surface of the thermoplastic resin film layer (base material layer) thus obtained can be used for solvent type offset printing, gravure printing and flexographic printing. Of course, UV offset printing (UV curable offset printing) is also possible.

[0055]

EXAMPLES The present invention will be described in more detail with reference to the following experimental examples. The raw materials and evaluation methods used in these experimental examples were as shown below. [I] mean particle size 1.5μm to raw material (1) Preparation Example 1 Synthesis paper thermoplastic resin film thermoplastic resin film (P-1) Melt index (MI) 0.8 polypropylene (melting point 164 ° C.) 12% by weight of heavy calcium carbonate (based on the total weight with polypropylene) was mixed and kneaded with an extruder set at 270 ° C., then extruded into a sheet and cooled by a cooling device. A non-stretched sheet was obtained. This sheet is 140 ℃
After heating to the temperature of, the film was stretched 5 times in the machine direction. 49% by weight of polypropylene having an MI of 4.8, 5% by weight of maleic acid (modified monomer) -modified polypropylene having a maleic acid content of 0.5% by weight, and 46% by weight of calcium carbonate having an average particle diameter of 1.5 μm are mixed. 2% of the composition (A ') prepared (0.05 parts by weight of the modified monomer per 100 parts by weight of the filler).
Melt-kneaded with an extruder set at 70 ° C, and M
55% by weight of polypropylene having an I of 4.0 and an average particle size of 1.
A composition (B ') mixed with 45% by weight of calcium carbonate of 5 μm was melt-kneaded with another extruder set at 270 ° C. and laminated in a die, and the laminate contains the modified polypropylene. A five-layer laminate (A ′ / B ′ / C ′ / B ′ / A ′) was obtained by coextruding both sides of the longitudinally 5 × stretched sheet obtained above so that the layers were on the outside. The five-layer laminate was then heated to 155 ° C. and then laterally 7.5.
The film is stretched twice to form a five-layer laminated film (thickness: 20
μm / 5 μm / 50 μm / 5 μm / 20 μm) was obtained.

Example 2 Synthetic paper (P-2) 79% by weight of polypropylene having a melt index (MI) of 0.8 and 5% by weight of high density polyethylene were mixed with 16% by weight of heavy calcium carbonate having an average particle diameter of 1.5 μm. The composition (C ′) was kneaded with an extruder set at 270 ° C., extruded into a sheet, and cooled with a cooling device to obtain an unstretched sheet. The sheet was heated to a temperature of 140 ° C. and then stretched 5 times in the machine direction. A polypropylene (A ′) having an MI of 4.0 and a composition (B ′) obtained by mixing 45% by weight of calcium carbonate having an average particle diameter of 1.5 μm with polypropylene having an MI of 4.0 are prepared.
Sheets melt-kneaded by separate extruders set at 0 ° C., laminated in a die and co-extruded so that (A ′) is on the outside,
After being laminated on both sides of the longitudinally stretched 5 times sheet obtained above and then cooled to a temperature of 60 ° C., about 160
After heating to a temperature of ℃, heated to a temperature of 165 ℃, stretched 7.5 times in the transverse direction with a tenter, annealed at a temperature of 165 ℃, cooled to a temperature of 60 ℃, The part is slit to form a five-layer structure (A '/ B' / C '/
B ′ / A ′: 30 μm / 3 μm / 64 μm / 3 μm / 3
0 μm) of synthetic paper was obtained.

[0057] (2) Preparation Example 1 Polyethyleneimine modified product of the primer water-soluble nitrogen-containing polymer (A-1) of a stirrer, a reflux condenser, a thermometer and a four-necked flask equipped with a nitrogen gas inlet A 25% by weight aqueous solution of an ethyleneimine adduct of polyamine / polyamide (manufactured by BASF, trade name “Polymin SN”) 100 minutes, 10 parts of n-butyl chloride and 10 parts of isopropyl alcohol were added, and the mixture was stirred under a nitrogen stream to give 80. The modification reaction was carried out at a temperature of ° C for 20 hours. The obtained polymer aqueous solution having a concentration of 20.8%
A-1.

Example 2 Production of polyethyleneimine modified product (A'-1) A- except that 13 parts by weight of allyl chloride was used in place of 10 parts of n-butyl chloride in the production of A-1.
A polymer aqueous solution having a concentration of 19.5% was obtained in the same manner as in the production of A-1.

Example 3 Polyethyleneimine modified product (A ″ -1)
Production of A-1 The same procedure as in the production of A-1 except that 13 parts by weight of cyclopentyl chloride was used in place of 10 parts of n-butyl chloride in the production of A-1 above, and a polymer having a concentration of 19.5% was used. A ″ -1 was obtained from the aqueous solution.

Quaternary nitrogen-containing acrylic resin (A-2 ) manufactured by Mitsubishi Yuka Co., Ltd. under the trade name of "Saftomer ST-320"
0 ”was used. This one is

[0061]

[Chemical 15]

The molecular chain contains

Polyamine polyamide epichlorohydric
Adduct (A-3) Product name "WS-570" manufactured by Dainippon Ink and Chemicals, Inc.
Was used.

Inorganic compound (double hydrate) (B) As an inorganic compound, sodium pyrophosphate, potassium alum, ammonium alum, sodium carbonate (Na ₂ CO ₃ .10H ₂ O)
Alternatively, sodium sulfate (Na ₂ SO ₄ · 10H ₂ O) was used.

[II] Evaluation Method The ink transfer property and ink adhesion property of the ultraviolet curable ink were evaluated by the following measuring methods. (1) Ink adhesion measurement A polypropylene resin film coated with a primer coating agent was stored for 3 days in an atmosphere of 40 ° C. and 80% relative humidity, and then UV curable ink (Toka Dye Chemical Industry Co., Ltd.) Best Cure-161) manufactured by RI Co., Ltd. was developed with an RI tester (manufactured by Akira Seisakusho Co., Ltd.) to a color of about 3 g / m ^2, and 8
10 cm below one 0 W / cm high-pressure mercury lamp,
After drying by irradiating 10 passes at a speed of m / min, Nichiban Co., Ltd. adhesive tape product name "Cellotape LP-24" was attached to the printed surface and lightly pressed with a ball-shaped gauze. While rubbing 5 times, the tape was quickly peeled off to evaluate the ink adhesiveness. A: Transfer ink 0 to 5% peeled off. (No problem in practical use) Good: 5 to 25% of the transfer ink was peeled off. (No practical problem) □: Transfer ink 25 to 50 was peeled off. (No problem in practical use) Δ: 50 to 100% of the transfer ink was peeled off. (There is a problem in practical use) x: The transfer ink peeled off even if the tape was slowly peeled off. (There is a problem in practical use)

(2) Measurement of Ink Transferability A polypropylene resin film coated with a primer coating agent was stored at a temperature of 40 ° C. and a relative humidity of 80%, and then the above-mentioned Best Cure-161 was measured by an RI tester manufactured by Meisei Seisakusho. Print the ink (Sumi) so that it normally rides at 1.5 g / m ^2, and print it at a temperature of 40 ° C and relative humidity of 80%.
After storing in the room for 3 days, the printed surface was measured for light reflection density (Macbeth density) using a Macbeth densitometer manufactured by Columogen, USA. Those with a Macbeth concentration of 1.5 or more are accepted.

[III] Experimental Example Example 1 In 100 parts by weight of an aqueous solution of primer coating agent, each component and water were weighed so that the effective component amount (evaporation residual amount) of each component would be the following composition. The mixture was stirred to prepare a primer coating aqueous solution. Component (A-1): 0.5 parts by weight Component (A-2): 0.5 parts by weight Component (A-3): 0.5 parts by weight Component (B) Sodium pyrophosphate: 0.2 parts by weight Heat After corona discharge treatment on both surfaces of the plastic resin film (P-1), the primer coating agent solution was applied on both surfaces by a roll so that the evaporation residue amount was 0.06 g / m ² on one surface, It was dried at a temperature of ° C to form a film and wound. As shown in Table 1, the ink transferability and the ink adhesiveness of the obtained film due to the ultraviolet curable ink were at a practically acceptable level even under high temperature and high humidity. Further, the change in the surface specific resistance value when the relative humidity was changed at a temperature of 20 ° C. was measured, and the result is shown in FIG.

Examples 3 and 5 and Comparative Examples 1 and 3 Instead of sodium pyrophosphate of Example 1 as the double salt of the component (B), potassium alum (Example 3), ammonium alum (Example 5), The UV offset printability of the printing film was evaluated in the same manner as in Example 1 except that sodium carbonate (Comparative Example 1) or sodium sulfate (Comparative Example 3) was used. The obtained results are shown in FIG. 1 and Tables 1 and 2.

Examples 2, 4 and 6 and Comparative Examples 2 and 4 Example 1 or Examples 3 and 5 above and Comparative Example except that the addition amount of the double hydrate was changed from 0.2 part by weight to 0.6 part by weight. Examples 1 and 3
The UV offset printability of the printing film was evaluated in the same manner as in. The obtained results are shown in Tables 1 and 2.

Examples 7 to 11 and Comparative Examples 5 to 6 The above synthetic paper (P-2) was used as a resin film, and the components (A-1), (A'-1) or (A ''-1) 1.5 parts by weight of component (B) Double hydrate The printability of the UV offset ink was evaluated in the same manner as in Example 1 except that 0.4 parts by weight of the active ingredient was used. The results obtained are shown in Table 3.

Examples 12 to 13 and Comparative Examples 7 to 11 Printing resin films were obtained in the same manner as in Example 1 except that the double hydrate added was changed as shown in Table 4. The printability was evaluated. The results obtained are shown in Table 4.

[0072]

[Table 1]

[0073]

[Table 2]

[0074]

[Table 3]

[0075]

[Table 4]

[0076]

EFFECT OF THE INVENTION The thermoplastic resin film of the present invention, which has excellent printability, has excellent transferability and adhesion of the UV curable ink even under high temperature and high humidity, so that it can be used for outdoor advertisement stickers and frozen food containers. It is ideal as a paper for labels and labels for industrial products (labels that describe usage and precautions), and is an extremely useful material industrially.

[Brief description of drawings]

FIG. 1 is a diagram showing the relationship between relative humidity and surface resistivity of a printing resin film of the present invention at a temperature of 23 ° C.

Continuation of the front page (56) References JP-A-60-135233 (JP, A) JP-A-1-141736 (JP, A) Special Table 8-508453 (JP, A) (58) Fields investigated (Int .Cl. ⁷ , DB name) C08J ⁷ /04-7/06 B05D 7/04 B32B 27/00-27/42 C09D 1/00-201/10

Claims (2)

(57) [Claims] 1. A thermoplastic resin film having a surface on which (A) 100 parts by weight of a water-soluble nitrogen-containing polymer, (B) an inorganic compound selected from alkali metal salts of phosphoric acid, potassium alum and ammonium alum. A thermoplastic resin film having excellent printability, characterized in that a primer layer formed by mixing in a proportion of 2 to 60 parts by weight is formed. 2. A nitrogen-containing polymer has the general formula (I): (In the formula, A is Alternatively, it represents a polyamine / polyamide residue, and R ^{1 to} R ⁴
Are each independently H, an alkyl group or an alkenyl group having 1 to 24 carbon atoms, an aliphatic cyclic hydrocarbon group or a benzyl group, at least one of which represents a group other than H, m is 0 to 300, n, p and q are each 1 to 30
It is represented by a numerical value of 0. The thermoplastic resin film having excellent printability according to claim 1, which is a modified polyethyleneimine represented by the formula (1).