JP2014069295A - Method for cutting resin films - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for cutting resin films, in which generation of cracks, chips, and the like can be remarkably reduced.SOLUTION: A method for cutting a resin film in which the resin film is cut with a cutting blade is provided, the method comprising a cutting step for conducting the cutting of the resin film in a state in which an auxiliary film is placed on a position where the cutting is planned to be conducted, the position being on the surface of the cutting blade side of the resin film. An elongation rate, in compliance with JIS K 7127(1999), of the auxiliary film is higher than that of the resin film.

Description

  The present invention relates to a method for cutting a resin film.

  Many of the transparent polymer films used for optical applications are generally obtained by casting a dope on a support using a casting die, peeling the dope from the support, and then stretching or drying the dope. The obtained film is cut into a predetermined size by a pair of upper and lower cutting blades. In this cutting process, if the film has poor cutting properties, cracks may occur on the cut surface, and chips and chips may be generated. It adheres to the film and causes coating defects when processing such as coating is performed on the cut film. Moreover, when cutting property is bad, the film may be cut at a portion other than the cutting portion. Therefore, when cutting the film, it is important to suppress the generation of cracks and the generation of chips and chips as much as possible.

  Under such circumstances, for example, in Patent Document 1, in order to improve the cutting performance, for example, the cutting portion of the polymer film is locally heated to a temperature of Tg (glass transition temperature) to Tg + 100 ° C. A method of cutting has been proposed. Patent Document 2 also proposes a method of cutting in a state where the residual volatile content of the film at the time of cutting and the temperature of the cut portion of the film are maintained within a predetermined range. According to these proposals, the effect of suppressing the generation of cracks on the cut surface and the generation of chips and chips can be expected.

Japanese Patent Laid-Open No. 01-281896 Japanese Patent Laid-Open No. 09-085680

  However, these conventional techniques require a heating device for the film and a utility device associated therewith, and thus require a large amount of capital investment. Further, it cannot be used for a film whose characteristics are deteriorated by heating.

  The present invention has been made in view of such circumstances, and a resin film that can prevent generation of cracks, chips, and chips when the resin film is cut without making a large investment in equipment and heating the film. The main problem is to provide a cutting method.

  The invention for solving the above-mentioned problems is a method for cutting a resin film by cutting a resin film with a cutting blade, wherein an auxiliary film is applied on the planned cutting position of the surface of the resin film on the cutting blade side. Including a cutting step of cutting the resin film in a state, wherein the auxiliary film has a higher tensile elongation in accordance with JIS K 7127 (1999) than the resin film.

  Further, the cutting blade is a pair of cutting blades composed of an upper blade and a lower blade, and the cutting step is intended to cut the surface on the upper blade side and / or the surface on the lower blade side of the resin film. It may be a step of cutting the resin film in a state where the auxiliary film is applied on the position.

It is a fragmentary sectional view for explaining one embodiment of the cutting method of the present invention. It is a fragmentary sectional view for explaining one embodiment of the cutting method of the present invention. It is a fragmentary sectional view for explaining one embodiment of the cutting method of the present invention.

  Hereinafter, the method for cutting a resin film of the present invention will be specifically described with reference to the drawings.

  The resin film cutting method of the present invention is a resin film cutting method for cutting the resin film 1 with the cutting blade 10 as shown in FIGS. A cutting step of cutting the resin film 1 in a state where the auxiliary film 2 is applied on the planned cutting position on the side surface is included. And this invention is characterized by the tensile elongation rate based on JISK7127 (1999) of the auxiliary | assistant film 2 being higher than the tensile elongation rate of the resin film 1. FIG.

  Hereinafter, an embodiment of the cutting method of the present invention will be described with reference to FIGS. FIG. 1 shows a cutting portion of a cutting apparatus for carrying out an embodiment of the present invention, which includes one cutting blade 10 and assists on a planned cutting position on the surface of the resin film 1 on the cutting blade 10 side. A film 2 is provided. 2 and 3 show a cutting portion of a cutting apparatus for carrying out an embodiment of the present invention, and are provided with a pair of cutting blades composed of an upper blade 10a and a lower blade 10b. In FIG. 2, the auxiliary film 2 is provided on the planned cutting position on the surface on the upper blade 10 a side of the resin film 1, and in FIG. 3, the auxiliary film 2 is disposed on the planned cutting position on the surface on the lower blade 10 b side of the resin film 1. Is provided.

  As shown in FIG. 1 to FIG. 3, the resin film 1 that is an object to be cut has a cutting blade in a state in which the auxiliary film is applied on the planned cutting position of the surface of the resin film 1 on the cutting blade side. It is conveyed to the cutting part 11 and cut. Hereinafter, what the auxiliary film is applied to the cutting position on the surface of the resin film 1 on the cutting blade 10 side is simply referred to as “sheet 3”.

  In the present invention, while the sheet 3 is being conveyed, the sheet 3 may be continuously cut in the conveying direction, or the sheet 3 may be intermittently cut in the width direction. The cutting unit 11 shown in FIG. 1 has a single cutting blade 10 and is configured to cut the sheet 3 by moving the cutting blade 10 in the thickness direction of the sheet 3. Moreover, the cutting part 11 shown by FIG. 2, FIG. 3 is the structure which cut | disconnects the sheet | seat 3 by moving the upper blade 10a toward the thickness direction of the sheet | seat 3, in other words, the lower blade 10b which is a fixed blade. Take. The cutting portion 11 of the present invention is not limited to this configuration. For example, in the configuration shown in FIGS. 2 and 3, both the upper blade 10 a and the lower blade 10 b are moved in the direction in which the sheet 3 is sandwiched. The sheet 3 may be cut off. In addition to this, the sheet 3 may be cut by rotating either one of the cutting blades or both of the cutting blades with the sheet 3 held between the pair of upper and lower cutting blades. That is, there is no limitation in particular about the cutting part 11, A conventionally well-known thing can be selected suitably, and can be used.

  In the form shown in FIG. 1, only one cutting part 11 is shown, but a plurality of cutting parts 11 may be provided according to the cutting width of the sheet 3.

<Resin film>
There is no limitation in particular about the resin film cut | disconnected by the cutting method of this invention, A conventionally well-known resin film can be selected suitably and can be used. Examples thereof include resin films mainly composed of triacetyl cellulose (TAC), polyethylene terephthalate (PET), polyethylene naphthalate, polybutylene terephthalate, polybutylene naphthalate, polyarylate, polytetramethylene terephthalate, and the like. . The resin film may be a mixture of two or more kinds of resins.

  There is no limitation in particular also about the shape of a resin film, A web-like resin film may be sufficient and a sheet-like resin film may be sufficient.

  The thickness of the resin film is not particularly limited, but is usually about 20 μm to 500 μm.

<Auxiliary film>
As shown in FIGS. 1 to 3, the auxiliary film applied on the planned cutting position of the surface of the resin film 1 on the cutting blade 10 side is a tensile elongation rate based on JIS K 7127 (1999) rather than the resin film. Is an essential condition.

  The auxiliary film satisfying this condition is scheduled to be cut on the cutting blade side of the resin film 1, for example, the cutting blade 10 side in FIG. 1, the upper blade 10a side in FIG. 2, and the lower blade 10b side in FIG. By cutting the resin film 1 in a state applied to the position, it is possible to prevent the resin film from being cracked, and to reduce the generation of chips and chips.

  A clear mechanism for achieving the above effect by cutting the auxiliary film 2 satisfying the above condition by the cutting part 11 in a state where the auxiliary film 2 is placed on the planned cutting position of the resin film 1 is not necessarily clear at present. In the cutting method of the invention, the auxiliary film 2 having a higher tensile elongation in accordance with JIS K 7127 (1999) than the resin film is applied to the position to be cut by the cutting portion 11 of the resin film 1. Since the resin film 1 is cut, the stress applied to the resin film 1 by the cutting portion 11 can be absorbed by the auxiliary film 2 at the time of cutting. And by making the auxiliary | assistant film 2 absorb the stress concerning the resin film 1 by the cutting part 11, generation | occurrence | production of the crack which arises in the resin film 1 which is a cutting | disconnection object, and generation | occurrence | production of chips and chips are prevented. Inferred.

  On the other hand, in a state where the auxiliary film 2 having a high tensile elongation according to JIS K 7127 (1999) is not applied on the planned cutting position of the resin film 1 or on the planned cutting position of the resin film 1 When the cutting by the cutting part 11 is performed in a state where the auxiliary film 2 having a lower tensile elongation rate according to JIS K 7127 (1999) than the film 1 is applied, in the former, all of the stress by the cutting part 11 is In the latter case, the stress applied to the resin film 1 cannot be sufficiently absorbed by the cutting portion 11 in the latter case. Therefore, in any of the above cases, the excellent effect cannot be obtained as in the cutting method of the present invention.

  The auxiliary film 2 only needs to satisfy the condition that the tensile elongation rate according to JIS K 7127 (1999) is higher than that of the resin film 1. It may be selected as appropriate in consideration. For example, when a triacetyl cellulose (TAC) film is used as the resin film, polyethylene terephthalate (PET) having a higher tensile elongation according to JIS K 7127 (1999) than the triacetyl cellulose (TAC) film as the auxiliary film. ) A film or the like may be used.

  In the case where the cutting part 11 is configured to include a pair of cutting blades of the upper blade 10a and the lower blade 10b, the auxiliary film 2 has a planned cutting position on the surface on the upper blade 10a side of the resin film 1 as shown in FIG. It may be applied only to the upper side, as shown in FIG. 3, may be applied only to the planned cutting position on the surface of the lower blade 10b side of the resin film 1, and on the planned cutting positions on both surfaces. May be assigned to each (not shown).

  For example, as shown in FIGS. 1 and 2, in the cutting unit 11 that performs cutting by moving only the upper blade 10 a, the auxiliary film 2 is applied on the planned cutting position on the surface of the cutting blade 10 and the upper blade 10 a side. When the cutting is performed in the state, the stress by the cutting blade 10 and the upper blade 10a can be absorbed by the auxiliary film 2. On the other hand, as shown in FIG. 3, when the auxiliary film 2 is applied on the planned cutting position of the surface on the lower blade 10 b side, when the upper blade 10 a moves, the space between the lower blade 10 b and the resin film 1 is The auxiliary film 2 applied on the planned cutting position on the lower blade 10b side absorbs the stress applied to the lower blade 10b, and as a result, the stress applied to the resin film 1 during cutting can be relaxed. Therefore, the cutting unit 11 including one cutting blade 10 includes a pair of cutting blades formed on the planned cutting position of the surface on the one cutting blade side and the upper blade 10a and the lower blade 10b. When cutting by the part 11, by applying the auxiliary film 2 to any one surface of the resin film 1, the stress applied to the resin film 1 can be alleviated and the generation of cracks, chips, etc. can be prevented. Can do.

  2 and 3, that is, when the cutting portion 11 is composed of the upper blade 10 a and the lower blade 10 b and only the upper blade 10 a is movable, the stress applied to the resin film 1 by the cutting portion 11 is The surface on the upper blade 10a side of the resin film 1 is higher. Therefore, in this case, it is preferable that the auxiliary film 2 is applied on the planned cutting position on the surface on the upper blade 10a side of the resin film 1, and the auxiliary film 2 is applied on the planned cutting position on both surfaces. It is particularly preferred that

  At the time of cutting, the resin film 1 and the auxiliary film 2 are cut so as to be pressed by the cutting portion 11, and therefore, at the time of cutting, the resin film 1 and the auxiliary film 2 are in close contact with each other at the cutting location. Therefore, the resin film 1 and the auxiliary film 2 do not need to be in close contact before cutting. That is, the auxiliary film 2 only needs to be superimposed on the resin film 1, but the auxiliary film 2 is displaced when the sheet 3 is cut by the cutting unit 11 depending on the size of the auxiliary film 2 and the planned cutting position. In some cases, the auxiliary film 2 may be wrinkled, or the auxiliary film 2 may be displaced from the planned cutting position. If this point is taken into consideration, before cutting, the resin film 1 and the auxiliary film 2 are adhered to each other with a certain degree of adhesion, specifically, such that the auxiliary film is not wrinkled or displaced at the time of cutting. It may be. The adhesion between the resin film 1 and the auxiliary film 2 can be easily realized by, for example, bonding the resin film 1 and the auxiliary film 2 through electrostatic adhesion or a peelable adhesive.

  In addition, normally, at the time of the cutting | disconnection by the cutting part 11, the resin film 1 is cut | disconnected in the state fixed by the predetermined fixing member 20, as shown in FIGS. 1-3. For example, when the web-shaped resin film 1 is cut, the web-shaped resin film 1 is cut in a state where portions other than the planned cutting position are fixed by a fixing member 20 or the like provided on the conveyance path of the web-shaped resin film 1. Further, the sheet-like resin film 1 is cut in a state where the vicinity of each of the opposing sides is fixed by a fixing member. Therefore, for example, by using an auxiliary film that is approximately the same size as the resin film 1 and using a sheet that is superposed on substantially the entire surface of the resin film 1, a planned cutting position on one or both surfaces of the resin film 1. In addition, the auxiliary film 2 can be reliably applied without causing wrinkles or misalignment. Moreover, you may apply the auxiliary | assistant film 2 to a strip | belt shape only in the cutting plan position by the cutting part 11, and its vicinity.

  The cutting method of the present invention has been described above. However, the cutting method of the present invention can take various modifications without departing from the spirit of the present invention.

  Hereinafter, the present invention will be specifically described with reference to examples and comparative examples.

Example 1
Prepare a sheet in which a polyethylene terephthalate (PET) film with a thickness of 38 μm is superimposed as an auxiliary film on the entire surface of a triacetyl cellulose (TAC) film with a thickness of 60 μm, and convey it at a predetermined position while conveying it at a line speed of 30 m / min. The sheet was cut by a cutting device that cuts the sheet by moving the upper blade shown in FIG.

(Comparative Example 1)
The triacetyl cellulose (TAC) film was cut in the same manner as in Example 1 except that the auxiliary film was not superposed.

(Crack evaluation)
The presence or absence of occurrence of cracks in the triacetylcellulose (TAC) film cut by Example 1 and Comparative Example 1 was visually confirmed. The evaluation results are shown in Table 1. In the table, ◯ means that the occurrence of cracks could not be confirmed, and x means that the occurrence of cracks could be confirmed.

(Chip evaluation)
The presence or absence of generation of chips in the triacetyl cellulose (TAC) film cut by Example 1 and Comparative Example 1 was visually confirmed. The evaluation results are shown in Table 1. In addition, (circle) in a table | surface means that generation | occurrence | production of the chip which can be confirmed visually was not able to be confirmed, and x means that the chip could be confirmed visually.

DESCRIPTION OF SYMBOLS 1 ... Resin film 2 ... Auxiliary film 3 ... Sheet 10 ... Cutting blade 10a ... Upper blade 10b ... Lower blade 11 ... Cutting part 20 ... Fixing member

Claims (2)

A resin film cutting method for cutting a resin film with a cutting blade,
On the planned cutting position of the surface of the cutting edge side of the resin film, including a cutting step of cutting the resin film in a state where an auxiliary film is applied,
The auxiliary film has a tensile elongation percentage based on JIS K 7127 (1999) higher than that of the resin film. The cutting blade is a pair of cutting blades composed of an upper blade and a lower blade,
The cutting step is a step of cutting the resin film in a state in which the auxiliary film is applied on a planned cutting position of the surface on the upper blade side and / or the surface on the lower blade side of the resin film. The cutting method of the resin film of Claim 1 characterized by these.

Images