JPS6262735A - Manufacture of laminated film - Google Patents

Abstract

PURPOSE:To solve a trouble of air trapping without making holes in a cover film and without occurrence of cutting, deforming or meandering of the cover film, by placing an air-permeable sheet whose width is the same as the width of the web at least between an adhesive layer and the cover film and by starting lamination of the adhesive layer and the cover film. CONSTITUTION:An air-permeable sheet 9 adhered on a cover film 2 with an adhesive tape 8 is laminated on an adhesive layer 10 applied on a base film 1 by means of a laminate nip roller 3. Air, included between the adhesive layer 10 and a cover film 2 at the front part of the adhesive layer or at a jointed part of the cover film, is pushed by a pass roller while it is making a trouble of air trapping and enters into the air-permeable sheet 9 along the non-adhesive surface of the adhesive tape 8. The pass roller smashes the air-permeable sheet 9 and extrudes the air contained therein to the outside of both side surfaces of the air-permeable sheet 9 or the laminated surface along the shape of the back end by the ahesive strength of the adhesive.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing a laminate film, and in particular, when the adhesive layer applied on the base film web and the cover film have relatively low adhesive strength, - This relates to a method for manufacturing a laminate film that prevents air pocket failures that occur during lamination with Z-film.

[Prior art]

In dry lamination, where the adhesion is relatively weak, when the leading edge of the coating material is fed in, the coating material may be present in the thick areas due to air A or me between the base film and the cover film, as shown in Figure 9. As shown in Fig. 8, the air is squeezed by the nog roller 25 after the laminating nip roller, and the air squeezed by the roller surface pressure due to the base tension peels off the adhesive and Camo film, and forms the air as shown in 26. Causes stagnation.

The air accumulated in front of the E-slower gradually exceeds the A-slower, causing quality defects such as air pocket failure 27.

However, improvements have been made to the method of joining the new web to the old web and the method of separating the laminating nip roller. However, a satisfactory countermeasure could not be obtained, and since air entrainment in the web was unavoidable, a needle drum was used to make many small holes on the entire surface of the cover film just before lamination to let the entrained air escape and eliminate air pockets. Methods were taken to prevent failures from occurring. (For example, see Japanese Patent Application Laid-Open No. 57-61559.) [Problems to be Solved by the Invention] Method f, in which holes are made in the cover film and the laminated cut film using a device using a needle drum, has a low adhesive strength. Although it is possible to discharge a relatively large amount of staying air in the laminated film, it is difficult to completely discharge the small amount of staying air caused by distortion of the cover film around the hole when the hole is made. Since the adhesive force between the cover film and the adhesive layer is weak, air pockets between the cover film and the adhesive layer may cause failures.

In addition, for product quality reasons, for products that require a top coat to fill the needle hole, or for products that require a ζ-rear cover film, the needle hole can only be opened during startup when air can enter. An open area cannot be a product. Furthermore, the needle drum must be removed after the needle hole is punched. However, with the method using a circular needle drum, the
Since the needles were injected into the film, it was difficult to open the hole at the same speed as the cover film and immediately remove the needle drum.

An object of the present invention is to eliminate the above-mentioned drawbacks, and to solve the problem of air pockets without creating holes, cutting, deforming, meandering, etc. of the cover film. The purpose of the present invention is to provide a method for producing a laminate film suitable for low-tack adhesive films and products requiring ζ rear properties.

[Means for solving problems]

The present invention provides a method for producing a laminate film in which an adhesive is applied on a web of a film to form an adhesive layer, and the adhesive layer is continuously laminated with a cover film, at least the adhesive layer and the force/ζ film. This is a method for producing a laminate film, which comprises interposing an air permeable sheet having the same width as the web width between them, and then starting lamination of the adhesive layer and the Kakka film.

The invention will be explained with the aid of figures. FIG. 1 is a plan view of one embodiment of a laminate film on which the breathable sheet of the present invention is applied, FIG. 2 is a cross-sectional view of FIG. 1, and FIG. 3 is another embodiment of the laminate film of the present invention. FIG.

Figure 2 shows a cross section of a laminate film in which a cover film 2 is laminated with a breathable sheet 9 pasted with adhesive tape 8 on an adhesive layer 10 coated on a base film 1. A breathable sheet 9 is attached with an adhesive 81 in advance to the adhesive layer 10 applied above.
FIG. 2 is a cross-sectional view of a laminated film that has been applied and then laminated with a cut ζ-film 2.

4 and 5 are a plan view and a cross-sectional view, respectively, of the laminate film showing a state in which a part of the breathable sheet is laminated before the front end of the adhesive layer.

In the present invention, the angle θ between the Δ-shaped rear end of the breathable sheet and the width direction of the pace is preferably about 15 degrees, since if it is 10 degrees or less, the occurrence of air pocket failure can be prevented.

Further, the breathable sheet 9 in the present invention is made of cloth, gauze, resin film, etc. that is breathable in the width direction, and its thickness is 100 mm.
~200μ is suitable. If the thickness is thick, the △-shaped part 12
This is undesirable because air pockets occur in the laminating roller section, and if it is too thin, air permeability will be poor.

[For production]

In the present invention, air pocket failure 11 is caused by air entrainment that occurs when laminating the tip of the adhesive layer 10 applied on the base film 1 or the joint part of the cover film.
The air is pushed by the pass roller after lamination and enters the breathable sheet 9 along the laminated surface of the adhesive layer or cover film.The air permeable sheet 9 is compressed by the adhesive force of the pass roller and the adhesive material, and the air is The gas is discharged out of the laminate surface along both side end faces of the breathable sheet and the rear end △ shape.

〔Example〕

The method for applying a breathable sheet according to the present invention will be explained with reference to the drawings. Fig. 6 is a schematic diagram of an apparatus for laminating the air-permeable sheet of the present invention after it has been applied to the cover film side, and Fig. 7 is a schematic diagram of an apparatus for laminating the air-permeable sheet of the invention on the adhesive layer on the base film. It is an explanatory view of a cloth device.

In FIG. 6, before the adhesive layer 10 coated on the base film 1 and the cover film 2 are laminated, a nip drum 6 paired with a suction nip drum 5 is placed on the cover roller side. A breathable sheet pasting device is installed. A breathable sheet 9 having a width dimension equivalent to that of the base film 1, a length of 2 to 3 mfi, and a rectangular rear end is attached with an adhesive tape 8 to be used for attaching the cover film to the suction nip drum 5. is prepared on the suction surface 7 of. The suction nip drum 5 has its internal pressure reduced by an external suction source (not shown), and the suction surface 7 holds the tape 8 by suction.

Immediately after the tip of the adhesive layer applied to the base film 1 is laminated with the cover film 2 by the laminating nip roller 6 in the prepared state as described above, the cover film 2 with the breathable sheet 9 pasted thereon and the adhesive layer are laminated together. A signal is sent to the suction nip drum 5 so that the breathable sheet 9 can be laminated with the cover film 2, or immediately after the joint of the cover film 2 passes through the breathable sheet pasting device section, the breathable sheet 9 can be pasted onto the cover film 2. The nip drum rotates once at the same speed as the running speed of the cover film web, and the breathable sheet 9 is pasted onto the cover film 2 with adhesive tape 8. At this time, the suction nip drum 5 stops reducing the pressure and helps the adhesive tape 8 to be separated from the suction surface 7. After transferring the breathable sheet 9 to the cover film 2, the suction nip drum 5 and the nip drum 6 stop rotating. The breathable sheet 9 pasted on the cover film 2 is laminated with a laminating nip roller 6''I1% adhesive layer 10 as shown in FIG.

The leading edge of the adhesive layer or the cover film joint ↑ The air caught between the adhesive layer 10 and the cover film 2 is pushed by the pass roller 12 while creating an air pocket failure 11 and is pushed along the non-adhesive surface of the adhesive tape 8. The pass roller that enters the breathable sheet 9 crushes the breathable sheet 9 and discharges the contained air out of the laminate surface along the side edges of the breathable sheet 90 or along the C-shape of the rear end using the adhesive force of the adhesive material. become. This can prevent future air pocket failures.

FIG. 7 shows an embodiment of a device for pasting the breathable sheet 9 on the side of the adhesive layer 10 coated on the base film 1, and the symbols and functions in the figure are exactly the same as in FIG. 6. ,
The surface of the suction nip drum is treated with Teflon (registered trademark) to avoid adhesion to the adhesive layer. FIG. 6 shows a cross section of the laminate film in which the breathable sheet 9 is pasted on the adhesive layer 10 by a signal after the leading edge of the adhesive layer 10 has passed through the pasting device part. FIG. 5 shows a cross section of the laminate film with the signal 1 breathable sheet 9 pasted on the adhesive/810 just before passing through.

〔Effect of the invention〕

As explained above, by discharging the trapped air using the breathable sheet of the present invention, there is no need to make holes in the cover film, and there is no occurrence of cutting, deformation, meandering, etc. of the cover film. We were able to solve the air pocket problem. The adhesive strength between the adhesive layer and the cover film is low.
In particular, the present invention has further improved the quality and yield of products requiring barrier properties in the cover film.

[Brief explanation of drawings]

FIG. 1 is a plan view of one embodiment of a laminate film using a breathable sheet according to the present invention, FIG. 2 is a cross-sectional view of FIG. 1, and FIG. 6 is a plan view of a laminate film according to another embodiment of the present invention. 4 is a plan view of a laminate film using a breathable sheet across the tip of the adhesive layer of the present invention, FIG. 5 is a cross-sectional view of FIG. 4, and FIG. A schematic diagram of an apparatus for laminating the air-permeable sheet on the surface of the cover film, and FIG. 7 is an explanatory diagram of the application apparatus for applying the air-permeable sheet of the present invention onto the adhesive layer on the base film. Moreover, FIG. 8 is a schematic diagram explaining the generation of air pockets,
FIG. 9 is a cross-sectional view similar to FIG. 2 obtained by the conventional lamination method. 1...Base film, 2...Cover film, 6
... Laminating nip roller, 5... Suction nip drum, 6... Nip drum, 7... Adsorption surface,
8... Adhesive tape, 9... Breathable sheet, 10...
・Adhesive layer, 11...Air pocket failure.

Claims (1)

[Claims] In a method for manufacturing a laminate film, the adhesive material is applied onto a web of a base film to form an adhesive layer, and a cover film web is continuously laminated to the adhesive layer, at least between the adhesive layer and the front cover film. A method for producing a laminate film, comprising: interposing a breathable sheet having the same width as the web width, and then starting lamination of the adhesive layer and the cover film.