JP5567127B2 - Manufacturing method of polarizing plate - Google Patents

Description

The present invention relates to a method for producing a polarizing plate of an optical film used in a liquid crystal display device.
This application claims the benefit of the filing date of Korean Patent Application No. 10-2010-0050582 filed with the Korean Patent Office on May 28, 2010, the entire contents of which are included in this specification.

  A CRT (cathode ray tube), which is one of the display devices conventionally used, is mainly used for monitors such as TVs, measuring devices, information terminal devices, and the like. Due to the size of the sheath, it was not possible to respond positively to the demand for smaller and lighter electronic products.

  In order to replace such a CRT, a liquid crystal display device having the advantages of miniaturization and weight reduction has been actively developed, and recently, it has been developed so that it can sufficiently fulfill its role as a flat panel display device, and its demand is increasing. It has increased.

  The display principle of such a liquid crystal display device utilizes the optical anisotropy and polarization properties of the liquid crystal. The liquid crystal has an elongated molecular structure, an anisotropy having a directionality in the arrangement, and a polarization property in which the direction of the molecular arrangement changes depending on the size when placed in an electric field. Therefore, a liquid crystal display device has a liquid crystal panel composed of a pair of transparent insulating substrates each having an electric field generating electrode formed on the surfaces facing each other with a liquid crystal layer in between, as an essential component, and between the electric field generating electrodes. The alignment direction of the liquid crystal molecules is artificially adjusted by changing the electric field, and various images are displayed using the light transmittance that changes at this time.

  At this time, polarizing plates for visualizing the change in the liquid crystal alignment of the liquid crystal display device are respectively disposed at the upper and lower portions of the liquid crystal panel, and the polarizing plate transmits light having a polarization component that matches the transmission side. The degree of light transmission is determined by the arrangement of the transmission axis and the alignment characteristics of the liquid crystal.

  FIG. 1 schematically shows a general polarizing plate. As shown in the drawing, the polarizing plate 1 is formed with a polarizing layer 2 having a polarization axis that changes the polarization characteristics of light and is manufactured by stretching PVA (polyvinyl alcohol) that absorbs iodine, which is a polarizer, with a strong tension, First and second TAC films (triacetate cellulose films: 3 and 4) formed on both sides of the polarizing layer 2 to protect and support the polarizing layer 2, and one side of the first TAC film 3 (on the polarizing layer 2 side) A protective film 5 that prevents the surface of the polarizing plate 1 from being damaged, and is formed on one side of the second TAC film 4 (on the side opposite to the polarizing layer 2 side) via an adhesive 6. The release film 7 is made of.

  As shown in FIG. 2, such a polarizing plate 1 is prepared after preparing a raw material roll on which a PVA film, a TAC film (first TAC film and second TAC film), a protective film and a release film are wound (FIG. 2). A), after passing through a pretreatment process in which the raw material roll is washed in a washing tank and dried in a drying oven (b in FIG. 2), the first TAC film and the second TAC film are laminated on both sides of the PVA film, After stretching the film to form an intermediate roll (c in FIG. 2), a protective film is laminated on the surface of the first TAC film, while a release film is laminated on the surface of the second TAC film with an adhesive. After forming the polarizing plate roll (d in FIG. 2), after cutting with a punch according to size with a cutting press (e in FIG. 2), the step of inspecting and packaging (in FIG. 2) ) By the completion of manufacture.

  If the manufacturing process of the conventional polarizing plate is explained based on a block diagram, as shown in FIG. 3, raw materials such as a PVA film, a first TAC film, a second TAC film, a protective film and a release film are prepared, washed and dried. After the pretreatment step (S1) to be performed, the first TAC film is laminated on one surface of the PVA film, the second TAC film is laminated on the other surface of the PVA film, and the stretching step (S2). )I do. Then, after passing through this stretching step (S2), a protective film is laminated on the surface of the first TAC film, while a pressure sensitive adhesive is coated on the surface of the second TAC film and a release film is laminated (S3). )I do. And after passing through this coating and laminating process (S3), the punch cutting process (S4) which cuts with a punch according to the size of a polarizing plate in a cutting press is performed. Then, after this punch cutting step (S4), a chamfering step (S5) for processing (milling) the edge of each of the cut polarizing plates is performed. After this chamfering step (S5), an inspection step (S6) for inspecting each polarizing plate with the naked eye is performed. And after passing through this inspection process (S6), the packaging process (S7) which packages each product with a pack (pack) is performed, and the product is shipped through this packaging process (S7).

  In the punch cutting process (S4), since the edge is chamfered in the chamfering process, the cutting size is cut larger than the final part.

  However, in the process of manufacturing a conventional polarizing plate, the polarizing plate is cut with a punch, so a chamfering process for processing the cut surface is necessary, and each product is inspected with the naked eye after the chamfering process. Therefore, there is a problem that the manufacturing time and cost are high.

  Accordingly, the present invention has been derived in order to solve the above-described problems, and an object of the present invention is to provide a method for manufacturing a polarizing plate that simplifies the cutting and inspection of the polarizing plate and reduces the manufacturing cost. There is.

  Another object of the present invention is to improve the quality of the cut surface of the polarizing plate by changing the angle of the polarizing component so that it is inclined at a predetermined angle with respect to the crystal lattice arrangement direction of the polarizing plate, and to improve the uniformity of the polarizing plate. It is providing the manufacturing method of the polarizing plate which raises.

  The manufacturing method of the polarizing plate according to the present invention for achieving the above object includes a pretreatment process in which a PVA film, first and second TAC films, a protective film and a release film are prepared, washed and dried, and the PVA film. The first TAC film is laminated on one side of the PVA film, the second TAC film is laminated on the other side of the PVA film, while the stretching step of stretching the PVA film, and the protective film is laminated on the surface of the first TAC film, A coating and laminating process for coating the surface of the second TAC film and laminating a release film, an inspecting process for inspecting the polarizing plate after coating and laminating, and cutting the polarizing plate after the inspection with a laser. Laser cutting process that cuts into individual parts and parts cut with laser Characterized in that comprising a packaging step of packaging.

  The laser cutting step includes a laser slit step of cutting the polarizing plate in a direction parallel to the crystal lattice arrangement direction, and a polarizing plate cut in the laser slit step in a direction orthogonal to the crystal lattice arrangement direction. It consists of a laser cutting process of cutting and cutting.

  The laser cutting step includes cutting a polarizing plate in a direction orthogonal to the crystal lattice arrangement direction, and cutting the polarizing plate cut in the laser cutting step in parallel to the crystal lattice arrangement direction. It can also consist of a laser slit process which cuts in the direction to do.

  In the inspection step, the polarizing plate is automatically inspected, while the portion to be cut in the laser cutting step is marked to perform a defective marking inspection.

  The defective marking inspection may be performed before the laser cutting step of the laser cutting step.

  In the laser cutting step, a linear polarization component arranged so as to be orthogonal or parallel to the cutting direction of the polarizing plate when the laser beam is output from the laser supply source is converted into a crystal lattice of the polarizing plate by a polarization adjusting unit. The polarizing plate is cut so as to be inclined by the polarization rotation angle with respect to the arrangement direction.

  The laser cutting step includes a laser slit step for cutting the polarizing plate in a direction parallel to the crystal lattice arrangement direction (transfer traveling direction), and the polarizing plate cut in the laser slit step with respect to the crystal lattice arrangement direction. It is preferable to perform the cutting with the polarization rotation angle α changed by the polarization adjusting unit within a range of ± 30 ° to 60 °.

  The laser cutting step includes a laser cutting step of cutting the polarizing plate in a direction orthogonal to the crystal lattice arrangement direction, and a polarizing plate cut in the laser cutting step in a direction parallel to the crystal lattice arrangement direction. Although it consists of a laser slit process for cutting, the polarization rotation angle α changed by the polarization adjusting section can be cut within a range of ± 30 ° to 60 °.

  According to the method for manufacturing a polarizing plate according to the present invention, the polarizing plate is automatically inspected, marked, and cut with a laser, so that the chamfering process can be omitted and packaging can be performed immediately after laser cutting. It has the effect of reducing costs and manufacturing costs.

  Further, by changing the angle of the polarization component so as to be inclined at a predetermined angle with respect to the crystal lattice arrangement direction of the polarizing plate, there is an effect of improving the quality of the cut surface of the polarizing plate and increasing the uniformity of the polarizing plate.

It is a figure which shows a general polarizing plate roughly. It is a figure which shows the manufacturing process of a general polarizing plate. It is process drawing which shows the manufacturing method of the conventional polarizing plate. It is process drawing which shows the manufacturing method of the polarizing plate to which this invention was applied. It is the schematic which shows one Example of the RTS laser cutting machine used for the manufacturing method of the polarizing plate by this invention. It is the schematic which shows the other Example of the RTS laser cutting machine used for the manufacturing method of the polarizing plate by this invention. It is a schematic perspective view which shows the Example of the laser cutter part of the RTS laser cutting machine of FIG. 5 or FIG. FIG. 8 is a partial detailed perspective view showing in detail the polarization adjusting unit shown in FIG. 7. FIG. 9 is a perspective view illustrating in detail a correlation between a polarization adjusting unit and a laser beam illustrated in FIG. 8. It is a perspective view which expands and shows a linearly polarized light component of a condensing head, a polarizing plate, and a laser beam. It is a perspective view which expands and shows a linearly polarized light component of a condensing head, a polarizing plate, and a laser beam. It is a figure of the comparative example which shows the state by which a polarizing plate is cut | disconnected in the state in which the arrangement direction of a crystal lattice is orthogonal to the polarization component of a laser beam with the laser beam irradiated at a laser cutting process. It is a top view photograph which shows the cut surface of the polarizing plate cut | disconnected in the state of FIG. It is a cross-sectional photograph which expands and shows the cut surface of the polarizing plate shown in FIG. It is a plane photograph which shows the cut surface of the polarizing plate cut | disconnected with the laser beam which the polarized light component irradiated at the laser cutting process by the Example of this invention inclined 45 degrees. It is a cross-sectional photograph which expands and shows the cut surface of the polarizing plate shown in FIG. It is a plane photograph which shows the cut surface of the polarizing plate cut | disconnected by the laser beam in which the polarization component irradiated by the laser cutting process by the Example of this invention inclines 60 degrees. It is a plane photograph which shows the cut surface of the film cut | disconnected by the laser beam in which the polarization component irradiated by the laser cutting process by the Example of this invention inclined 70 degrees.

  Hereinafter, embodiments of the present invention will be described in more detail with reference to the accompanying drawings.

  FIG. 4 is a process block diagram of a method for manufacturing a polarizing plate according to the present invention. As shown in the drawing, the manufacturing process of the polarizing plate includes a pretreatment process (S10) in which a PVA film, a first and second TAC film, a protective film, and a release film are prepared, washed and dried, and one of the PVA films. While laminating the first TAC film on the surface and laminating the second TAC film on the other surface of the PVA film, while stretching the PVA film (S20), while laminating a protective film on the surface of the first TAC film, The coating and laminating step (S30) for coating the surface of the second TAC film with an adhesive and laminating the release film, the inspection step (S40) for inspecting the polarizing plate after coating and laminating, and the inspection are completed. Laser cutting step (S5) ) And, consisting of a packaging step of packaging the parts cut with a laser (S70).

  In the present embodiment, the polarizing plate being manufactured is once unwound from the state of being wound on a roll as in the prior art, and then taken up again and transferred by a conveyor and a support roll, and the operations of each step are performed. One or three steps can be performed continuously, or the entire process can be performed continuously.

  The pretreatment step (S10), the stretching step (S20), and the coating and laminating step (S30) are the same as the conventional method for producing a polarizing plate. In the coating and laminating process (S30), the coating process and the laminating process may be performed separately.

  The inspection step (S40) is a step of automatically inspecting the polarizing plate with an automatic inspection device, marking the portion to be cut in the laser cutting step (S50), and classifying defective products and non-defective products with a laser cutting machine to be described later. Make sure that cutting is done.

  The laser cutting step (S50) includes a laser slit step (S52) for cutting the polarizing plate in a direction parallel to the crystal lattice arrangement direction (transfer traveling direction) and the polarized light cut in the laser slit step (S52). A laser cutting step (S54) for cutting the plate in a direction perpendicular to the crystal lattice arrangement direction.

  The laser slitting step (S52) and the laser cutting step (S54) may be performed by a separate laser cutting machine and cutting machine, or may be performed by a single laser cutting machine.

  In this embodiment, the laser cutting process (S54) and the packaging process (S70) are performed using one RTS (Roll To Sheet) laser cutting machine. In the laser slit process (S52), slitting is performed with a separate laser cutting machine. The defect marking inspection in the inspection step (S40) is performed before the laser cutting step (S54) with the RTS cutter.

  FIG. 5 is a schematic view showing an embodiment of an RTS laser cutting machine applied to the present invention. As illustrated, the RTS laser cutting machine 60 includes a rewinding unit (61: unwinding unit) on which a roll wound with a polarizing plate that has undergone a laser slitting process (S52: shown in FIG. 4) is applied, A dancer unit (62: dancer unit) that controls the constant tension when moving, and an infeed unit that determines the size accuracy in the direction of travel by supplying the polarizing plate at a fixed speed. 63: infeed unit), a marking inspection part 64 to which a camera sensor is attached so as to recognize and inspect whether there is a defective marking in the part marked in the inspection step (S40: shown in FIG. 4), and along the marking line A laser cutter unit 65 for cutting the polarizing plate in the width direction, a conveyor 66 for transferring the cut polarizing plate, and the conveyor 66 It consists feed polarizing plates packaging conveyor 67 for packaging placed into a packaging container.

  The laser cutter 65 is a part that cuts using a laser beam generated from a carbon dioxide laser head, and the laser-cut polarizing plate is transferred via a conveyor 66 and a packaging conveyor 67 and immediately packaged. Therefore, the conventional separate chamfering process and the inspection process after the chamfering process are unnecessary.

  FIG. 6 is a schematic view showing another embodiment of the RTS laser cutting machine applied to the present invention. As illustrated, the RTS laser cutting machine 160 includes a rewinding unit (161: unwinding unit) on which a roll wound with a polarizing plate that has undergone a laser slit process (S52: shown in FIG. 4) is applied, A dancer unit (162: dancer unit) that controls constant tension during movement, and a feed unit (163) that plays a role of supplying a polarizing plate at a predetermined speed and determining size accuracy in the traveling direction. : Feed unit), a marking inspection unit 164 for recognizing and inspecting the presence or absence of defective marking in the portion marked in the inspection step (S40: displayed in FIG. 4), and cutting the polarizing plate in the width direction along the marking line A laser cutter unit 165, a measuring unit 166 that measures squareness and size in real time just before cutting using a camera, and a laser -Laser conveyor 167 for adsorbing and fixing the polarizing plate during cutting, tilting conveyer 168 for discharging cutting scrap (Scrap) of defective marking after laser cutting, and conveyor (169 for transferring the cut polarizing plate) -1), a polarizing plate transport section (169-2) for automatically transferring the cut polarizing plates one by one, and a box-type packaging container placed in the rear part of the conveyor (169-1), and cutting A polarizing plate stacking portion (169-3) for immediately packaging the polarizing plate.

  That is, in the laser cutting step (S54) using the RTS laser cutting machine (FIG. 6) of the present embodiment, the perpendicularity and size of the polarizing plate are measured in real time immediately before cutting using a camera, and cutting is performed. After the laser cutting step (S54), the cutting scrap (Scrap) of the defective marking portion of the polarizing plate is discharged through the tilting conveyor 168, and in the packaging step (S70), the conveyor for transferring the cut polarizing plate. Place the carriage (or box-type packaging container) in the rear part of (169-1) and wrap it immediately, or place the cut polarizing plate in the carriage (or box-type packaging container) and polarizing plate Is it a carriage on the polarizing plate attachment line by transferring it to the attachment line? It was transferred the product will be used to adhere machine magazine.

  As shown in FIGS. 7 and 8, the laser cutter unit (65, 165) of the RTS laser cutter (60, 160) used in the polarizing plate manufacturing method of the present invention includes a support frame 103, a laser beam supply source 105, It comprises a condensing head 107, a polarization adjusting unit 109, and a laser beam transmission unit 111.

  Here, the support frame 103 forms an outer body of the laser cutter unit (65, 165), and is on the process line as a part of the entire process of processing the polarizing plate 110 cut by the laser cutter unit (65, 165). Placed in.

  Therefore, in the embodiment shown in FIG. 7, the polarizing plate 110 is put into the support frame 103 through the transfer means 113 such as a conveyor belt installed along the entire process line, thereby supporting the plate. The polarizing plate 110 is cut by the laser beam (B) irradiated from the condensing head 107 installed on the upper stage side of the frame 103.

  The laser beam supply source 105 is a portion that generates a laser beam (B) used for cutting the polarizing plate 110 and supplies the laser beam (B) to the condensing head 107, and is attached to one side of the upper stage of the support frame 103. It may be attached so as not to move to one side of the upper plate 112 of the support frame 103, or may be movably attached together with the upper plate 112. Since the internal configuration of the laser beam supply source 105 is the same as that of a general laser generator, a detailed description related to the internal configuration is omitted.

  The condensing head 107 is means for irradiating the polarizing plate 110 with the laser beam (B) transmitted from the laser beam supply source 105 and cutting it, and is fixed to the front side surface of the upper plate 112. Alternatively, the polarizing plate 110 is cut by moving together with the upper plate 112 or movably with respect to the upper plate 112.

  The polarization adjustment unit 109 is a part that changes the angle of the linearly polarized component of the laser beam (B) output from the laser beam supply source 105. As shown in FIGS. 7 to 9, the laser beam supply source Preferably, it is attached adjacent to the output side of the laser beam supply source 105 so as to be positioned between the laser beam source 105 and the condenser head 107. The polarization adjusting unit 109 sets the angle of the linearly polarized component (P) of the laser beam (B) output from the laser beam supply source 105 in a vertical state as shown in FIGS. 8 and 9, for example. A predetermined polarization rotation angle α is inclined with respect to the perpendicular.

  At this time, the polarization rotation angle α is a linear polarization component (P) of the laser beam (B) arranged so as to be orthogonal or parallel to the cutting direction of the polarizing plate 110 that is cut while moving relative to the condensing head 107. ) Is an angle inclined with respect to the crystal lattice (L) arrangement direction of the polarizing plate 110 and is preferably within a range of ± 30 ° to 60 °, and ± 45 ° as shown in FIGS. It is more preferable to tilt only.

  As shown in the comparative example of FIG. 12, the condensing head 107 relatively moves in a state in which the linearly polarized light component (P) is orthogonal to the crystal lattice (L) arrangement direction of the polarizing plate 110 that is the object to be cut. When the polarizing plate 110 is cut by the laser beam (B) irradiated from the condensing head 107, there is a problem that the quality of the cut surface becomes poor as shown in FIGS. Accordingly, when a removing tape is attached to the film protective layer in order to remove the film protective layer (protective film) attached to the outermost layer of the polarizing plate after the laser cutting step, as shown in FIG. Since the surface is not uniform, the removing tape is not reliably attached to the polarizing plate 110, and as a result, the film protective layer is not accurately removed.

  However, by tilting the linearly polarized component of the laser beam to 45 ° with respect to the crystal lattice arrangement direction of the polarizing plate, as shown in FIGS. 15 and 16 (Example of the present invention), the quality of the cut surface of the polarizing plate is shown. In particular, when the polarization rotation angle is 45 °, it is not necessary to check whether the crystal lattice arrangement direction of the polarizing plate is perpendicular or parallel to the cutting direction by the laser beam. The quality of the cut surface can be greatly improved.

  Further, not only the cut surface but also the polarizing plate surface layer adjacent to the cut surface is maintained uniformly as shown in FIG. For this reason, especially in the case of a polarizing plate having a laminated structure, when attaching a removal tape on the protective film to peel off the protective film forming the surface layer, the protective film and the tape are in close contact with each other. The protective layer can be removed with certainty and smoothness later, and the process efficiency is improved.

  The quality of the cut surface depends on the angle at which the linearly polarized light component is tilted. However, when the polarization rotation angle α is 45 °, the quality of the cut surface is the best as shown in FIG. When the angle is 60 ° or 60 °, it is within the allowable range as shown in FIG. 17, but when it is 30 ° or less or 60 ° or more, it is as in the case of 70 ° shown in FIG. When the angle is 90 °, the worst state is obtained as shown in FIG.

  On the other hand, as shown in FIG. 7, the polarization adjusting unit 109 can not only use an existing polarization adjusting device sold in a module form, but also can be manufactured as one optical system as shown in FIGS. At this time, the polarization adjusting unit 109 includes a main reflecting mirror 109a, an auxiliary reflecting mirror 109b, and a support bar 109c for supporting them.

  The main reflecting mirror 109a is installed adjacent to the exit side of the laser beam (B) of the laser beam supply source 105, and the laser beam (B) output from the laser beam supply source 105 is changed by a polarization rotation angle α. At this time, the rotation of the laser beam (B) is the same as that of the coordinate plane (C) so as not to leave the coordinate plane (C) formed by the laser beam (B) and the linearly polarized light component (P). Should be done on the plane.

  The auxiliary reflecting mirror 109b is installed adjacent to the periphery of the main reflecting mirror 109a, and the laser beam (B) reflected by the main reflecting mirror 109a at a predetermined polarization rotation angle α is applied to the coordinate plane (C). It arrange | positions on a coordinate plane (C) so that it may reflect in the orthogonal direction.

  As shown in FIGS. 7 to 9, the laser beam transmission unit 111 outputs a laser beam (B) having a tilted polarization component output from the polarization adjusting unit 109, that is, reflected from the auxiliary reflecting mirror 109b. ) To the condensing head 107, and for this purpose, between the laser beam supply source 105 and the condensing head 107, that is, between the polarization adjusting unit 109 and the condensing head 107. Several are installed in between.

  The laser cutting step (S50) is a step of cutting the polarizing plate 110 put into the cutting position with the laser beam (B). As shown in FIG. 7, the polarizing plate 110 is aligned with the crystal lattice (L) arrangement direction. The linearly polarized component (P) of the laser beam (B) arranged so as to be orthogonal or parallel to the cutting direction of the polarizing plate 110 at the time of output from the laser source 105. ) Is inclined by a polarization rotation angle α with respect to the crystal lattice (L) arrangement direction of the polarizing plate 110 by the polarization adjusting unit 109. Therefore, as shown in FIGS. 8 and 9, the laser beam (B) output from the laser source 105 is on a coordinate plane (C) formed by the laser beam (B) and the linearly polarized component (P). The linear reflection component (P) of the laser beam (B) reflected by the main reflection mirror 109a after being rotated by, for example, a polarization rotation angle α of 45 ° is reflected by the polarization rotation angle with respect to the vertical line. Tilt by α. For this purpose, the main reflecting mirror 109a is arranged so as to be inclined by the polarization rotation angle α with respect to the horizontal line.

  Next, the laser beam (B) reflected by the main reflecting mirror 109a is reflected again by the auxiliary reflecting mirror 109b and bent in a direction perpendicular to the coordinate plane (C). As a result, the linearly polarized light component (P) is inclined by the polarization rotation angle α with respect to the vertical line as shown in FIG.

  In this way, the laser beam (B) in which the polarization component (P) is tilted at the polarization rotation angle α is a laser beam transmission unit composed of one or more reflecting mirrors as shown in FIGS. The polarization component (P) is reflected through 111 and reaches the condensing head 107. When the polarizing plate 110 is irradiated from the condensing head 107, the polarization component (P) is a polarization rotation angle with respect to the cutting direction of the polarizing plate 110. It becomes inclined only by α. Therefore, ± α with respect to the crystal lattice (L) arrangement direction of the polarizing plate 110, that is, + α when the crystal lattice (L) is arranged at right angles to the cutting direction as shown in FIG. When arranged so as to be parallel to the cutting direction as shown in FIG.

  In the case where the laser cutting step (S50) includes a laser slit step (S52) and a laser cutting step (S54), in the laser slit step (S52), the stretched polarizing plate 110 is elongated by stretching. While cutting in the length direction of (L), that is, in a direction parallel to the crystal lattice (L) arrangement direction, in the laser cutting step (S54), in the laser slit step (S52), the crystal lattice ( L) The polarizing plate 110 cut so as to be parallel to the arrangement direction is cut in a direction orthogonal to the crystal lattice (L) arrangement direction.

  On the other hand, in the laser cutting step (S50), although the polarizing plate 110 is not shown separately, the laser cutting step (S54) can be performed before the laser slit step (S52). In the cutting step (S54), the polarizing plate 110 is first cut in a direction orthogonal to the crystal lattice (L) arrangement direction, and the polarizing plate 110 cut in the laser cutting step (S54) is cut into the next laser slit step. In (S52), the cutting may be performed in a direction parallel to the crystal lattice (L) arrangement direction.

  Although the present invention has been described with reference to the embodiments shown in the drawings, this is by way of example only, and various modifications and other equivalent implementations will occur to those of ordinary skill in the art. It goes without saying that examples are possible, and the technical protection scope of the present invention should be determined by the technical idea of the appended claims.

Claims (10)

A pretreatment step of preparing a PVA film, a first and second TAC film, a protective film and a release film, washing and drying;
A first TAC film is laminated on one surface of the PVA film, and a second TAC film is laminated on the other surface of the PVA film, while a stretching step of stretching the PVA film;
A coating and laminating step of laminating a protective film on the surface of the first TAC film, and coating an adhesive on the surface of the second TAC film and laminating a release film;
An inspection process for inspecting the polarizing plate after coating and laminating;
A laser cutting step of cutting the polarizing plate after inspection with a laser,
A packaging process for packaging the laser-cut parts,
In the laser cutting step, a linear polarization component arranged so as to be orthogonal or parallel to the cutting direction of the polarizing plate when the laser beam is output from the laser supply source is converted into a crystal lattice of the polarizing plate by a polarization adjusting unit. A method for producing a polarizing plate, wherein the polarizing plate is cut so as to be inclined by a polarization rotation angle with respect to the arrangement direction. The laser cutting step
A laser slit process for cutting the polarizing plate in a direction parallel to the crystal lattice arrangement direction;
The manufacturing method of a polarizing plate according to claim 1, comprising: a laser cutting step of cutting the polarizing plate cut in the laser slit step in a direction orthogonal to the crystal lattice arrangement direction. Method. The laser cutting step
A laser cutting step of cutting and cutting the polarizing plate in a direction perpendicular to the crystal lattice arrangement direction;
The method for producing a polarizing plate according to claim 1, comprising a laser slit step of cutting the polarizing plate cut in the laser cutting step in a direction parallel to the crystal lattice arrangement direction.   In the said inspection process, while inspecting a polarizing plate automatically, the part cut | judged by the said laser cutting process is marked, and defective marking inspection is performed, The any one of Claims 1-3 characterized by the above-mentioned. The manufacturing method of the polarizing plate of description.   The method for manufacturing a polarizing plate according to claim 4, wherein the defective marking inspection is performed before a laser cutting step of the laser cutting step.   4. The method for manufacturing a polarizing plate according to claim 2, wherein in the laser cutting step, the perpendicularity and size of the polarizing plate are measured in real time immediately before cutting.   6. The method of manufacturing a polarizing plate according to claim 5, wherein after the laser cutting step, cutting scrap of the defective marking portion is discharged.   The method for manufacturing a polarizing plate according to claim 1, wherein the packaging step immediately wraps the cut polarizing plate at a rear portion of a conveyor for transferring the polarizing plate. The laser cutting step includes a laser slit step of cutting the polarizing plate in a direction parallel to the crystal lattice arrangement direction, and a polarizing plate cut in the laser slit step in a direction orthogonal to the crystal lattice arrangement direction. It consists of a laser cutting process to cut,
The method for producing a polarizing plate according to claim 1, wherein the polarization rotation angle changed by the polarization adjusting unit is cut within a range of ± 30 ° to 60 °. The laser cutting step includes a laser cutting step of cutting the polarizing plate in a direction orthogonal to the crystal lattice arrangement direction, and a polarizing plate cut in the laser cutting step in a direction parallel to the crystal lattice arrangement direction. It consists of a laser slit process to cut,
The method for producing a polarizing plate according to claim 1, wherein the polarization rotation angle changed by the polarization adjusting unit is cut within a range of ± 30 ° to 60 °.