TWI676554B - Bonding tape, protective piece using the same and polarizing plate using the same - Google Patents

Abstract

A bonding tape, a protective sheet to which the adhesive tape is applied, and a polarizing plate. The protective sheet includes a first protective layer, a second protective layer, and a bonding tape. The second protective layer and the first protective layer are side by side. The adhesive tape joins the first protective layer and the second protective layer.

Description

Adhesive tape, protective sheet applied thereto, and polarizing plate

The present invention relates to a bonding tape, a protective sheet and a polarizing plate using the same, and particularly to a bonding tape capable of bonding two protective layers, a protective sheet and a polarizing plate using the same.

Traditionally, two protective sheets and polarized light can be laminated into a polarizing plate through a laminating device. However, the protective sheet needs to use adhesive during the manufacturing process. This adhesive will overflow during the lamination process and contaminate the lamination equipment, which will contaminate the polarizing plate or other types of optical products in subsequent processes. Therefore, how to improve the aforementioned pollution problem is one of the goals of those skilled in the art.

The invention relates to a bonding tape, a protective sheet and a polarizing plate using the same, which can improve the aforementioned pollution problem.

An embodiment of the invention provides a bonding tape. The bonding tape includes a substrate and a bonding layer. The substrate has a joint surface and a first substrate side and a second substrate side opposite to each other. The bonding layer is formed on the bonding surface of the substrate. The bonding layer is spaced a first distance from the side surface of the first substrate and a second distance from the side surface of the second substrate.

Another embodiment of the present invention provides a protective sheet. The protective sheet includes a first protective layer, a second protective layer, and the aforementioned bonding tape. The second protective layer and the first protective layer are side by side. The adhesive tape joins the first protective layer and the second protective layer side by side.

Another embodiment of the present invention provides a polarizing plate. The polarizing plate includes a first protective sheet, a second protective sheet, and a polarizing layer. The polarizing layer is disposed between the first protective sheet and the second protective sheet. At least one of the first protective sheet and the second protective sheet has the structure of the aforementioned protective sheet.

Another embodiment of the present invention provides a protective sheet. The protective sheet includes a first protective layer, a second protective layer, a bonding tape, and a cutting tape. The second protective layer and the first protective layer are side by side. The adhesive tape joins the first protective layer and the second protective layer side by side. The first protective layer has a surface treatment layer, a cutting tape is stuck on the other surface of the first protective layer opposite to the surface treatment layer, and the bonding tape covers the entire cutting tape.

Another embodiment of the present invention provides a polarizing plate. The polarizing plate includes a first protective sheet, a second protective sheet, and a polarizing layer. The polarizing layer is disposed between the first protective sheet and the second protective sheet. At least one of the first protective sheet and the second protective sheet has the structure of the aforementioned protective sheet.

In order to have a better understanding of the above and other aspects of the present invention, the following specific examples are described in detail below in conjunction with the accompanying drawings:

100, 200‧‧‧ polarizing plates

110, 210, 310, 410, 510, 610‧‧‧ first protective film

111‧‧‧first protective layer

111a, 112a ‧ ‧ first side

111b‧‧‧Second Side

111s‧‧‧ side of the first protective layer

112‧‧‧Second protective layer

112s‧‧‧Side of the second protective layer

113‧‧‧Joint tape

1111, 2141‧‧‧ substrate

1131a, 2141a ‧‧‧ joint surface

1131b, 2141b‧‧‧ side of the first substrate

1131c, 2141c‧‧‧Side of the second substrate

1131d‧‧‧side of the third substrate

1131e‧‧‧Four side substrate

1132, 2142‧‧‧ bonding layer

120, 220‧‧‧Second protective film

130‧‧‧polarizing layer

214‧‧‧cut tape

2142b‧‧‧ Side of the first bonding layer

2142c‧‧‧Side of the second bonding layer

215‧‧‧Surface treatment layer

A1‧‧‧ angle

S1‧‧‧First distance

S2‧‧‧Second Distance

S3‧‧‧ Distance

S4‧‧‧ Third distance

SP1, SP2 ‧‧‧ Adhesive Space

P1, P11 ~ P15‧‧‧ cutting road

FIG. 1A illustrates a top view of a first protective sheet according to an embodiment of the present invention.

FIG. 1B is a cross-sectional view of the first protective sheet in FIG. 1A along the direction 1B-1B '.

FIG. 2 is a cross-sectional view of a polarizing plate according to an embodiment of the present invention.

FIG. 3 is a cross-sectional view of a first protective sheet according to another embodiment of the present invention.

4A to 4D illustrate manufacturing process diagrams of the first protective sheet of FIG. 3.

FIG. 5 is a top view of a polarizing plate according to another embodiment of the present invention.

6 to 9 are schematic diagrams of protection sheets according to other embodiments of the present invention.

Please refer to FIGS. 1A and 1B. FIG. 1A illustrates a top view of the first protection sheet 110 according to an embodiment of the present invention, and FIG. 1B illustrates the first protection sheet 110 of FIG. 1A along the direction 1B-1B '. Sectional view.

The first protection sheet 110 includes a first protection layer 111, a second protection layer 112, and a bonding tape 113. The bonding tape 113 bonds the separated first protection layer 111 and the second protection layer 112 to form an extended protection layer structure. The first protection sheet 110 in this embodiment is, for example, a first protection sheet before being cut into at least one polarizer product, which has a certain continuous length, can be wound on a reel, and can be continuously transmitted in a lamination. Device.

The first protective layer 111 and the second protective layer 112 are arranged side by side. For example, the first protective layer 111 and the second protective layer 112 have a first protective layer side surface 111s and a second protective layer side surface 112s, respectively, and the first protective layer side surface 111s and the second protective layer side surface 112s are oppositely disposed. In addition, the first protective layer side surface 111s and the second protective layer side surface 112s may be in contact with each other, but may also be spaced apart from each other.

The adhesive tape 113 is adhered to the first surface 111a of the first protective layer 111 and the first surface 112a of the second protective layer 112 to bond the first protective layer 111 and the second protective layer. 112. The first surface 111 a of the first protective layer 111 and the first surface 112 a of the second protective layer 112 are surfaces on the same side of the first protective sheet 110.

The bonding tape 113 includes a base material 1131 and a bonding layer 1132. The bonding layer 1132 is formed in advance on the bonding surface 1131 a of the base material 1131. The bonding tape 113 bonds the first protective layer 111 and the second protective layer 112 through the bonding layer 1132. In addition, the bonding layer 1132 is, for example, an adhesive, which may be made of a material such as a (meth) acrylic copolymer, such as a material that may include, but is not limited to, a functional group, such as methyl (meth) acrylate, (meth) ) Ethyl acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate and the like.

The substrate 1131 further has a first substrate side surface 1131b and a second substrate side surface 1131c opposite to each other. The aforementioned bonding surface 1131a extends between the first substrate side surface 1131b and a second substrate side surface 1131c. The bonding layer 1132 is spaced a first distance S1 from the first substrate side surface 1131b and is spaced a second distance S2 from the second substrate side surface 1131c. In this way, in the lamination process of the polarizing plate 100 (as shown in FIG. 2), it is possible to prevent the adhesive of the bonding layer 1132 from overflowing beyond the first substrate side 1131 b and the second substrate side 1131 c under the action of the lamination force, and furthermore, Avoid contamination of the adhesive of the bonding layer 1132 to the pressing equipment, such as a roller.

The ratio of the sum of the first distance S1 and the second distance S2 to the distance S3 between the first substrate side surface 1131b and the second substrate side surface 1131c may be between about 2% to about 20%, or about 5% to about 20 % Or about 10% to about 20%, to ensure that the bonding layer 1132 does not overflow the first substrate side surface 1131b and the second substrate side surface 1131c.

In an embodiment, as shown in FIG. 1A, the third substrate side surface 1131d and the fourth substrate side surface 1131e of the bonding layer 1132 and the substrate 1131 which are opposite to each other may also There are designs similar to the first substrate side 1131b and the second substrate side 1131c to achieve similar effects.

Please refer to FIG. 2, which illustrates a cross-sectional view of a polarizing plate 100 according to an embodiment of the present invention. The polarizing plate 100 includes a first protective sheet 110, a second protective sheet 120, and a polarizing layer 130. The second protective sheet 120 has a structure that is the same as or similar to the first protective sheet 110, and details are not described herein again. The polarizing layer 130 is located between the first protective sheet 110 and the second protective sheet 120 to be protected by the first protective sheet 110 and the second protective sheet 120. In another embodiment, the second protection sheet 120 is a continuously extending single protection sheet structure, and may not include the bonding tape 113. The second protection sheet 120 in this embodiment is, for example, a second protection sheet before being cut into at least one polarizer product, which has a certain continuous length, can be wound on a reel, and can be continuously transferred to the lamination Device. In addition, the polarizing plate 100 in this embodiment is, for example, a polarizing plate before being cut into at least one polarizer product, which has a certain continuous length, can be wound on a reel, and can be continuously transmitted in a laminating device.

The polarizing layer 130 may be a polyvinyl alcohol (PVA) film that adsorbs and aligns dichroic pigments, or is formed by mixing liquid crystal material with absorbing dye molecules. Polyvinyl alcohol can be formed by saponifying polyvinyl acetate. In some embodiments, the polyvinyl acetate may be a single polymer of vinyl acetate or a copolymer of vinyl acetate and other monomers. The other monomers may be unsaturated carboxylic acids, olefins, unsaturated sulfonic acids, vinyl ethers, and the like. In other embodiments, the polyvinyl alcohol can be modified polyvinyl alcohol, for example, aldehyde-modified polyvinyl formaldehyde, polyvinyl acetaldehyde, or polyvinyl butyral, and the like.

In addition, after the polarizing plate 100 of FIG. 2 is formed, the polarizing plate 100 can be cut into at least one polarizer product, and the bonding tape 113 can be cut off. This polarizer product can be configured in a display device Set in. In other words, the bonding tape 113 will not remain on these polarizer products, and the bonding tape 113 can be prevented from affecting the optical effect of the polarizer products. As shown in the figure, the two-adhesive tape 113 is disposed oppositely, so that the two-adhesive tape 113 can be cut in the same cutting, and the cutting efficiency is improved. In another embodiment, the bonding tape 113 of the first protective sheet 110 and the bonding tape 113 of the second protective sheet 120 may be staggered in the length direction, and are not limited to be oppositely disposed.

Since the bonding layer 1132 is separated from the first substrate side surface 1131b by a first distance S1 (as shown in FIG. 1B) and is separated from the second substrate side surface 1131c by a second distance S2 (as shown in FIG. 1B) before the lamination, Therefore, after the polarizing layer 130, the first protective sheet 110, and the second protective sheet 120 are laminated, as shown in FIG. 2, the adhesive of the bonding layer 1132 does not overflow beyond the first substrate side 1131b and the second substrate side 1131c. . In this way, the glue of the bonding layer 1132 will not contaminate the rollers of the laminating equipment, and naturally will not contaminate any optical film subsequently transmitted on the rollers.

In an embodiment, as shown in FIG. 2, the bonding tape 113 of the first protective sheet 110 and the bonding tape 113 of the second protective sheet 120 are in direct contact with the polarizing layer 130, which can further prevent the adhesive of the bonding layer 1132 from overflowing and Contaminates the rollers of the laminating equipment and any subsequent optical films transmitted on the rollers.

Please refer to FIG. 3, which is a cross-sectional view of a first protection sheet 210 according to another embodiment of the present invention. The first protective sheet 210 includes a first protective layer 111, a second protective layer 112, a bonding tape 113, and a cutting tape 214. The cutting tape 214 is affixed to a cut protective layer having a surface treatment layer 215, such as the first protective layer 111. In one embodiment, the width of the cutting tape 214 may be between about 1.5 cm and about 3 cm, or between about 2 cm and about 2.5 cm.

In one embodiment, the surface treatment layer 215 is, for example, a hard coating layer, an anti-reflection layer, an anti-adhesion layer, a diffusion layer, or an anti-glare layer. Generally, the water contact angle of the surface treatment layer 215 can be between about 90 degrees and about 110 degrees.

In this embodiment, the first protective layer 111 has a surface treatment layer 215, so the surface hardness is high, so that the first protective layer 111 is not easy to be cut flat, and it is easy to generate a sawtooth-shaped cutting surface. In order to avoid foreign objects generated during cutting from affecting the environmental cleanliness of the production line, or polluting the rollers or transfer rollers of the laminating equipment, the cutting tape 214 is affixed before cutting the first protective layer 111 to avoid the above disadvantages.

In an embodiment, although the second protective layer 112 has a surface treatment layer 215, it is not cut, so the cutting tape 214 may not be affixed. However, the embodiment of the present invention is not limited thereto.

As shown in FIG. 3, the cutting tape 214 and the surface treatment layer 215 may be respectively formed on two different surfaces of the first protective layer 111. For example, the first protective layer 111 has a first surface 111a and a second surface 111b opposite to each other, a cutting tape 214 is stuck on the first surface 111a, and a surface treatment layer 215 is located on the second surface 111b.

The first protective layer 111 has a first protective layer side surface 111s. The cutting tape 214 includes a substrate 2141 and a bonding layer 2142, wherein the substrate 2141 has a bonding surface 2141a and opposite first substrate side 2141b and second substrate side 2141c, and the bonding surface 2141a extends on the first substrate side 2141b And the second substrate side surface 2141c, and the bonding layer 2142 has a first bonding layer side surface 2142b and a second bonding layer side surface 2142c opposite to each other. The first bonding layer side surface 2142b and the first substrate side surface 2141b together define a tape side surface of the cutting tape 214. Since the first protective layer side surface 111s, the first substrate side surface 2141b, and the first bonding layer side surface 2142b is formed in the same cut, so the first protective layer side surface 111s, the first substrate side surface 2141b, and the first bonding layer side surface 2142b can be roughly aligned. In addition, the material of the bonding layer 2142 is similar to that of the bonding layer 1132, and details are not described herein again.

As shown in FIG. 3, the bonding layer 2142 of the cutting tape 214 can be applied to the entire bonding surface 2141a, that is, the bonding layer 2142 can extend to the first substrate side 2141b and the second substrate side 2141c. In another embodiment, the bonding layer 2142 may be spaced apart from the first substrate side surface 2141b and / or the second substrate side surface 2141c. Since the second bonding layer side 2142c of the bonding layer 2142 of the cutting tape 214 is spaced a third distance S4 from the second substrate side 1131c of the substrate 1131, even if the bonding layer 2142 extends to the second substrate side 2141c, During the lamination process, the adhesive of the bonding layer 2142 does not overflow beyond the second substrate side surface 1131c of the substrate 1131, but is kept in the adhesive space SP1 between the second substrate side surface 2141c and the second substrate side surface 1131c. As such, the bonding layer 2142 does not contaminate the crimping equipment.

As shown in FIG. 3, since the bonding tape 113 protrudes beyond the first bonding layer side 2142 b of the bonding layer 2142 and is adhered to the second protective layer 112, the bonding tape 113, the second protective layer 112, and the substrate 2141 are formed. One plastic space SP2. In this way, even if the bonding layer 2142 extends to the side surface 2141b of the first substrate, the glue of the bonding layer 2142 will be kept in the glue-containing space SP2 in the subsequent pressing process without contaminating the pressing equipment.

Please refer to FIGS. 4A to 4D, which illustrate manufacturing processes of the first protective sheet 210 of FIG. 3.

As shown in FIG. 4A, a first protective layer 111 'is provided. The first protective layer 111 'has a first surface 111a and a second surface 111b opposite to each other, a cutting tape 214 is stuck on the first surface 111a, and a surface treatment layer 215 is formed on the second surface 111b. Cutting tape 214 includes a substrate 2141 and the bonding layer 2142, the cutting tape 214 is adhered to the first protective layer 111 'through the bonding layer 2142.

As shown in FIG. 4B, in a cutting process, a cutting path P1 is formed to cut off the first protective layer 111 'and the cutting tape 214 to form the first protective layer 111. After cutting, the first protective layer 111, the substrate 2141, and the bonding layer 2142 are respectively formed into a first protective layer side surface 111s, a first substrate side surface 2141b, and a first bonding layer side surface 2142b. In an embodiment, the cutting direction may be a direction from the first protective layer 111 'to the cutting tape 214, a direction from the cutting tape 214 to the first protective layer 111', or a direction perpendicular to the paper surface. Since the cutting tape 214 is pre-adhered to the first protective layer 111 'before cutting, during the process of cutting out the first protective layer 111, cutting chips generated by cutting to the surface treatment layer 215 can be reduced. In addition, the cutting tape 214 has the effect of sticking chips, which can reduce the number of chips detached from the first protective layer 111. The cutting path P1 is formed by using a punch, a cutting straight blade, a round blade, a laser, or scissors, for example.

As shown in FIG. 4C, a second protective layer 112 is provided. The first protective layer 111 and the second protective layer 112 are arranged side by side. For example, the first protective layer side 111s of the first protective layer 111 and the second protective layer side 112s of the second protective layer 112 are in contact with each other, but they may be spaced apart from each other. The second protective layer 112 may be a cut protective layer or an uncut protective layer. If the second protective layer 112 is a cut protective layer, another cutting tape 214 may be pre-adhered to the second protective layer 112, which is similar to the structure shown in FIG. 4B and will not be repeated here.

As shown in FIG. 4D, the first protective layer 111 and the second protective layer 112 are bonded side by side with a bonding tape 113, and the bonding tape 113 covers the entire cutting tape 214. In this way, even if the bonding layer 2142 is coated on the entire bonding surface 2141a of the substrate 2141, During the pressing process, the adhesive of the bonding layer 2142 overflows the first substrate side 2141b and the second substrate side 2141c of the substrate 2141, and is covered by the bonding tape 113 without contaminating the bonding equipment. As shown in the figure, after the bonding tape 113 is formed, the second substrate side surface 1131c of the bonding tape 113 and the second bonding layer side 2142c of the cutting tape 214 are separated by a third distance S4, so that the overflow of the bonding layer 2142 can be maintained. In the space SP1 of the third distance S4, the pressing equipment is not polluted. In addition, after the bonding tape 113 is formed, the bonding tape 113 protrudes beyond the first bonding layer side 2142b of the bonding layer 2142 and is stuck on the second protective layer 112, so that the bonding tape 113, the second protective layer 112, and the substrate 2141 are adhered to each other. The adhesive-containing space SP2 is formed, so that the overflowing glue of the bonding layer 2142 is kept in the adhesive-containing space SP2 without contaminating the pressing equipment.

Please refer to FIG. 5, which illustrates a top view of a polarizing plate 200 according to another embodiment of the present invention. The polarizing plate 200 includes a first protective sheet 210, a second protective sheet 220, and a polarizing layer 130. The polarizing layer 130 is located between the first protection sheet 210 and the second protection sheet 220 to be protected by the first protection sheet 210 and the second protection sheet 220. The polarizing plate 200 in this embodiment is, for example, a polarizing plate before being cut into at least one polarizer product, which has a certain continuous length, can be wound on a reel, and can be continuously transmitted in a laminating device.

As shown in FIG. 5, the cutting tape 214 is adhered to a protective sheet having a surface treatment layer 215, such as the first protective sheet 210. In addition, the second protective sheet 220 has a structure that is the same as or similar to the first protective sheet 210. The difference is that the protective layer of the second protective sheet 220 does not have a surface treatment layer 215. Therefore, the second protective sheet 220 may not include a cutting tape. 214. In another embodiment, if the protective layer (the first protective layer 111 and / or the second protective layer 112) of the second protective sheet 220 has a surface treatment layer 215, the second protective sheet 220 may further include another cutting tape. 214. In other embodiments, even The protective layer of the second protective sheet 220 does not have a surface treatment layer 215, and the second protective sheet 220 may optionally include another cutting tape 214. In addition, the second protective sheet 220 may be replaced by the aforementioned first protective sheet 110.

In addition, after the polarizing plate 200 of FIG. 5 is formed, the polarizing plate 200 can be cut into at least one polarizer product, and the bonding tape 113 and the cutting tape 214 can be cut out. In other words, the bonding tape 113 and the cutting tape 214 will not remain on these polarizer products, which can prevent the bonding tape 113 and the cutting tape 214 from affecting the optical effect of the polarizer products.

Please refer to FIG. 6 to FIG. 9, which are schematic diagrams of protection sheets according to other embodiments of the present invention. The structure of the protective sheet in Figs. 6 to 9 is similar to that of the aforementioned protective sheet, with the difference in the geometry of the cutting path.

As shown in FIG. 6, the protective sheet 310 includes a cutting tape 214, a bonding tape 113, and a first protective layer 111 and a second protective layer 112 that are connected to each other. The cutting tape 214 is adhered to the first protective layer 111 and is bonded. The adhesive tape 113 is attached to the cutting adhesive tape 214 and the second protective layer 112 to bond the first protective layer 111 and the second protective layer 112. Compared to the straight-cut cutting path P1 in FIG. 4B, the cutting path P1 in FIG. 6 is a bevel-cut type. The protective sheet 410 in FIG. 7 is similar to the protective sheet 310 in FIG. 6, except that the protective sheet 410 includes a two-section oblique cutting path P1. The angle A1 between the two-section cutting path P1 may be an acute angle or Obtuse angle. The protective sheet 510 of FIG. 8 is similar to the protective sheet 310 of FIG. 7, except that the cutting path of the protective sheet 510 is a larger number of segmented cutting paths. For example, the protective film 510 includes five cutting lanes P11 to P15, where the cutting lanes P11, P13, and P15 extend in the same direction, and the cutting lanes P12 and P14 extend in different directions, wherein the cutting lane P12 connects the cutting Road P11 and P13, and the cut road P14 connects the cut Cut through P13 and P15. The protective sheet 610 in FIG. 9 is similar to the protective sheet 310 in FIG. 6, except that the cutting path P1 of the protective sheet 610 is curved.

As can be seen in Figures 6-9, the number and geometry of the cutting paths can determine the geometry of the side of the protective layer. For example, when the cutting path is straight, the side of the protective layer that is cut is flat; when the cutting path is curved, the side of the protective layer that is cut is curved; when the cutting path is a multi-phase phase line , The side of the protective layer cut out is a multi-section abutting surface. The present invention does not limit the geometry of the cutting path, which may extend along a straight line, a curve, or a combination thereof.

In addition, as shown in FIGS. 6 to 9, the first protective layer 111, the base material 2141, and the bonding layer 2142 are cut to form the first protective layer side surface 111s, the first base material side surface 2141 b, and the first bonding layer side surface, respectively. 2142b. Since the first protective layer side surface 111s, the first substrate side surface 2141b, and the first bonding layer side surface 2142b are formed in the same cut, these side surfaces are aligned with each other.

In summary, the protective sheet according to the embodiment of the present invention includes two protective layers and a bonding tape, wherein the two protective layers are joined by an adhesive tape to form an extended protective layer structure to increase the continuity of the lamination process (if the length of the protective sheet is insufficient, the manufacturing process Need to stop frequently to replace with new protection sheet). In one embodiment, the bonding tape includes a substrate and a bonding layer. Since the bonding layer and the substrate side of the substrate are spaced apart from each other, during the pressing process, the glue of the bonding layer does not protrude beyond the side of the substrate and contaminates the pressing equipment. In another embodiment, the protective sheet includes two protective layers, a cutting tape and a bonding tape. The cutting tape is pre-adhered on the protective layer having a surface treatment layer and needs to be cut, so as to reduce chipping generated when the protective layer is cut out. The adhesive tape is stuck on the cutting tape and another protective layer to join the two protective layers. In one embodiment, since the bonding tape covers the entire cutting tape, the adhesive of the cutting tape can be prevented from being contaminated to the press. 合 设备。 Equipment. In addition, the polarizing plate and the protective sheet according to the embodiment of the present invention are, for example, a roll material before being cut into at least one polarizer product. Device.

In summary, although the present invention has been disclosed as above with the embodiments, it is not intended to limit the present invention. Those with ordinary knowledge in the technical field to which the present invention pertains can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be determined by the scope of the attached patent application.

Claims (10)

A protective sheet includes: a first protective layer having a surface treatment layer; a second protective layer side-by-side with the first protective layer; and a bonding tape bonded to the first protective layer side by side And the second protective layer, the bonding tape includes: a substrate having a bonding surface, a first substrate side and a second substrate side opposite to each other, a third substrate side and a fourth opposite side A side surface of the substrate; and a bonding layer formed on the bonding surface of the substrate, wherein the bonding layer is spaced a first distance from the side surface of the first substrate and a distance from the first The two substrate sides are spaced a second distance apart, and along the width direction of the first protective layer, the bonding layer is spaced a third distance from the third substrate side and a fourth distance away from the fourth substrate side. The protection sheet according to item 1 of the scope of patent application, wherein the ratio of the sum of the first distance and the second distance to the distance between the side surface of the first substrate and the side surface of the second substrate is between 2% ~ 20%. The protection sheet according to item 1 of the patent application scope, wherein the protection sheet is a protection sheet before being cut into at least one polarizer product, the protection sheet has a certain continuous length, and the protection sheet is used to be wound on a The winding wheel is continuously conveyed in a pressing device. The protective sheet according to item 1 of the scope of patent application, wherein the first protective layer and the second protective layer have a first protective layer side and a second protective layer side, respectively, the first protective layer side and the first protective layer side. The two protective layer sides are oppositely disposed, and the first protective layer side and the second protective layer side are in contact with each other or spaced from each other. The protective sheet according to item 1 of the scope of patent application, wherein the material of the bonding layer comprises methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, and (meth) acrylic acid 2 -Ethylhexyl ester. A polarizing plate includes: a first protective sheet; a second protective sheet; and a polarizing layer disposed between the first protective sheet and the second protective sheet; wherein the first protective sheet and the second protective sheet At least one of the protective sheets has the structure of the protective sheet described in item 1 of the scope of patent application. The polarizing plate according to item 6 of the scope of patent application, wherein the bonding tape of the first protective sheet and / or the second protective sheet is in direct contact with the polarizing layer. The polarizing plate according to item 6 of the patent application scope, wherein the polarizing plate is a protective sheet before being cut into at least one polarizer product, the polarizing plate has a certain continuous length, and the polarizing plate is used to be wound on a The winding wheel is continuously conveyed in a pressing device. The polarizing plate as described in item 6 of the scope of the patent application, wherein the polarizing layer is a polyvinyl alcohol (PVA) film that adsorbs and aligns dichroic pigments or is formed by mixing liquid crystal material with absorbing dye molecules. The polarizing plate according to item 6 of the patent application, wherein the first protective sheet and the second protective sheet both have the structure of the protective sheet described in item 1 of the patent application, and the bonding of the first protective sheet The adhesive tape is disposed opposite to the bonding tape of the second protective sheet or staggered along the length direction.