JPH0132268B2 - - Google Patents

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to paper, plastic sheet, plastic film coated with an adhesive, or a combination thereof (hereinafter collectively referred to as a base sheet). A long or single-fed adhesive made by laminating paper, plastic sheet, or plastic film coated with a release agent, or a combination of these sheets (hereinafter collectively referred to as release sheet) to The present invention relates to a method and apparatus for manufacturing a sheet, and particularly to a method for manufacturing a so-called non-curl adhesive sheet that does not curl, and an apparatus therefor.

[Prior art]

Adhesive sheets are generally constructed by laminating two types of materials with different characteristics. That is, a base sheet coated with an adhesive and a release sheet coated with a release agent are bonded together, and the base sheet and the release sheet are often made of different materials.
Such pressure-sensitive adhesive sheets often curl after a certain period of time has passed after being manufactured. When the adhesive sheet curls, it becomes a hindrance to post-processing, such as printing on the surface of the base sheet or cutting.

This curling phenomenon is caused by the bimetallic effect that occurs when two sheets of different materials are adhesively laminated together under different conditions such as temperature and humidity, or by changes in tension, curling, or a combination of these. It occurs when multiple effects work.

Conventionally, methods to prevent curling include making two types of materials that are pasted the same in terms of temperature, humidity, etc. characteristics, or making the materials difficult to change due to temperature, humidity, etc. It was getting worse. Alternatively, damping, cooling, tension control, etc., were extremely strictly controlled during the coating process.

However, the above-mentioned method is not a sufficient solution because it is accompanied by an increase in cost and it is often impossible to make the characteristics of two types of materials the same with respect to temperature, humidity, etc.

As a method other than the above, a method may be used in which a curling process is applied to the curled adhesive sheet using a roller or other member to remove the curl. However, this "styling" cannot completely remove curls.

[Problem that the invention seeks to solve]

The present invention aims to eliminate the drawbacks of conventional curl removal methods and provide a method for producing a non-curl adhesive sheet that quickly and completely removes curls at a relatively low cost, as well as an apparatus therefor. .

[Means for solving problems]

A pressure-sensitive adhesive sheet completed by a conventional method, that is, a pressure-sensitive adhesive sheet in which a base sheet coated with an adhesive and a release sheet coated with a release agent are laminated together, is fed to a peeling device that peels the base sheet and the release sheet. , by first peeling off both sheets, then feeding both sheets to a bonding device and bonding them together again, or in some cases cutting immediately after that, a non-curling long or single sheet that does not cause curling can be produced. We succeeded in obtaining an adhesive sheet.

[Action of the invention]

By once removing the adhesive between the adhesive on the base sheet and the release agent on the release sheet, the anchoring effect due to the solid content in the adhesive is reduced, resulting in a situation where curling occurs after they are reattached. It is thought that in some cases, the base sheet and the release sheet slip, although only slightly, and curl does not occur. Furthermore, there is also the effect of eliminating the internal stress by once removing the strain caused by the internal stress, and as a result, the strain (curl) can be removed. the result,
Again, it is possible to prevent any curling from occurring even if environmental changes in temperature and humidity are applied, and even if it does occur, it is possible to ensure that the curling is only to the extent that it is practically no problem. When the non-curl pressure-sensitive adhesive sheet subjected to the method of the present invention is used after the release sheet is removed, the adhesive strength of the pressure-sensitive adhesive tends to decrease, although only slightly, compared to the pressure-sensitive adhesive sheet that is not subjected to the process. However, it is not so great that it impairs practicality. The benefits of curl removal are far more valuable.

〔Example〕

Example 1 As shown in FIG. 1, a rolled adhesive sheet 1 is loaded into a feeding device 4, and the rolled adhesive sheet 1 fed out from the feeding device is moved to a base sheet or a release sheet by an oscillating roll 5 that moves up and down. 2 and the release sheet or base sheet 3 are continuously peeled off, and the separated sheets 2 and 3 are then guided to a re-bonding device 8 consisting of pressure rolls 6, 7, etc. and bonded together, and the curls of the bonded sheets 2 and 3 are removed. The removed non-curl adhesive sheet 9 is obtained. The non-curl adhesive sheet 9 can also be cut into sheets 11 of a required size by a cutting device 10, if necessary.

Note that whether the swinging roll 5 is made to act on the base sheet or on the release sheet may be determined as appropriate depending on the curl situation. Alternatively, it may be performed for both sheets. Depending on the magnitude and strength of the oscillation, the tension can be controlled and curl removal can be made more effective.

Example 2 FIG. 2 shows a process diagram when the adhesive sheet to be imparted with non-curl properties is a single sheet, and shows a feeding process A in which sheets are fed out one by one from a stack of sheets, and a supplied sheet adhesive sheet. Peeling step B in which the sheet 12 is peeled into the base sheet 13 and the release sheet 14 by the peeling roll 15; both sheets 13 once peeled;
14 by re-bonding pressure rolls 16 and 17, and a cutting step D in which the adhesive sheets are cut into smaller adhesive sheets if necessary.

Example 3 The process equipment shown in FIG. 1 as Example 1 is connected to the rear part of a normal pressure-sensitive adhesive sheet manufacturing machine. However, this is an in-line method for producing a non-curl adhesive sheet, which omits the usual adhesive sheet winding section and omits the sheet feeding device shown in FIG.

Embodiment 4 FIG. 3 shows another embodiment, in which a sheet winding device 18 is provided in place of the cutting machine 10 in the first embodiment (FIG. 1). According to this embodiment,
The processing speed can be greatly improved compared to the case of the first embodiment. The processing speed can be increased to approximately three times or more compared to the first embodiment.

The non-curl adhesive sheet 9 manufactured according to this embodiment is wound into a roll by a winding device 18, and then cut into sheets by a high-speed cutter, for example a rotary cutter, installed separately. Note that it is desirable to cut the rolled non-curl adhesive sheet as quickly as possible.

Example 5 Guillotine type cutting machine 1 of Example 1 (Fig. 1)
A high-speed rotary cutting machine (not shown) is used instead of the cutting machine. However, in this case, the cutting accuracy is inferior to that in the first embodiment.

Example 6 A combination of Example 1 and Example 4, in which a non-curl adhesive sheet winding device 18 is provided after the bonding device 8, and a cutting machine 10 or a rotary type cutting machine is provided after that. When using the sheet winding device 18, a guide means is provided to guide the sheet through the sheet winding device 18 to the cutting machine 10 without operating the sheet winding device 18.
According to this example, it is convenient because either the winding device or the cutting machine can be selected and used depending on the material of the adhesive sheet or the required processing speed. Note that the positions of the sheet winding device 18 and the cutting machine 10 may be reversed.

[Effects of the Invention] The present invention can be easily and quickly applied without taking any measures to change the characteristics of the base sheet and release sheet used in the adhesive sheet, and without placing particular restrictions on the materials used. This method is effective in completely removing curls at a relatively low cost.

In particular, claims 1 to 3 of the present invention
The non-curl adhesive sheet produced by the method or device described in 1. is capable of removing curls that occur during changes over time, environmental changes, special conditions during the production of adhesive sheets, etc., after such conditions have disappeared, or By once peeling off the adhesive sheets that have curled when various conditions are in equilibrium, the internal stress (strain) that causes each sheet to curl is released, and then the sheets can be reattached. It has the effect of preventing any or almost no subsequent curling.

Furthermore, when producing the non-curl pressure-sensitive adhesive sheet according to the invention described in claims 1 to 3, the tension for one of the sheets once peeled off is set to a different value from that for the other sheets. It can be added freely and imparting non-curl properties is extremely easy.

Furthermore, if the present invention is applied to a long adhesive sheet, the mismatch in length of both sheets due to curling can be reduced to the final necessary minimum loss of one sheet. be able to.

Furthermore, according to the present invention as set forth in claim 3, since sheets of the required size are formed immediately after re-bonding, it is possible to minimize the occurrence of curls that may occur thereafter. It is possible.

Furthermore, according to the invention set forth in claim 4, although it is somewhat inferior to the former in terms of curl removal, it is superior in terms of reducing the overall equipment cost and total cost.

All of the present inventions and embodiments have greater effects than conventional methods for removing curls, improve the yield rate of products, and greatly contribute to cost reduction.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram showing an example of the device of the present invention;
FIG. 2 is a process diagram showing another example, and FIG. 3 is a schematic explanatory diagram showing another example. In the figure, 1 is a rolled adhesive sheet, and 2 and 3 are base sheets or release sheets. 4 is a sheet feeding device, 5 is a rocking roll, 6 and 7 are pressure rolls, 8 is a bonding device, 9 is a non-curling adhesive sheet, 10 is a cutting device, 15 is a peeling roll, and 18 is a sheet winding device The devices are shown respectively.

Claims (1)

[Scope of Claims] 1. A non-curl adhesive characterized in that a pressure-sensitive adhesive sheet is prepared by laminating a release sheet to a base sheet coated with an adhesive, and the base sheet and the release sheet are peeled off and then both sheets are pasted together again. Method of manufacturing sheets. 2. Non-curling device consisting of a pressure-sensitive adhesive sheet feeding device in which a release sheet is bonded to a base sheet coated with an adhesive, a device for peeling off the base sheet and the release sheet, and a device for re-bonding the peeled base sheet and release sheet. Adhesive sheet manufacturing equipment. 3. A device for supplying a long adhesive sheet in which a release sheet is bonded to a base sheet coated with an adhesive, a device for peeling off the base sheet and the release sheet, a device for reattaching the peeled base sheet and the release sheet, and A non-curl adhesive sheet manufacturing device comprising a cutting device that immediately cuts a re-bonded long adhesive sheet sent out from a bonding device into single-fed adhesive sheets of required dimensions. 4 A step of applying an adhesive to a base sheet, a step of drying the adhesive as necessary, a step of laminating the base sheet and a release sheet coated with a release agent, and a step of drying the adhesive sheet that has been laminated. A method for producing a non-curl adhesive sheet, which comprises the steps of peeling off both sheets, re-attaching the peeled sheets, and cutting the re-attached adhesive sheet.