Long strip membrane

Abstract

The present invention relates to a strip film having multiple knurled portions, wherein the planar shape of the knurled portions, when viewed from the thickness direction of the strip film, includes a first line group portion and a second line group portion. The first line group portion and the second line group portion include multiple straight portions and corner portions. The corner portions have an angle of 80° to 100° independently, and the positions of the corner portions are different in the width direction of the strip film.

Description

Technical Field

[0001] This invention relates to a strip film with a knurled portion. Background Technology

[0002] In the past, from the viewpoint of achieving high productivity, films such as optical films have been manufactured into long strips. However, since the films are usually thin, their processability is sometimes poor. Therefore, it has been proposed to form irregularities at the ends of the film in the width direction to improve the processability of the film (Patent Document 1).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent document 1: International Publication No. 2017 / 145718. Summary of the Invention

[0006] The problem the invention aims to solve

[0007] In typical manufacturing, long strips of film are continuously transported along their length and subjected to various processes before being wound into rolls for shipment. Typically, when long strips of film are wound into rolls, air gaps are formed between the overlapping strips. Thus, in the areas where these air gaps exist, the overlapping strips of film do not come into contact with each other.

[0008] When the air layer is thin, the strips of film may come into contact and adhere to each other surface by surface. This phenomenon of surface adhesion of strips of film overlapping in a roll is sometimes called "blocking." For example, rolls are sometimes stored with their axis horizontal. In this case, the roll's own weight generates axial compressive stress within the roll. When this stress causes deformation of the roll's shape, creating localized areas with thin air layers, blocking may occur in those areas.

[0009] Furthermore, when the aforementioned stress, which causes axial compression, is generated on the roll, buckling sometimes occurs on the circumferential surface of the roll as the stress increases. "Buckling" of the roll refers to a concave portion formed by the roll partially denting in the radial direction. This buckling tends to occur in the thicker portions of the air layer between the overlapping, wound strips of film. Moreover, in the portions where buckling occurs, the strips of film sometimes deform, forming wrinkles.

[0010] The property of suppressing adhesion and wrinkling as described above is sometimes referred to as the "wrapability" of a strip film. While forming irregularities like those in Patent Document 1 on the film can improve the wrapability to some extent, further improvement in wrapability is required.

[0011] The present invention was made in view of the above-mentioned problems, and its object is to provide a long strip film with excellent winding properties.

[0012] Solution for solving the problem

[0013] In order to solve the above-mentioned problems, the inventors conducted in-depth research and discovered that the above-mentioned problems could be solved by the following elongated film, thus completing the present invention. That is, the present invention includes the following contents.

[0014] [1] A strip film having a plurality of knurled portions formed by continuous linear protrusions and recesses on at least one side, wherein,

[0015] Viewed from the thickness direction of the aforementioned elongated film, the planar shape of the knurled portion includes a first thread group portion and a second thread group portion.

[0016] The aforementioned first-line assembly includes:

[0017] The first straight section extends in a straight line from the first position to the first corner.

[0018] The second straight section extends in a straight line from the first corner to the second corner.

[0019] The third straight section extends in a straight line from the second corner to the third corner.

[0020] The fourth straight section extends in a straight line from the third corner to the fourth corner.

[0021] The fifth straight section extends in a straight line from the fourth corner to the fifth corner.

[0022] The sixth straight section extends in a straight line from the fifth corner to the sixth corner.

[0023] The seventh straight section extends in a straight line from the sixth corner to the seventh corner, and...

[0024] The eighth straight section extends in a straight line from the aforementioned seventh corner to the second position.

[0025] The aforementioned second line assembly includes:

[0026] The ninth straight section extends in a straight line from the third position to the eighth corner.

[0027] The tenth straight section extends in a straight line from the eighth corner to the ninth corner.

[0028] The eleventh straight section extends in a straight line from the ninth corner to the tenth corner.

[0029] The twelfth straight section extends in a straight line from the aforementioned tenth corner to the eleventh corner.

[0030] The thirteenth straight section extends in a straight line from the eleventh to the twelfth corner.

[0031] The fourteenth straight section extends in a straight line from the twelfth to the tenth triangular section.

[0032] The fifteenth straight section extends in a straight line from the aforementioned tenth triangular section to the fourteenth triangular section, and...

[0033] The sixteenth straight section extends in a straight line from the fourteenth corner to the fourth position.

[0034] The first to fourteenth corners mentioned above each have an angle of 80° to 100° independently.

[0035] The positions of the corners differ along the width of the elongated membrane.

[0036] [2] According to the long strip film described in [1], the deviation of the interval between the corners in the width direction of the long strip film is less than 1.00 mm.

[0037] [3] According to the elongated film described in [1] or [2], when a first virtual straight line passing through the first position and the second position is drawn with a line three times thicker than the width of the aforementioned uneven portion, the second corner portion, the fourth corner portion, and the sixth corner portion are located on the first virtual straight line.

[0038] When a second virtual straight line is drawn through the third and fourth positions using a line that is three times thicker than the width of the aforementioned concave and convex portions, the ninth corner, the eleventh corner, and the tenth triangle are located on the aforementioned second virtual straight line.

[0039] [4] According to any one of [1] to [3], in the case where a first virtual circle with a diameter of a first virtual line segment connecting the first position and the second corner is drawn using a line three times thicker than the width of the aforementioned uneven portion, the first corner is located on the aforementioned first virtual circle.

[0040] When a second virtual circle is drawn with a diameter equal to three times the width of the aforementioned uneven portion, and the second virtual line segment connecting the aforementioned second corner portion and the aforementioned fourth corner portion is used as the diameter, the aforementioned third corner portion is located on the aforementioned second virtual circle.

[0041] When a third virtual circle is drawn with a diameter equal to three times the width of the aforementioned uneven portion, and the third virtual line segment connecting the aforementioned fourth corner portion and the aforementioned sixth corner portion is used as the diameter, the aforementioned fifth corner portion is located on the aforementioned third virtual circle.

[0042] When a fourth virtual circle is drawn with a diameter equal to three times the width of the aforementioned uneven portion, and the fourth virtual line segment connecting the aforementioned sixth corner portion and the aforementioned second position is used as the diameter, the aforementioned seventh corner portion is located on the aforementioned fourth virtual circle.

[0043] When a fifth virtual circle is drawn with a diameter equal to three times the width of the aforementioned uneven portion, and the fifth virtual line segment connecting the aforementioned third position and the aforementioned ninth corner portion is used as the diameter, the aforementioned eighth corner portion is located on the aforementioned fifth virtual circle.

[0044] When a sixth virtual circle is drawn with a diameter equal to three times the width of the aforementioned uneven portion, and the sixth virtual line segment connecting the aforementioned ninth corner portion and the aforementioned eleventh corner portion is used as the diameter, the aforementioned tenth corner portion is located on the aforementioned sixth virtual circle.

[0045] When a seventh virtual circle is drawn with a diameter equal to the seventh virtual line segment connecting the eleventh corner and the tenth triangle, using a line three times thicker than the width of the aforementioned concave and convex portions, the twelfth corner is situated on the aforementioned seventh virtual circle.

[0046] When an eighth virtual circle is drawn with a diameter equal to the eighth virtual line segment connecting the tenth triangular part and the fourth position, using a line three times thicker than the width of the aforementioned concave and convex portions, the fourteenth triangular part is located on the aforementioned eighth virtual circle.

[0047] [5] According to the elongated membrane described in [4], the diameters of the first virtual circle to the eighth virtual circle are equal.

[0048] [6] The elongated film according to any one of [1] to [5], wherein the first thread group portion and the second thread group portion do not intersect.

[0049] [7] The elongated film according to any one of [1] to [6], wherein the elongated film has a substrate layer formed of a cyclic olefin resin or a (meth)acrylic resin.

[0050] Invention Effects

[0051] According to the present invention, a long strip film with excellent winding properties can be provided. Attached Figure Description

[0052] Figure 1 This is a schematic top view showing the appearance of the elongated film as viewed from the thickness direction of one embodiment of the present invention.

[0053] Figure 2 This is a schematic top view showing the planar shape of one of the knurled portions of the elongated film as viewed from the thickness direction of an embodiment of the present invention.

[0054] Figure 3 This is a schematic top view showing the planar shape of one of the knurled portions of the elongated film as viewed from the thickness direction of an embodiment of the present invention.

[0055] Figure 4This is a schematic top view showing the planar shape of one of the knurled portions of the elongated film as viewed from the thickness direction of an embodiment of the present invention.

[0056] Figure 5 This is a top view that enlarges and schematically shows an example of the first corner of the knurled portion of a strip film according to an embodiment of the present invention.

[0057] Figure 6 This is a schematic top view showing the planar shape of one of the knurled portions of the elongated film as viewed from the thickness direction of an embodiment of the present invention.

[0058] Figure 7 This is a schematic top view showing the planar shape of one of the knurled portions of the elongated film as viewed from the thickness direction of an embodiment of the present invention.

[0059] Figure 8 It is a top view schematically showing how the irradiation point P of a laser used to irradiate a corner moves.

[0060] Figure 9 It is a top view schematically showing the movement of the irradiation point P of a laser used to irradiate a certain straight section.

[0061] Figure 10 This is a schematic top view showing the planar shape of one of the knurled portions of the elongated film as viewed from the thickness direction of an embodiment of the present invention.

[0062] Figure 11 This is a schematic top view showing the planar shape of one of the knurled portions of the elongated film as viewed from the thickness direction of an embodiment of the present invention.

[0063] Figure 12 This is a schematic cross-sectional view showing a linear irregularity or irregularity included in the knurling portion of a strip film according to an embodiment of the present invention, cut with a plane perpendicular to the extending direction of the irregularity or irregularity.

[0064] Figure 13 This is a schematic top view showing the planar shape of one of the knurled portions of the elongated film as viewed from the thickness direction of the elongated film according to another embodiment of the invention.

[0065] Figure 14 This is a schematic top view showing the planar shape of one of the knurled portions of the elongated film as viewed from the thickness direction of the elongated film according to another embodiment of the invention.

[0066] Figure 15This is a schematic top view showing the planar shape of one of the knurled portions of the elongated film as viewed from the thickness direction of the elongated film according to another embodiment of the invention.

[0067] Figure 16 It is a top view that enlarges and schematically shows the first and second straight sections included in the knurling.

[0068] Figure 17 It is a top view that enlarges and schematically shows the first and second straight sections included in the knurling.

[0069] Figure 18 This is a top view schematically showing an example of the planar shape of the knurled portion of an embodiment of the present invention, viewed from the thickness direction of the elongated film.

[0070] Figure 19 This is a top view schematically showing another example of the planar shape of the knurled portion of an embodiment of the present invention, viewed from the thickness direction of the elongated film.

[0071] Figure 20 This is a schematic top view showing the planar shape of the knurled portion formed in Embodiment 1 of the present invention.

[0072] Figure 21 This is a schematic top view showing the planar shape of the knurled portion formed in Embodiment 1 of the present invention.

[0073] Figure 22 This is a schematic top view showing the planar shape of the knurled portion formed in Embodiment 2 of the present invention.

[0074] Figure 23 This is a schematic top view showing the planar shape of the knurled portion formed in Embodiment 2 of the present invention.

[0075] Figure 24 This is a schematic top view showing the planar shape of the knurled part formed in Comparative Example 1. Detailed Implementation

[0076] The present invention will be described in detail below with examples and embodiments shown. However, the present invention is not limited to the examples and embodiments shown below, and can be implemented by any modifications without departing from the scope of the claims and their equivalents.

[0077] In the following description, "strip" film refers to a film having a length that is 5 times or more than its width, preferably 10 times or more, specifically a length that allows it to be rolled up for storage or transport. There is no particular upper limit to the length of the strip film; for example, it can be up to 100,000 times its width.

[0078] In the following description, unless otherwise stated, the planar shape of the knurled portion formed on the film refers to the shape of the knurled portion as viewed from the thickness direction of the film.

[0079] In the following description, unless otherwise stated, "thickness direction" refers to the thickness direction of the film.

[0080] In the following description, unless otherwise specified, "(meth)acrylic acid" is a term that includes "acrylic acid", "methacrylic acid" and combinations thereof, and "(meth)acrylate" is a term that includes "acrylate", "methacrylate" and combinations thereof.

[0081] [1. Implementation method of long strip film]

[0082] Figure 1 This is a schematic top view showing the appearance of the elongated film 1 as viewed from the thickness direction of one embodiment of the present invention.

[0083] like Figure 1 As shown, the elongated film 1 is a long strip of film with a plurality of knurled portions 10 on at least one surface 1U. These plurality of knurled portions 10 are generally arranged in the length direction MD of the elongated film 1. Furthermore, the knurled portions 10 are generally provided at at least one end in the width direction TD of the elongated film 1, preferably at both ends. The planar shape of each knurled portion 10 may also be different when viewed from the thickness direction. In this embodiment, an example is shown in which all knurled portions 10 have the same planar shape.

[0084] Figure 2 This is a schematic top view showing the planar shape of one of the knurled portions 10 of the elongated film 1 as viewed from the thickness direction of an embodiment of the present invention. Figure 2 As shown, the knurled portion 10 is formed by continuous linear protrusions and depressions 20. These protrusions and depressions 20 can be formed by laser irradiation. Therefore, the protrusions and depressions 20, as the trajectory of the laser irradiation point, are generally formed as a continuous line in one stroke. Here, "in one stroke" means the shape of a line that is uninterrupted along the way. Moreover, the knurled portion 10 has a specific planar shape depicted by such linear protrusions and depressions 20.

[0085] Specifically, the planar shape of the knurled portion 10, viewed from the thickness direction of the elongated film 1, includes a first thread group portion 100 and a second thread group portion 200. The planar shape of the knurled portion 10, viewed from the thickness direction, may further include arbitrary portions in combination with the first thread group portion 100 and the second thread group portion 200. In this embodiment, an example is shown and described where the planar shape of the knurled portion 10, viewed from the thickness direction, includes a first connecting portion 300 and a second connecting portion 400 connecting the first thread group portion 100 and the second thread group portion 200.

[0086] Figure 3 This is a schematic top view showing the planar shape of one of the knurled portions 10 of the elongated film 1 as viewed from the thickness direction of the elongated film 1 according to one embodiment of the present invention. Wherein, in Figure 3 In the diagram, the first line group 100 is represented by a solid line, and the second line group 200, the first connecting part 300, and the second connecting part 400 are represented by dashed lines.

[0087] like Figure 3 As shown, the first line group 100 includes a first straight line section 111, a second straight line section 112, a third straight line section 113, a fourth straight line section 114, a fifth straight line section 115, a sixth straight line section 116, a seventh straight line section 117, and an eighth straight line section 118.

[0088] The first straight section 111 extends in a straight line from the first position 121 to the first corner 131. Therefore, the first straight section 111 can be a straight line segment having the first position 121 at one end and the first corner 131 at the other end. The first position 121 is a position on the first line group 100, typically the end of the first line group 100. The first corner 131 is a connecting portion linking the first straight section 111 and the second straight section 112. This first corner 131 can correspond to the vertex of the angle formed between the first straight section 111 and the second straight section 112. Therefore, the first corner 131 has an angle θ corresponding to the direction in which the first straight section 111 extends and the direction in which the second straight section 112 extends. 131 .

[0089] The second straight section 112 extends in a straight line from the first corner section 131 to the second corner section 132. Therefore, the second straight section 112 can be a straight line segment having a first corner section 131 at one end and a second corner section 132 at the other end. The second corner section 132 is a connecting portion linking the second straight section 112 and the third straight section 113. This second corner section 132 can correspond to the vertex of the angle formed between the second straight section 112 and the third straight section 113. Therefore, the second corner section 132 has an angle θ corresponding to the direction in which the second straight section 112 extends and the direction in which the third straight section 113 extends. 132 .

[0090] The third straight section 113 extends in a straight line from the second corner section 132 to the third corner section 133. Therefore, the third straight section 113 can be a straight line segment having a second corner section 132 at one end and a third corner section 133 at the other end. The third corner section 133 is the connecting portion linking the third straight section 113 and the fourth straight section 114. This third corner section 133 can correspond to the vertex of the angle formed between the third straight section 113 and the fourth straight section 114. Therefore, the third corner section 133 has an angle θ corresponding to the direction in which the third straight section 113 extends and the direction in which the fourth straight section 114 extends. 133 .

[0091] The fourth straight section 114 extends in a straight line from the third corner section 133 to the fourth corner section 134. Therefore, the fourth straight section 114 can be a straight line segment having a third corner section 133 at one end and a fourth corner section 134 at the other end. The fourth corner section 134 is a connecting portion linking the fourth straight section 114 and the fifth straight section 115. This fourth corner section 134 can correspond to the vertex of the angle formed between the fourth straight section 114 and the fifth straight section 115. Therefore, the fourth corner section 134 has an angle θ corresponding to the direction in which the fourth straight section 114 extends and the direction in which the fifth straight section 115 extends. 134 .

[0092] The fifth straight section 115 extends in a straight line from the fourth corner section 134 to the fifth corner section 135. Therefore, the fifth straight section 115 can be a straight line segment having a fourth corner section 134 at one end and a fifth corner section 135 at the other end. The fifth corner section 135 is the connecting portion linking the fifth straight section 115 and the sixth straight section 116. This fifth corner section 135 can correspond to the vertex of the angle formed between the fifth straight section 115 and the sixth straight section 116. Therefore, the fifth corner section 135 has an angle θ corresponding to the direction in which the fifth straight section 115 extends and the direction in which the sixth straight section 116 extends. 135 .

[0093] The sixth straight section 116 extends in a straight line from the fifth corner section 135 to the sixth corner section 136. Therefore, the sixth straight section 116 can be a straight line segment having a fifth corner section 135 at one end and a sixth corner section 136 at the other end. The sixth corner section 136 is the connecting portion linking the sixth straight section 116 and the seventh straight section 117. This sixth corner section 136 can correspond to the vertex of the angle formed between the sixth straight section 116 and the seventh straight section 117. Therefore, the sixth corner section 136 has an angle θ corresponding to the direction in which the sixth straight section 116 extends and the direction in which the seventh straight section 117 extends. 136 .

[0094] The seventh straight section 117 extends in a straight line from the sixth corner section 136 to the seventh corner section 137. Therefore, the seventh straight section 117 can be a straight line segment having a sixth corner section 136 at one end and a seventh corner section 137 at the other end. The seventh corner section 137 is the connecting portion linking the seventh straight section 117 and the eighth straight section 118. This seventh corner section 137 can correspond to the vertex of the angle formed between the seventh straight section 117 and the eighth straight section 118. Therefore, the seventh corner section 137 has an angle θ corresponding to the direction in which the seventh straight section 117 extends and the direction in which the eighth straight section 118 extends. 137 .

[0095] The eighth straight section 118 extends in a straight line from the seventh corner section 137 to the second position 122. Therefore, the eighth straight section 118 can be a straight line segment with a seventh corner section 137 at one end and a second position 122 at the other end. The second position 122 is a position on the first line group section 100, or it can be an end of the first line group section 100.

[0096] Figure 4 This is a schematic top view showing the planar shape of one of the knurled portions 10 of the elongated film 1 as viewed from the thickness direction of the elongated film 1 according to one embodiment of the present invention. Wherein, in Figure 4 In the diagram, the second line group 200 is represented by a solid line, and the first line group 100, the first connecting part 300, and the second connecting part 400 are represented by dashed lines.

[0097] like Figure 4 As shown, the second line group 200 includes a ninth straight line section 211, a tenth straight line section 212, an eleventh straight line section 213, a twelfth straight line section 214, a thirteenth straight line section 215, a fourteenth straight line section 216, a fifteenth straight line section 217, and a sixteenth straight line section 218.

[0098] The ninth straight section 211 extends in a straight line from the third position 221 to the eighth corner section 231. Therefore, the ninth straight section 211 can be a straight line segment having a third position 221 at one end and an eighth corner section 231 at the other end. The third position 221 is a position on the second line group section 200, typically one end of the second line group section 200. The eighth corner section 231 is a connecting portion linking the ninth straight section 211 and the tenth straight section 212. This eighth corner section 231 can correspond to the vertex of the angle formed between the ninth straight section 211 and the tenth straight section 212. Therefore, the eighth corner section 231 has an angle θ corresponding to the direction in which the ninth straight section 211 extends and the direction in which the tenth straight section 212 extends. 231 .

[0099] The tenth straight section 212 extends in a straight line from the eighth corner section 231 to the ninth corner section 232. Therefore, the tenth straight section 212 can be a straight line segment having an eighth corner section 231 at one end and a ninth corner section 232 at the other end. The ninth corner section 232 is the connecting portion linking the tenth straight section 212 and the eleventh straight section 213. This ninth corner section 232 can correspond to the vertex of the angle formed between the tenth straight section 212 and the eleventh straight section 213. Therefore, the ninth corner section 232 has an angle θ corresponding to the direction in which the tenth straight section 212 extends and the direction in which the eleventh straight section 213 extends. 232 .

[0100] The eleventh straight section 213 extends in a straight line from the ninth corner section 232 to the tenth corner section 233. Therefore, the eleventh straight section 213 can be a straight line segment having a ninth corner section 232 at one end and a tenth corner section 233 at the other end. The tenth corner section 233 is the connecting portion linking the eleventh straight section 213 and the twelfth straight section 214. This tenth corner section 233 can correspond to the vertex of the angle formed between the eleventh straight section 213 and the twelfth straight section 214. Therefore, the tenth corner section 233 has an angle θ corresponding to the direction in which the eleventh straight section 213 extends and the direction in which the twelfth straight section 214 extends. 233 .

[0101] The twelfth straight section 214 extends in a straight line from the tenth corner section 233 to the eleventh corner section 234. Therefore, the twelfth straight section 214 can be a straight line segment having a tenth corner section 233 at one end and an eleventh corner section 234 at the other end. The eleventh corner section 234 is the connecting portion linking the twelfth straight section 214 and the thirteenth straight section 215. This eleventh corner section 234 can correspond to the vertex of the angle formed between the twelfth straight section 214 and the thirteenth straight section 215. Therefore, the eleventh corner section 234 has an angle θ corresponding to the direction in which the twelfth straight section 214 extends and the direction in which the thirteenth straight section 215 extends. 234 .

[0102] The thirteenth straight section 215 extends in a straight line from the eleventh corner section 234 to the twelfth corner section 235. Therefore, the thirteenth straight section 215 can be a straight line segment having an eleventh corner section 234 at one end and a twelfth corner section 235 at the other end. The twelfth corner section 235 is the connecting portion linking the thirteenth straight section 215 and the fourteenth straight section 216. This twelfth corner section 235 can correspond to the vertex of the angle formed between the thirteenth straight section 215 and the fourteenth straight section 216. Therefore, the twelfth corner section 235 has an angle θ corresponding to the direction in which the thirteenth straight section 215 extends and the direction in which the fourteenth straight section 216 extends. 235 .

[0103] The fourteenth straight section 216 extends in a straight line from the twelfth angle section 235 to the tenth triangle section 236. Therefore, the fourteenth straight section 216 can be a straight line segment having the twelfth angle section 235 at one end and the tenth triangle section 236 at the other end. The tenth triangle section 236 is the connecting portion linking the fourteenth straight section 216 and the fifteenth straight section 217. This tenth triangle section 236 can correspond to the vertex of the angle formed between the fourteenth straight section 216 and the fifteenth straight section 217. Therefore, the tenth triangle section 236 has an angle θ corresponding to the direction in which the fourteenth straight section 216 extends and the direction in which the fifteenth straight section 217 extends. 236 .

[0104] The fifteenth straight section 217 extends in a straight line from the tenth triangular section 236 to the fourteenth angle section 237. Therefore, the fifteenth straight section 217 can be a straight line segment having the tenth triangular section 236 at one end and the fourteenth angle section 237 at the other end. The fourteenth angle section 237 is the connecting portion linking the fifteenth straight section 217 and the sixteenth straight section 218. This fourteenth angle section 237 can correspond to the vertex of the angle formed between the fifteenth straight section 217 and the sixteenth straight section 218. Therefore, the fourteenth angle section 237 has an angle θ corresponding to the direction in which the fifteenth straight section 217 extends and the direction in which the sixteenth straight section 218 extends. 237 .

[0105] The sixteenth straight section 218 extends in a straight line from the fourteenth corner section 237 to the fourth position 222. Therefore, the sixteenth straight section 218 can be a straight line segment with the fourteenth corner section 237 at one end and the fourth position 222 at the other end. The fourth position 222 is a position on the second line group section 200, or it can be one end of the second line group section 200.

[0106] Angle θ of the first corner 131 131 The angle θ of the second corner 132 132 The angle θ of the third corner 133 133 The angle θ of the fourth corner 134 134 The fifth angle θ is 135 degrees. 135 The angle θ of the sixth angle part is 136 degrees. 136 The angle θ of the seventh corner 137 137 The angle θ of the eighth corner 231 231 The angle θ of the ninth corner 232 232 The angle θ of the tenth corner 233 233 The angle θ of the eleventh corner 234 234 The twelfth angle θ is 235 degrees. 235 The angle θ of the tenth triangular part 236 236 and the angle θ of the fourteenth corner 237.237 Each angle is independently located within a specific angular range. This specific angular range is typically 80° or higher, preferably 85° or higher, more preferably 88° or higher, and generally below 100°, preferably below 95°, more preferably below 92°. Of these, 90° is particularly preferred. The angles θ from the first to the fourteenth angles 131-137 and 231-237 are... 131 ~θ 137 θ 231 ~θ 237 They can be the same or different.

[0107] In this specification, unless otherwise specified, "angle of a corner" refers to the angle at which the two straight lines connecting the corner intersect (0° ≤ angle of the corner ≤ 180°). A corner appears sharp in macroscopic observation but can have rounded corners in microscopic observation. In cases where a corner has rounded corners, unless otherwise specified, the angle at which the two straight lines intersect in macroscopic observation intersect represents the angle of the corner.

[0108] Figure 5 This is a top view, enlarged and schematically showing an example of the first corner 131 of the knurled portion 10 of a strip film 1 according to an embodiment of the present invention. For example, like... Figure 5 As shown in the example, when the first corner 131 connecting the first straight section 111 and the second straight section 112 has a rounded corner, the two straight sections (i.e., the first straight section 111 and the second straight section 112) that intersect at the first corner 131 in macroscopic observation are extended, and the angle at which the extended lines 111a and 112a intersect represents the angle θ of the first corner 131. 131 .

[0109] When the first to fourteenth corner portions 131-137 and 231-237 have rounded corners, the radius of curvature R of these corner portions 131-137 and 231-237 is preferably controlled within a specific range. This radius of curvature R is preferably 0.0 mm to 0.5 mm, more preferably 0.0 mm to 0.2 mm, and particularly preferably 0.0 mm to 0.1 mm. Unless otherwise specified, Figure 5 As shown, the radius of curvature of the corner represents the radius of curvature R of the rounded portion of that corner.

[0110] The first line group 100 and the second line group 200, each having the planar shape described above, can be serrated line portions comprising a plurality of consecutive straight lines. Furthermore, the first line group 100 and the second line group 200 can have a plurality of corner portions at the vertices of the serrated corners. By including the first line group 100 and the second line group 200 having such planar shapes, the knurled portion 10 can include a plurality of corner portions at a high density (number of corner portions per unit area).

[0111] Figure 6 This is a schematic top view showing the planar shape of one of the knurled portions 10 of the elongated film 1 as viewed from the thickness direction of the elongated film 1 according to one embodiment of the present invention. Wherein, in Figure 6 In the diagram, the first connecting part 300 and the second connecting part 400 are represented by solid lines, and the first line group part 100 and the second line group part 200 are represented by dashed lines.

[0112] like Figure 6 As shown, the planar shape of the knurled portion 10 of this embodiment, viewed from the thickness direction, can include: a first connecting portion 300 connecting the first position 121 of the first thread group portion 100 and the fourth position 222 of the second thread group portion 200; and a second connecting portion 400 connecting the second position 122 of the first thread group portion 100 and the third position 221 of the second thread group portion 200.

[0113] The shape of the first connecting portion 300 is not limited. From the viewpoint of shortening the forming time of the knurled portion 10 by forming the first connecting portion 300 in a short time, the first connecting portion 300 preferably includes straight line segments 311, 312 and 313.

[0114] The line segment 311, which connects to the first line group 100 at the first position 121, can extend parallel to or non-parallel to the first straight line 111 extending from the first position 121. When the line segment 311 extends non-parallel to the first straight line 111, an angle can be formed at the first position 121 connecting the first straight line 111 and the line segment 311. The angle θ of this angle... 121 Preferably at an angle θ with the first corner 131 131 The same specific angular range as the range of the first position 121. The angle θ of the angle that can be formed at the first position 121. 121 Angle θ with the first corner 131 131 They can be the same or different.

[0115] The line segment 313, which connects to the second line group 200 at the fourth position 222, can extend parallel to or non-parallel to the straight section (the sixteenth straight section 218 in this embodiment) within the second line group 200 extending from the fourth position 222. When the line segment 313 extends non-parallel to the straight section within the second line group 200 extending from the fourth position 222, a corner (not shown) can be formed at the fourth position 222 where the straight section and the line segment 313 connect. The angle θ of this corner... 222 (Not shown) Preferably at an angle θ with the first corner 131 131 The same specific angular range as the range of the fourth position 222. The angle θ that can be formed at the fourth position 222. 222 Angle θ with the first corner 131 131 They can be the same or different.

[0116] The first connecting portion 300 may also have corner portions 331 and 332 at the connecting portions of line segments 311, 312 and 313 included in the first connecting portion 300. The angle θ of the corner portions 311 and 312 included in the first connecting portion 300 331 and θ 332 Preferably, they are each independently located at an angle θ relative to the first corner 131. 131 The range is the same for a specific angle range. The angles θ of angles 331 and 332 are... 331 and θ 332 Angle θ with the first corner 131 131 They can be the same or different. Furthermore, the angle θ between corners 331 and 332... 331 and θ 332 They can be the same or different.

[0117] The shape of the second connecting portion 400 is not limited. From the viewpoint of shortening the forming time of the knurled portion 10 by forming the second connecting portion 400 in a short time, the second connecting portion 400 preferably includes straight line segments 411, 412 and 413.

[0118] The line segment 411, which connects to the first line group 100 at the second position 122, can extend parallel to or non-parallel to the straight section (the eighth straight section 118 in this embodiment) within the first line group 100 extending from the second position 122. When the line segment 411 extends non-parallel to the straight section within the first line group 100 extending from the second position 122, an angle (not shown) can be formed at the second position 122 connecting the straight section and the line segment 411. The angle θ of this angle... 122 (Not shown) Preferably at an angle θ with the first corner 131 131The same specific angular range as the range of the second position 122. The angle θ of the angle that can be formed at the second position 122. 122 Angle θ with the first corner 131 131 They can be the same or different.

[0119] The line segment 413, which connects to the second line group 200 at the third position 221, can extend parallel to or non-parallel to the ninth straight line 211 extending from the third position 221. When the line segment 413 extends non-parallel to the ninth straight line 211, an angle can be formed at the third position 221 connecting the ninth straight line 211 and the line segment 413. The angle θ of this angle... 221 Preferably at an angle θ with the first corner 131 131 The same specific angular range as the range of the third position 221. The angle θ of the angle that can be formed at the third position 221. 221 Angle θ with the first corner 131 131 They can be the same or different.

[0120] The second connecting portion 400 may also have corner portions 431 and 432 at the connecting portions of line segments 411, 412 and 413 included in the second connecting portion 400. The angle θ of the corner portions 431 and 432 included in the second connecting portion 400 is... 431 and θ 432 Preferably, they are each independently located at an angle θ relative to the first corner 131. 131 The range is the same for a specific angle range. The angles θ of angles 431 and 432 are... 431 and θ 432 Angle θ with the first corner 131 131 They can be the same or different. Furthermore, the angle θ between corners 431 and 432... 431 and θ 432 They can be the same or different.

[0121] Figure 7 This is a schematic top view showing the planar shape of one of the knurled portions 10 of the elongated film 1 as viewed from the thickness direction of an embodiment of the present invention. Figure 7 In order to easily grasp the position of the strip film 1 in the width direction TD, the shaft A extending in the width direction TD is shown together with the knurled part 10. TD .like Figure 7As shown, the positions of the first corner portion 131, the second corner portion 132, the third corner portion 133, the fourth corner portion 134, the fifth corner portion 135, the sixth corner portion 136, the seventh corner portion 137, the eighth corner portion 231, the ninth corner portion 232, the tenth corner portion 233, the eleventh corner portion 234, the twelfth corner portion 235, the tenth corner portion 236, and the fourteenth corner portion 237 are all different in the width direction TD of the strip film 1. When the first line group portion 100 and the second line group portion 200 have arbitrary corner portions (e.g., the corner portion at the first position 121, the corner portion at the third position 221, etc.) in addition to the first to fourteenth corner portions 131 to 137 and 231 to 237, it is preferable to include these arbitrary corner portions, and the positions of all the corner portions included in the first line group portion 100 and the second line group portion 200 are all different in the width direction TD. Furthermore, when the first connecting portion 300 and the second connecting portion 400 have corner portions 331, 332, 431 and 432, it is preferable to include these corner portions 331, 332, 431 and 432, and the positions of all the corner portions included in the knurled portion 10 are different in the width direction TD.

[0122] The elongated film 1 having the knurled portion 10 described above exhibits excellent winding properties. The inventors speculate on the mechanism by which such excellent winding properties are achieved. However, the scope of the present invention is not limited to the mechanism described below.

[0123] Figure 8 This is a top view schematically showing the movement of the irradiation point P of a laser used to illuminate a corner. Furthermore, Figure 9 This is a top view schematically showing the movement of the irradiation point P of a laser used to form a straight section. Figure 8 and Figure 9 In the diagram, the irradiation point P is shown moving in the directions indicated by arrows A1 and A2.

[0124] like Figure 8 and Figure 9 As shown, when the continuous linear unevenness 20 is formed, laser light is irradiated onto the film while the irradiation point P of the laser is moved. Figure 9 As shown, when a straight section is formed, the irradiation point P moves in a straight line. On the other hand, when a corner is formed, the irradiation point P moves in a turning manner at an appropriate angle. When the irradiation point P moves in a turning manner, the irradiation time of the laser becomes longer in the inner part of its moving direction, and therefore the energy density of the irradiated laser becomes greater. Therefore, at the corner, the height H of the concave-convex portion 20 (refer to...) Figure 12 (It gets higher.)

[0125] The knurled portion 10 in the above embodiment includes first to fourteenth corner portions 131-137 and 231-237, each having an angle θ close to 90°. 131~θ 137 θ 231 ~θ 237 According to the inventors' research, generally, the smaller the angle of a corner, the higher the corner can be. Therefore, an angle θ close to 90°... 131 ~θ 137 θ 231 ~θ 237 The first to fourteenth corner portions 131-137 and 231-237 can have a sufficiently large height. Furthermore, in the above embodiment, the angle θ of the first to fourteenth corner portions 131-137 and 231-237... 131 ~θ 137 θ 231 ~θ 237 All angles are close to 90°, exhibiting excellent uniformity. Therefore, the first to fourteenth corner sections 131–137 and 231–237 can possess a high and highly uniform height.

[0126] Furthermore, in the above embodiment, the first to fourteenth corner portions 131-137 and 231-237 are disposed at different positions on the width direction TD of the strip film 1. Therefore, the first to fourteenth corner portions 131-137 and 231-237 with high uniformity can be widely distributed in the knurled portion 10 on the width direction TD.

[0127] When the elongated film 1 is wound into a roll, each knurled portion 10 can support the elongated film 1. At this time, the first to fourteenth corner portions 131-137, 231-237 are in contact with another layer of elongated film 1 that is wound and overlapped. Since the first to fourteenth corner portions 131-137, 231-237 are high, the contact pressure of the above contact can be increased. Furthermore, since the height of the first to fourteenth corner portions 131-137, 231-237 is uniform and widely distributed in the knurled portions 10, the uniformity of the contact pressure can be improved. Therefore, the gripping force between the wound and overlapped elongated films 1 can be increased and made more uniform.

[0128] In this way, the aforementioned gripping force can overcome the stress applied to the roll (e.g., axial stress caused by the roll's own weight) with strong force and high uniformity. Therefore, the roll of the strip film 1 having the knurled portion 10 can suppress deformation caused by stress. Consequently, in this roll, the uniformity of the air layer thickness between the wound and overlapping strip films 1 can be improved. Therefore, since the formation of localized thin air layers can be suppressed, adhesion can be suppressed. Furthermore, since the formation of localized thick air layers can be suppressed, buckling and wrinkling can be suppressed. As described above, since adhesion and wrinkling can be effectively suppressed, the strip film 1 can achieve excellent winding performance.

[0129] However, as mentioned above, the smaller the angle of the corner, the higher the height of the corner can be. Therefore, it is also possible to consider making the angle of the corner an acute angle less than 90°. However, if an acute angle is formed, in order to form a ring-shaped knurled portion 10, it is required that the other corner be an obtuse angle greater than 90°. Therefore, the uniformity of the angle of the corner is reduced. In addition, the scanning distance of the laser used to form a knurled portion 10 (i.e., the distance the laser travels from the irradiation point P on the pre-processed film) becomes longer, and the time required to form a knurled portion 10 becomes longer, so the density of the knurled portion 10 (the number of knurled portions 10 per unit length) becomes smaller. Therefore, in the above case, the gripping force may become smaller, or the uniformity of the gripping force may become smaller. In contrast, in the above embodiment, by making the angles θ of the corners 131-137 and 231-237... 131 ~θ 137 θ 231 ~θ 237 Approximately 90°, the following balanced improvements were achieved: shortening the time required to form a knurled section 10, increasing the density of the knurled section 10, increasing the height of each corner section 131–137 and 231–237, and increasing the angle θ of the corner sections 131–137 and 231–237. 131 ~θ 137 θ 231 ~θ 237 The uniformity of the gripping force results in a large and highly uniform gripping force.

[0130] Furthermore, during the winding of the long strip film 1, the contact pressure at the first to fourteenth corner portions 131-137 and 231-237 can be increased, and the uniformity of the contact pressure can be improved. Therefore, the gripping force between the wound and overlapping long strip films 1 can generally be large and uniform. Thus, it is possible to suppress the deflection of the long strip film 1 in the width direction TD, or the tightening and loosening of the long strip film 1 in the length direction MD.

[0131] Furthermore, the first to fourteenth corner portions 131-137 and 231-237 can contact the transport roller (not shown) during the transport of the long strip film 1. At this time, the first to fourteenth corner portions 131-137 and 231-237 can contact the transport roller with a large and uniform contact pressure. Therefore, the gripping force (friction) of the long strip film 1 on the transport roller can generally be large and uniform, thus suppressing the lateral twisting of the long strip film 1 during transport and achieving high transportability.

[0132] As described above, the first to fourteenth corner portions 131 to 137 and 231 to 237 are disposed at different positions along the width direction TD of the elongated film 1. Therefore, as Figure 7As shown, in the width direction TD, a gap D is left between the first to fourteenth corner portions 131-137 and 231-237. This gap D represents the distance between two adjacent corner portions in the width direction TD of the long strip film 1. The range of this gap D is preferably 100 μm or more, more preferably 200 μm or more, particularly preferably 300 μm or more, preferably 3 mm or less, more preferably 2 mm or less, and particularly preferably 1 mm or less. When the gap D is within the above range, the winding properties of the long strip film 1 can be effectively improved, and it can also effectively suppress winding deviation, winding tightness, winding looseness, and left-right twisting. Furthermore, from the same point of view, it is preferable that the gap D in the width direction TD between all corner portions of the first thread group portion 100 and the second thread group portion 200, including any corner portion (e.g., the corner portion of the first position 121, the corner portion of the third position 221, etc.), is controlled within the above range. Furthermore, it is even more preferable that the spacing D in the width direction TD between all the knurled portions 10, including any corners (e.g., corners 331, 332, 431 and 432, etc.), is controlled within the above-mentioned range.

[0133] The spacing D may be non-uniform, but high uniformity is preferred. Therefore, the deviation of the spacing D between the first to fourteenth corner portions 131 to 137 and 231 to 237 in the width direction TD is preferably small. The deviation of the spacing D represents the difference between the maximum and minimum values ​​of the spacing D between the corner portions of a knurled portion 10. The deviation of the spacing D between the first to fourteenth corner portions 131 to 137 and 231 to 237 is preferably 0.00 mm to 1.00 mm, more preferably 0.00 mm to 0.50 mm, and particularly preferably 0.00 mm to 0.20 mm. When the deviation of the spacing D is within the above range, the winding properties of the strip film 1 can be effectively improved, and generally, winding deviation, winding tightness, winding looseness, and left-right twisting can also be effectively suppressed. Furthermore, from the same viewpoint, it is preferable that the deviation of the spacing D in the width direction TD between all corner portions of the first thread group portion 100 and the second thread group portion 200, including any corner portion (e.g., the corner portion of the first position 121, the corner portion of the third position 221, etc.), is controlled within the above range. Furthermore, it is even more preferable that the deviation of the width direction TD between all the knurled portions 10, including any corners (e.g., corners 331, 332, 431 and 432, etc.), is controlled within the above-mentioned range.

[0134] The first thread group 100 and the second thread group 200 included in the same knurled portion 10 preferably do not intersect. That is, the first thread group 100 and the second thread group 200 are preferably separated from each other by being formed at different positions. When the first thread group 100 and the second thread group 200 do not intersect, the distribution range of the first to fourteenth corner portions 131-137 and 231-237 can be expanded, thus effectively improving the winding properties of the long strip film 1, and generally also effectively suppressing winding deviation, winding tightness, winding looseness, and left-right twisting.

[0135] The first line group 100 and the second line group 200 included in the same knurled portion 10 are preferably formed at different positions along the length direction MD of the elongated film 1. In this case, the first line group 100 and the second line group 200 can be formed by irradiating the irradiation point P in a reciprocating manner. For example, the first line group 100 can be formed on the outward movement of the irradiation point P, and the second line group 200 can be formed on the return movement. Therefore, the irradiation start position and the irradiation end position of the laser forming the irregularities 20 of the knurled portion 10 can be made close in the width direction TD of the elongated film 1. Therefore, the adjustment amount of the optical system (such as the angle adjustment amount of the mirror, etc.) required for the laser to move the irradiation point P to form the next knurled portion 10 after forming one knurled portion 10 can be reduced. Therefore, the interval from forming one knurled portion 10 to forming the next knurled portion 10 can be shortened, and thus the density of the knurled portions 10 (the number of knurled portions 10 per unit length) can be increased.

[0136] Figure 10 This is a schematic top view showing the planar shape of one of the knurled portions 10 of the elongated film 1 as viewed from the thickness direction of the elongated film 1 according to one embodiment of the present invention. Wherein, in Figure 10 In the diagram, the first line group 100 is represented by a solid line, and the second line group 200, the first connecting part 300, and the second connecting part 400 are represented by dashed lines.

[0137] like Figure 10 As represented by a double-dotted line, imagine drawing a first virtual straight line 140 passing through the first position 121 and the second position 122 with a specific thickness. In this case, it is preferable that the second corner 132, the fourth corner 134, and the sixth corner 136 are located on the first virtual straight line 140. Unless otherwise specified, "corner located on virtual straight line" means that part or all of the corner's position coincides with the position of the virtual straight line. Furthermore, the thickness of the first virtual straight line 140 is preferably within the range of the width W of the concave and convex portions 20 (see reference). Figure 12 It is less than 3 times, more preferably less than 2 times, even more preferably less than 1.5 times, and more preferably more than 0.1 mm.

[0138] The aforementioned necessary condition for the first virtual straight line 140 indicates a high degree of regularity in the arrangement of the first position 121, the second position 122, the second corner 132, the fourth corner 134, and the sixth corner 136. Specifically, it means that the first position 121, the second position 122, the second corner 132, the fourth corner 134, and the sixth corner 136 can be located on a straight line represented by the first virtual straight line 140. However, even if there are errors in the positions of the first position 121, the second position 122, the second corner 132, the fourth corner 134, and the sixth corner 136, the desired effect can still be obtained. The preferred range of accuracy including this error is represented by the thickness of the first virtual straight line 140. Specifically, the thinner the first virtual straight line 140, the higher the accuracy (i.e., the smaller the error) that the first position 121, the second position 122, the second corner 132, the fourth corner 134, and the sixth corner 136 are located on a straight line.

[0139] When the knurled portion 10 has a planar shape of the first thread group portion 100 that satisfies the aforementioned necessary condition of the first virtual straight line 140, the winding properties of the long strip film 1 can be effectively improved, and it can also effectively suppress roll-off, roll-tightening, roll-loosening, and left-right twisting. In addition, the knurled portion 10 with a planar shape that satisfies this necessary condition can shorten the length of the uneven portion 20 used to form the knurled portion 10, so it can be formed in a short time.

[0140] Figure 11 This is a schematic top view showing the planar shape of one of the knurled portions 10 of the elongated film 1 as viewed from the thickness direction of the elongated film 1 according to one embodiment of the present invention. Wherein, in Figure 11 In the diagram, the second line group 200 is represented by a solid line, and the first line group 100, the first connecting part 300, and the second connecting part 400 are represented by dashed lines.

[0141] The second line group 200 is preferably the same as the first line group 100, satisfying the necessary conditions for a virtual straight line. Specifically, as follows: Figure 11 As represented by a double-dotted line, imagine drawing a second virtual line 240 passing through the third position 221 and the fourth position 222 with a specific width and thickness. In this case, it is preferable that the ninth corner 232, the eleventh corner 234, and the tenth corner 236 are located on the second virtual line 240. The range of the thickness of the second virtual line 240 can be the same as the range of the thickness of the first virtual line 140. Furthermore, the thickness of the first virtual line 140 and the thickness of the second virtual line 240 can be the same or different.

[0142] The necessary conditions for the second virtual line 240 are the same as those for the first virtual line 140, indicating a high degree of regularity in the arrangement of the third position 221, the fourth position 222, the ninth corner 232, the eleventh corner 234, and the tenth triangle 236. Specifically, this means that the third position 221, the fourth position 222, the ninth corner 232, the eleventh corner 234, and the tenth triangle 236 can lie on a straight line represented by the second virtual line 240 within a range of preferred precision indicated by the thickness of the second virtual line 240.

[0143] When the knurled portion 10 has a planar shape of the second thread group portion 200 that satisfies the aforementioned necessary condition of the second virtual straight line 240, the winding properties of the long strip film 1 can be effectively improved, and it can also effectively suppress roll-off, roll-tightening, roll-loosening, and left-right twisting. In addition, the knurled portion 10 with a planar shape that satisfies this necessary condition can shorten the length of the uneven portion 20 used to form the knurled portion 10, and can be formed in a short time.

[0144] like Figure 10 Imagine a first virtual line segment 141 connecting the first position 121 and the second corner 132, represented by a double-dotted line. Furthermore, as... Figure 10 As represented by a single-dot dashed line, imagine drawing a first virtual circle 151 with a diameter equal to the first virtual line segment 141 using a specific thickness. This first virtual circle 151 is relative to a circle with a diameter equal to the length of the first virtual line segment 141, centered at the midpoint of the first virtual line segment 141. In this case, it is preferable that the first corner 131 is located on the first virtual circle 151. Unless otherwise specified, "corner located on the virtual circle" means that part or all of the corner's position coincides with its position on the virtual circle (i.e., the position of the circumference drawn with the aforementioned specific thickness of line). Furthermore, the thickness range of the line of the first virtual circle 151 is preferably the width W of the concave-convex portion 20 (refer to...). Figure 12 It is less than 3 times, more preferably less than 2 times, even more preferably less than 1.5 times, and more preferably more than 0.1 mm.

[0145] The aforementioned necessary condition for the first virtual circle 151 indicates that the angle θ of the first corner 131 is such that... 131 It is close to a right angle. However, even at the angle θ of the first corner of 131°... 131 Even with errors, the desired effect can still be achieved. The preferred range of accuracy, including these errors, is represented by the thickness of the line of the first virtual circle 151. Specifically, the thinner the line of the first virtual circle 151, the more it represents the angle θ of the first corner 131. 131 The higher the precision, the closer it is to a right angle.

[0146] Furthermore, among the corners included in the first line group 100, the odd-numbered other corners counting from the first position 121 are preferably the same as the first corner 131, satisfying the above-mentioned necessary conditions for the virtual circle.

[0147] Specifically, such as Figure 10 Imagine a second virtual line segment 142 connecting the second corner 132 and the fourth corner 134, represented by a double-dotted line. Furthermore, as... Figure 10 As represented by a single-dot dashed line, imagine drawing a second virtual circle 152 with a diameter equal to the second virtual line segment 142 using a line of a specific thickness. In this case, it is preferable that the third corner 133 is located on the second virtual circle 152.

[0148] In addition, such as Figure 10 Imagine a third virtual line segment 143 connecting the fourth corner 134 and the sixth corner 136, represented by a double-dotted line. Furthermore, as... Figure 10 As represented by a single-dot dashed line, imagine drawing a third virtual circle 153 with a diameter equal to the third virtual line segment 143 using a line of a specific thickness. In this case, it is preferable that the fifth corner portion 135 is located on the third virtual circle 153.

[0149] In addition, such as Figure 10 Imagine a fourth virtual line segment 144 connecting the sixth corner 136 and the second position 122, represented by a double-dotted line. Furthermore, as... Figure 10 As represented by a single-dot dashed line, imagine drawing a fourth virtual circle 154 with a diameter of the fourth virtual line segment 144 using a line of a specific thickness. In this case, it is preferable that the seventh corner portion 137 is located on the fourth virtual circle 154.

[0150] The range of line thickness for the second virtual circle 152, the third virtual circle 153, and the fourth virtual circle 154 can each independently be the same as the range of line thickness for the first virtual circle 151. Furthermore, the line thicknesses of the first virtual circle 151, the second virtual circle 152, the third virtual circle 153, and the fourth virtual circle 154 can be the same or different.

[0151] When the knurled portion 10 has a planar shape of the first thread group portion 100 that satisfies the aforementioned necessary condition of a virtual circle, the winding properties of the elongated film 1 can be effectively improved, and it can also effectively suppress roll-off, roll-tightening, roll-loosening, and left-right twisting. In addition, the knurled portion 10 with a planar shape that satisfies this necessary condition can shorten the length of the uneven portion 20 used to form the knurled portion 10, so it can be formed in a short time.

[0152] The second line group 200 is preferably the same as the first line group 100, satisfying the necessary conditions for a virtual circle. That is, among the corners included in the second line group 200, the odd-numbered other corners counting from the third position 221 are preferably the same as the first corner 131, satisfying the necessary conditions for a virtual circle.

[0153] Specifically, such as Figure 11 Imagine a fifth virtual line segment 241 connecting the third corner 221 and the ninth corner 232, represented by a double-dotted line. Furthermore, as... Figure 11 As represented by a single-dot dashed line, imagine drawing a fifth virtual circle 251 with the fifth virtual line segment 241 as its diameter using a line of a specific thickness. In this case, it is preferable that the eighth corner portion 231 is located on the fifth virtual circle 251.

[0154] In addition, such as Figure 11 Imagine a sixth virtual line segment 242 connecting the ninth corner 232 and the eleventh corner 234, represented by a double-dotted line. Furthermore, as... Figure 11 As represented by a single-dot dashed line, imagine drawing a sixth virtual circle 252 with a diameter equal to the sixth virtual line segment 242 using a line of a specific thickness. In this case, it is preferable that the tenth corner portion 233 is located on the sixth virtual circle 252.

[0155] Furthermore, such as Figure 11 Imagine a seventh virtual line segment 243 connecting the eleventh triangle 234 and the tenth triangle 236, represented by a double-dotted line. Furthermore, as... Figure 11 As represented by a single-dot dashed line, imagine drawing a seventh virtual circle 253 with a diameter of the seventh virtual line segment 243 using a line of a specific thickness. In this case, it is preferable that the twelfth corner portion 235 is located on the seventh virtual circle 253.

[0156] In addition, such as Figure 11 Imagine an eighth virtual line segment 244 connecting the tenth triangle 236 and the fourth position 222, represented by a double-dotted line. Furthermore, as... Figure 11 As represented by a single-dot dashed line, imagine drawing an eighth virtual circle 254 with a diameter of the eighth virtual line segment 244 using a line of a specific thickness. In this case, it is preferable that the fourteenth corner portion 237 is located on the eighth virtual circle 254.

[0157] The range of line thickness for the fifth virtual circle 251, the sixth virtual circle 252, the seventh virtual circle 253, and the eighth virtual circle 254 can each independently be the same as the range of line thickness for the first virtual circle 151. Furthermore, the line thicknesses of the fifth virtual circle 251, the sixth virtual circle 252, the seventh virtual circle 253, and the eighth virtual circle 254 can be the same or different.

[0158] When the knurled portion 10 has a planar shape of the second thread group portion 200 that satisfies the aforementioned necessary condition of a virtual circle, the winding properties of the long strip film 1 can be effectively improved, and it can also effectively suppress roll-off, roll-tightening, roll-loosening, and left-right twisting. In addition, the knurled portion 10 with a planar shape that satisfies this necessary condition can shorten the length of the uneven portion 20 used to form the knurled portion 10, so it can be formed in a short time.

[0159] Furthermore, the diameters of the aforementioned virtual circles 151-154 and 251-254 are preferably equal. Therefore, the lengths of the first virtual segment 141, the second virtual segment 142, the third virtual segment 143, the fourth virtual segment 144, the fifth virtual segment 241, the sixth virtual segment 242, the seventh virtual segment 243, and the eighth virtual segment 244 are preferably equal. In this case, the winding properties of the long strip film 1 can be effectively improved, and it can generally effectively suppress roll deviation, tightness, looseness, and lateral twisting. Moreover, the knurled portion 10, having a planar shape that satisfies this necessary condition, can shorten the length of the irregular portions 20 used to form the knurled portion 10, thus enabling formation in a short time.

[0160] The planar shape of the knurled portion 10 is preferably an annular shape. In the above embodiment, the knurled portion 10 is made into an annular shape by continuously forming the first wire group portion 100, the second connecting portion 400, the second wire group portion 200, and the first connecting portion 300. When the knurled portion 10 with an annular shape is formed by laser in this way, the irradiation start position and irradiation end position of the laser used to form the uneven portion 20 of the knurled portion 10 can be set at the same position. Therefore, since the irradiation start position and irradiation end position can be aligned in the width direction TD of the strip film 1, the adjustment amount of the optical system (such as the angle adjustment amount of the mirror, etc.) that moves the irradiation point P of the laser used to form the next knurled portion 10 after forming one knurled portion 10 can be reduced. Therefore, since the interval from forming one knurled portion 10 to forming the next knurled portion 10 can be shortened, the density of the knurled portions 10 (the number of knurled portions 10 per unit length) can be increased.

[0161] like Figure 2 As shown, the length L of each knurled portion 10 on the width direction TD of the elongated film 1 is...TD The length L of each knurled portion 10 in the length direction MD of the elongated film 1 MD The ratio of L TD / L MD Preferably, it should be controlled within a specific range. Specifically, the above ratio L TD / L MD Preferably 2 or more, more preferably 2.5 or more, and particularly preferably 3 or more. In the ratio of L... TD / L MD When controlled within the above range, deformation can be suppressed and knurling 10 can be easily formed. The above ratio L TD / L MD There is no particular limit to the upper limit, but it is preferably 15 or less, more preferably 13 or less, and especially preferably 10 or less.

[0162] The length L of each knurled portion 10 on the length direction MD of the long strip film 1 is... MD Smaller is preferred. Specifically, the length L MD Preferably 20 mm or less, more preferably 15 mm or less, and particularly preferably 10 mm or less. In length L MD In smaller cases, the length of the irregular portions 20 used to form the knurled portion 10 can be shortened. Therefore, the knurled portion 10 can be formed in a shorter time. Furthermore, since the density of the knurled portions 10 along the length direction MD of the elongated film 1 can be increased, the winding properties of the elongated film 1 can be effectively improved, and issues such as roll deviation, tightness, looseness, and lateral twisting can generally be effectively suppressed. Length L MD There is no particular limitation on the lower limit, but it is preferably 0.1 mm or more, more preferably 0.5 mm or more, and particularly preferably 1 mm or more.

[0163] The length L of each knurled portion 10 in the width direction TD of the long strip film 1 TD Preferably, the ratio L is as described above. TD / L MD The method of controlling within the above range is appropriately set. Specifically, the length L of each knurled portion 10 on the width direction TD of the long strip film 1 is... TD Preferably, the thickness is 3mm or more, more preferably 5mm or more, especially preferably 7mm or more, preferably 20mm or less, more preferably 17mm or less, and especially preferably 15mm or less.

[0164] like Figure 1 As shown, the knurled portions 10 are typically arranged at specific intervals along the length direction MD of the strip film 1. In this case, the interval between the knurled portions 10 is preferably 0.5 mm or more, more preferably 1 mm or more, particularly preferably 1.5 mm or more, preferably 10 mm or less, more preferably 7 mm or less, and particularly preferably 5 mm or less. The interval between the knurled portions 10 can be fixed or varied.

[0165] Figure 12 This is a schematic cross-sectional view showing the linear irregularities 20 included in the knurled portion 10 of a strip film 1 according to an embodiment of the present invention, cut with a plane perpendicular to the extending direction of the irregularities 20.

[0166] like Figure 12 As shown, the irregular portion 20 forming the knurled portion 10 has a recess 21 and protrusions 22 provided on both sides of the recess 21. Generally, the recess 21 corresponds to the portion where resin has been removed by thermal melting or ablation using laser irradiation, while the protrusions 22 correspond to the portion where resin flows due to heating by the aforementioned laser irradiation. Since the protrusions 22 protrude more than the surface 1U of the surrounding strip film 1, the substantial thickness of the strip film 1 is increased in this irregular portion 20. As such, as described above, the winding properties of the strip film 1 can be improved.

[0167] The height H of the uneven portion 20 can be uniform or uneven. Typically, the height H of the uneven portion 20 differs between the corners and straight sections of the knurled portion 10. Furthermore, in the corners, the height H of the inner convex portion 22 and the outer convex portion 22 may differ.

[0168] The average height of the irregular and irregular portions 20 at the corners of the knurled portion 10 is preferably 1 μm or more, more preferably 2 μm or more, particularly preferably 3 μm or more, preferably 25 μm or less, more preferably 20 μm or less, and particularly preferably 15 μm or less. When the average height of the irregular and irregular portions 20 at the corners is at or above the lower limit of the above range, the winding properties of the elongated film 1 can be effectively improved, and it can also effectively suppress roll deviation, roll tightness, roll looseness, and lateral twisting. When the average height of the irregular and irregular portions 20 at the corners is at or below the upper limit of the above range, the winding diameter of the wound roll can differ between the portion where the knurled portion 10 is formed (e.g., the axial end of the roll) and the other portion (e.g., the axial center of the roll), thereby suppressing deformation of the elongated film 1.

[0169] The average height of the uneven portions 20 in the straight section of the knurled portion 10 is preferably 0.5 μm or more, more preferably 1 μm or more, particularly preferably 1.5 μm or more, preferably 25 μm or less, more preferably 20 μm or less, and particularly preferably 15 μm or less. When the average height of the uneven portions 20 in the straight section is at or above the lower limit of the above range, the winding properties of the strip film 1 can be effectively improved, and it can generally effectively suppress roll deviation, roll tightness, roll looseness, and left-right twisting. Furthermore, when the average height of the uneven portions 20 in the straight section is at or below the upper limit of the above range, deformation can be suppressed and the knurled portion 10 can be formed more easily.

[0170] The width W of the uneven portion 20 is preferably 0.1 μm or more, more preferably 0.15 μm or more, particularly preferably 0.2 μm or more, preferably 1 μm or less, more preferably 0.75 μm or less, and particularly preferably 0.5 μm or less. When the width W of the uneven portion 20 is at or above the lower limit of the above range, the winding properties of the strip film 1 can be effectively improved, and it can also effectively suppress roll deviation, roll tightness, roll looseness, and left-right twisting. Furthermore, when the width W of the uneven portion 20 in the straight section is at or below the upper limit of the above range, deformation can be suppressed and the knurled portion 10 can be easily formed.

[0171] The width and thickness of the elongated film 1 are not particularly limited, and can be selected according to the intended use. The width of the elongated film 1 is preferably 700 mm or more, more preferably 1000 mm or more, even more preferably 1200 mm or more, preferably 2500 mm or less, more preferably 2200 mm or less, and even more preferably 2000 mm or less. Furthermore, the thickness of the elongated film 1 is preferably 1 μm or more, more preferably 5 μm or more, even more preferably 20 μm or more, preferably 1000 μm or less, more preferably 300 μm or less, and even more preferably 150 μm or less.

[0172] When the elongated film 1 is used as an optical film, it is preferable that it has high transparency in the area without the knurled portion 10. Specifically, the total light transmittance of the elongated film 1 in the aforementioned area is preferably 85% to 100%, more preferably 92% to 100%. Furthermore, the haze of the elongated film 1 in the aforementioned area is preferably 0% to 5%, more preferably 0% to 3%, and particularly preferably 0% to 2%. The total light transmittance can be measured according to JIS K7105 using a "turbidity meter NDH-2000" manufactured by Nippon Denshoku Kogyo Co., Ltd. Furthermore, the haze can be measured using a "NDH2000" manufactured by Nippon Denshoku Kogyo Co., Ltd.

[0173] [2. Examples of deformation of elongated membranes]

[0174] The above describes a long strip film 1 according to one embodiment of the present invention, but the long strip film can be further modified. For example, in the above embodiment, the lengths of the straight sections 111 to 118 included in the first thread group 100 and the straight sections 211 to 218 included in the second thread group 200 are made uniform, or the lengths of these straight sections can be made non-uniform. Examples are shown below.

[0175] Figures 13-15 This is a schematic top view showing the planar shape of one of the knurled portions 30 of the elongated film as viewed from the thickness direction of the elongated film according to another embodiment of the present invention. Wherein, in Figure 14 and Figure 15In the diagram, the first connecting portion 700 and the second connecting portion 800 are indicated by dashed lines. Furthermore, in... Figure 15 In the diagram, double-dotted lines represent the first virtual line 140, the first virtual line segment 141, the second virtual line segment 142, the third virtual line segment 143, the fourth virtual line segment 144, the second virtual line 240, the fifth virtual line segment 241, the sixth virtual line segment 242, the seventh virtual line segment 243, and the eighth virtual line segment 244. Furthermore, in... Figure 15 In the diagram, the first virtual circle 151, the second virtual circle 152, the third virtual circle 153, the fourth virtual circle 154, the fifth virtual circle 251, the sixth virtual circle 252, the seventh virtual circle 253, and the eighth virtual circle 254 are represented by single-dot dashes.

[0176] like Figures 13-15 As shown, the planar shape of the knurled portion 30 includes a first thread group portion 500, a second thread group portion 600, a first connecting portion 700, and a second connecting portion 800.

[0177] The first line group 500 includes straight sections 511 to 518 of uneven lengths. However, the first line group 500 has the same planar shape as the first line group 100 described above. Specifically, the straight sections 511 to 518 of the first line group 500 each have a different length than adjacent straight sections (i.e., straight sections connected via corners). Figures 13-15 The following example is shown: the first straight section 511, the third straight section 513, the fifth straight section 515 and the seventh straight section 517 have the same length. In addition, the second straight section 512, the fourth straight section 514, the sixth straight section 516 and the eighth straight section 518 have the same length, but the lengths of the two groups are different.

[0178] The second line group 600 includes nine straight lines 611 to sixteenth straight lines 618 of uneven length. However, the second line group 600 has the same planar shape as the second line group 200 described above. Specifically, the straight lines 611 to 618 included in the second line group 600 each have a different length than adjacent straight lines (i.e., straight lines connected via corners). Figures 13-15 The following example is shown: the group of the ninth straight section 611, the eleventh straight section 613, the thirteenth straight section 615 and the fifteenth straight section 617 has the same length. In addition, the group of the tenth straight section 612, the twelfth straight section 614, the fourteenth straight section 616 and the sixteenth straight section 618 has the same length, but the lengths of the two groups are different.

[0179] Corresponding to the planar shapes of the first wire assembly portion 500 and the second wire assembly portion 600, the first connecting portion 700 and the second connecting portion 800 have planar shapes different from those of the first connecting portion 300 and the second connecting portion 400 in the above embodiments. The preferred necessary conditions required for these first connecting portions 700 and the second connecting portion 800 are the same as those for the first connecting portion 300 and the second connecting portion 400 in the above embodiments.

[0180] The knurled portion 30, including the first thread group portion 500 and the second thread group portion 600, can achieve the same effect as the knurled portion 10 described in the above embodiment. In addition, it has the advantage of being able to form the knurled portion 30 in a short time. Hereinafter, this advantage will be explained with reference to the accompanying drawings.

[0181] Figure 16 This is an enlarged and schematic top view showing the first straight section 111 and the second straight section 112 included in the knurled section 10. Furthermore, Figure 17 This is a top view that is enlarged and schematically shown, illustrating the first straight section 511 and the second straight section 512 included in the knurled portion 30. Figure 16 and Figure 17 In the diagram, for illustration purposes, the first virtual circle 151 is represented by a single-dot dashed line.

[0182] like Figure 16 and Figure 17 As shown, when the first corner 131 is 90°, the first corner 131 is located on the first virtual circle 151. Figure 16 As shown, when the diameters of the first virtual circles 151 are the same, the combined length of the first straight section 111 and the second straight section 112, which have the same length, is relatively long. On the other hand, as... Figure 17 As shown, the combined length of the first straight portion 511 and the second straight portion 512, which have different lengths, is relatively short. Therefore, compared to the first straight portion 111 and the second straight portion 112, which have the same length, the first straight portion 511 and the second straight portion 512, which have different lengths, can shorten the scanning distance of the laser used to form the uneven portion 20 (i.e., the distance the laser travels to the irradiation point P of the pre-processed film). The same applies to the straight portions other than the first straight portion 511 and the second straight portion 512. Therefore, the knurled portion 30, which includes the first line group portion 500 and the second line group portion 600, which have straight portions 511-518 and 611-618 with uneven lengths, can shorten the scanning distance of the laser required to form the knurled portion 30, and thus can be formed in a short time.

[0183] Specifically, among adjacent straight sections, the length L in the width direction TD of the relatively longer straight section... L The length L in the width direction of the relatively short straight portion S The ratio of LS / L L Preferably 1 / 3 or close to that. For example, in Figure 17 In the example shown, the length L in the width direction TD of the long second straight portion 512 L The length L of the short first straight portion 511 in the width direction TD S The ratio of L S / L L Preferably 1 / 3 or close to that. The above ratio L S / L L Preferably, it is 1 / 3.5 or more, more preferably 1 / 3.3 or more, particularly preferably 1 / 3.1 or more, preferably 1 / 2.5 or less, more preferably 1 / 2.7 or less, and particularly preferably 1 / 2.9 or less. In the ratio of L... S / L L Within the above range, it is easy to improve the uniformity of the interval D between the corners on the width direction TD of the long strip film.

[0184] The number of straight sections and corner sections in the first line group 100 is not limited to the above embodiment and can be further increased. Therefore, the first line group 100 may include more than 9 straight sections and more than 8 corner sections.

[0185] Furthermore, the number of straight sections and corner sections in the second line group 200 is not limited to the above embodiment and can be further increased. Therefore, the second line group 200 may include nine or more straight sections and eight or more corner sections.

[0186] As an example of increasing the number of straight and corner sections in this way, one can cite examples of having Figure 18 and Figure 19 The knurled portions 40 and 50 are shown in planar shape.

[0187] Furthermore, in the above embodiment, the first line group portion 100 and the second line group portion 200 have the same planar shape, but the first line group portion 100 and the second line group portion 200 may also have different planar shapes. Therefore, the number of straight sections in the first line group portion 100 may be the same as the number of straight sections in the second line group portion 200, or they may be different. Additionally, the number of corner sections in the first line group portion 100 may be the same as the number of corner sections in the second line group portion 200, or they may be different.

[0188] In the above embodiment, the knurled portion 10 includes a first connecting portion 300 and a second connecting portion 400, but the knurled portion may also not include a first connecting portion and a second connecting portion. Therefore, for example, the first position may be in the same position as the third position or the fourth position. Furthermore, for example, the second position may be in the same position as the third position or the fourth position.

[0189] Furthermore, the knurled portion 10 may also include a curved portion with a curved planar shape in combination with the straight portion and the corner portion. However, from the viewpoint of significantly obtaining the desired effect of the present invention, the planar shape of the knurled portion 10 preferably includes only the straight portion and the corner portion.

[0190] In the above embodiment, for the planar shape of the knurled portion 10, an example is shown where the virtual straight lines 140 and 240, and the virtual line segments 141-144, 241-244 are parallel to the width direction TD of the elongated film 1. However, these virtual straight lines 140 and 240, and the virtual line segments 141-144, 241-244 may also be non-parallel to the width direction TD. However, it is preferable that the virtual straight lines 140 and 240, and the virtual line segments 141-144, 241-244 are non-parallel to the length direction MD of the elongated film 1.

[0191] [3. Manufacturing method of long strip film]

[0192] The aforementioned strip film can be manufactured by a manufacturing method that includes, for example, irradiating the film with a laser before the knurling is formed. Hereinafter, the film before the knurling is formed is sometimes appropriately referred to as the "pre-processing film".

[0193] Typically, the pre-processing film is continuously transported along its length while being irradiated with a laser. When the laser irradiates at least one surface of the pre-processing film, localized thermal melting or ablation occurs at the laser-irradiated location. Therefore, at the laser-irradiated location, the pre-processing film can be deformed into convex and concave shapes, which function as uneven portions.

[0194] In the formation of the knurling section using such a laser, no mechanical force is required, thus residual stress in the knurling section is less likely to remain. Therefore, it is possible to suppress the generation of fractures in the strip film originating from the knurling section. Furthermore, even when using a thin pre-processing film, film fracture during knurling section formation is easily suppressed. Consequently, it is possible to suppress the generation of foreign matter resulting from the formation of the knurling section.

[0195] When irradiating the above-mentioned laser, the laser is directed to the irradiation point P (reference point) of the pre-processed film. Figure 8 and Figure 9 The laser moves in a manner that depicts the planar shape of the knurled portion to be formed. Thus, irregularities are formed along the trajectory of the laser's irradiation point P, thereby enabling the formation of a knurled portion with the desired planar shape.

[0196] When the laser irradiation point P is moved, the irradiation point P preferably traces the planar shape of the knurled part continuously along the midline (in one stroke). This allows the laser irradiation to be maintained during the formation of a knurled part. Therefore, deviations in the shape of the knurled part can be suppressed, and thus, the knurled part can be formed stably.

[0197] The moving speed of the laser irradiation point P can be arbitrarily set within a range that allows the desired knurling to be formed. Specifically, the moving speed is preferably 500 mm / s or more, more preferably 1000 mm / s or more, particularly preferably 1500 mm / s or more, preferably 10000 mm / s or less, more preferably 9000 mm / s or less, and particularly preferably 8000 mm / s or less. When the moving speed of the laser irradiation point P is at or above the lower limit of the above range, the drawing time can be shortened, and the knurling can be formed at high speed. Furthermore, when the moving speed of the laser irradiation point P is at or below the upper limit of the above range, since the overshoot caused by the inertia of the moving parts (mirrors, etc.) included in the laser optical system can be suppressed, deformation of the desired shape and the roundness of the corners can be suppressed.

[0198] Examples of laser irradiation devices, or laser devices, include ArF excimer lasers, KrF excimer lasers, XeCl excimer lasers, YAG lasers (especially third or fourth harmonic lasers), YLF or YVO4 solid-state lasers (especially third or fourth harmonic lasers), Ti:S lasers, semiconductor lasers, fiber lasers, and carbon dioxide lasers. Among these laser devices, carbon dioxide lasers are preferred from the viewpoint of being relatively inexpensive and effectively providing power suitable for film processing.

[0199] The laser power is preferably 1W or more, more preferably 5W or more, even more preferably 15W or more, preferably 120W or less, more preferably 100W or less, even more preferably 80W or less, and even more preferably 70W or less. By setting the laser power to the lower limit of the above range or above, insufficient laser irradiation can be suppressed, and knurling can be formed stably. Furthermore, by setting the laser power to the upper limit of the above range or below, the formation of through-holes in the film can be suppressed.

[0200] [4. Composition of the long strip membrane]

[0201] As the aforementioned long strip film, a resin film is typically used. This resin film can be a stretched film or an unstretched film. Furthermore, the resin film can be a single-layer film having only a substrate layer, or a multilayer film having any further layers in combination with the substrate layer.

[0202] As the substrate layer, a layer formed of resin is typically used. Various resins can be used depending on the application of the strip film, with cyclic olefin resins and (meth)acrylic resins being preferred. Generally, films with a substrate layer formed of cyclic olefin resin or (meth)acrylic resin tend to have poor winding properties because they easily trap air during winding. In contrast, forming the aforementioned knurled portion improves winding properties and typically effectively suppresses misalignment, tightness, looseness, and lateral twisting.

[0203] Cyclic olefin resins are resins containing cyclic olefin polymers. Cyclic olefin polymers have excellent mechanical properties, heat resistance, transparency, low moisture absorption, dimensional stability, and lightweight properties.

[0204] Cyclic olefin polymers refer to polymers whose structural units have an alicyclic structure. Cyclic olefin polymers can be polymers with an alicyclic structure in the main chain, polymers with an alicyclic structure in the side chains, polymers with an alicyclic structure in both the main chain and side chains, and mixtures of two or more of these in any ratio. From the viewpoint of mechanical strength and heat resistance, polymers with an alicyclic structure in the main chain are preferred.

[0205] Examples of alicyclic structures include saturated alicyclic hydrocarbons (cycloalkanes) and unsaturated alicyclic hydrocarbons (cycloolefins, alicyclic hydrocarbons). From the viewpoint of mechanical strength and heat resistance, cycloalkanes and cycloolefins are preferred, with cycloalkanes being particularly preferred.

[0206] For each alicyclic structure, the number of carbon atoms constituting the alicyclic structure is preferably 4 or more, more preferably 5 or more, more preferably 30 or less, more preferably 20 or less, and particularly preferably 15 or less. When the number of carbon atoms constituting the alicyclic structure is within this range, the mechanical strength, heat resistance, and moldability of the resin are highly balanced.

[0207] In cyclic olefin polymers, the proportion of structural units with alicyclic structures is preferably 55% by weight or more, more preferably 70% by weight or more, and particularly preferably 90% by weight or more. When the proportion of structural units with alicyclic structures in the cyclic olefin polymer is within this range, good transparency and heat resistance are observed.

[0208] Examples of cyclic olefin polymers include norbornene polymers, monocyclic cyclic olefin polymers, cyclic conjugated diene polymers, vinyl alicyclic hydrocarbon polymers, and their hydrides. Among these, norbornene polymers and their hydrides are particularly preferred due to their good formability.

[0209] Examples of norbornene-based polymers and their hydrides include: ring-opening polymers of monomers having a norbornene structure and their hydrides; and addition polymers of monomers having a norbornene structure and their hydrides. Furthermore, examples of ring-opening polymers of monomers having a norbornene structure include ring-opening homopolymers of a single monomer having a norbornene structure, ring-opening copolymers of two or more monomers having a norbornene structure, and ring-opening copolymers of a monomer having a norbornene structure and other monomers capable of copolymerizing therewith. Moreover, examples of addition polymers of monomers having a norbornene structure include addition homopolymers of a single monomer having a norbornene structure, addition copolymers of two or more monomers having a norbornene structure, and addition copolymers of a monomer having a norbornene structure and other monomers capable of copolymerizing therewith. Among these, hydrides of ring-opening polymers of monomers having a norbornene structure are particularly preferred from the viewpoints of moldability, heat resistance, low moisture absorption, dimensional stability, and lightweight properties.

[0210] The weight-average molecular weight (Mw) of the cyclic olefin polymer is preferably 10,000 or more, more preferably 15,000 or more, particularly preferably 20,000 or more, preferably 100,000 or less, more preferably 80,000 or less, and particularly preferably 50,000 or less. When the weight-average molecular weight is within the above range, the mechanical strength and molding processability of the resin are highly balanced.

[0211] The molecular weight distribution (weight-average molecular weight (Mw) / number-average molecular weight (Mn)) of the cyclic olefin polymer is preferably 1.2 or more, more preferably 1.5 or more, particularly preferably 1.8 or more, preferably 3.5 or less, more preferably 3.0 or less, and particularly preferably 2.7 or less. When the molecular weight distribution is at or above the lower limit of the above range, the polymer productivity can be improved and manufacturing costs can be reduced. Furthermore, when the molecular weight distribution is below the upper limit, since the amount of low molecular weight components is reduced, relaxation under high-temperature exposure can be suppressed, and the stability of the membrane can be improved.

[0212] The weight-average molecular weight and number-average molecular weight are the weight-average molecular weights converted from polyisoprene or polystyrene determined by gel permeation chromatography using cyclohexane as a solvent. However, in the above gel permeation chromatography method, toluene can also be used as a solvent if the sample is insoluble in cyclohexane.

[0213] The glass transition temperature of the cyclic olefin polymer is preferably 130°C or higher, more preferably 135°C or higher, more preferably 150°C or lower, and even more preferably 145°C or lower. When the glass transition temperature is above the lower limit of the above range, the film exhibits good durability at high temperatures. Furthermore, when the glass transition temperature is below the upper limit of the above range, stretching treatment can be easily performed.

[0214] As the aforementioned cyclic olefin polymer, for example, the cyclic olefin polymer described in International Publication No. 2017 / 145718 can be used.

[0215] The proportion of cyclic olefin polymer in the cyclic olefin resin is preferably 50% to 100% by weight, more preferably 70% to 100% by weight, and particularly preferably 90% to 100% by weight. Sufficient heat resistance and transparency can be obtained when the proportion of polymer is within the above range.

[0216] Provided that the effects of the present invention are not significantly impaired, the cyclic olefin resin may include any component other than the cyclic olefin polymer. Examples of any component include: colorants such as pigments and dyes; fluorescent whitening agents; dispersants; heat stabilizers; light stabilizers; ultraviolet absorbers; antistatic agents; antioxidants; lubricants, etc. Furthermore, these may be used alone or in combination of two or more in any ratio.

[0217] (Meth)acrylic resins are resins containing (meth)acrylic acid polymers. (Meth)acrylic acid polymers refer to polymers of acrylic acid or acrylic acid derivatives, such as acrylic acid, acrylates, acrylamide, acrylonitrile, methacrylic acid, and methacrylates, as well as copolymers. (Meth)acrylic acid polymers are strong and rigid, thus enabling the creation of films with high mechanical strength.

[0218] As a (meth)acrylic acid polymer, a polymer comprising structural units having a structure obtained by polymerizing (meth)acrylic acid esters is preferred. Examples of (meth)acrylic acid esters include, for instance, alkyl esters of (meth)acrylic acid. Among these, compounds having a structure derived from (meth)acrylic acid and an alkanol or cycloalkanol having 1 to 15 carbon atoms are preferred. Furthermore, compounds having a structure derived from (meth)acrylic acid and an alkanol having 1 to 8 carbon atoms are more preferred. By reducing the number of carbon atoms as described above, the elongation upon membrane rupture can be reduced.

[0219] Specific examples of acrylates include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, sec-butyl acrylate, tert-butyl acrylate, n-hexyl acrylate, cyclohexyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, n-decyl acrylate, and n-dodecyl acrylate.

[0220] In addition, specific examples of methacrylates include methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, sec-butyl methacrylate, tert-butyl methacrylate, n-hexyl methacrylate, n-octyl methacrylate, 2-ethylhexyl methacrylate, n-decyl methacrylate, and n-dodecyl methacrylate.

[0221] Furthermore, as long as it does not significantly impair the effects of the present invention, the aforementioned (meth)acrylates may have substituents such as hydroxyl groups or halogen atoms. Examples of (meth)acrylates having such substituents include 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, 3-chloro-2-hydroxypropyl methacrylate, and glycidyl methacrylate. These may be used individually or in combination of two or more in any ratio.

[0222] Furthermore, the (meth)acrylic acid polymer can be a polymer of acrylic acid or acrylic acid derivatives alone, or a copolymer of acrylic acid or acrylic acid derivatives and any monomer capable of copolymerizing therewith. Examples of arbitrary monomers include, for instance, α,β-ene unsaturated carboxylic acid ester monomers other than the aforementioned (meth)acrylic acid esters, as well as α,β-ene unsaturated carboxylic acid monomers, alkenyl aromatic monomers, conjugated diene monomers, non-conjugated diene monomers, carboxylic acid unsaturated alcohol esters, and olefin monomers. These can be used individually or in combination of two or more in any ratio.

[0223] When the (meth)acrylic polymer contains any monomer, the amount of structural units in the (meth)acrylic polymer having a structure obtained by polymerizing any monomer is preferably 50% by weight or less, more preferably 15% by weight or less, and particularly preferably 10% by weight or less.

[0224] Among these (meth)acrylic polymers, polymethacrylate is preferred, and polymethyl methacrylate is more preferred.

[0225] As the aforementioned (meth)acrylic acid polymer, the (meth)acrylic acid polymer described, for example, in International Publication No. 2017 / 145718, can be used.

[0226] The proportion of (meth)acrylic acid polymer in the (meth)acrylic resin is preferably 50% to 100% by weight, more preferably 70% to 100% by weight, and particularly preferably 90% to 100% by weight. Sufficient heat resistance and transparency can be obtained when the proportion of polymer is within the above range.

[0227] Provided that the effects of the invention are not significantly impaired, (meth)acrylic resins can include any component other than (meth)acrylic polymers. Examples of any component may be given, for instance, those that are the same as any component that can be included in cyclic olefin resins. Furthermore, any component may be used alone or in combination of two or more in any ratio.

[0228] The aforementioned substrate layer can be manufactured by molding resin using a suitable film forming method. Examples of film forming methods include casting, extrusion molding, and blow molding. Among these, solvent-free melt extrusion is preferred from the perspectives of effectively reducing residual volatile components, environmental protection and working conditions, and excellent manufacturing efficiency. As a melt extrusion method, die-blowing can be used; however, T-die extrusion is preferred from the perspectives of excellent productivity and thickness accuracy.

[0229] When using a multilayer film with two or more layers as a strip film, the multilayer film preferably has a substrate layer and a functional layer. The functional layer can be disposed on one side of the substrate layer or on both sides. Preferably, the functional layer is disposed on the knurled side of the substrate layer, and more preferably, the knurling is provided on the surface of the functional layer.

[0230] Examples of such functional layers include antistatic layers, hard coatings, anti-adhesion layers, and easy-to-adhere layers.

[0231] An antistatic layer is a layer with a low surface resistance. The preferred surface resistance value for an antistatic layer is 1.0 × 10⁻⁶. 6 Ω / □ or higher, more preferably 1.0×10 7 Ω / □ or higher, preferably 1.0 × 10⁻⁶ 8 Ω / □ or higher, preferably 1.0 × 10 10 Ω / □ or less, more preferably 5.0 × 10 9 Ω / □ or less, with 1.0 × 10⁻⁶ being particularly preferred. 9 Ω / □ or less. The surface resistivity can be measured according to JIS K6911 using a digital super-insulation / micro-current meter (Hioki Electric Co., Ltd. "DSM-8104"). Such an antistatic layer can be formed, for example, from a resin containing conductive particles such as metal oxide particles and polymers.

[0232] A hard coating refers to a layer with high hardness. When the specific hardness of the hard coating is expressed in terms of JIS pencil hardness, it is preferably B or higher, more preferably HB or higher, and particularly preferably H or higher. Here, JIS pencil hardness is the hardness of a pencil that begins to damage when the surface of the layer is scratched by a pencil of various hardness tilted at 45° and subjected to a 500g load from above, according to JIS K5600-5-4. Such a hard coating can be formed, for example, by resin.

[0233] An anti-adhesion layer is a layer with a rough surface that inhibits adhesion between films when overlapped. Such an anti-adhesion layer can be formed, for example, from a resin containing polymers and particles.

[0234] An easy-to-adhesive layer is a layer that exhibits high adhesion when its surface is bonded to other components. Such an easy-to-adhesive layer can be formed, for example, from a resin containing a polymer.

[0235] Of the aforementioned functional layers, an easy-to-adhere layer is preferred. The easy-to-adhere layer is preferably a layer containing a water-based resin. Aqueous resin refers to a resin that can be prepared in the form of a solution or dispersion using water as a medium. By applying an aqueous solution or dispersion containing the aqueous resin to the surface of the substrate layer and then drying it, a layer of aqueous resin can be formed on the surface of the substrate layer. Examples of aqueous resins include, for example, polyurethane resins, polyester resins, and emulsions of these resins; aqueous polyurethane resins are preferred.

[0236] As the aforementioned functional layer, the functional layer described in, for example, International Publication No. 2017 / 145718 can be used.

[0237] [5. Uses of long strip films]

[0238] Strip films can be used in a wide range of applications, and are particularly preferred as optical films. Examples of optical films include phase retardation films, polarizer protective films, and optical compensation films. Among these, the strip films are preferably used as polarizer protective films.

[0239] Polarizers typically consist of a polarizer and a protective film. Therefore, when using the aforementioned strip film as a protective film for a polarizer, it is usually applied to the polarizer.

[0240] When bonding the strip film to the polarizer, the strip film can be bonded directly to the polarizer without an adhesive, or it can be bonded with an adhesive. Furthermore, the strip film can be bonded to only one side of the polarizer, or it can be bonded to both sides. If the strip film is bonded to only one side of the polarizer, another film with high transparency can be bonded to the other sides of the polarizer.

[0241] As a polarizer, a film manufactured, for example, by adsorbing iodine or dichroic dye onto a polyvinyl alcohol film and then uniaxially stretching it in a boric acid bath can be used. Furthermore, a film manufactured, for example, by adsorbing iodine or dichroic dye onto a polyvinyl alcohol film and stretching it, thereby modifying a portion of the polyvinyl alcohol units in the molecular chain into polyvinylene units, can be used. Moreover, as a polarizer, polarizers that have the function of separating polarized light into reflected and transmitted light, such as lattice polarizers, multilayer polarizers, and cholesteric liquid crystal layer polarizers, can be used. Among these, a polarizer containing polyvinyl alcohol is preferred. The polarization degree of the polarizer is preferably 98% or more, more preferably 99% or more. Furthermore, the average thickness of the polarizer is preferably 5 μm to 80 μm.

[0242] Optically transparent adhesives can be used as adhesives for bonding strip films and polarizers. Examples of adhesives include water-based adhesives, solvent-based adhesives, two-component curing adhesives, UV-curing adhesives, and pressure-sensitive adhesives. Among these, water-based adhesives and UV-curing adhesives are preferred, and polyvinyl alcohol-based water-based adhesives are particularly preferred. Adhesives such as those described in International Publication No. 2017 / 145718 can be used. Furthermore, an adhesive can be used alone or in combination of two or more in any ratio.

[0243] When using an adhesive to bond the polarizer and the strip membrane, the adhesive can be cured as needed after bonding. The method for curing the adhesive depends on the type of adhesive and can be appropriate. For example, when using a light-curing adhesive, it can be cured by irradiation with active energy rays such as ultraviolet light.

[0244] When using an adhesive, an adhesive layer is provided between the polarizer and the strip film. The average thickness of this adhesive layer is preferably 0.05 μm or more, more preferably 0.1 μm or more, more preferably 5 μm or less, and more preferably 1 μm or less.

[0245] Example

[0246] The present invention will now be specifically described with reference to the embodiments shown. However, the present invention is not limited to the embodiments shown below, and can be implemented in any manner without departing from the scope of the patent claims and their equivalents. In the following description, unless otherwise stated, "%" and "parts" refer to weight. Furthermore, unless otherwise stated, the operations described below are performed at normal temperature and pressure in an atmospheric environment.

[0247] [Evaluation Method]

[0248] Methods for measuring the height of concave and convex parts

[0249] The height of the knurled portion of the strip film is measured using, for example, a three-dimensional surface profilometer (ZYGO's "NewView5000").

[0250] [Method for determining the radius of curvature of a corner]

[0251] The radius of curvature of the corners of the knurled portion of the strip film is measured using, for example, a three-dimensional surface profilometer (ZYGO "NewView5000").

[0252] [Example 1]

[0253] [Manufacturing of the substrate layer]

[0254] The granules of cyclic olefin resin (ZEONOR, manufactured by Zeon Corporation of Japan, glass transition temperature 135°C) were dried for 2 hours at 70°C using a hot air dryer with air circulation. The dried granules were then fed to a facility with… The screw-type resin melt mixing mill and T-mode film melt extrusion molding machine are used to extrude and mold long strips of substrate layer (thickness 50μm, width 1500mm, length 4000m) under molding conditions of molten resin temperature 270℃ and T-die width 1700mm.

[0255] [Preparation of the pre-treatment film (formation of the easily adhesive layer)]

[0256] A water-based polyether polyurethane resin dispersion with a solid content of 2% was obtained by mixing 100 parts by weight of an aqueous dispersion of polyether polyurethane (superflex870 manufactured by Daiichi Kogyo Pharmaceutical Co., Ltd.) as a polyurethane, 15 parts by weight of an epoxy compound (DENACOLEX313 manufactured by Nagase ChemteX Co., Ltd.) as a crosslinking agent, 8 parts by weight of an aqueous dispersion of silica particles (snowtexMP1040 manufactured by Nissan Chemical Co., Ltd.; average particle size 120 nm) as a lubricant, and 8 parts by weight of an aqueous dispersion of silica particles (snowtexXL manufactured by Nissan Chemical Co., Ltd.; average particle size 50 nm) as a wetting agent, 0.5% by weight relative to the total solid content, and water.

[0257] On one side of the aforementioned substrate layer, an aqueous dispersion of the aforementioned water-based polyurethane resin is applied using a reverse roller method to a thickness of 45 nm after drying, and then dried at 90°C. This forms an easy-to-adhere layer on one side of the substrate layer, resulting in a pre-treatment film with a multilayer structure consisting of a substrate layer and an easy-to-adhere layer.

[0258] [Form of the knurled part]

[0259] The pre-treatment film was transported along its length at a speed of 30 m / min. Then, the surfaces of the easily bonded layers at both ends of the transported pre-treatment film in the width direction were irradiated with a laser to form multiple knurled sections, resulting in a long strip film. A CO2 laser irradiation device (COHERENT "J3 series", laser wavelength 9.4 μm) was used as the laser irradiation device. Furthermore, the laser irradiation power was set to 50%. Then, laser irradiation was performed by moving the laser irradiation point at a speed of 7000 mm / s using a scanning galvanometer to depict the desired planar shape of the knurled sections.

[0260] Figure 20 and Figure 21 This is a schematic top view showing the planar shape of the knurled portion 1000 formed in Embodiment 1 of the present invention.

[0261] Through the irradiation of the aforementioned laser, a concave-convex portion with a width W of 0.2 mm is formed. Figure 20 and Figure 21 The knurled portion 1000 is shown in planar shape. The knurled portion 1000 has a ring shape including a first thread group portion 1100, a second thread group portion 1200, a first connecting portion 1300 and a second connecting portion 1400 that are connected to each other.

[0262] The first line group portion 1100 has a serrated shape comprising a plurality of consecutive straight lines. Specifically, the first line group portion 1100 has a straight line portion 1111 extending from the first position 1101 to the corner portion 1131, a straight line portion 1112 extending from the corner portion 1131 to the corner portion 1132, a straight line portion 1113 extending from the corner portion 1132 to the corner portion 1133, a straight line portion 1114 extending from the corner portion 1133 to the corner portion 1134, a straight line portion 1115 extending from the corner portion 1134 to the corner portion 1135, and a straight line portion 1136 extending from the corner portion 1135 to the corner portion 1136. 116, a straight section 1117 extending from corner 1136 to corner 1137, a straight section 1118 extending from corner 1137 to corner 1138 (corresponding to the second position), a straight section 1119 extending from corner 1138 to corner 1139, a straight section 1120 extending from corner 1139 to corner 1140, a straight section 1121 extending from corner 1140 to corner 1141, and a straight section 1122 extending from corner 1141 to corner 1142.

[0263] The second line group 1200 has a serrated shape comprising a plurality of consecutive straight lines. Specifically, the second line group 1200 has a straight line 1211 extending from the third position 1201 to the corner 1231, a straight line 1212 extending from the corner 1231 to the corner 1232, a straight line 1213 extending from the corner 1232 to the corner 1233, a straight line 1214 extending from the corner 1233 to the corner 1234, a straight line 1215 extending from the corner 1234 to the corner 1235, and a straight line 1216 extending from the corner 1235 to the corner 1236. 216, a straight section 1217 extending from corner 1236 to corner 1237, a straight section 1218 extending from corner 1237 to corner 1238 (equivalent to the fourth position), a straight section 1219 extending from corner 1238 to corner 1239, a straight section 1220 extending from corner 1239 to corner 1240, a straight section 1221 extending from corner 1240 to corner 1241, and a straight section 1222 extending from corner 1241 to corner 1242.

[0264] The first connecting portion 1300 is formed parallel to the straight portion 1111 as a straight line connecting the first position 1101 of the first line group portion 1100 and the corner portion 1242 of the second line group portion 1200.

[0265] The second connecting portion 1400 is formed parallel to the straight portion 1211 as a straight line connecting the corner portion 1142 of the first line group portion 1100 and the third position 1201 of the second line group portion 1200.

[0266] The straight sections 1111 to 1122 included in the first line group 1100 and the straight sections 1211 to 1222 included in the second line group 1200 are all straight lines with the same length (1.1 mm).

[0267] All corner portions 1131-1142 and 1231-1242 included in the knurled portion 1000 have an angle of 90°. Furthermore, the radius of curvature of all corner portions 1131-1142 and 1231-1242 included in the knurled portion 1000 is 0.2 mm. Moreover, the aforementioned corner portions 1131-1142 and 1231-1242 are positioned at different locations with a fixed interval D = 0.4 mm in the width direction. The deviation of the interval D between these corner portions is 0.05 mm.

[0268] The length L of the knurled portion 1000 on the membrane length direction MD MD The length L of the knurled portion 1000 on the membrane width direction TD is 1.9mm. TD The diameter is 9.4 mm. In addition, the spacing of the knurled portions 1000 on the membrane length direction MD is 4.2 mm.

[0269] Furthermore, the height of the uneven portion forming the knurled part 1000 was measured, and the average height of the corner was found to be 7 μm.

[0270] [Evaluation of the precision of the knurling formation]

[0271] The positions of the corners 1131-1142 and 1231-1242 of the knurled portion 1000 were measured. As a result, the following were confirmed.

[0272] The corner portions 1132, 1134, 1136, 1138, 1140, and 1142 of the first line group 1100 are positioned on a virtual straight line 140 with a thickness of 0.1 mm that passes through the first position 1101 and the corner portion 1138. Furthermore, the virtual straight line 140 is parallel to the membrane width direction TD.

[0273] The corner portions 1232, 1234, 1236, 1238, 1240, and 1242 of the second line group 1200 are positioned on a virtual straight line 240 with a thickness of 0.1 mm that passes through the third position 1201 and the corner portion 1238. Furthermore, the virtual straight line 240 is parallel to the membrane width direction TD.

[0274] The corner 1131 is positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting the first position 1101 and the corner 1132.

[0275] Corner 1133 is positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 1132 and corner 1134.

[0276] Corner 1135 is positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 1134 and corner 1136.

[0277] Corner 1137 is positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 1136 and corner 1138.

[0278] Corner 1139 is positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 1138 and corner 1140.

[0279] Corner 1141 is positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 1140 and corner 1142.

[0280] The corner 1231 is positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting the third position 1201 and the corner 1232.

[0281] Corner 1233 is positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 1232 and corner 1234.

[0282] Corner 1235 is positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 1234 and corner 1236.

[0283] Corner 1237 is positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 1236 and corner 1238.

[0284] Corner 1239 is positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 1238 and corner 1240.

[0285] Corner 1241 is positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 1240 and corner 1242.

[0286] At this point, all the aforementioned virtual circles have the same diameter.

[0287] [Evaluation of coilability]

[0288] The elongated film with the knurled portion formed as described above is further transported along its length, and wound 4000m along its length with a core of 6 inches in diameter as the center and a winding tension of 120N to obtain a film roll. The obtained film roll is observed, and the winding properties of the elongated film are evaluated.

[0289] [Example 2]

[0290] The pre-treatment film was manufactured using the same method as in Example 1. The surfaces of the left and right ends of the pre-treatment film in the width direction, on the easy-to-adhere layer side, were irradiated with a laser under the same conditions as in Example 1 to form multiple knurled sections, resulting in a strip film.

[0291] Figure 22 and Figure 23 This is a schematic top view showing the planar shape of the knurled portion 2000 formed in Embodiment 2 of the present invention.

[0292] Through the irradiation of the aforementioned laser, a concave-convex portion with a width W of 0.2 mm is formed. Figure 22 and Figure 23The knurled portion 2000 is shown in planar shape. The knurled portion 2000 has a ring shape including a first thread group portion 2100, a second thread group portion 2200, a first connecting portion 2300 and a second connecting portion 2400 that are connected to each other.

[0293] The first line group portion 2100 has a serrated shape comprising a plurality of consecutive straight lines. Specifically, the first line group portion 2100 has a straight line portion 2111 extending from corner 2131 (corresponding to the first position) to corner 2132, a straight line portion 2112 extending from corner 2132 to corner 2133, a straight line portion 2113 extending from corner 2133 to corner 2134, a straight line portion 2114 extending from corner 2134 to corner 2135, a straight line portion 2115 extending from corner 2135 to corner 2136, a straight line portion 2116 extending from corner 2136 to corner 2137, and a straight line portion 2118 extending from corner 2137 to corner 2138. Line portion 2117, straight line portion 2118 extending from corner portion 2138 to corner portion 2139 (corresponding to the second position), straight line portion 2119 extending from corner portion 2139 to corner portion 2140, straight line portion 2120 extending from corner portion 2140 to corner portion 2141, straight line portion 2121 extending from corner portion 2141 to corner portion 2142, straight line portion 2122 extending from corner portion 2142 to corner portion 2143, straight line portion 2123 extending from corner portion 2143 to corner portion 2144, and straight line portion 2124 extending from corner portion 2144 to corner portion 2145.

[0294] The second line group 2200 has a serrated shape comprising a plurality of consecutive straight lines. Specifically, the second line group 2200 has a straight line 2211 extending from corner 2231 (corresponding to the third position) to corner 2232, a straight line 2212 extending from corner 2232 to corner 2233, a straight line 2213 extending from corner 2233 to corner 2234, a straight line 2214 extending from corner 2234 to corner 2235, a straight line 2215 extending from corner 2235 to corner 2236, a straight line 2216 extending from corner 2236 to corner 2237, and a straight line 2216 extending from corner 2237 to corner 2238. Line portion 2217, straight line portion 2218 extending from corner portion 2238 to corner portion 2239 (equivalent to the fourth position), straight line portion 2219 extending from corner portion 2239 to corner portion 2240, straight line portion 2220 extending from corner portion 2240 to corner portion 2241, straight line portion 2221 extending from corner portion 2241 to corner portion 2242, straight line portion 2222 extending from corner portion 2242 to corner portion 2243, straight line portion 2223 extending from corner portion 2243 to corner portion 2244, and straight line portion 2224 extending from corner portion 2244 to corner portion 2245.

[0295] The first connecting portion 2300 has a straight portion 2311 extending from the corner portion 2131 of the first line group portion 2100 to the corner portion 2331, and a straight portion 2312 extending from the corner portion 2331 to the corner portion 2245 of the second line group portion 2200.

[0296] The second connecting portion 2400 has a straight portion 2411 extending from the corner portion 2145 of the first line group portion 2100 to the corner portion 2431, and a straight portion 2412 extending from the corner portion 2431 to the corner portion 2231 of the second line group portion 2200.

[0297] The straight sections 2111, 2113, 2115, 2117, 2119, 2121 and 2123 included in the first line group 2100, and the straight sections 2211, 2213, 2215, 2217, 2219, 2221 and 2223 included in the second line group 2200 are all straight lines with the same length (1.0 mm).

[0298] Furthermore, the straight sections 2112, 2114, 2116, 2118, 2120, 2122 and 2124 included in the first line group 2100, and the straight sections 2212, 2214, 2216, 2218, 2220, 2222 and 2224 included in the second line group 2200 are all straight lines with the same length (0.6mm).

[0299] All corner portions 2131-2145, 2231-2245, 2331, and 2431 included in the knurled portion 2000 have an angle of 90°. Furthermore, the radius of curvature of all corner portions 2131-2145, 2231-2245, 2331, and 2431 included in the knurled portion 2000 is 0.2 mm. Moreover, the aforementioned corner portions 2131-2145, 2231-2245, 2331, and 2431 are all positioned at different locations with a fixed interval D = 0.3 mm in the width direction. The deviation of the interval D between these corner portions is 0.05 mm.

[0300] The length L of the knurled portion 2000 on the membrane length direction MD MD The length L of the knurled portion 2000 on the film thickness direction TD is 1.2mm. TD The diameter is 9.5 mm. In addition, the spacing of the knurled portions 2000 on the membrane length direction MD is 4.2 mm.

[0301] Furthermore, the height of the uneven portion forming the knurled part 2000 was measured, and the average height of the corner was found to be 7 μm.

[0302] [Evaluation of the precision of the knurling formation]

[0303] The positions of the corners 2131-2145 and 2231-2245 of the knurled portion 2000 were measured. As a result, the following were confirmed.

[0304] The corner portions 2131, 2133, 2135, 2137, 2139, 2141, 2143, and 2145 of the first line group 2100 are positioned on a virtual straight line 140 with a thickness of 0.1 mm passing through corner portions 2131 and 2139. Furthermore, the virtual straight line 140 is parallel to the membrane width direction TD.

[0305] The corner portions 2231, 2233, 2235, 2237, 2239, 2241, 2243, and 2245 of the second line group 2200 are positioned on a virtual straight line 140 with a thickness of 0.1 mm passing through corner portions 2231 and 2239. Furthermore, the virtual straight line 240 is parallel to the membrane width direction TD.

[0306] Corner 2132 is positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 2131 and corner 2133.

[0307] Corner 2134 can be positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 2133 and corner 2135.

[0308] Corner 2136 can be positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 2135 and corner 2137.

[0309] Corner 2138 is positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 2137 and corner 2139.

[0310] Corner 2140 can be positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 2139 and corner 2141.

[0311] Corner 2142 is positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 2141 and corner 2143.

[0312] Corner 2144 is positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 2143 and corner 2145.

[0313] Corner 2232 is positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 2231 and corner 2233.

[0314] Corner 2234 can be positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 2233 and corner 2235.

[0315] Corner 2236 can be positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 2235 and corner 2237.

[0316] Corner 2238 can be positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 2237 and corner 2239.

[0317] Corner 2240 is positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 2239 and corner 2241.

[0318] Corner 2242 is positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 2241 and corner 2243.

[0319] Corner 2244 can be positioned on a virtual circle (a circle drawn with a line of thickness of 0.1 mm) with the diameter of the virtual line segment connecting corner 2243 and corner 2245.

[0320] At this point, all the aforementioned virtual circles have the same diameter.

[0321] [Evaluation of coilability]

[0322] The strip film with the knurled portion formed as described above is further transported along its length and wound 4000m along its length with a core of 6 inches in diameter as the center and a winding tension of 120N to obtain a film roll. The obtained film roll is observed, and the winding properties of the strip film are evaluated.

[0323] [Comparative Example 1]

[0324] Figure 24 This is a schematic top view showing the planar shape of the knurled portion 3000 formed in Comparative Example 1.

[0325] like Figure 24As shown, the planar shape of the knurled portion 3000 is changed to the same shape as in Example 1 of International Publication No. 2017 / 145718. Otherwise, the strip film and film roll are manufactured and evaluated using the same method as in Example 1. Figure 24 As shown, in the formed knurled portion 3000, a portion of the corner portion 3010 is located at the same position in the film width direction TD.

[0326] In the knurled portion 3000 formed in Comparative Example 1, Figure 24 The angle of the corner indicated by reference numeral 3010 is 90°, and the angle of the corner indicated by reference numeral 3020 is 135°. The length L of the knurled portion 3000 on the film length direction MD is... MD The length L of the knurled portion 3000 on the membrane width direction TD is 1.2mm. TD The length of the knurled portion 3000 is 9.3 mm, and the spacing of the knurled portion 3000 along the length direction MD is 4.2 mm. Furthermore, the height of the irregular portion forming the knurled portion 3000 was measured, and the average height of the corner portion was found to be 7 μm.

[0327] [Comparative Example 2]

[0328] The laser irradiation power used to form the knurled portion was changed to 60% of its original power, and the winding tension when winding the strip film was changed to 150 N. Otherwise, the strip film and film roll were manufactured and evaluated using the same method as in Comparative Example 1. The planar shape of the knurled portion formed in Comparative Example 2 was the same as in Comparative Example 1, but the average height of the corners of the uneven portions forming the knurled portion was 12 μm.

[0329] [result]

[0330] The results of the examples and comparative examples are shown in the table below.

[0331] [Table 1]

[0332] [Table 1. Results of the Examples and Comparative Examples]

[0333] Adhesion Rolled appearance Volume offset Uneven (curved) Example 1 none good none none Example 2 none good none none Comparative Example 1 none bad Partially generated Partially generated Comparative Example 2 Partially generated good none none

[0334] Explanation of reference numerals in the attached figures

[0335] 1: Long strip film

[0336] 1U: The side of the long strip film

[0337] 10: Knurled section

[0338] 20: Uneven parts

[0339] 21: Concave

[0340] 22: convex part

[0341] 30: Knurling section

[0342] 40: Knurling section

[0343] 50: Knurled section

[0344] 100: First Line Group

[0345] 111: First straight section

[0346] 112: Second straight section

[0347] 113: Third straight section

[0348] 114: Fourth straight section

[0349] 115: Fifth straight section

[0350] 116: Sixth straight section

[0351] 117: Seventh straight section

[0352] 118: Eighth straight section

[0353] 121: First position

[0354] 122: Second position

[0355] 131: First Corner

[0356] 132: Second corner

[0357] 133: Third Corner

[0358] 134: Fourth Corner

[0359] 135: Fifth Corner

[0360] 136: Sixth Corner

[0361] 137: The Seventh Corner

[0362] 140: First virtual line

[0363] 141: First virtual line segment

[0364] 142: Second virtual line segment

[0365] 143: Third virtual line segment

[0366] 144: Fourth virtual line segment

[0367] 151: First Virtual Circle

[0368] 152: Second Virtual Circle

[0369] 153: The Third Virtual Circle

[0370] 154: The Fourth Virtual Circle

[0371] 200: Second Line Group

[0372] 211: Ninth Straight Section

[0373] 212: Tenth Straight Line Section

[0374] 213: The Eleventh Straight Line

[0375] 214: Twelfth Straight Section

[0376] 215: Thirteenth Straight Section

[0377] 216: Fourteenth Straight Section

[0378] 217: Fifteenth Straight Section

[0379] 218: Sixteenth Straight Section

[0380] 221: Third position

[0381] 222: Fourth position

[0382] 231: The Eighth Corner

[0383] 232: Ninth Corner

[0384] 233: The Tenth Horn

[0385] 234: Eleventh Corner

[0386] 235: The Twelfth Corner

[0387] 236: The Tenth Triangle

[0388] 237: The Fourteenth Corner

[0389] 240: Second virtual line

[0390] 241: Fifth virtual line segment

[0391] 242: The sixth virtual line segment

[0392] 243: The Seventh Virtual Line Segment

[0393] 244: The Eighth Virtual Line Segment

[0394] 251: The Fifth Virtual Circle

[0395] 252: The Sixth Virtual Circle

[0396] 253: The Seventh Virtual Circle

[0397] 254: The Eighth Virtual Circle

[0398] 300: First connecting part

[0399] 311, 312, and 313: Line segment section

[0400] 331 and 332: Corners

[0401] 400: Second connecting part

[0402] 411, 412, and 413: Line segment section

[0403] 431 and 432: Corners

[0404] 500: First Line Group

[0405] 511: First straight section

[0406] 512: Second straight section

[0407] 513: Third straight section

[0408] 514: Fourth straight section

[0409] 515: Fifth straight section

[0410] 516: Sixth straight section

[0411] 517: Seventh Straight Section

[0412] 518: Eighth Straight Section

[0413] 600: Second Line Group

[0414] 611: Ninth Straight Section

[0415] 612: Tenth Straight Line Section

[0416] 613: The Eleventh Straight Line

[0417] 614: Twelfth Straight Line Section

[0418] 615: Thirteenth Straight Section

[0419] 616: Fourteenth Straight Section

[0420] 617: Fifteenth Straight Section

[0421] 618: Sixteenth straight section

[0422] 700: First connecting part

[0423] 800: Second connecting part

Claims

1. A strip film having a plurality of knurled portions formed by continuous linear irregularities on at least one side, wherein, Viewed from the thickness direction of the elongated film, the planar shape of the knurled portion includes a first thread group portion and a second thread group portion. The first line assembly includes: The first straight section extends in a straight line from the first position to the first corner. The second straight section extends in a straight line from the first corner to the second corner. The third straight section extends in a straight line from the second corner to the third corner. The fourth straight section extends in a straight line from the third corner to the fourth corner. The fifth straight section extends in a straight line from the fourth corner to the fifth corner. The sixth straight section extends in a straight line from the fifth corner to the sixth corner. The seventh straight section extends in a straight line from the sixth corner to the seventh corner, and The eighth straight section extends in a straight line from the seventh corner to the second position. The second line assembly includes: The ninth straight section extends in a straight line from the third position to the eighth corner. The tenth straight section extends in a straight line from the eighth corner to the ninth corner. The eleventh straight section extends in a straight line from the ninth corner to the tenth corner. The twelfth straight section extends in a straight line from the tenth corner to the eleventh corner. The thirteenth straight section extends in a straight line from the eleventh corner to the twelfth corner. The fourteenth straight section extends in a straight line from the twelfth to the tenth triangular section. The fifteenth straight section extends in a straight line from the tenth triangular section to the fourteenth triangular section, and... The sixteenth straight section extends in a straight line from the fourteenth corner to the fourth position. The first thread group and the second thread group are formed at different positions along the length of the elongated film. The first to fourteenth corners each independently have an angle of 80° to 100°. The corners are located at different positions along the width of the elongated membrane.

2. The elongated membrane according to claim 1, wherein, The deviation of the interval between the corners in the width direction of the elongated film is less than 1.00 mm.

3. The elongated membrane according to claim 1 or 2, wherein, When a first virtual straight line is drawn through the first and second positions using a line three times the width of the protrusions and recesses, the second corner, the fourth corner, and the sixth corner lie on the first virtual straight line. When a second virtual straight line is drawn through the third and fourth positions using a line three times thicker than the width of the protrusions and concavities, the ninth corner, the eleventh corner, and the tenth triangle are located on the second virtual straight line.

4. The elongated membrane according to claim 1 or 2, wherein, When a first virtual circle with a diameter equal to the diameter of a first virtual line segment connecting the first position and the second corner is drawn using a line three times thicker than the width of the raised portion, the first corner lies on the first virtual circle. When a second virtual circle with a diameter equal to the diameter of the second virtual line segment connecting the second and fourth corners is drawn using a line three times thicker than the width of the raised portion, the third corner is located on the second virtual circle. When a third virtual circle with a diameter equal to the diameter of the third virtual line segment connecting the fourth and sixth corners is drawn using a line three times thicker than the width of the raised and recessed portions, the fifth corner is situated on the third virtual circle. When a fourth virtual circle with a diameter equal to the fourth virtual line segment connecting the sixth corner and the second position is drawn using a line three times thicker than the width of the aforementioned protrusions and recesses, the seventh corner lies on the fourth virtual circle. When a fifth virtual circle is drawn with a diameter equal to three times the width of the raised portion, and the fifth virtual line segment connecting the third position and the ninth corner is used as the diameter, the eighth corner is located on the fifth virtual circle. When a sixth virtual circle, with a diameter equal to the sixth virtual line segment connecting the ninth and eleventh corners, is drawn using a line three times thicker than the width of the aforementioned protrusions, the tenth corner is situated on the sixth virtual circle. When a seventh virtual circle, with a diameter equal to the seventh virtual line segment connecting the eleventh corner and the tenth triangle, is drawn using a line three times thicker than the width of the aforementioned protrusions, the twelfth corner lies on the seventh virtual circle. When an eighth virtual circle with a diameter equal to the eighth virtual line segment connecting the tenth triangle and the fourth position is drawn using a line three times thicker than the width of the concave and convex portions, the fourteenth triangle is located on the eighth virtual circle.

5. The elongated membrane according to claim 4, wherein, The diameters of the first virtual circle to the eighth virtual circle are equal.

6. The elongated membrane according to claim 1 or 2, wherein, The first wire group and the second wire group do not intersect.

7. The elongated membrane according to claim 1 or 2, wherein, The elongated film has a substrate layer formed of cyclic olefin resin or (meth)acrylic resin.

Images