CN113703085A

CN113703085A - Polarizing plate structure, method for manufacturing same, method for evaluating same, and display device

Info

Publication number: CN113703085A
Application number: CN202110917116.1A
Authority: CN
Inventors: 徐维廷
Original assignee: Sumika Technology Co Ltd
Current assignee: Sumika Technology Co Ltd
Priority date: 2021-02-20
Filing date: 2021-08-11
Publication date: 2021-11-26
Anticipated expiration: 2041-08-11
Also published as: TWI755283B; TW202234097A; CN113703085B

Abstract

A polarizing plate structure and its manufacturing method and evaluation method, and a display device, the polarizing plate structure includes a polarizing plate composite layer, a first adhesive layer and a first covering layer, wherein the polarizing plate composite layer includes a polarizer and A first protective layer on the first surface of the polarizer, and the first protective layer has a rough surface away from the polarizer. The maximum surface roughness of the rough surface of the first protective layer is in the range of 0.45 μm to 5.1 μm. Furthermore, the first adhesive layer is located on the rough surface of the first protective layer, and the first cover layer is located on the first adhesive layer.

Description

Polarizing plate structure, method for manufacturing same, method for evaluating same, and display device

Technical Field

The present invention relates to a polarizer structure, a method for manufacturing the polarizer structure, a method for evaluating the polarizer structure, and a display device comprising the polarizer structure, and more particularly, to a polarizer structure comprising a protective layer having a rough surface, a method for manufacturing the polarizer structure, a method for evaluating the polarizer structure, and a display device comprising the polarizer structure.

Background

Public Information Displays (PID) can generally be divided into two displays for indoor use (e.g. Public transportation carriages, Information signs) and outdoor use (e.g. store street signs, open advertising signs).

The polarizer material of the display device is generally designed in consideration of the usage environment. In the case of public information displays, since the environment of use is different from the past consumer electronics market, in addition to the need to consider a material with better weather resistance in the selection of materials, there is also a need for improvement in the visibility of the display. For example, the outdoor ambient light source is strong, external light is reflected by the surface of the polarizing plate of the display, and glare is easily generated, resulting in a problem of poor visibility. Moreover, after the common information display with touch function is placed in a housing with a glass cover plate, the surface of the polarizer of the display is attracted to the glass cover plate to generate newton rings, and the occurrence of newton rings will cause the visibility of the fingers of the user when touching the screen to be reduced.

Disclosure of Invention

Some embodiments of the present invention disclose a polarizer structure, comprising a polarizer composite layer, a first adhesive layer and a first cover layer, wherein the polarizer composite layer comprises a polarizer and a first protective layer disposed on a first surface of the polarizer, and the first protective layer is disposed away from the polarizer and has a rough surface. In some embodiments, the roughness of the rough surface is measured by scanning in a direction perpendicular to the absorption axis direction of the polarizer, and the sum of the height of the top of a highest projection and the depth of the bottom of a deepest recess with respect to an average roughness center line of the roughness of the rough surface is defined as a maximum surface roughness (Sz) in the range of 0.45 μm to 5.1 μm. Furthermore, the first adhesive layer is positioned on the rough surface of the first protective layer, and the first covering layer is positioned on the first adhesive layer. According to an embodiment, the first cover layer may serve as a protective film for protecting the first protection layer, and the first adhesive layer may fill the gaps between the asperities of the rough surface of the first protection layer.

Some embodiments of the present invention disclose a display device, which includes the polarizer composite layer of the polarizer structure. The polarizing plate composite layer is positioned on the first side of the display component.

Some embodiments of the present invention disclose a method for manufacturing a polarizer structure, comprising providing a polarizer composite layer, wherein the polarizer composite layer comprises a polarizer and a first protective layer on a first surface of the polarizer, and the first protective layer is away from the polarizer and has a rough surface. In some embodiments, scanning in a direction perpendicular to the absorption axis direction of the polarizer is performed to determine the roughness of the rough surface, and the sum of the height of the top of a highest protruding portion and the depth of the bottom of a deepest recessed portion with respect to an average roughness center line of the roughness of the rough surface is defined as a maximum surface roughness (Sz), and the maximum surface roughness is in a range of 0.45 μm to 5.1 μm. In some embodiments, the method for manufacturing the polarizer structure further comprises providing a first cover layer and a first adhesive layer composition; coating the first adhesive layer composition on one surface of the first covering layer to form a first adhesive layer. In some embodiments, the method for manufacturing a polarizer structure further includes adhering the first cover layer to the rough surface of the first protective layer through the first adhesive layer.

Some embodiments of the present invention disclose a method for evaluating a polarizer structure, comprising providing a polarizer composite layer, wherein the polarizer composite layer comprises a polarizer and a first protective layer on a first surface of the polarizer, and the first protective layer is away from the polarizer and has a rough surface; measuring an initial haze value of the first protective layer; arranging a first adhesive layer on the rough surface of the first protective layer; arranging a first covering layer on the first adhesive layer, wherein the polarizing plate composite layer, the first adhesive layer and the first covering layer form a polarizing plate structure; and measuring a bonding haze value of the first protective layer provided with the first adhesive layer and the first covering layer, and obtaining a difference value between the bonding haze value and the initial haze value, wherein the percentage of the difference value relative to the initial haze value is a haze value change rate, and the bonding state of the rough surfaces of the first adhesive layer and the first protective layer is evaluated to be good if the haze value change rate is greater than or equal to 80%.

Drawings

FIG. 1 is a schematic cross-sectional view illustrating a polarizer structure according to some embodiments of the present disclosure;

FIG. 2A is a schematic view showing the center line average roughness of a surface profile curve obtained by scanning a concave-convex surface in a direction perpendicular to the absorption axis direction of a polarizer;

FIG. 2B is a schematic diagram showing the maximum roughness of the surface profile curve obtained by scanning a concave-convex surface in a direction perpendicular to the direction of the absorption axis of the polarizer;

FIG. 3 is a schematic cross-sectional view illustrating a polarizer structure according to other embodiments of the present disclosure;

FIG. 4 is a schematic cross-sectional view of a polarizer structure according to still other embodiments of the present disclosure;

FIG. 5 is a schematic cross-sectional view of a polarizer structure according to some other embodiments of the present disclosure;

FIG. 6 is a schematic cross-sectional view of a display device to which a polarizer structure according to some embodiments of the present disclosure is applied;

fig. 7 is a schematic diagram illustrating a method for manufacturing a polarizer structure according to an embodiment of the present disclosure.

[ notation ] to show

100-1, 100-2, 100-3, 100-4 polarizer structure

110 composite layer of polarizing plate

112 polarizer

112a first surface of the polarizer

112b second surface of the polarizer

114 first protective layer

114a rough surface of the first protective layer

114b bottom surface of the first protective layer

116a second protective layer

116a, 116b surface of the second protective layer

122 first adhesive layer

126 second adhesive layer

124 first cover layer

128 second cover layer

L is length

Maximum roughness (Ry) (Rmax)

Sz maximum surface roughness

Rp height of highest peak

Rv depth of lowest valley

600 display device

601 display assembly

601a, 601b surface of display element

603 lower polarizing plate

70A, 70B, 71, 72 coating apparatus

80A, 80B, 82A, 82B roller

Detailed Description

Embodiments of the present disclosure provide a polarizer structure, a method of manufacturing the same, and a display device including the polarizer structure. In some embodiments, the polarizer structure includes a protective layer (e.g., the first protective layer 114) on the polarizer, and the protective layer has a rough surface (e.g., the rough surface 114a) on a side away from the polarizer. In some embodiments, the maximum surface roughness (maximum surface roughness) of the rough surface is in the range of 0.45 μm to 5.1 μm. When the display device of the polarizing plate structure of the embodiment is applied, when ambient light is irradiated to the display device, the rough surface can improve the antiglare property of the display device and improve the visibility of the display device. Furthermore, the rough surface can also suppress the generation of Newton's rings. If the display device using the polarizer structure of the embodiment has a touch function, the visibility of the touch of the user's finger can be improved by suppressing the newton's rings. In addition, in some embodiments, it is further proposed to increase the thickness of an adhesive layer (e.g., the first adhesive layer 122) for attaching a cover layer (e.g., the first cover layer 124) to the protective layer so as to fully fill the gap between the rough surface and the concave-convex of the protective layer, thereby preventing air bubbles from remaining between the adhesive layer and the protective layer, and further reducing or even eliminating the generation of the color difference. And after pressure defoaming (autoclave), the polarizing plate structure of the embodiment has no phenomenon of unevenness or foaming.

While the present disclosure has been described in terms of various specific embodiments or examples, it is to be understood that these specific embodiments are merely exemplary and are not to be considered as limiting the scope of the disclosure. For example, when a first element is formed over a second element in the description, the description may include embodiments in which the first element is in direct contact with the second element, and may also include embodiments in which other elements are formed between the first element and the second element, wherein the first element and the second element are not in direct contact. The same or similar reference numbers are used in different embodiments and figures to denote the same or similar elements, but are used for simplicity and clarity in describing the disclosure and do not necessarily indicate a particular relationship between the various embodiments and/or structures being discussed. It should be noted that the embodiments are provided only for illustrating the technical features of the disclosure, and not for limiting the claims of the disclosure. Those skilled in the art will recognize that, based on the following description, equivalent modifications and variations can be made without departing from the spirit of the disclosure. Some elements are omitted from the drawings in some embodiments to clearly show the technical features of the disclosure.

Furthermore, spatially relative terms, such as "below …," "below," "…," "between …," and the like, may be used herein to facilitate describing the relationship of element(s) or feature(s) to other element(s) or feature(s) in the drawings and may encompass different orientations of the device in use or operation and the orientation depicted in the drawings. The device may be turned to a different orientation (rotated 90 degrees or otherwise), and the spatially relative adjectives used herein may be similarly interpreted. It should be understood that some process steps may include additional process steps before, during, or after the performance of the process steps, and some process steps described in some embodiments may be replaced or deleted by other process steps in methods of other embodiments.

Fig. 1 is a schematic cross-sectional view illustrating a polarizer structure 100-1 according to some embodiments of the present disclosure. As shown in fig. 1, the polarizer structure 100-1 includes a polarizer composite layer 110, a first adhesive layer 122 and a first cover layer 124, wherein the first cover layer 124 is attached to the polarizer composite layer 110 through the first adhesive layer 122.

In some embodiments, the polarizer composite layer 110 includes a polarizer 112 and a first protection layer 114, wherein the first protection layer 114 is disposed on the first surface 112a of the polarizer 112. According to an embodiment of the disclosure, the first protection layer 114 has a rough surface 114a on a side away from the polarizer 112, wherein the first adhesive layer 122 is disposed on the rough surface 114a of the first protection layer 114, and the first adhesive layer 122 fills up gaps between the protrusions and the recesses of the rough surface 114 a.

In some embodiments, the polarizer 112 is, for example, an iodine polarizer comprising a polyvinyl alcohol (PVA) resin film and iodine adsorbed and guided therein/thereon. A polyvinyl alcohol (PVA) resin film may be prepared by saponifying a polyvinyl acetate resin. Examples of the polyvinyl acetate resin include a homopolymer of vinyl acetate, i.e., polyvinyl acetate, and a copolymer of vinyl acetate and other monomers copolymerizable with vinyl acetate. Examples of other monomers copolymerizable with vinyl acetate include unsaturated carboxylic acids (e.g., acrylic acid, methacrylic acid, ethyl acrylate, n-propyl acrylate, methyl methacrylate), olefins (e.g., ethylene, propylene, 1-butene, 2-methylpropene), vinyl ethers (e.g., ethyl vinyl ether, methyl vinyl ether, n-propyl vinyl ether, isopropyl vinyl ether), unsaturated sulfonic acids (e.g., vinylsulfonic acid, sodium vinylsulfonate), and the like. In the embodiment of the present disclosure, the polarizer structure 100-1 is, for example, a continuous roll or a sheet material.

In some embodiments, the first protective layer 114 can be a single layer or a multi-layer structure. The material of the first protective layer 114 may be, for example, a thermoplastic resin excellent in transparency, mechanical strength, thermal stability, moisture barrier property, and the like. The thermoplastic resin may include a cellulose resin (e.g., TAC), TAC, dace, acrylic resin (e.g., polymethyl methacrylate (PMMA), polyester resin (e.g., polyethylene terephthalate (PET), polyethylene naphthalate), olefin resin, polycarbonate resin, cycloolefin resin, oriented-stretched polypropylene (OPP), Polyethylene (PE), polypropylene (PP), cycloolefin polymer (COP), cycloolefin copolymer (COC), polycarbonate (polycarbonate), Polycarbonate (PC), or any combination thereof, in some other embodiments, the material of the first protective layer 114 is, for example, (meth) acrylic, urethane, polyurethane, or any combination thereof, Thermosetting resins such as epoxy resins and silicone resins, and ultraviolet curing resins.

Furthermore, the first protection layer 114 can be attached to the first surface 112a of the polarizer 112 through a suitable adhesive layer (not shown). The adhesive layer preferably has adhesion such that peeling does not occur in an environment where the polarizing plate structure may be exposed. In some embodiments, the adhesive layer used to attach the first protective layer 114 and the polarizer 112 includes acrylic adhesives, silicone adhesives, and rubber adhesives. Among them, an acrylic adhesive may be used (but not limited thereto) in view of transparency, weather resistance, heat resistance and processability.

The adhesive layer for attaching the first protective layer 114 and the polarizer 112 may be appropriately prepared with one of various additives such as a tackifier, a plasticizer, glass fibers, glass beads, metal powder, other inorganic powder, a pigment, a colorant, a filler, an antioxidant, an ultraviolet absorber, an antistatic agent, and a silane coupling agent, or a combination of the above additives, as required.

According to some embodiments of the present disclosure, the colloidal material included in the first adhesive layer 122 may increase the amount of deformation with increasing pressure. For example, the first adhesive layer 122 is a Pressure Sensitive Adhesive (PSA) layer, or other suitable adhesive material.

In some embodiments, the composition for forming the first adhesive layer 122 includes a (meth) acrylic copolymer and a bridging agent.

In some embodiments, the weight average molecular weight of the (meth) acrylic copolymer is 300,000 to 3,000,000.

In some embodiments, the (meth) acrylic copolymer comprises, but is not limited to, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, or any combination of the foregoing. Further, the (meth) acrylic acid copolymer may be used singly or in combination of plural kinds.

Herein, the use of parentheses to describe compounds is meant to encompass the presence and absence of the parenthetical letters, such as the aforementioned case of methyl (meth) acrylate, including methyl acrylate, and methyl methacrylate.

In some embodiments, the bridging agent includes, but is not limited to, an isocyanate compound, an epoxy compound, an aziridine compound, or a metal chelate. Preferably, an isocyanate compound is used as the crosslinking agent. The bridging agent may be used singly or in combination.

In some embodiments, the composition forming the first adhesive layer 122 may further include an antistatic material. Specific examples of the antistatic material may include, but are not limited to, cationic antistatic agents having cationic groups such as quaternary ammonium salts, pyridinium salts, primary amino groups, secondary amino groups, or tertiary amino groups; an anionic antistatic agent having an anionic group such as a sulfonic acid base, a sulfate base, a phosphate base, or a phosphonic acid base; amphoteric antistatic agents such as amino acids and amino sulfates; nonionic antistatic agents such as aminoalcohols, glycerols, and polyethylene glycols; or a polymer type antistatic agent obtained by the polymerization reaction of the antistatic agent. The antistatic material may be used singly or in combination of plural kinds. In one example, the first adhesive layer 122 may include an ammonium salt, such as a quaternary ammonium salt, wherein the quaternary ammonium salt is added to improve antistatic effect.

In some embodiments, the composition forming the first adhesive layer 122 may further optionally include a silane coupling agent, an antistatic agent, an adhesion promoter, a crosslinking promoter, other suitable additives, or any mixture thereof.

In some embodiments, the material of the first cover layer 124 includes polyester resin, olefin resin, cellulose acetate resin, polycarbonate resin, acrylic resin, polybutylene terephthalate (PET), Polyethylene (PE) or Polypropylene (PP), cyclic olefin resin, other suitable cover materials, or a combination of the foregoing.

Furthermore, the first protection layer 114 of the above-mentioned embodiments of the present disclosure may be roughened by surface treatment to form a roughened surface 114 a. In addition, the first protective layer 114 may be further subjected to other surface treatment, such as antireflection treatment, hard coating treatment, electrification preventing treatment, anti-staining treatment, other suitable surface treatment, or a combination of the foregoing treatments. In some embodiments, the surface of the first protection layer 114 away from the polarizer 112 is at least roughened, so that the first protection layer 114 has a rough surface 114 a.

In addition, the first protection layer 114 has a bottom surface 114b on the first surface 112a of the polarizer 112, and the bottom surface 114b of the first protection layer is opposite to the rough surface 114a of the first protection layer. The surface roughness of the bottom surface 114b of the first protective layer and the rough surface 114a may be the same or different. In some embodiments, the surface roughness of the rough surface 114a is greater than the surface roughness of the bottom surface 114 b.

According to the embodiments of the present disclosure, the rough surface 114a of the first protection layer 114 can improve the anti-glare property of the display device. Especially, for a display device (for example, a public information display) used under a strong ambient light source, glare is more easily caused, and visibility is poor, and the polarizing plate structure applying some embodiments of the disclosure can obviously improve anti-glare property and visibility.

Furthermore, since the display device (e.g. public information display) usually has a touch function, after the display device is placed in an external housing with a glass cover plate, the surface of the polarizer of the display device will be attracted to the glass cover plate to generate newton rings, and the appearance of the newton rings will reduce the visibility of the user's finger when touching the screen. However, if the first protection layer 114 of the embodiment of the disclosure is applied to the polarizer structure, the generation of newton rings can be suppressed by using the rough surface 114a, so as to improve the visibility of the touch of the finger of the user.

According to some embodiments of the present disclosure, the rough surface 114a of the first protective layer 114 is measured by scanning in a vertical direction with respect to the absorption axis direction of the polarizer 112, and the sum of the height of the top of a highest convex portion and the depth of the bottom of a deepest concave portion (or "the sum of the vertical distances from a highest peak portion and a lowest valley portion, respectively, to the mean line") is defined as a maximum surface roughness (maximum surface roughness) with respect to a mean roughness center line of the roughness of the rough surface. In some embodiments, the rough surface 114a of the first passivation layer 114 has a maximum surface roughness (maximum surface roughness) in a range of 0.45 μm to 5.1 μm. The definition of the maximum surface roughness is explained below. Please refer to fig. 2A and 2B. Fig. 2A is a schematic diagram of the center line average roughness of the surface profile curve obtained by scanning a concave-convex surface in a direction perpendicular to the absorption axis direction of the polarizer. As shown in fig. 2A, assuming that the length L is extracted from the surface profile curve, the centerline in the length is taken as the X-axis, and the value obtained by dividing the sum of the areas of all the diagonal portions in the length L by the measured length L is taken as the centerline average roughness Ra. The formula can be expressed as Ra ═ f (x) dx/L. The arithmetic mean height Sa of the surface is a parameter obtained by enlarging the center line average roughness Ra (i.e., the arithmetic mean height of the line) in a planar manner. The absolute value of the difference in height at each point is shown averaged with respect to the average plane of the surface. The arithmetic mean height Sa of the surface is generally used to evaluate the surface roughness.

Fig. 2B is a schematic diagram showing the maximum roughness of the surface profile curve obtained by scanning a concave-convex surface in a direction perpendicular to the absorption axis direction of the polarizer. As shown in fig. 2B, assuming that the length L is extracted from the surface profile curve, the vertical distance from the highest peak to the lowest valley of the surface profile curve within the length L (i.e., the sum of the height Rp of the highest peak and the depth Rv of the lowest valley) is the maximum roughness ry (rmax), which can be expressed as ry (rmax) ═ Rp + Rv. The maximum surface roughness Sz is a parameter obtained by enlarging the maximum roughness ry (rmax) in a planar manner.

According to the above, although the anti-glare property of the display device to be applied can be improved by increasing the surface roughness of the first protective layer 114, the occurrence of newton's rings can be suppressed if the display device has a touch function. It should be noted that, when the roughness of the rough surface 114a of the first protection layer 114 is higher, the risk of air bubbles remaining between the first adhesive layer 122 and the rough surface 114a is increased during the production of the polarizer structure, which also causes the problems of generation of different colors and foaming of the first protection layer 124 during the post-processing, and causes the post-processing manufacturer to determine the polarizer composite layer 110 (at least including the polarizer 112 and the first protection layer 114) as a defective product. The problems of discoloration and foaming are explained below.

If the polarizing plate composite layer 110 and the first cover layer 124 coated with the first adhesive layer 122 are laminated by a nip roll (nip roll) composed of a plurality of rollers and a general laminating condition in the subsequent processing, the larger the surface roughness of the rough surface 114a of the first protective layer 114 is, the less easily the first adhesive layer 122 is able to fully fill the gaps between the protrusions and recesses of the rough surface 114a, and bubbles are generated. Therefore, even though the residual air bubbles between the first adhesive layer 122 and the rough surface 114a of the first protection layer 114 at the bonding position are eliminated, the air bubbles may remain between the first adhesive layer 122 and the rough surface 114a at the non-bonding position. When the polarizer structure is viewed, the difference in residual bubble density in different areas will create a color difference problem.

Furthermore, after the polarizer structure and the display module are bonded, the panel factory performs a pressure defoaming (auto-close) process. If bubbles originally remain between the first cover layer 124 and the rough surface 114a of the first protective layer 114 (the rough surface 114a has too large surface roughness to fill the concave-convex surface with the first adhesive layer 122), the bubbles remaining between the first protective layer 114 and the first cover layer 124 become larger during the pressure defoaming step, which may cause the first cover layer 124 to be uneven and even foamed.

The above-mentioned problems of color variation and foaming can cause the quality of the polarizer structure to be misjudged as abnormal, and the polarizer structure is discarded as a defective product. In view of the above, some embodiments of the present disclosure also provide a method for avoiding the above problem to remove/reduce the residual air bubbles between the first passivation layer 114 and the first passivation layer 124, thereby avoiding misjudging the quality of the polarizer structure. According to some embodiments, the thickness of the first adhesive layer 122 is increased to more effectively fill the uneven surface.

In some embodiments, the thickness of the first adhesive layer 122 coated on the first cover layer 124 is in the range of 16 μm to 26 μm. In some embodiments, a pressure sensitive adhesive layer may be coated on the first cover layer 124 by a pressure sensitive adhesive coating apparatus to form the first adhesive layer 122. The thickness of the first adhesive layer 122 is set forth herein before the first covering layer 124 is attached to the rough surface 114a of the first protection layer 114.

In some embodiments, the maximum surface roughness of the rough surface 114a of the first protective layer 114 is in the range of 2.9 μm to 5.1, and the thickness of the first adhesive layer 122 is in the range of 19.5 μm to 26 μm.

As described above, when the thickness is increased, the deformation amount of the first adhesive layer 122 is increased (for example, the deformation amount of the adhesive layer with the thickness of 25 μm is larger than that of the adhesive layer with the thickness of 15 μm), so that the uneven rough surface 114a can be filled more effectively, and the existence of air bubbles in the polarizer structure (for example, between the polarizer composite layer 110 and the first cover layer 124) can be reduced, even no air bubbles are generated. Therefore, when the polarizer structure is attached to the display module and is defoamed under pressure, the foaming of the first cover layer 124 can be reduced or even completely avoided.

FIG. 3 is a cross-sectional view of a polarizer structure 100-2 according to other embodiments of the present disclosure. In the following embodiments, the same or similar elements as those in the previous embodiments are denoted by the same or similar element numbers, and the description of the same or similar elements is referred to the foregoing description, and thus the description thereof is omitted.

The difference between the polarizer structure 100-2 of FIG. 3 and the polarizer structure 100-1 of FIG. 1 is that the polarizer structure 100-2 is further provided with another protection layer (i.e., a second protection layer 116) on the other side of the polarizer 112. The second protection layer 116 is disposed on the second surface 112b of the polarizer 112, and the second surface 112b of the polarizer 112 is opposite to the first surface 112a of the polarizer 112. The material and characteristics of the second passivation layer 116 are similar to those of the first passivation layer 114, and are not described herein again.

In this embodiment, the presence of the second protective layer 116 may further protect the second surface 112b of the polarizer 112. In some embodiments, the thickness of the second protective layer 116 is in the range of 20 μm to 80 μm. In some embodiments, the thickness of the second protective layer 116 is in the range of 25 μm to 60 μm.

Furthermore, the first protective layer 114 and the second protective layer 116 may be attached to the first surface 112a and the second surface 112b of the polarizer 112 through suitable adhesive layers (not shown), for example. Suitable materials for the adhesive layer are described above. The surface roughness of the two

opposite surfaces

116a and 116b of the second protective layer 116 is not particularly limited, and may be different from (e.g., smaller than) the surface roughness of the rough surface 114a of the first protective layer 114. In some embodiments, the maximum surface roughness of the rough surface 114a of the first protective layer 114 is greater than the maximum surface roughness of the

surfaces

116a and 116b of the second protective layer 116.

Fig. 4 is a schematic cross-sectional view illustrating a polarizer structure 100-3 according to still other embodiments of the present disclosure. The difference between the polarizer structure 100-3 of FIG. 4 and the polarizer structure 100-2 of FIG. 3 is that the polarizer structure 100-3 further has a second adhesive layer 126 and a second cover layer 128 disposed on the surface of the second passivation layer 116.

The material and characteristics of the second passivation layer 116 are similar to those of the first passivation layer 114, and are not described herein again. In some embodiments, the thickness of the second protective layer 116 is in the range of 20 μm to 80 μm. In some embodiments, the thickness of the second protective layer 116 is in the range of 25 μm to 60 μm.

Furthermore, in this embodiment, the first adhesive layer 122 and the second adhesive layer 126 are respectively attached to the first passivation layer 114 and the second passivation layer 116. As shown in FIG. 4, the first adhesive layer 122 is attached to the rough surface 114a of the first passivation layer 114, and the second adhesive layer 126 is attached to the surface 116b of the second passivation layer 116. The surface roughness of the rough surface 114a of the first protection layer 114 and the surface 116b of the second protection layer 116 is not particularly limited, and may be the same or different. In some embodiments, the maximum surface roughness of the rough surface 114a of the first protection layer 114 is greater than the maximum surface roughness of the surface 116b of the second protection layer 116 attached to the second adhesive layer 126. For example, the maximum surface roughness of the rough surface 114a of the first protective layer 114 may be in the range of 0.45 μm to 5.1 μm, and the maximum surface roughness of the surface 116b of the second protective layer 116 may be below 0.45 μm. The disclosure does not particularly limit the surface roughness of the surface 116b of the second passivation layer 116, as long as the second adhesive layer 126 can be smoothly adhered to the surface 116b of the second passivation layer 116.

In this embodiment, the first cover layer 124 is attached to the polarizer composite layer 110 through the first adhesive layer 122, and the second cover layer 128 is attached to the polarizer composite layer 110 through the second adhesive layer 126. The second cover layer 128 may protect the surface 11b of the second protective layer 116. According to some embodiments, the second cover layer 128 is a release film, and when the polarizer structure is to be attached to a display device, the second cover layer 128 is removed, leaving the second adhesive layer 126 attached to the display device.

In some embodiments, the composition and characteristics of the second adhesive layer 126 are different from those of the first adhesive layer 122, so that the first adhesive layer 122 can be removed along with the first cover layer 124, and the second adhesive layer 126 remains in the structure of the polarizer after the second cover layer 128 is removed. In some embodiments of the present invention, the,

the second adhesive layer 126 is formed of an adhesive, such as a Pressure Sensitive Adhesive (PSA). The composition of the adhesive mainly includes but is not limited to: (A) a main agent, (B) a crosslinking agent, and (C) a silane coupling agent. In some embodiments, the base agent comprises at least one (meth) acrylate, meaning any of acrylate or methacrylate, which may be selected, for example, from: linear alkyl (meth) acrylates such as methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, n-octyl (meth) acrylate, and undecyl (meth) acrylate; or may be selected, for example, from: branched alkyl (meth) acrylates such as isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and isooctyl (meth) acrylate; or may be selected, for example, from: alkyl (meth) acrylates substituted with an alkoxy group such as 2-methoxyethyl (meth) acrylate and ethoxymethyl (meth) acrylate. In addition, the (meth) acrylate may contain an aryl group such as benzyl (meth) acrylate and the like; alternatively, the (meth) acrylate may contain aryloxy groups such as 2-phenoxyethyl (meth) acrylate, 2- (2-phenoxyethoxy) ethyl (meth) acrylate, ethylene oxide-modified (meth) acrylate of nonylphenol, 2- (o-phenylphenoxy) ethyl (meth) acrylate, and the like. The cross-linked (methyl) acrylate after the solidification and drying is used as the main component and the framework of the adhesive layer. The bridging agent can help the (methyl) acrylate monomer in the main agent to generate crosslinking to form a network structure and improve the strength of the adhesive layer, the molecule of the bridging agent has at least two functional groups which can react with the polar functional group of the (methyl) acrylate monomer in the main agent, and the bridging agent is an epoxy bridging agent, an isocyanate bridging agent, an imine bridging agent, a metal chelate bridging agent and an aziridine bridging agent, and can be selected from one or a mixture of a plurality of bridging agents. The adhesion between the adhesive layer and the substrate (especially, the glass substrate) can be improved by adding a silane coupling agent, which can be selected from, for example: silane compounds containing polymerizable unsaturated groups (e.g., ethylenic bonds) such as vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (2-methoxyethoxy) silane, and 3-methacryloxypropyltrimethoxysilane; or may be selected, for example, from: silane compounds having an epoxy structure such as 3-glycidoxypropyltrimethoxysilane, 2- (3, 4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltriethoxysilane, and 3-glycidoxypropylethoxydimethylsilane; or may be selected, for example, from: amino group-containing silane compounds such as 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane and N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane; or may be selected, for example, from: silane compounds containing a halogen substituent such as 3-chloropropylmethyldimethoxysilane and 3-chloropropyltrimethoxysilane; others are, for example: 3-methacryloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, and the like. Furthermore, the thickness of the second adhesive layer 126 and the thickness of the first adhesive layer 122 may be the same or different. In some embodiments, the thickness of the second adhesive layer 126 is in the range of 10 μm 50 μm. In some other embodiments, the thickness of the second adhesive layer 126 is in the range of 15 μm to 30 μm.

Further, the material of the second cover layer 128 may be different from or the same as the material of the first cover layer 124. The second cover layer 128 includes a material such as a conventional release film. Furthermore, the thickness of the second cover layer 128 may be the same as or different from the thickness of the first cover layer 124. In some embodiments, the thickness of the second cover layer 128 is in the range of 15 μm to 100 μm. In some other embodiments, the thickness of the second cladding layer 128 is in the range of 38 μm to 50 μm. The material of the second cover layer 128 is not particularly limited, and all base material sheets that are general adhesive sheets can be used. Examples of the optical member (optical film) include, in addition to a desired optical member: woven or nonwoven fabrics using fibers such as rayon, acrylic, and polyester; synthetic paper; high-quality paper, cellophane, impregnated paper, coated paper and the like; metal foils such as aluminum and copper; foams such as urethane foams and polyethylene foams; plastic films such as polyester films including polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, polyurethane films, polyethylene films, polypropylene films, cellulose films including triacetyl cellulose, polyvinyl chloride films, polyvinylidene chloride films, polyvinyl alcohol films, ethylene-vinyl acetate copolymer films, polystyrene films, polycarbonate films, acrylic resin films, norbornene resin films, and cycloolefin resin films; and a laminate of two or more of these. The plastic film may be uniaxially or biaxially oriented.

Fig. 5 is a schematic cross-sectional view illustrating a polarizer structure 100-4 according to some other embodiments of the present disclosure. The difference between the polarizer structure 100-4 of FIG. 5 and the polarizer structure 100-3 of FIG. 4 is that the polarizer structure 100-4 does not include the second passivation layer 116 opposite to the polarizer structure 100-3.

As shown in fig. 5, the polarizer structure 100-4 of the embodiment includes a polarizer composite layer 110, a first adhesive layer 122, a first cover layer 124, a second adhesive layer 126, and a second cover layer 128.

< display device >

FIG. 6 is a schematic cross-sectional view of a display device to which a polarizer structure according to some embodiments of the present disclosure is applied. The display device 600 can be obtained by disposing the polarizer structure of the embodiment on one side of another optical member (e.g., the display module 601).

The display device of fig. 6 includes the polarizing plate composite layer 110 shown in fig. 3,4 and 5, for illustration. More specifically, in the case where the peelable second cover layer 128 is present in the polarizing plate structure, after the peeling of the second cover layer 128, the other part of the polarizing plate structure is adhesively bonded to another optical member via the second adhesive layer 126.

Please refer to fig. 3,4, and 6. According to some embodiments, the second cover layer 128 is removed before the lamination process, and then the remaining material layer of the polarizer structure 100-2, 100-3 or 100-4 is laminated to the display module 601 through the adhesion of the second adhesive layer 126. After the attaching, the first cover layer 124 is removed, and the first adhesive layer 122 is removed together with the first cover layer 124. The display module 601 includes a liquid crystal cell (liquid crystal cell) or an organic electroluminescent device. The liquid crystal display device can be obtained by disposing the polarizing plate composite layer on one side of the liquid crystal cell, and the organic electroluminescent display device can be obtained by disposing the polarizing plate composite layer on the organic electroluminescent element. Furthermore, in some embodiments, the display device 600 as shown in FIG. 6 further comprises a lower polarizer 603 on a second side of the display element 601, wherein the second side of the display element 601 is opposite to the first side of the display element 601. In fig. 6, the first side of display assembly 601 is referred to as being above surface 601a of display assembly 601 and the second side is referred to as being below surface 601b of display assembly 601. In one embodiment, the Display component 601 may be a Public Information Display (PID).

< method for manufacturing polarizing plate Structure >

According to some embodiments of the present disclosure, a method for manufacturing a polarizer structure is provided. Referring to fig. 1, a method for manufacturing the polarizer structure shown in fig. 1 is illustrated.

First, a polarizer composite layer 110 is provided, wherein the polarizer composite layer 110 includes a polarizer 112 and a first protection layer 114 disposed on a first surface 112a of the polarizer 112, and the first protection layer 114 is disposed away from the polarizer 112 and has a rough surface 114 a.

In some embodiments, scanning in a direction perpendicular to the absorption axis direction of the polarizer 112 is performed to row-measure the roughness of the rough surface 114a, and the sum of the height of the top of an uppermost protrusion and the depth of the bottom of a deepest recess with respect to an average roughness center line of the roughness of the rough surface 114a is defined as a maximum surface roughness (Sz). In some embodiments, the maximum surface roughness is in the range of 0.45 μm to 5.1 μm.

Next, in some embodiments, a first cover layer 124 and a first adhesive layer composition are provided. And coating the first adhesive layer composition on a surface of the first cover layer 124 to form the first adhesive layer 122.

Then, the first cover layer 124 is attached to the rough surface 114a of the first protection layer 114 through the first adhesive layer 122.

In actual manufacturing, the polarizer and other material films required in the polarizer structure may be sequentially bonded by continuous transmission to obtain various polarizer structures as proposed in the above embodiments.

More specifically, for example, a long roll of a polarizing plate structure (wound product) can be continuously manufactured by using a long unstretched polyvinyl alcohol resin film (raw material film of the polarizer 112) as a starting material, continuously conveying the film along a film conveying path of a manufacturing apparatus of the polarizing plate structure, sequentially laminating the film with other material film layers in the polarizing plate structure except for performing a predetermined treatment step. The manufactured polarizer structure may be square or long, wherein the square polarizer structure may be obtained by cutting the long polarizer structure.

Hereinafter, a polarizer structure including the polarizer 112, two protective layers and two cover layers is taken as an example for illustrating the manufacturing method. However, the present disclosure is not limited to the following methods for manufacturing the polarizer structure.

Please refer to fig. 4 and fig. 7 simultaneously. Fig. 7 is a schematic diagram illustrating a method for manufacturing a polarizer structure according to an embodiment of the present disclosure.

In this example, the raw material film of the polarizer 112 is used as a starting material, and is continuously transported along the film transport path of the manufacturing apparatus of the polarizer structure, and is sequentially bonded to the first protective layer 114, the second protective layer 116, the first adhesive layer 122, the first cover layer 124, the second adhesive layer 126, and the second cover layer 128, so as to continuously manufacture the polarizer structure roll.

As shown in FIG. 7, in some embodiments, a polarizer 112 is provided, and the polarizer 112 has a first surface 112a and a second surface 112b opposite to each other.

In some embodiments, the polarizer 112, as shown in FIG. 7, is formed after performing a plurality of suitable predetermined processing steps. The predetermined processing steps for fabricating the polarizer 112 may include, for example: the method includes a swelling treatment step of immersing the raw material film in a swelling bath, a dyeing treatment step of immersing the film after the swelling treatment step in a dyeing bath, and a crosslinking treatment step of immersing the film after the dyeing treatment step in a crosslinking bath. Then, the uniaxial extension process is performed in a wet or dry manner between the series of processing steps (i.e., before or after any one or more processing steps and/or in any one or more processing steps). Then, the resulting film is subjected to a drying treatment. Other processing steps may be added as appropriate.

In some embodiments, as shown in fig. 7, after the polarizer 112 formed by the above-mentioned multiple processing steps is transferred to a polarizer structure manufacturing apparatus, a suitable adhesive layer may be directly coated on the surface of the polarizer 112 for subsequent attachment with a protective layer (e.g., TAC) to form the polarizer composite layer 110 shown in fig. 4.

In some embodiments, as shown in FIG. 7, a suitable adhesive layer composition may be applied directly to the first surface 112a of the polarizer 112 by the application device 70A. A suitable adhesive layer composition may be applied to the second surface 112B of the polarizer 112 by the application device 70B. For simplicity and clarity, the adhesive layer composition layer coated on the first surface 112a and the second surface 112b of the polarizer 112 is omitted in FIG. 7.

Next, in some embodiments, as shown in FIG. 7, a first protective layer 114 may be attached to the first surface 112a of the polarizer 112, and a second protective layer 116 may be attached to the second surface 112b of the polarizer 112. For example, in some embodiments, as shown in fig. 7, the first protective layer 114 and the second protective layer 116 can be attached to the polarizer 112 by a roller

set including rollers

80A and 80B, for example, to form a polarizing plate composite layer 110.

Next, in some embodiments, as shown in fig. 7, a second adhesive layer 126 may be coated on the second protective layer 116 by the coating device 71.

In some embodiments, as shown in fig. 7, the first adhesive layer 122 may be first coated on the first cover layer 124 by the coating device 72. The coating device 72 is, for example, a pressure sensitive adhesive coating device.

Next, in some embodiments, as shown in fig. 7, the first cover layer 124 can be attached to the first protective layer 114 and the second cover layer 128 can be attached to the second protective layer 126 by a roller

set including rollers

82A and 82B. Thus, the polarizer structure 100-3 shown in FIG. 4 is formed.

< related experiments >

In order to make the above and other objects, features, and advantages of the present disclosure more comprehensible, several examples of polarizer structures are prepared, wherein the examples include a first adhesive layer 122 (used to attach the first cover layer 124 to the polarizer composite layer 110) with different thicknesses and a rough surface 114a of the first protective layer 114 with different roughness, and the samples are evaluated for color difference and pressure deaeration to determine the state of the samples. However, the contents of the following experimental examples are only for illustrative purposes and should not be construed as limitations of the practice of the present disclosure.

The structure of the sample of the experimental example is further described below. The following experimental examples are all exemplified by the polarizer structure 100-2 (including the first cover layer 124/the first adhesive layer 122/the first protective layer 114/the polarizer 112/the second protective layer 116) shown in fig. 3, wherein the polarizer is a polyvinyl alcohol (PVA) resin film, and the first protective layer 114 and the second protective layer 116 are both made of Triacetylcellulose (TAC). The following examples are, however, illustrative only and should not be construed as limiting the practice of the disclosure. The sample pretreatment and the characteristic evaluation method of the polarizer structure of the sample of the polarizer structure proposed in the experimental example are briefly described below. The detection and evaluation modes are not repeated when the detection results of all experimental examples are analyzed subsequently.

[ sample preparation and pretreatment of polarizing plate Structure ]

(a) First, a first adhesive layer composition and a first protective layer having rough surfaces with different roughness are prepared.

(b) The first adhesive layer composition with different thicknesses is coated on the surface of the first cover layer 124 to form the first adhesive layer 122.

(c) Then, the first adhesive layer 122 (used to attach the first cover layer 124 to the polarizing plate composite layer 110) with different thicknesses is attached to the rough surface 114a of the first protective layer 114 with different roughness, so as to prepare a plurality of sets of samples. Wherein the thickness of the first adhesive layer 122 of each sample of the experimental examples is shown in table 1.

Please refer to fig. 3 again. During the above bonding, the polarizer composite layer 110 and the first cover layer 124 with the first adhesive layer 122 of each sample enter the bonding machine respectively, and stop transmitting when contacting the Nip-Roll of the bonding machine, and continuously apply the bonding pressure (down pressure) of 0.3Mpa or other pressure values, and continue transmitting after 10 seconds. During the period of stopping transmission, the first adhesive layer 122 is deformed by the continuously applied bonding pressure (down force) to fill the gaps between the concave and convex parts on the rough surface 114a of the first protective layer 114, thereby eliminating bubbles.

(d) The prepared sample was placed in an environment of 23 ℃ and a relative humidity of 60%, and evaluated after 24 hours.

[ measurement of samples of polarizing plate Structure ]

(a) Thickness of the adhesive layer

In the present disclosure, for each sample of the polarizer structure of the experimental examples, after the first adhesive layer composition having different thicknesses was applied on the surface of the first cover layer 124, the thickness of the first adhesive layer 122 was measured using a digital gauge minor index (model ID-C112, sanfeng, japan).

(b) Surface roughness

The present disclosure is to measure the surface roughness of the rough surface 114a of the first protection layer 114 by using a 3D Laser confocal Microscope model OLS5000(OLYMPUS LEXT OLS 50003D Measuring Laser Microscope) for the samples of the polarizer structure of each experimental example. The average surface roughness Sa (i.e., the arithmetic mean height of the surface) and the maximum surface roughness Sz (i.e., the sum of the heights of the highest peaks and the depths of the lowest valleys) of the samples of the respective experimental examples are shown in table 1, wherein the average surface roughness Sa is defined with reference to fig. 2A and the related description, and the maximum surface roughness Sz is defined with reference to fig. 2B and the related description.

[ evaluation method of polarizing plate Structure ]

(A) Evaluation of color difference

The evaluation of the color difference is carried out by two methods, such as visual observation and measurement of the change in the haze value.

(A-1) visual observation

Subjecting the obtained polarized light toThe samples of the plate structure were placed in a general environment with an illuminance of 6000Lux (illuminance is the light intensity in a specific area, lumen/m)²) And performing reflection observation to determine whether a heterochromatic problem occurs. If the heterochrosis condition appears, the heterochrosis degree is further judged.

The degree of discoloration was determined by visual observation as follows:

observing the sample of the polarizer structure, and if the area ratio of the different color region exceeds 10% of the total area observed, it is evaluated as X (serious), which indicates that the adhesion condition of the first adhesive layer 122 and the rough surface 114a of the first protective layer 114 in the sample of the polarizer structure is not good;

observing the sample of the polarizer structure, and if the area of the different color region accounts for 5% to 10% of the total area observed, it is evaluated as Δ (medium), indicating that the adhesion condition of the first adhesive layer 122 and the rough surface 114a of the first protective layer 114 is general in the sample of the polarizer structure;

observing the sample of the polarizer structure, and if the area of the different color region accounts for 1% to 5% of the total area observed, it is evaluated as Δ to O (slight), indicating that the adhesion condition of the first adhesive layer 122 and the rough surface 114a of the first protective layer 114 is still acceptable in the sample of the polarizer structure;

when the sample of the polarizer structure was observed and the area of the different color region was 1% or less of the total area observed, even if there was no different color, the evaluation was O (no abnormality), indicating that the adhesion between the first adhesive layer 122 and the rough surface 114a of the first protective layer 114 was good in this sample of the polarizer structure. The results of determining the degree of discoloration by visually observing the structure of the polarizing plate are shown in Table 1.

(A-2) evaluation of color difference based on the change ratio of haze value

The method comprises the steps of manufacturing a sample of a multi-group polarizer structure, measuring an initial haze value before the first protective layer 114 is attached to the first adhesive layer 122 and the first cover layer 124, and measuring a haze value of the polarizer structure after the first protective layer 114 is attached to the first adhesive layer 122 and the first cover layer 124, wherein the percentage of the difference between the two haze values relative to the initial haze value is the haze value change rate. The HAZE value was measured using HAZE METER NDH 5000 manufactured by Nippon Denshoku industries.

If the bubbles are generated after the first protective layer 114 is bonded to the first adhesive layer 122 and the first cover layer 124 and is rolled, the light is scattered by the bubbles, and the haze value is not greatly changed. On the other hand, if the adhesion condition between the first adhesive layer 122 and the first protective layer 114 is good and there are few bubbles or no bubbles, the decrease range of the haze value is large, and the change rate of the haze value is high.

The initial haze values before and after the above-mentioned lamination, the haze value of the polarizing plate structure, the haze value change rate, and the results of judging the degree of discoloration from the haze value change rate are shown in table 2. Taking experimental example 1 as an example, when the initial haze value before lamination (i.e., the haze values of the three sets of the first protective layers 114 were measured and averaged) was 28.6 and the average haze value after lamination (i.e., the haze values of the three sets of the polarizer structure samples were measured and averaged) was 4.0, the haze value change rate was 100 × [ (28.6-4.0)/28.6] (86.1%).

The degree of discoloration was evaluated based on the obtained change rate of the haze value. The evaluation method is as follows:

if the haze value variation rate is less than 70%, it is evaluated as X (serious), which indicates that the adhesion condition between the first adhesive layer 122 and the rough surface 114a of the first protective layer 114 is not good (i.e., bubbles are still generated to scatter light) in the sample of the polarizer structure;

if the haze value change rate is 70% or more but less than 75%, it is evaluated as Δ (moderate), indicating that the bonding condition of the first adhesive layer 122 and the rough surface 114a of the first protective layer 114 in the sample of the polarizer structure is generally the same

If the haze value change rate is 75% or more but less than 80%, it is evaluated as Δ to O (slight), indicating that the adhesion condition of the first adhesive layer 122 and the rough surface 114a of the first protective layer 114 is satisfactory in the sample of the polarizer structure;

when the haze value change rate is 80% or more, O (no abnormality) is evaluated, indicating that the bonding condition of the first adhesive layer 122 and the rough surface 114a of the first protective layer 114 is good (that is, almost no bubbles are generated, and thus the haze value measured after bonding is low) in the sample of the polarizer structure.

Taking experimental example 1 in table 2 as an example, when the initial haze value before lamination (i.e., the haze values of the three sets of the first protective layers 114 were measured and averaged) was 28.6 and the average haze value after lamination (i.e., the haze values of the three sets of the polarizer structure samples were measured and averaged) was 4.0, the haze value change rate was 100 × [ (28.6-4.0)/28.6] ═ 86.1%. The haze value change rates for the remaining experimental examples in table 2 and so on. The results of the evaluation of the test examples for the measured haze value change in table 2 were the same as the results of the evaluation of the test examples for the visual observation in table 1.

(B) Evaluation after pressure defoaming

The sample was put into a pressure defoaming apparatus under pressure defoaming conditions of 60 ℃ and 0.5MPa for 1 hour. After the test, the sample was observed in reflection under a general environment (illuminance 6000Lux) to confirm whether the first cover layer 124 had a foaming problem.

The degree of heterochromia and foaming of the samples of each polarizer structure are shown in Table 1.

TABLE 1

(continuation table 1)

TABLE 2

(continuation table 2)

In the case where the thickness of the first adhesive layer 122 is not changed, the higher the roughness of the rough surface 114a of the first protective layer 114, the less likely the first adhesive layer 122 is to adhere to the rough surface, and air bubbles remain. According to the test results of the experimental examples in tables 1 and 2, it can be seen that: when the product of the ratio of the thickness of the first adhesive layer to the maximum surface roughness Sz and the bonding pressure is less than 0.2, the polarizing plate structure is prone to generate discoloration and foaming after pressure deaeration, please refer to experimental examples 3-6, 9, 11 and 12.

Therefore, according to some embodiments of the present disclosure, the thickness of the first adhesive layer 122, the maximum surface roughness Sz of the rough surface 114a of the first protective layer 114, and the bonding pressure are required to satisfy the following formula:

(thickness of the first adhesive layer/maximum surface roughness Sz of the roughened surface of the first protective layer) x bonding pressure >2.0,

wherein the thickness is in units of micrometers (μm), the maximum surface roughness is in units of micrometers (μm), and the bonding pressure is in units of mega pascal (MPa).

In some embodiments, the conforming pressure is in the range of 0.3MPa to 0.6 MPa. The application pressure of the present disclosure is not limited to the above-mentioned range. Please refer to tables 1 and 2 again. When the same bonding pressure is applied and the rough surface 114a of the first passivation layer 114 has a similar maximum surface roughness Sz, increasing the thickness of the first adhesive layer 122 will help fill the gaps between the asperities of the rough surface 114 a. For example, in each of the experimental examples 10 and 12, when the bonding pressure of the sample was 0.3MPa, the maximum surface roughness Sz of the rough surface 114a of the first protective layer 114 was 2.9 μm and 2.7 μm, respectively, and the thickness of the first adhesive layer 122 was 16.0 μm (experimental example 12) and 25.0 μm (experimental example 10), respectively, the sample of the polarizing plate structure of the experimental example 12 exhibited a moderate discoloration phenomenon, and also had a problem of foaming after the pressure defoaming.

According to the embodiment of the disclosure, under the same bonding pressure, when the maximum surface roughness Sz of the rough surface 114a of the first protection layer 114 is larger, the thickness of the first adhesive layer 122 is also larger, so as to increase the deformation amount of the first adhesive layer 122 and fill the gaps between the protrusions and the recesses of the rough surface 114 a. For example, in examples 1, 2, 7 to 8, and 10, the polarizing plate structure had no discoloration and no problem of foaming after pressure defoaming. According to some embodiments, the maximum surface roughness is in a range of 2.9 μm to 5.1 μm, and the thickness of the first adhesive layer is in a range of 19.5 μm to 26 μm. Applying the same bonding pressure and the rough surface 114a of the first passivation layer 114 has a similar maximum surface roughness Sz, increasing the thickness of the first adhesive layer 122 will help fill the gaps between the asperities of the rough surface 114 a. For example, in each of the experimental examples 10 and 12, when the bonding pressure of the sample was 0.3MPa, the maximum surface roughness Sz of the rough surface 114a of the first protective layer 114 was 2.9 μm and 2.7 μm, respectively, and the thickness of the first adhesive layer 122 was 16.0 μm (experimental example 12) and 25.0 μm (experimental example 10), respectively, the sample of the polarizing plate structure of the experimental example 12 exhibited a moderate discoloration phenomenon, and also had a problem of foaming after the pressure defoaming.

Please refer to tables 1 and 2. For example, in the samples of the polarizer structures of experimental examples 8 and 11, the maximum surface roughness Sz of the rough surface 114a of the first protective layer 114 was 3.1 μm and 3.3 μm, respectively, and the thickness of the first adhesive layer 122 was 19.5 μm (experimental example 8) and 21 μm (experimental example 11), respectively, whereas the sample of the polarizer structure of experimental example 11 was bonded by applying a bonding pressure of 0.3Pa, but a middle degree of discoloration occurred during the test, and there was a problem of foaming after the pressure defoaming. In contrast, in the polarizing plate of experimental example 8, the adhesion pressure was increased to apply the adhesion pressure of 0.6Pa, so that the degree of discoloration was improved and the problem of foaming was not caused even after pressure defoaming. However, it is noted that the polarizer structure proposed in experimental example 11, for example, in which the maximum surface roughness Sz of the rough surface 114a of the first protective layer 114 is 3.3 μm, can indeed improve the anti-glare property of the applied display device, except that the color difference and foaming problems may cause the polarizer structure to be misjudged as a quality abnormality during the post-processing manufacturing process and discarded as a defective product.

Although table 1 shows only examples of the lamination with lamination pressures of 0.3MPa and 0.6MPa, the present disclosure is not limited to these two lamination pressures, and other lamination pressures in the range of 0.3MPa to 0.6MPa, lower than 0.3MPa or higher than 0.6MPa, such as commonly used lamination pressures, may be applied as long as the lamination pressure does not exceed the pressure that can be borne by the mechanical strength of each film layer in the polarizer structure.

Further, although the polarizer composite layer 110 and the first cover layer 124 with the first adhesive layer 122 are bonded in the experimental example only by stopping the transmission when they contact the bonding machine, the present disclosure is not limited thereto, and the transmission may be stopped for a period of time (e.g., 10 seconds or more) after the lamination transmission of one or more press roller sets after entering the bonding machine, and the bonding pressure (down pressure) is continuously applied, and then the transmission is continued. The number of times and the time for stopping the transmission are not particularly limited in the present disclosure, and may be determined according to practical application conditions (for example, the thickness of the first adhesive layer 122, the surface roughness of the rough surface 114a of the first protective layer 114, the length of the material layer to be laminated, and the like), as long as the transmission is stopped, the first adhesive layer 122 can be deformed to fill the gaps between the concave and convex portions on the rough surface 114a of the first protective layer 114 by the continuously applied bonding pressure (down pressure), so as to eliminate the bubbles, which is the bonding method included in the present disclosure.

In summary, embodiments of the present disclosure provide a polarizer structure, a method of manufacturing the polarizer structure, and a display device including the polarizer structure. According to the embodiments of the present disclosure, the rough surface 114a of the first protection layer 114 can improve the anti-glare property of the display device. Especially, for a display device (for example, a public information display) used under a strong ambient light source, glare is more easily caused, and visibility is poor, and the polarizing plate structure applying some embodiments of the disclosure can obviously improve anti-glare property and visibility. The rough surface can also suppress the generation of Newton's rings. If the display device using the polarizer structure of the embodiment has a touch function, the visibility of the touch of the user's finger can be improved by suppressing the newton's rings. In addition, in some embodiments, it is further proposed to increase the thickness of the first adhesive layer 122 for attaching the first cover layer 124 on the first protective layer 114, so as to fully fill the gaps between the protrusions and recesses of the rough surface 114a of the first protective layer 114, so as to avoid the bubble residue between the first adhesive layer 122 and the first protective layer 114, thereby reducing or even eliminating the occurrence of the color difference. And the structure of the polarizer of the embodiment can not generate the phenomena of unevenness or foaming after being subjected to pressure defoaming (autoclave).

Although the present invention has been described with reference to the preferred embodiments, it should be understood that various changes and modifications can be made therein by those skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A polarizing plate structure, comprising:

a polarizing plate composite layer comprising:

a polarizer; and

a first protective layer on a first surface of the polarizer, the first protective layer being away from the polarizer and having a rough surface, wherein scanning is performed in a direction perpendicular to an absorption axis direction of the polarizer to measure roughness of the rough surface, and a sum of a height of a top of a highest convex portion and a depth of a bottom of a deepest concave portion with respect to an average roughness center line of the roughness of the rough surface is defined as a maximum surface roughness, the maximum surface roughness being in a range of 0.45 μm to 5.1 μm;

a first adhesive layer on the rough surface of the first protective layer; and

a first cover layer on the first adhesive layer.

2. The polarizing plate structure of claim 1, wherein the first adhesive layer has a thickness in a range of 16 μm to 26 μm.

3. The polarizing plate structure of claim 1, wherein the first protective layer has a bottom surface on the first surface of the polarizer, and the maximum surface roughness of the rough surface is greater than the maximum surface roughness of the bottom surface.

4. The polarizing plate structure of claim 1, wherein the polarizing plate composite layer further comprises:

the second protective layer is positioned on a second surface of the polaroid, and the second surface of the polaroid is opposite to the first surface of the polaroid.

5. The polarizing plate structure of claim 4, further comprising:

the second adhesive layer is positioned on a second surface of the polaroid, and the second surface of the polaroid is opposite to the first surface of the polaroid; and

and the second covering layer is attached to the polarizing plate composite layer through the second adhesive layer.

6. The polarizer structure of claim 5, wherein the maximum surface roughness of the rough surface of the first passivation layer is greater than the maximum surface roughness of the surface of the second passivation layer attached to the second adhesive layer.

7. The polarizing plate structure of claim 1, wherein the first adhesive layer is a pressure sensitive adhesive layer; and/or wherein the material of the first protective layer comprises Triacetylcellulose (TAC), Diacetylcellulose (DAC), Polymethylmethacrylate (PMMA), Polyethyleneterephthalate (PET), olefin resin, polycarbonate resin, cyclic olefin resin, oriented-stretched polypropylene (OPP), Polyethylene (PE), polypropylene (PP), Cyclic Olefin Polymer (COP), Cyclic Olefin Copolymer (COC), Polycarbonate (PC), or a combination thereof; and/or wherein the material of the polarizer comprises a polyvinyl alcohol (PVA) resin film and iodine adsorbed and guided therein/thereon; and/or wherein the material of the first cover layer comprises polyester resin, olefin resin, cellulose acetate resin, polycarbonate resin, acrylic resin, polybutylene terephthalate (PET), Polyethylene (PE) or Polypropylene (PP), cyclic olefin resin, or a combination of the foregoing materials.

8. A display device, comprising:

a display assembly; and

the polarizing plate composite layer of the polarizing plate structure of any one of claims 1 to 7, wherein the polarizing plate composite layer is disposed on the first side of the display device.

9. The display apparatus of claim 8, wherein the display element comprises a liquid crystal cell or an organic electroluminescent device.

10. A method of manufacturing a polarizer structure, comprising:

providing a polarizing plate composite layer, which comprises:

a polarizer; and

a first protective layer on a first surface of the polarizer, the first protective layer being away from the polarizer and having a rough surface, wherein scanning is performed in a direction perpendicular to an absorption axis direction of the polarizer to perform line measurement on irregularities of the rough surface, and a sum of a height of a top of a highest convex portion and a depth of a bottom of a deepest concave portion with respect to an average roughness center line of the irregularities of the rough surface is defined as a maximum surface roughness, the maximum surface roughness being in a range of 0.45 μm to 5.1 μm;

providing a first covering layer and a first adhesive layer composition;

coating the first adhesive layer composition on one surface of the first covering layer to form a first adhesive layer; and

the first covering layer is adhered to the rough surface of the first protection layer through the first adhesive layer.

11. The method of claim 10, wherein the thickness of the first adhesive layer is in a range of 16 μm to 26 μm after the first adhesive layer composition is coated on the first cover layer.

12. The method of claim 10, wherein a bonding tool is used to apply a bonding pressure to bond the first cover layer to the rough surface of the first protection layer through the first adhesive layer, and the thickness of the first adhesive layer, the maximum surface roughness of the rough surface of the first protection layer, and the bonding pressure satisfy the following formula:

(the thickness of the first adhesive layer/the maximum surface roughness of the rough surface of the first protective layer) × the bonding pressure >2.0,

wherein the thickness is in units of micrometers (μm), the maximum surface roughness is in units of micrometers (μm), and the bonding pressure is in units of megapascals (MPa).

13. The method for manufacturing a polarizing plate structure according to claim 12, wherein the bonding pressure applied is in a range of 0.3MPa to 0.6 MPa.

14. The method for manufacturing a polarizer plate structure according to claim 12, wherein the bonding machine comprises a roller set comprising a plurality of rollers, the polarizer plate composite layer and the first cover layer with the first adhesive layer are respectively conveyed into the bonding machine during the bonding, the conveyance is stopped for 10 seconds after contacting at least one of the roller sets of the bonding machine, and then the conveyance is continued,

during the period of stopping transmission, the laminating machine continuously applies the laminating pressure to enable the first adhesive layer to generate deformation so as to fill at least one part of the rough surface of the first protective layer.

15. A method for evaluating a structure of a polarizing plate, comprising:

providing a polarizing plate composite layer, wherein the polarizing plate composite layer comprises a polarizer and a first protective layer positioned on the first surface of the polarizer, and the first protective layer is provided with a rough surface far away from the polarizer;

measuring an initial haze value of the first protective layer;

disposing a first adhesive layer on the rough surface of the first passivation layer;

arranging a first covering layer on the first adhesive layer, wherein the polarizing plate composite layer, the first adhesive layer and the first covering layer form the polarizing plate structure; and

measuring a bonding haze value of the first protective layer provided with the first adhesive layer and the first covering layer, and obtaining a difference value between the bonding haze value and the initial haze value, wherein the percentage of the difference value relative to the initial haze value is a haze value change rate,

wherein the haze value change rate is 80% or more, and the adhesion state of the first adhesive layer and the rough surface of the first protective layer is evaluated as good.