JPH089197B2 - Print laminating method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a print laminating method.

[Prior Art] As a print laminate for thermocompression bonding a film in which a heat-fusible polymer layer is laminated, a laminate with paper, metal foil, cloth, etc. (Japanese Patent Publication No. 60-36939), a laminate with printing paper (Japanese Patent Publication No. 63-12792, Japanese Patent Laid-Open No. 60-13523)
6 and JP-A-60-184326) are known.

[Problems to be Solved by the Invention]

However, although the above-mentioned conventional print laminate has satisfactory adhesive strength, it is not glossy and has a poor gloss feeling. An object of the present invention is to provide a method for improving the above problems and providing a print laminate having excellent adhesive strength and gloss.

[Means for solving the problem]

The print laminating method of the present invention comprises a print laminating film and a printed body, wherein a heat-fusible polymer layer is laminated on one side of a biaxially oriented polypropylene film, and a heat-fusible polymer layer side of the print laminating film and the printed body. In a print laminating method in which the printing surfaces of the two are faced to each other and pressure fusion is performed by a fusion device,
After preheating to 110 ° C., the print laminating film and the printed material are pressure-fused at 80 to 140 ° C.

The heat fusible polymer in the present invention is not particularly limited as long as it has a heat fusible property, and is not particularly limited, but polyethylene, ethylene copolymer (for example, ethylene acrylic acid copolymer, ethylene methacrylic acid copolymer Polymer, ethylene methyl methacrylate, ethylene methacrylic acid copolymer such as ethylene methyl methacrylate maleic anhydride terpolymer, ethylene vinyl acetate copolymer, ethylene propylene copolymer, ethylene butene copolymer), propylene Examples thereof include butene copolymer, methyl methacrylate copolymer and the like, and a mixture of these may be used. Further, petroleum resin, terpene resin, rosin and the like may be added, and the preferable addition amount is 5 to 35% by weight.
Further, the above-mentioned copolymer or mixture having a main melting point peak at 50 to 110 ° C. is particularly preferable. The thickness of the heat fusion polymer layer is 1 to 30 μm, preferably 4 to 18 μm.

The biaxially stretched polypropylene film of the present invention refers to a film mainly composed of polypropylene (85% by weight or more of propylene component) within a range that does not impair the intended effects of the present invention.
It may be a copolymer of other α-olefins, or may be a mixture of other polyolefins or olefin-based copolymers. Further, it may be a laminate of two or more layers, and the surface layer preferably has lower rigidity or lower melting point than the base layer. The biaxial stretching method may be simultaneous or sequential stretching, but the sequential method is preferred. The thickness of the biaxially oriented polypropylene film is not particularly limited, but is 5 to 100 μm, preferably 10 to 25 μm.

A heat-stabilizing polymer layer, a biaxially oriented polypropylene film, a heat stabilizer, an antioxidant, an antistatic agent, an antiblocking agent, a lubricant (organic or inorganic), an anti-UV agent, a nucleating agent, etc., with an adhesive strength, Within the range that does not reduce the glossiness (for example,
0.01 to 5% by weight) may be added.

The method for laminating the heat-fusible polymer layer on the biaxially oriented polypropylene film is not particularly limited, but it is a coating method, an extrusion laminating method, a laminating and stretching method (coextrusion method, uniaxially stretching and then laminating and stretching). Method) and the like, and of these, the method of stretching after lamination is preferable, and one example is shown below.

Polypropylene is fed to one extruder and the heat-sealing polymer is fed to another extruder, guided to one die and simultaneously extruded and wound on a cooling roll to form a laminated sheet, which is heated 3 to 7 times in the longitudinal direction. Stretching, cooling (in the method of laminating and stretching after uniaxial stretching, at this point, the heat fusion layer polymer is extrusion laminated), heated again and stretched 5 to 15 times in the transverse direction, heat treatment, and if necessary. Heat-relax to obtain a laminated film. Corona discharge treatment is preferably applied to both surfaces of the heat-fusion polymer layer and the polypropylene film.

The printed matter refers to one printed on art paper, coated paper, high-quality paper, Japanese paper, synthetic paper, film or the like, which may be a single body or a laminated body. The printing is not particularly limited, and may be any of gravure printing, offset printing, letterpress printing, intaglio printing, flexographic printing and the like.

In the present invention, the method of preheating the printed material to 40 to 110 ° C. includes a method of contacting the printed material with a heated roll (metal, rubber, ceramic, etc.), a method of heating under a heater such as infrared rays, and a heating furnace. There is a method of passing through, etc., and there is a method of preheating on both sides or one side, and both sides are preferable from the curl surface of the printed material. It is preferable to preheat by the above method immediately before pressure-bonding the print laminating film and the printed body. The temperature to preheat is 40 to 110 ℃, preferably 50 to 100 ℃ from the corrugation of the printed material, curl, heat resistance of printing ink, preheating effect, etc.
Is.

The fusing device used in the present invention is a device for press-fusing the printing surface of the heat-fusible polymer layer and the printed body laminated on one side of the biaxially oriented polypropylene film, using two rolls. There are devices such as pressure welding and pressure welding using a metal endless belt and a roll. A glazing film may be used instead of the metal endless belt. The roll is preferably made of metal (for example, hard chrome plating, stainless steel), ceramic, rubber or the like. When pressure fusion is performed using two rolls, both are metal rolls, only one is a metal roll or ceramic (on the side of the base film layer), and the other is a rubber roll.

When pressure-bonding the print laminating film and the printed material, 80 to 140 ° C. from one side or both sides, preferably 9
Heating to 0 to 130 ° C and press-bonding gives an excellent gloss feeling. The pressure-bonding temperature is preferably 10 ° C or higher, preferably 20 ° C or higher than the melting point of the heat-bonding polymer layer, and is preferably 30 ° C or higher than the melting point of the biaxially oriented polypropylene film of the present invention. Pressurization is usually good at a linear pressure of 20 to 120 kg / cm.

Hereinafter, the method of the present invention will be described with reference to the drawings, but the method of the present invention is not limited to the following method.

FIG. 1 is a schematic side view of an example of a metal endless belt type fusing apparatus that can be used in the method of the present invention. The metal belt 3 is held by the heating roll 4 and the roll 6, the metal belt 3 is rotated counterclockwise by the rotation of both rolls, and the heating roll 4 is set to a temperature of 80 to 140 ° C. The printed material 2 is preheated rolls 11 and 12 set to a temperature of 40 to 100 ° C.
The printed body 2 and the print laminating film 1 which have been preheated by the metal endless belt 3 and the pressure roll are arranged so that the printed surface of the printed body 2 and the heat fusion polymer layer surface of the print laminating film 1 face each other. The pressure-fused laminate is fed while the pressure-fused laminate is fed at a temperature of 80 to 140 ° C., and the biaxially stretched polypropylene film surface moves while being in contact with the metal endless belt 3. The metal belt 3 is cooled by the water shower 7 before reaching the roll 6,
The laminated body is separated from the metal endless belt 3 (pressure-bonding surface of the fusing device) at a temperature of 20 to 80 ° C. at the position A.

FIG. 2 is a schematic side view of an example of a heating and pressure roll type fusing device that can be used in the present invention. Printed body 2 is 40 to 10
Preheated with preheat rolls 11 and 12 set to a temperature of 0 ° C,
Preheated print 2 and print laminating film 1
Between the metal roll 4 (set at a temperature of 80 to 140 ° C.) and the pressure roll 5 so that the printed surface of the printed body 2 and the heat-bonding polymer layer surface of the print laminating film 1 face each other. Supplied, pressure fusion at a temperature of 80-140 ° C,
Pressure fusion is performed.

The methods for measuring and evaluating the physical properties used in the present invention are as follows.

(1) Melting point Using a differential scanning calorimeter (DSC), the temperature is raised to 280 ° C at a heating rate of 20 ° C / min, held for 5 minutes, cooled at the same speed, and then reheated. The melting point is the peak point of the melting curve. When there is one or more peak points, the peak at the largest melting area drawn from the baseline and the curve is the melting point.

(2) Glossiness The glossiness of the heat-sealed print laminate was judged as follows.

◯: Print laminate with smoothness and excellent gloss x: Print laminate with inferior luster with fine "bump" (3) Adhesive force Heat-fused laminated film and printing paper in 180 ° direction It is peeled and measured in units of 1 cm.

(4) Curl The curl at the end of the print laminate heat-sealed to the printing paper (130 g / m ² art paper) (lifting to the film side) was determined.

◯: Good with no curl Δ: Slightly curled at the end X: Large curl at the end (lifted) (5) Flatness The corrugation and unevenness of the heat-sealed print laminate were judged.

◯: No waviness, no dents, good flatness Δ: Wavy, slightly bumpy X: Wavy, rugged and poor flatness [Example] Polypropylene (melt index: 2.0) was supplied to the extruder at 260 ° C Extruded into a sheet with a drum, wound around a drum and cooled, then heated to 120 ° C, stretched 4.5 times in the longitudinal direction and cooled, and ethylene glycol methyl methacrylate copolymer (melting point: 79 ° C) was added to another extruder. From the laminated sheet, the laminated sheet is introduced into a tenter heated to 170 ° C, stretched 10 times in the transverse direction, heat-treated at 165 ° C, and further heat-bonded polymer layer (ethylene methyl methacrylate copolymer) surface Corona discharge treatment, heat fusion polymer layer thickness 5μ
A polypropylene film having a thickness of 20 μm was obtained. The film for print lamination was laminated on a printing paper under the conditions shown in Table 1 using the apparatus shown in FIG. 1 to obtain a print laminate. The obtained print laminate was evaluated for adhesiveness, glossiness and curl. The results are shown in Table 1.

In each of Example 1 and Example 2, the adhesive strength, glossiness, curl and flatness were excellent.

In Comparative Example 1, since the printed body was not preheated, the glossy feeling was inferior. Further, in Comparative Example 2, since the pressure-bonding temperature was high, the flatness was slightly inferior, the curl was large, the printing ink was smeared, and the gloss feeling was not good. Comparative Example 3
The preheating temperature of the printed material was too high, the flatness was poor, and the curl and gloss were poor.

〔The invention's effect〕

 The present invention has the following excellent effects.

(1) Since the printed material is preheated to 40 to 110 ° C, the heat-sealing polymer does not come into contact with the printed material and cools down. Therefore, it is possible to improve the bite and flow to the printed surface, and to obtain a glossy feeling without fine "bump". It is possible to obtain an excellent printed laminate.

(2) Preheat the printed material to 40-110 ℃ and press-bonding temperature to 80-1
Since the temperature is 40 ° C., the film is uniformly and completely fused, and the polypropylene biaxially stretched film is appropriately smoothed to obtain a print laminate with excellent curl-free gloss.

(3) Further, since the layers are completely fused, a print laminate having a sufficiently strong adhesive force can be obtained.

(4) Since the base material layer is a polypropylene biaxially stretched film, it has excellent workability in that it is cut into individual sheets after print lamination. This cutting suitability is particularly excellent in a method of cutting by tension by forming a notch at the end of the film (which can be cut linearly).

[Brief description of drawings]

1 and 2 illustrate a fusing device that may be used in the method of the present invention. 1 ... Film for print lamination, 2 ... Printed body,
3 ... Metal endless belt, 4 ... Heating roll, 5 ...
... Pressure roll, 6 ... Roll, 7 ... Water shower, 8 ...
… Print laminate, 9 …… roll, 10 …… roll, 11 …… preheat roll, 12 …… preheat roll, A …… remove position

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A 1-141029 (JP, A) JP-A 59-39581 (JP, A) JP-A 63-81024 (JP, A) JP-A 59- 12815 (JP, A) JP 63-31736 (JP, A) JP 63-191620 (JP, A)

Claims (1)

[Claims] 1. A film for print laminate comprising a biaxially stretched polypropylene film and a heat-fusible polymer layer laminated on one side thereof and a printed body, the surface of the heat-fusible polymer layer of the print laminating film and a printed surface of the printed body. In the print laminating method in which the printed body is preheated to 40 to 110 ° C, the print laminating film and the printed body are subjected to pressure fusion at 80 to 140 ° C. A print laminating method characterized by wearing.