JPH10137649A - Method and apparatus for making composite film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain strong adhesive strength even by low-speed working by a method in which in the production of a composite film by solventless lamination, an impression roller for applying an adhesive on a backing film is used also as a roller of a laminate part which presses the backing film and a laminated film. SOLUTION: An adhesive 4 is supplied to heated feed rollers 13, 14 and transferred to a coating roller 12 which heated the adhesive 4. Next, a backing film 1 is passed through the clearance between it and a heated impression roller to be coated with the adhesive 4. Moreover, in a laminate part 20, a laminated film 2 is pressed and laminated by the impression-lamination roller 11 and a lamination roller 16 to constitute a composite film 3. On this occasion, a coating part 21 and a laminate part 20 are constituted integrally, and the roller 11 out of two lamination rollers 11, 12 is installed to be used as an impression roller. Therefore, the wetting of the adhesive 4 is improved, reducing a press time in lamination.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a laminating step (also referred to as non-sol lamination) using a solvent-free adhesive for producing a composite film using an adhesive composed of a non-volatile component. )
The present invention relates to a film composite apparatus and a composite film manufacturing method for processing a film at a high speed, in which the films are in close contact with each other without bubbles and stable bonding is performed at a high speed.

[0002]

2. Description of the Related Art Conventionally, in a process of manufacturing a composite film by using non-solami, an adhesive used in the process is:
In order to maintain the viscosity required for coating in a state where no solvent is contained, an adhesive is heated or prepared to have a low viscosity at room temperature and applied to a base film. Further, the adhesive is a base film or a bonding film (a film bonded to a base film coated with an adhesive, and similarly described below).
In order to improve the wetting of the composite film, a laminating roller was heated, and the two films were closely adhered and stuck from both sides to produce a composite film.

[0003] Heating from the laminating roller side requires a certain time for heat transfer because it is carried out through a film, and has become a rate-limiting factor when increasing the processing speed. In addition, when the processing speed is increased, the temperature of the adhesive may not be sufficiently increased, the wetting of the adhesive and the film may be insufficient, and the viscosity of the adhesive layer may be high, so that the adhesion of the two films may be insufficient. The desired adhesive strength could not be obtained due to non-uniformity and air bubbles mixed between the composite films. In addition, the adhesive coated with low viscosity has low initial adhesion, and streaky floating between the films (non-adhesion part,
Tunneling) occurs, and not only the appearance but also the function of the composite film cannot be satisfied.

[0004] The above-mentioned decrease in adhesive strength due to air bubbles, tunneling, or high-speed processing is more pronounced than when a reactive (heat-curing, moisture-curing) adhesive is used, in which the adhesive cures over time. This phenomenon is more often observed when an ionizing radiation-curable resin such as an electron beam or an ultraviolet ray that is cured immediately after joining is used. In order to improve these phenomena, it has been practiced to increase the coating amount of the adhesive or to use a low-viscosity adhesive. However, increasing the coating amount of the adhesive increases the material cost, eliminates the advantage of increasing the processing speed, and in some cases, increases the rigidity of the composite film, causing cracks and breaks. In addition, lowering the viscosity of the adhesive can increase the processing speed, but causes problems such as insufficient adhesion and wetting immediately after lamination, foaming of the multilayer film, and failure to obtain the desired adhesive strength. However, there is a problem that stable bonding is difficult.

[0005] Further, it has been attempted to solve the above problem by heating the composite film while maintaining the close contact state by holding it on a heating drum or the like after bonding. However,
In order to raise the temperature of the composite film to an appropriate temperature and bring the composite film into close contact with each other, a large heating device is required, and there is a problem that equipment costs increase.

As shown in FIG. 4, the conventional non-sol lami applies the adhesive 4 transferred to the coating roller 12 quantitatively from the feed rollers 13 and 14 to the base film 1 using the impression roller 11P. Then, the laminating section 20 provided at a fixed distance from the coating section has two layers.
The composite film 3 was formed by being inserted between the laminating rollers 16 of the book, and closely adhered and stuck. Therefore, the temperature of the adhesive that was heated in the coating section decreases during traveling,
Since the temperature was normal, wetting of the base film and the laminated film was not always satisfactory. At this time, the laminating roller 16 was also heated, but the temperature of the adhesive 4 was not sufficient, and the base film 1 was not heated.
Adhesion between both films is insufficient due to poor wettability with lamination film 2 and high viscosity (insufficient adhesion area)
In this case, bubbles were generated and sufficient adhesive strength could not be obtained.

Heating a film (adhesive on a base film) by providing a heater 18 in the same manner as in the conventional method of laminating in a laminating section 20 provided at a fixed distance from the coating section shown in FIG. When the processing speed is as low as about 30 to 50 m / min, an effect contributing to the improvement of the adhesive strength can be recognized. However, the processing speed is 50 m / min.
As described above, in particular, at a high speed of 100 m / min or more, the heating temperature cannot reach the adhesive 4 uniformly, and the base film 1 and the bonding film 2 adhere to each other with the low-temperature adhesive 4. Therefore, it was not possible to obtain an adhesive strength at the time of low-speed processing that can uniformly heat the adhesive.

In order to proceed with high-speed processing, it is necessary to rapidly raise the heating temperature of the laminating section to raise the film temperature and the adhesive temperature to desired temperatures. However, suddenly increasing the heating temperature requires heating with a higher temperature heater, which causes the film temperature, especially its surface temperature, to rise sharply, causing temperature unevenness inside the film and causing the film heat to increase. Problems such as shrinkage and curling of the composite film occurred.

[0009]

SUMMARY OF THE INVENTION The present invention provides a low-speed, low-speed method for applying a stable adhesive at a high speed and producing a composite film free from defects such as foaming and tunneling after lamination. It is an object of the present invention to provide a film composite device and a composite film composite device at a high speed of 100 m / min or more, and a method of manufacturing the same.

[0010]

Means for Solving the Problems In order to achieve the above object, the present invention relates to a method for producing a composite film using non-solami, wherein an impression roller for applying the adhesive to a base film is bonded to the base film. This is a composite device of a film that also serves as a roller of a laminating unit that presses the film. Also, using a composite device of the above film,
This is a method for producing a composite film in which an adhesive feed roller and a coating roller are heated, the heated adhesive is applied to a base film, and the laminated film is laminated. Then, an offset roller, a coating roller, and an impression roller that transfer the adhesive from the feed roller (hereinafter, parts such as a roller that supplies and applies the adhesive to the base film are collectively referred to as a coating unit.) And a method of manufacturing a composite film in which a laminating roller portion is heated to continuously heat an adhesive, and a base film and a bonding film are bonded. And the said adhesive is the manufacturing method of the composite film using the adhesive hardened | cured from ionizing radiation-curable resin.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION As shown in FIG. 1, a non-solami composite film according to the present invention is manufactured by an impression roller 11 for applying an adhesive 4 in a coating section 21 to a substrate film 1 by using an impression roller 11. And laminating film 2
Roller 16 of laminating section 20 for pressing
It is a composite device of a film used together with. Further, the adhesive 4 heated with the feed rollers 13 and 14 and the coating roller 12 is applied to the base film 1 using the composite device for the film, and the adhesive film 4 is bonded to the bonding film 2. This is a method for producing a composite film 3. Then, as shown in FIG. 2, the offset roller 15 for transferring the adhesive 4 from the feed rollers 13 and 14, the coating roller 12, the impression roller 11, and the laminating roller unit 20 are heated to continuously heat the adhesive 4. This is a method for producing a composite film 3 in which a base film 1 and a bonding film 2 are adhered and bonded to each other. The method for manufacturing the composite film 3 uses an adhesive in which the adhesive 4 is cured from an ionizing radiation-curable resin.

As shown in FIG. 3, the adhesive 4 determined by the gravure plate 17 and the doctor 19 is applied to the offset roller 1.
The composite film 3 is manufactured by applying a coating to the base film 1 using the heated impression roller 11, and then laminating the impression film 11 and the laminating roller 16.

The conventional non-solami adhesive shown in FIG. 4 is obtained by quantitatively measuring the amount of the adhesive 4 transferred to the coating roller 12 by the coating roller 12 at the normal temperature.
Coating the base film 1 with P and laminating part 2
At 0, it was inserted between the laminating rollers 16 and closely adhered and stuck to form the composite film 3. At this time, the laminating roller 16 and the surface of the adhesive 4 were also heated. However, since the heating is not performed uniformly, there is unevenness in the wetting between the adhesive 4 and the base film 1 and the bonding film 2, and the adhesion between the two films is insufficient due to the high viscosity. , Bubbles and tunneling had occurred. The heating unit 18 is laminated by a conventional method of laminating a coating unit 21 and a laminating unit 20 provided at a fixed distance shown in FIG.
Heating the film (adhesive layer) using the above method has an effect of improving the adhesive strength at a low processing speed of about 30 to 50 m / min. However, at a high processing speed of 100 m / min or more, heating is
The adhesive 4 could not reach the required temperature, the adhesive could not be uniformly applied, and the base material 1
And the bonding film 2 are adhered and bonded. Therefore, it was not possible to obtain an adhesive strength at the time of low-speed processing that can uniformly heat the adhesive.

The impression roller 11 of the present invention comprises:
By being located in the laminating unit 20, the adhesive 4 heated in the coating unit 21 is in contact with the bonding film 2 before being cooled, and the wetting with the bonding film quickly occurs.
And it can be performed uniformly. Therefore, this method is particularly suitable for non-solami using an ionizing radiation-curable resin in which the adhesive is instantaneously cured.

The base film and the laminated film used in the present invention are not particularly limited to materials, and include polyester, polypropylene, polyethylene, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic ester. Stretched and unstretched films produced from thermoplastic resins such as copolymers, ionomers, polyamides, polycarbonates, polyvinyl chloride, and polyvinyl alcohol are used according to the purpose.

In addition to plastic films, synthetic paper, coated paper, metal foils of aluminum, lead, iron, etc., films obtained by coating the above films with a barrier material such as polyvinylidene chloride, or vapor deposition of aluminum or silicon oxide A film that has been subjected to corona discharge treatment, flame treatment, plasma treatment, etc.
Alternatively, a multilayer film in which these are laminated can be selected according to the application. The thickness of the film is determined by the performance of the processing machine, and the adhesion is a problem of the interface between the films and is not particularly limited. 1 to 1000 μm
Can be arbitrarily used according to the purpose and purpose. Also,
As described above, since the temperature of the film can be gradually increased, the film is easily deformed at a relatively low temperature, and is suitable for processing a stretched film of polyethylene or polyvinyl chloride.

When an adhesive composed of an electron beam-curable resin is used for a film containing a conductive metal foil or a metal-deposited film, there is a danger of ignition due to electric discharge, so that it is necessary to take sufficient measures.

In the present invention, the base film before applying the adhesive, the base film provided with the adhesive and / or the laminated film may be prepared by laminating the film and / or the adhesive with a heating machine or a heating roller before lamination. Can be heated. Therefore, warm air on the film (adhesive) side of the laminating part,
It is preferable to provide a heater using infrared rays, high frequency waves, or the like.

Hereinafter, the coating section / laminating section of the present invention will be described in more detail. The application of the adhesive for non-sol lami is performed by, for example, four rolls as shown in FIG.
That is, the adhesive 4 is supplied to the tops of the heated feed rollers 13 and 14, the adhesive 4 measured by the feed roller 13 is transferred to the heated coating roller 12, and then the heated impression roller 1 is heated as desired.
1 and an adhesive 4 is applied through the base film 1;
Further, in the laminating section 20, the laminating film 2 is closely adhered and laminated by the impression roller / laminating roller 11 and the laminating roller 16 to form the composite film 3. In this case, the film composite apparatus shown in FIG. 1 is different from the conventional non-sol lami in that the coating unit 21 and the laminating unit 20 are integrally formed, and one of the two laminating rollers is used. Is also used as an impression roller.

Each of the above rollers is a feed roller 13,
14, surface materials of the coating roller 12 and the impression roller 11 are rubber (natural rubber, synthetic rubber),
A metal (iron or aluminum roller or a roller obtained by chrome-plating these rollers if necessary), rubber and metal, or any combination of metal, rubber, metal and rubber may be used. The surface temperature of each roller is determined by the type and properties of the film and the adhesive, but is preferably set to 40 to 120C. If the temperature is lower than 40 ° C, the effect of heating is small. May cause.

[0021] The width of the roll, in the conventional non-sol lami,
Although the impression roller is set according to the base film, the present invention sets the coating roller 12 according to the width of the base film because the impression roller also functions as a laminating roller. Usually, the width is equal to or slightly smaller than the width of the base film.

The coating and laminating sections composed of the five rolls shown in FIG. 2 are carried out in the same manner as in the case of the four rolls described above. In this case, although the number of rollers is one, there is an advantage that the adhesive can be spread by the offset roller 15 and a small amount can be uniformly applied. The supply of the adhesive in FIGS. 1 and 2 is performed by the top feed, but may be performed by the bottom feed or another method.

Coating using a gravure plate is an advantageous method for processing control because the amount of coating and the amount of coating are determined by the shape of the plate. However, when it is applied to non-sol lami, there is a problem that since the cells of the gravure plate appear on the coated surface, foaming occurs on the appearance and a white and cloudy composite film is easily formed. In order to solve this, a gravure offset method using a reverse method has been used.

In the present invention, the supply of the adhesive to the gravure plate is as follows.
Although the doweling method is illustrated, the supply may be performed by any method such as a normal application roller method and a nozzle method, and can be appropriately selected according to the viscosity and temperature of the adhesive. When a gravure plate is used, the coating width can be regulated by the width of the concave portion of the plate. However, usually, the offset roller 15C determines the coating width. Become.

When a gravure plate is used, the coating section and the laminating section are integrally formed as shown in FIG. The coating unit includes a gravure plate 17, a doctor 19, an offset roller 15C, an impression roller / laminating roller 11, and another laminating roller 16. The relationship between the rotation direction of the gravure plate and the rotation direction of the offset roller may be either forward or reverse. In the case of the reverse direction shown in FIG. 3, the gravure plate from which the doctor 19 has scraped off the excess adhesive is rotated in the reverse direction (reverse rotation) of the offset roller 15C, and the cells of the gravure plate are spread and flattened. And transfer to an offset roller, which is advantageous in appearance.

The rotation direction of the impression roller and the offset roller is preferably a forward rotation, and it is preferable that the (rotation ratio of the impression roller / offset roller) is slightly smaller than 1 from the viewpoint of smoothing the coated surface.

The laminating section 20 comprises a heated impression roller / laminating roller 11 and a laminating roller 16. And it is preferable that the contact point of both rollers is as close as possible to the offset roller 15C so that it can be laminated with the bonding film immediately after the application of the adhesive. The heater 18 heats the adhesive side on the film side of the laminating section by warm air, infrared rays, high frequency, or the like, similarly to the one shown in FIG. 1 or FIG.

In particular, although not shown, the base film used in the laminate of the present invention may be subjected to a corona discharge treatment, a flame treatment, or a plasma treatment immediately before the application of the adhesive. Further, it is preferable to heat the base film and / or the bonding film immediately before laminating.

According to the laminate of the present invention, wetting of the adhesive and the film is improved and the film can be made uniform, so that the pressing time at the time of lamination can be shortened. It is possible to prevent a defect phenomenon such as tunneling that easily occurs in laminating. Then, it effectively acts on the instant curing of an adhesive composed of a non-solamid ionizing radiation-curable resin whose adhesive strength tends to decrease when the processing speed is increased.

[0030]

EXAMPLES Examples will be described below in more detail. (Example) As a base film 1, a stretched polypropylene film having a thickness of 20 μm and subjected to a single-sided corona discharge treatment,
An unstretched polypropylene film having a thickness of 20 μm and subjected to a one-sided corona discharge treatment as a bonding film 2 and an acrylic electron beam-curable non-sol adhesive AD- as an adhesive 4
5 (trade name, manufactured by Kansai Paint Co., Ltd.). Using a four-roller laminating machine shown in FIG.
Feed rollers 13, 14 and coating roller 1
2 at 70 ° C. and the impression roller 11
Then, the base film is pressed against the coating roller,
g / m ² of the adhesive is applied to the treated surface of the base film 1 at the processing speeds of 30, 100 and 150 m / min shown in Table 1, and the treated surface of the laminated film 2 is laminated in the laminating section. The roller 16 and the impression roller / laminate roller 11 were in close contact with each other at the laminating section 20. Immediately after the contact, although not shown, the electron beam is applied to the same line at a voltage of 1
Irradiation was carried out under the conditions of 80 KeV and a dose of 3 Mrad to cure the adhesive, and composite films 3 of Examples 1 to 3 were produced.

(Comparative Example) Using the same material as in Example 1 and using a conventional four-roller laminating machine shown in FIG. 4, an adhesive coating portion 21 and a laminating portion 20 were separated by about 1 m. Except for the adhesive temperature, feed rollers 13, 14,
Coating roller 12, impression roller 11
Then, the laminating roller 16 is heated to 70 ° C., the coating amount of the adhesive is 2 g / m ² , and the processing speed is 3 as in the embodiment.
Example 1 set to 0, 100 and 150 m / min
Under the same conditions as in Example 3, composite films 3 of Comparative Examples 1 to 3 were prepared.

Table 1 shows the results of the following tests performed on each sample of the examples and comparative examples 24 hours after processing. -Adhesive strength: The composite film was cut at a width of 15 mm in the processing direction, peeled accurately in a T shape under a peeling condition of 50 mm / min, and the strength was measured. -Foaming state: The presence or absence of foaming was visually evaluated for the composite film.

[0033]

[Table 1]

[0034]

As described above, according to the present invention, the impression roller and the laminating roller are provided for both the coating section and the laminating section, and the heating adhesive layer immediately after being coated on the base film is bonded to the bonding layer. Adhere to film. Therefore, stronger adhesive strength can be obtained even in low-speed processing, and even if high-speed processing is performed conventionally, there is no problem that the adhesive is well drained, and there is no trouble such as white clouding due to foaming and a decrease in adhesive strength. The adhesive for non-solami used only for low-speed processing of about 30 m / min is also 100 m.
/ Min, and an effect that can be applied to high-speed machining at 150 m / min.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a composite apparatus having an impression roller and a laminating roller according to the present invention.

FIG. 2 is a schematic cross-sectional view of another composite measure having an impression roller and a laminating roller of the present invention.

FIG. 3 is a schematic sectional view of a composite device using a gravure plate having an impression roller and a laminating roller according to the present invention.

FIG. 4 is a schematic sectional view of a conventional laminating machine having a coating section and a laminating section.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base film 2 Laminating film 3 Composite film 4 Adhesive 11 Impression roller and laminating roller 11P impression roller 12 Coating roller 13, 14 Feed roller 15, 15C Offset roller 16 Laminating roller 17 Gravure plate 18 Heater 19 Doctor 20 Laminating part 21 Coating department

Claims (4)

[Claims] In a production of a composite film processed with an adhesive composed of a non-volatile component, an impression roller for applying the adhesive to a base film includes a laminating unit for pressing the base film and the bonding film. A film composite device that is also used as a roller. 2. A bonding film, comprising heating the adhesive feed roller and the coating roller using the film composite apparatus according to claim 1, and applying the heated adhesive to the base film. And a method for producing a composite film. 3. A method of heating an offset roller, a coating roller, an impression roller, and a laminating roller portion for transferring an adhesive from a feed roller, continuously heating the adhesive, and bonding the base film and the bonding film. The method for producing a composite film according to claim 1, wherein: 4. The method for producing a composite film according to claim 1, wherein an adhesive made of an ionizing radiation-curable resin is used as the adhesive.