CN113567283A - Method for evaluating surface protective film - Google Patents
Method for evaluating surface protective film Download PDFInfo
- Publication number
- CN113567283A CN113567283A CN202110744408.XA CN202110744408A CN113567283A CN 113567283 A CN113567283 A CN 113567283A CN 202110744408 A CN202110744408 A CN 202110744408A CN 113567283 A CN113567283 A CN 113567283A
- Authority
- CN
- China
- Prior art keywords
- protective film
- surface protective
- stiffness
- evaluating
- moire
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 230000001681 protective effect Effects 0.000 title claims abstract description 132
- 238000000034 method Methods 0.000 title claims abstract description 32
- 238000005259 measurement Methods 0.000 claims abstract description 20
- 238000003825 pressing Methods 0.000 claims abstract description 11
- 229920005989 resin Polymers 0.000 claims description 35
- 239000011347 resin Substances 0.000 claims description 35
- 239000000463 material Substances 0.000 claims description 34
- 238000011156 evaluation Methods 0.000 claims description 19
- 239000000758 substrate Substances 0.000 claims description 18
- 229920002678 cellulose Polymers 0.000 claims description 15
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 claims description 13
- 239000001913 cellulose Substances 0.000 claims description 13
- 238000007689 inspection Methods 0.000 claims description 9
- 239000007779 soft material Substances 0.000 claims description 9
- 229920005672 polyolefin resin Polymers 0.000 claims description 8
- 238000006243 chemical reaction Methods 0.000 claims description 6
- 229920000515 polycarbonate Polymers 0.000 claims description 6
- 239000004417 polycarbonate Substances 0.000 claims description 6
- 229920001225 polyester resin Polymers 0.000 claims description 3
- 230000000149 penetrating effect Effects 0.000 claims description 2
- 238000009864 tensile test Methods 0.000 claims 1
- 239000010408 film Substances 0.000 description 190
- 206010052904 Musculoskeletal stiffness Diseases 0.000 description 67
- 239000000523 sample Substances 0.000 description 52
- -1 polyethylene Terephthalate Polymers 0.000 description 17
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 12
- 229920002284 Cellulose triacetate Polymers 0.000 description 11
- NNLVGZFZQQXQNW-ADJNRHBOSA-N [(2r,3r,4s,5r,6s)-4,5-diacetyloxy-3-[(2s,3r,4s,5r,6r)-3,4,5-triacetyloxy-6-(acetyloxymethyl)oxan-2-yl]oxy-6-[(2r,3r,4s,5r,6s)-4,5,6-triacetyloxy-2-(acetyloxymethyl)oxan-3-yl]oxyoxan-2-yl]methyl acetate Chemical compound O([C@@H]1O[C@@H]([C@H]([C@H](OC(C)=O)[C@H]1OC(C)=O)O[C@H]1[C@@H]([C@@H](OC(C)=O)[C@H](OC(C)=O)[C@@H](COC(C)=O)O1)OC(C)=O)COC(=O)C)[C@@H]1[C@@H](COC(C)=O)O[C@@H](OC(C)=O)[C@H](OC(C)=O)[C@H]1OC(C)=O NNLVGZFZQQXQNW-ADJNRHBOSA-N 0.000 description 11
- 239000010410 layer Substances 0.000 description 10
- 229920000139 polyethylene terephthalate Polymers 0.000 description 8
- 239000005020 polyethylene terephthalate Substances 0.000 description 8
- 239000004698 Polyethylene Substances 0.000 description 7
- 239000012790 adhesive layer Substances 0.000 description 7
- 229920000573 polyethylene Polymers 0.000 description 7
- 238000012360 testing method Methods 0.000 description 7
- JOYRKODLDBILNP-UHFFFAOYSA-N Ethyl urethane Chemical compound CCOC(N)=O JOYRKODLDBILNP-UHFFFAOYSA-N 0.000 description 6
- 239000004743 Polypropylene Substances 0.000 description 6
- 239000004372 Polyvinyl alcohol Substances 0.000 description 6
- 239000004820 Pressure-sensitive adhesive Substances 0.000 description 6
- 229920001577 copolymer Polymers 0.000 description 6
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 6
- 229920001155 polypropylene Polymers 0.000 description 6
- 229920002451 polyvinyl alcohol Polymers 0.000 description 6
- 229920000089 Cyclic olefin copolymer Polymers 0.000 description 4
- XTXRWKRVRITETP-UHFFFAOYSA-N Vinyl acetate Chemical compound CC(=O)OC=C XTXRWKRVRITETP-UHFFFAOYSA-N 0.000 description 4
- ZSWFCLXCOIISFI-UHFFFAOYSA-N cyclopentadiene Chemical compound C1C=CC=C1 ZSWFCLXCOIISFI-UHFFFAOYSA-N 0.000 description 4
- 229920005994 diacetyl cellulose Polymers 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 239000000178 monomer Substances 0.000 description 4
- 230000003287 optical effect Effects 0.000 description 4
- 229920003229 poly(methyl methacrylate) Polymers 0.000 description 4
- 239000004926 polymethyl methacrylate Substances 0.000 description 4
- 239000000853 adhesive Substances 0.000 description 3
- 230000001070 adhesive effect Effects 0.000 description 3
- 150000001336 alkenes Chemical class 0.000 description 3
- 239000011521 glass Substances 0.000 description 3
- 239000012788 optical film Substances 0.000 description 3
- 229920001296 polysiloxane Polymers 0.000 description 3
- 229920002689 polyvinyl acetate Polymers 0.000 description 3
- 239000011118 polyvinyl acetate Substances 0.000 description 3
- HECLRDQVFMWTQS-RGOKHQFPSA-N 1755-01-7 Chemical compound C1[C@H]2[C@@H]3CC=C[C@@H]3[C@@H]1C=C2 HECLRDQVFMWTQS-RGOKHQFPSA-N 0.000 description 2
- 239000004925 Acrylic resin Substances 0.000 description 2
- 229920000178 Acrylic resin Polymers 0.000 description 2
- 229930185605 Bisphenol Natural products 0.000 description 2
- 229920008347 Cellulose acetate propionate Polymers 0.000 description 2
- 239000004593 Epoxy Substances 0.000 description 2
- 206010052128 Glare Diseases 0.000 description 2
- 239000004721 Polyphenylene oxide Substances 0.000 description 2
- SMEGJBVQLJJKKX-HOTMZDKISA-N [(2R,3S,4S,5R,6R)-5-acetyloxy-3,4,6-trihydroxyoxan-2-yl]methyl acetate Chemical compound CC(=O)OC[C@@H]1[C@H]([C@@H]([C@H]([C@@H](O1)O)OC(=O)C)O)O SMEGJBVQLJJKKX-HOTMZDKISA-N 0.000 description 2
- 229940081735 acetylcellulose Drugs 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 230000004888 barrier function Effects 0.000 description 2
- IISBACLAFKSPIT-UHFFFAOYSA-N bisphenol A Chemical compound C=1C=C(O)C=CC=1C(C)(C)C1=CC=C(O)C=C1 IISBACLAFKSPIT-UHFFFAOYSA-N 0.000 description 2
- BVKZGUZCCUSVTD-UHFFFAOYSA-N carbonic acid Chemical compound OC(O)=O BVKZGUZCCUSVTD-UHFFFAOYSA-N 0.000 description 2
- 229920002301 cellulose acetate Polymers 0.000 description 2
- 229920006217 cellulose acetate butyrate Polymers 0.000 description 2
- 125000004122 cyclic group Chemical group 0.000 description 2
- 238000013016 damping Methods 0.000 description 2
- 150000002009 diols Chemical class 0.000 description 2
- 150000002148 esters Chemical class 0.000 description 2
- FJKIXWOMBXYWOQ-UHFFFAOYSA-N ethenoxyethane Chemical compound CCOC=C FJKIXWOMBXYWOQ-UHFFFAOYSA-N 0.000 description 2
- 238000003475 lamination Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000000691 measurement method Methods 0.000 description 2
- JFNLZVQOOSMTJK-KNVOCYPGSA-N norbornene Chemical compound C1[C@@H]2CC[C@H]1C=C2 JFNLZVQOOSMTJK-KNVOCYPGSA-N 0.000 description 2
- JRZJOMJEPLMPRA-UHFFFAOYSA-N olefin Natural products CCCCCCCC=C JRZJOMJEPLMPRA-UHFFFAOYSA-N 0.000 description 2
- 229920000636 poly(norbornene) polymer Polymers 0.000 description 2
- 229920000728 polyester Polymers 0.000 description 2
- 229920000570 polyether Polymers 0.000 description 2
- 229920000642 polymer Polymers 0.000 description 2
- 229920000193 polymethacrylate Polymers 0.000 description 2
- 238000002203 pretreatment Methods 0.000 description 2
- 230000002265 prevention Effects 0.000 description 2
- 239000011241 protective layer Substances 0.000 description 2
- 238000011084 recovery Methods 0.000 description 2
- 238000007142 ring opening reaction Methods 0.000 description 2
- 238000004381 surface treatment Methods 0.000 description 2
- XBFJAVXCNXDMBH-UHFFFAOYSA-N tetracyclo[6.2.1.1(3,6).0(2,7)]dodec-4-ene Chemical compound C1C(C23)C=CC1C3C1CC2CC1 XBFJAVXCNXDMBH-UHFFFAOYSA-N 0.000 description 2
- 229920005992 thermoplastic resin Polymers 0.000 description 2
- 229920001187 thermosetting polymer Polymers 0.000 description 2
- ILJSQTXMGCGYMG-UHFFFAOYSA-N triacetic acid Chemical compound CC(=O)CC(=O)CC(O)=O ILJSQTXMGCGYMG-UHFFFAOYSA-N 0.000 description 2
- OVGRCEFMXPHEBL-UHFFFAOYSA-N 1-ethenoxypropane Chemical compound CCCOC=C OVGRCEFMXPHEBL-UHFFFAOYSA-N 0.000 description 1
- SMZOUWXMTYCWNB-UHFFFAOYSA-N 2-(2-methoxy-5-methylphenyl)ethanamine Chemical compound COC1=CC=C(C)C=C1CCN SMZOUWXMTYCWNB-UHFFFAOYSA-N 0.000 description 1
- GNUGVECARVKIPH-UHFFFAOYSA-N 2-ethenoxypropane Chemical compound CC(C)OC=C GNUGVECARVKIPH-UHFFFAOYSA-N 0.000 description 1
- ZCYVEMRRCGMTRW-UHFFFAOYSA-N 7553-56-2 Chemical compound [I] ZCYVEMRRCGMTRW-UHFFFAOYSA-N 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-M Acrylate Chemical compound [O-]C(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-M 0.000 description 1
- JIGUQPWFLRLWPJ-UHFFFAOYSA-N Ethyl acrylate Chemical compound CCOC(=O)C=C JIGUQPWFLRLWPJ-UHFFFAOYSA-N 0.000 description 1
- 244000043261 Hevea brasiliensis Species 0.000 description 1
- VQTUBCCKSQIDNK-UHFFFAOYSA-N Isobutene Chemical compound CC(C)=C VQTUBCCKSQIDNK-UHFFFAOYSA-N 0.000 description 1
- CERQOIWHTDAKMF-UHFFFAOYSA-N Methacrylic acid Chemical compound CC(=C)C(O)=O CERQOIWHTDAKMF-UHFFFAOYSA-N 0.000 description 1
- VVQNEPGJFQJSBK-UHFFFAOYSA-N Methyl methacrylate Chemical compound COC(=O)C(C)=C VVQNEPGJFQJSBK-UHFFFAOYSA-N 0.000 description 1
- QYKIQEUNHZKYBP-UHFFFAOYSA-N Vinyl ether Chemical class C=COC=C QYKIQEUNHZKYBP-UHFFFAOYSA-N 0.000 description 1
- 150000001252 acrylic acid derivatives Chemical class 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 230000002238 attenuated effect Effects 0.000 description 1
- 229920001400 block copolymer Polymers 0.000 description 1
- 150000001735 carboxylic acids Chemical class 0.000 description 1
- 239000012876 carrier material Substances 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 150000001925 cycloalkenes Chemical class 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 229920001971 elastomer Polymers 0.000 description 1
- 239000003822 epoxy resin Substances 0.000 description 1
- 229920001519 homopolymer Polymers 0.000 description 1
- 239000011630 iodine Substances 0.000 description 1
- 229910052740 iodine Inorganic materials 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 125000005395 methacrylic acid group Chemical group 0.000 description 1
- XJRBAMWJDBPFIM-UHFFFAOYSA-N methyl vinyl ether Chemical compound COC=C XJRBAMWJDBPFIM-UHFFFAOYSA-N 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229920003052 natural elastomer Polymers 0.000 description 1
- 229920001194 natural rubber Polymers 0.000 description 1
- 239000005026 oriented polypropylene Substances 0.000 description 1
- PNJWIWWMYCMZRO-UHFFFAOYSA-N pent‐4‐en‐2‐one Natural products CC(=O)CC=C PNJWIWWMYCMZRO-UHFFFAOYSA-N 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003207 poly(ethylene-2,6-naphthalate) Polymers 0.000 description 1
- 229920005668 polycarbonate resin Polymers 0.000 description 1
- 239000004431 polycarbonate resin Substances 0.000 description 1
- 229920000647 polyepoxide Polymers 0.000 description 1
- 239000011112 polyethylene naphthalate Substances 0.000 description 1
- 229920000098 polyolefin Polymers 0.000 description 1
- 229920001289 polyvinyl ether Polymers 0.000 description 1
- 238000007781 pre-processing Methods 0.000 description 1
- PNXMTCDJUBJHQJ-UHFFFAOYSA-N propyl prop-2-enoate Chemical compound CCCOC(=O)C=C PNXMTCDJUBJHQJ-UHFFFAOYSA-N 0.000 description 1
- 239000005060 rubber Substances 0.000 description 1
- 229920002050 silicone resin Polymers 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- BWYYYTVSBPRQCN-UHFFFAOYSA-M sodium;ethenesulfonate Chemical compound [Na+].[O-]S(=O)(=O)C=C BWYYYTVSBPRQCN-UHFFFAOYSA-M 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 229920006132 styrene block copolymer Polymers 0.000 description 1
- 150000003460 sulfonic acids Chemical class 0.000 description 1
- 229920003051 synthetic elastomer Polymers 0.000 description 1
- 239000005061 synthetic rubber Substances 0.000 description 1
- 229920002725 thermoplastic elastomer Polymers 0.000 description 1
- 150000003673 urethanes Chemical class 0.000 description 1
- NLVXSWCKKBEXTG-UHFFFAOYSA-N vinylsulfonic acid Chemical compound OS(=O)(=O)C=C NLVXSWCKKBEXTG-UHFFFAOYSA-N 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/40—Investigating hardness or rebound hardness
- G01N3/42—Investigating hardness or rebound hardness by performing impressions under a steady load by indentors, e.g. sphere, pyramid
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/02—Details
- G01N3/06—Special adaptations of indicating or recording means
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/02—Details
- G01N3/06—Special adaptations of indicating or recording means
- G01N3/068—Special adaptations of indicating or recording means with optical indicating or recording means
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/08—Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/0001—Type of application of the stress
- G01N2203/0003—Steady
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/0014—Type of force applied
- G01N2203/0016—Tensile or compressive
- G01N2203/0017—Tensile
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/0058—Kind of property studied
- G01N2203/0076—Hardness, compressibility or resistance to crushing
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/06—Indicating or recording means; Sensing means
- G01N2203/0641—Indicating or recording means; Sensing means using optical, X-ray, ultraviolet, infrared or similar detectors
- G01N2203/0647—Image analysis
Landscapes
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Polarising Elements (AREA)
- Testing Resistance To Weather, Investigating Materials By Mechanical Methods (AREA)
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
The present disclosure provides a method for evaluating a surface protection film, comprising: the measurement step of the stiffness attenuation rate comprises the following steps: after the surface protection film is curled into a cylindrical sample, the cylindrical sample is fixed on a clamp, wherein the cylindrical sample has a first height; pressing the cylindrical sample to a second height, and measuring the change of the stiffness of the surface protection film along with the time; and calculating a stiffness attenuation ratio of the surface protective film from a change in stiffness of the surface protective film with time; and evaluating the anti-moire property of the surface protective film by using the stiffness attenuation rate of the surface protective film as an index.
Description
Technical Field
The present disclosure relates to a method for evaluating a surface protection film, and more particularly, to an anti-mura (anti-mura) evaluation method for a surface protection film.
Background
The polarizing film is an optical element widely used in displays, and as the applications of displays are wider, for example, mobile phones, wearable devices, etc., the requirements for the quality of the polarizing film are also higher. After the polarizing film is manufactured, the polarizing film is usually attached to displays of various sizes with a surface protection film and then the surface protection film is removed, so that no effort is made in the industry to improve the quality of the surface protection film.
Disclosure of Invention
In order to solve the above problems, the present disclosure provides a method for evaluating a surface protection film, comprising: the measurement step of the stiffness attenuation rate comprises the following steps: after the surface protection film is curled into a cylindrical sample, the cylindrical sample is fixed on a clamp, wherein the cylindrical sample has a first height; pressing the cylindrical sample to a second height, and measuring the change of the stiffness of the surface protection film along with the time; and calculating a stiffness attenuation ratio of the surface protective film from a change in stiffness of the surface protective film with time; and evaluating the anti-moire property of the surface protective film by using the stiffness attenuation rate of the surface protective film as an index.
Drawings
The embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. It should be noted that, in accordance with standard practice in the industry, the various features are not drawn to scale and are merely illustrative. In fact, the dimensions of the elements may be arbitrarily increased or reduced to clearly illustrate the features of the embodiments of the present disclosure.
FIG. 1 is a schematic diagram illustrating a step of measuring a rate of attenuation of stiffness of a surface protective film according to some embodiments;
FIG. 2 is a chart illustrating actual measurements of surface protection film stiffness versus time, according to one embodiment;
FIGS. 3A and 3B are images of the results of a lighting check performed on a panel, according to some embodiments;
fig. 4A and 4B are schematic diagrams illustrating a deformation rate measuring step of the surface protection film according to some embodiments.
[ notation ] to show
102 sample (cylindrical sample)
104,404 clamping apparatus
104-1: lower part
104-2: upper part
302 polarizing plate
304 display panel
306 backlight module
308 camera
402 sample
A stiffness attenuation zone
D is distance
h1 first height
h2 second height
L is light
L0 original Long edge Length
L1 Length of Long side after stretching
S1, S2, S3, S4
W0 original short edge length
W1 length of short side after stretching
Detailed Description
The following disclosure provides many different embodiments, or examples, for illustrating different components of embodiments of the invention. Specific examples of components and arrangements thereof are disclosed below to simplify the present disclosure. Of course, these specific examples are not intended to be limiting of the disclosure. For example, the following summary of the present specification describes forming a first feature over or on a second feature, i.e., embodiments in which the formed first and second features are in direct contact, and embodiments in which additional features may be formed between the first and second features, i.e., the first and second features are not in direct contact. Moreover, various examples of the present disclosure may use repeated reference characters and/or words. These repeated symbols or words are provided for simplicity and clarity and are not intended to limit the relationship between the various embodiments and/or the described configurations.
Also, spatially relative terms, such as "under …," "below," "lower," "above," "upper," and the like, may be used herein for convenience in describing the relationship of one element or component to another element(s) or component(s) in the figures. Spatially relative terms may encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. When the device is turned to a different orientation (e.g., rotated 90 degrees or otherwise), the spatially relative adjectives used herein will also be interpreted in terms of the turned orientation.
As used herein, the term "about", "about" or "substantially" generally means within 20%, preferably within 10%, and more preferably within 5%, or within 3%, or within 2%, or within 1%, or within 0.5% of a given value or range. It should be noted that the amounts provided in the specification are approximate amounts, i.e., the meanings of "about", "about" and "about" may be implied without specific recitation of "about", "about" and "about".
The production efficiency of the product based on the polarizing plate (after the surface protection film is attached) is very important for the warpage degree, and if the product has a negative warpage problem (i.e. the polarizing plate is warped towards the side far away from the surface protection film), it is easy to cause the user to be unable to smoothly attach the polarizing plate to the glass substrate. In order to avoid the negative warpage problem of the polarizing plate product, the warpage can be adjusted to be positive warpage (i.e., the side of the polarizing plate facing the surface protection film) during the manufacturing process of the polarizing plate, and the warpage adjustment is usually achieved by increasing the tension on the surface protection film.
However, the increased tension may cause the surface protection film to be deformed due to extension, and the deformation recovery may occur after time, thereby causing the stiffness of the surface protection film to be attenuated, so that the manufactured panel may easily generate moire (mura), wherein the moire is uneven brightness and chromaticity of the panel, which may hinder the performance of the display. In addition, the surface protection film may slide in the process of deformation recovery, and the surface protection film may deform and have uneven thickness due to increased tension of the surface protection film, which may also easily cause the moire of the panel.
Embodiments of the present invention provide a method for evaluating a surface protective film for a polarizing plate, which includes a step of measuring a stiffness attenuation ratio, and evaluates anti-moire characteristics of the surface protective film using the stiffness attenuation ratio of the surface protective film as an index, and embodiments of a measurement method of the stiffness attenuation ratio will be described in further detail below. It should be understood that the measurement method of the stiffness attenuation ratio disclosed in the present invention is not limited to the following parameters, and those skilled in the art can freely adjust the parameters used in the stiffness attenuation ratio measurement step.
The sample pretreatment may be performed before the step of measuring the rate of attenuation of stiffness of the surface protective film according to the present disclosure. In sample pre-processing of some embodiments, a cut surface protection film (e.g., 30cm in length and 20cm in width) may be first attached to a soft material of the same size by using a roller of an appropriate weight (e.g., 2kg) to form an attached surface protection film sample. After the completion of the bonding, the sample can be placed in an environment at a temperature of 25 ℃ and a humidity of 55% for 1 day to make the bonding of the surface protective film and the soft material more firm, and before the step of measuring the attenuation rate of stiffness of the surface protective film, the bonded surface protective film and the soft material are cut into appropriate sizes, for example, a size of 170mm in length and 15mm in width, to obtain a sample for measuring the attenuation rate of stiffness. It should be understood that other sizes of surface protective films and soft materials may be used in the sample pre-treatment described above.
The material of the surface protective film is not particularly limited, and the material of the surface protective film may be a thermoplastic resin excellent in transparency, mechanical strength, thermal stability, moisture barrier property, and the like, and may include, for example, a cellulose-based resin, an acrylic-based resin, a noncrystalline polyolefin-based resin, a polyester-based resin, a polycarbonate-based resin, or any combination thereof. The cellulose-based resin is a resin in which a part of hydroxyl groups in cellulose is esterified with acetic acid, or a mixed ester in which a part of hydroxyl groups is esterified with acetic acid and a part is esterified with another acid. The cellulose-based resin is preferably a cellulose ester-based resin, more preferably an acetyl cellulose-based resin, such as triacetyl cellulose, diacetyl cellulose, cellulose acetate propionate, cellulose acetate butyrate, and the like. The cellulose which is sufficiently esterified is called triacetate cellulose (TAC), acrylic resin film, polyaromatic hydroxyl resin film, polyether resin film, cyclic polyolefin resin film (for example, polynorbornene resin film). The polycarbonate-series resin is, for example, a polyester formed from carbonic acid and a diol or bisphenol, such as polyethylene Terephthalate (PET), polypropylene (PP), Polyethylene (PE). The noncrystalline polyolefin resin is, for example, a group consisting of cyclic olefin monomer (co) polymers (COC/COP), ring-opening polymers of norbornene, cyclopentadiene, dicyclopentadiene, tetracyclododecene, or copolymers with olefins, Polycarbonate (PC), and any combinations thereof. In addition, the protective layer material may be a thermosetting resin or an ultraviolet-curable resin such as (meth) acrylic, urethane, acrylic urethane, epoxy, or silicone. Further, the material of the surface protective film may be subjected to a surface treatment such as an anti-glare treatment, an anti-reflection treatment, a hard coat treatment, a charge prevention treatment, or an anti-stain treatment.
The flexible material may be a single layer or a multilayer optical film. The material of the soft material is not particularly limited, and the material of the soft material may include Triacetylcellulose (TAC), Diacetylcellulose (DAC), polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), polyethylene naphthalate, olefin resin, polycarbonate resin (PC), cycloolefin resin, oriented polypropylene (OPP), Polyethylene (PE), polypropylene (PP), cycloolefin polymer (COP), cycloolefin copolymer (COC), urethane (PU), acrylic urethane, epoxy resin, silicone resin, or any combination thereof.
In a specific embodiment, the material of the surface protective film may include polymethyl methacrylate, and the material of the soft material may include cellulose triacetate.
In a specific embodiment, the material of the surface protection film may include polymethyl methacrylate, and the flexible material may be a multilayer optical film, which is bonded to the surface protection film to form a polarizer. In some embodiments, the polarizer may include various layers, for example, from top to bottom: a surface protection film, an adhesive layer, a first protection layer (such as triacetyl cellulose film), a polyvinyl alcohol film as a polarizing material, a second protection layer (such as triacetyl cellulose film), an adhesive layer, a release film, etc., but the structure of the present disclosure is not limited thereto, and for example, the first and/or second protection layers may be omitted, or other common materials may be used.
In some embodiments, the adhesive layer includes a Pressure Sensitive Adhesive (PSA), a heat sensitive adhesive, a solvent volatile adhesive, and a UV curable adhesive. In some embodiments, the pressure sensitive adhesive comprises natural rubber, synthetic rubber, styrenic block copolymers, (meth) acrylic block copolymers, polyvinyl ethers, polyolefins, and poly (meth) acrylates. In some embodiments, (meth) acrylic (or acrylate) refers to both acrylic and methacrylic. In other embodiments, the pressure sensitive adhesive comprises (meth) acrylates, rubbers, thermoplastic elastomers, silicones, urethanes, and combinations thereof. In some embodiments, the pressure sensitive adhesive is based on a (meth) acrylic pressure sensitive adhesive or on at least one poly (meth) acrylate.
Referring next to fig. 1, fig. 1 is a schematic diagram illustrating a step of measuring a stiffness attenuation ratio of a surface protection film according to some embodiments. First, in step S1, a sample 102 of a surface protective film to which a soft material is attached is rolled into a cylindrical shape having, for example, an elliptical cross section, and the sample 102 is fixed to a lower portion 104-1 of a jig 104 of a tensile machine, wherein the cylindrical sample 102 has a first height h1, and the first height h1 is, for example, in the range of 50 to 90 mm. In some embodiments, where sample 102 is 170mm in length, first height h1 may be, for example, 80 mm. Next, in step S2, the upper part 104-2 of the jig is moved down to touch the cylindrical sample 102, and the cylindrical sample 102 is maintained at the first height h 1.
Next, in step S3, the pressing of the cylindrical sample 102 is started at a pressing speed of, for example, 130mm/min, and the pressing is stopped until the cylindrical sample 102 has a second height h2, and the change in stiffness of the surface protection film over time is measured, wherein the second height is, for example, in the range of 5 to 60 mm. With respect to the selection of the second height h2, if the second height is too large, the amount of deformation of the sample will be small, and the difference in properties of the samples will be too small to be recognized although the samples will still suffer from stiffness degradation; on the other hand, if the second height is too small, the amount of deformation of the sample is large, but the sample may be broken to make the data difficult to interpret. In some embodiments, where sample 102 is 170mm in length, second height h2 may be, for example, 15 mm. Next, in step S4 (not shown), the measurement is stopped after a decrease in the stiffness of the surface protective film is observed for a certain period of time, and the rate of attenuation in stiffness of the surface protective film is calculated using the change in stiffness of the surface protective film over time. In one embodiment, the measurement time of the change in stiffness after the decrease in stiffness of the surface protective film is observed (stiffness decay time) in step S4 may be, for example, 1 to 5 seconds.
Fig. 2 is a graph illustrating an actual measurement of surface protective film stiffness versus time, according to one embodiment. In this example, the cylindrical sample was pressed at a pressing speed of 130mm/min, and stopped after pressing down the cylindrical sample from a first height of 80mm to a second height of 15 mm. As shown in fig. 2, the surface protective film reached a maximum stiffness M of about 350N/25mm corresponding to the second height about 30 seconds after the start of the pressing down, and then the pressing down was stopped. Referring to the stiffness attenuation zone a of fig. 2, the surface protective film starts stiffness attenuation after undergoing the maximum stiffness M, attenuates from about 350N/25mm at the maximum stiffness M to about 250N/25mm after 5 seconds, and the stiffness of the surface protective film is measured as it attenuates with time. In some embodiments, as shown in FIG. 2, the measurement time is, for example, 5 seconds.
The rate of attenuation in stiffness of the surface protective film is calculated by the following formula (1):
formula (1): the attenuation ratio of stiffness (maximum stiffness-stiffness after reaction) ÷ maximum stiffness
Wherein the post-reaction stiffness is the stiffness taken as n seconds after the maximum stiffness is produced, and n can be, for example, 1 to 5. For example, in the embodiment of fig. 2, the attenuation of stiffness calculated from the stiffness taken at 5 seconds (about 250mN/25mm) after the maximum stiffness M (about 350mN/25mm) is (350-.
As the anti-moire performance of the surface protection film, whether the panel made of the surface protection film has the moire is evaluated, and the step of evaluating the moire comprises the following steps: first, a surface protective film may be attached to a polarizing film, which is a film for converting light passing therethrough (polarized light having any direction) into polarized light having a specific direction. The polarizing film may be a known metal polarizing film, iodine polarizing film, dye polarizing film, polyethylene polarizing film, or the like. The material of the polarizing film may be a polyvinyl alcohol (PVA) resin film, which 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.
The polarizing film material is prepared by using an integrated layer composed of other optical film layers such as a polyvinyl alcohol (PVA) film, and then, referring to fig. 3A, the polarizing plate 302 is attached to a display panel 304 (hereinafter collectively referred to as a panel) to which a backlight module 306 as a light emitting source is attached at the rear of the display panel 304. In some embodiments, the polarizer may include various layers, for example, from top to bottom: the present disclosure is not limited to the above-mentioned examples, and the polarizer may be a surface protection film, an adhesive layer, a first protection layer (such as a triacetyl cellulose film), a polyvinyl alcohol film as a polarizing material, a second protection layer (such as a triacetyl cellulose film), an adhesive layer, a release film (release film), or the like.
After the polarizer 302 is attached to the display panel 304, the light-emitting module 306 emits a light source for lighting inspection, and the camera 308 disposed at a distance D (e.g., about 1 m) in front of the polarizer 302 and the display panel 304 is used to capture an image of the light source penetrating through the polarizer 302 and confirm a position where the chromaticity (or brightness) is not uniform and a position where the chromaticity is uniform in the image.
Regarding the comparison method of RGB color codes, fig. 3B is first referred to. Fig. 3B is an image of the result of the lighting inspection of the panel according to some embodiments, in which light with uneven brightness is observed to penetrate through the polarizing plate, thereby finding out RGB color codes with uneven brightness and uniform brightness, and the positions where the RGB color codes have the maximum value and the minimum value are respectively defined as a brightness unevenness position P1 (the RGB color codes are R1, G1, and B1) and a brightness uniformity position P2 (the RGB color codes are R2, G2, and B2), where the values of the RGB color codes are: v ((R)2+(G)2+(B)2) Wherein R, G, B are the RGB color codes at the luminance measurement, respectively. Next, the luminance unevenness of the panel is calculated by the following formula (2):
formula (2): brightness unevenness ═ v ((R1-R2)2+(G1－G2)2+(B1－B2)2)
The evaluation of the panel moire was based on the following criteria: severe (X), mild (Δ), and normal (O). The above reference is defined by the luminance unevenness of the panel, and for example, when the luminance unevenness of the panel is 110 or more, the evaluation result of the panel moire may be defined as serious (X), that is, moire is easily generated; defining the evaluation result of the panel moire to be slight (delta) when the brightness unevenness of the panel is 50-110, namely generating a little moire in an acceptable range; when the luminance unevenness of the panel is 50 or less, the evaluation result of the panel moire is defined as normal (O), that is, no moire is generated.
The following test of the attenuation rate of stiffness was performed for various samples of the surface protective film material for a polarizing plate, in which the stiffness taken at the time of 1 second, 3 seconds, and 5 seconds after the maximum stiffness was generated was used as the post-reaction stiffness, respectively, for calculating the attenuation rate of stiffness. Then, a lighting inspection was performed on the panel including the above-mentioned various surface protective film materials, and whether or not moire occurred was observed, and the results of the stiffness attenuation ratio test and the lighting inspection were compared. The results are shown in table 1 below. Thereby, the anti-moire property of the surface protective film can be evaluated using the stiffness attenuation rate of the surface protective film as an index.
TABLE 1
As can be seen from table 1, the panel produced from the surface protective film sample having a low stiffness attenuation ratio has low luminance unevenness and is less likely to generate moire. As can be confirmed from the test results in table 1, when the stiffness values taken at the time of 1 second, 3 seconds, and 5 seconds after the generation of the maximum stiffness value are used as the post-reaction stiffness values to calculate the stiffness attenuation ratios, the panel manufactured by the surface protective film samples having the stiffness attenuation ratios of 1.3%, 2.7%, and 4.4% or less, respectively, had a luminance unevenness of 50 or less, and thus had a normal (O) moire evaluation result, without a problem of luminance unevenness, i.e., without generation of moire; since the panels manufactured by the surface protective film samples having 1.4%, 2.9%, and 4.7% or more of the damping rate had a brightness unevenness of 50% or more, it was confirmed that the light having a serious (X) or slight (Δ) moire evaluation was transmitted through the panel, that is, the panel manufactured by the surface protective film sample having a high damping rate was likely to have moire. According to the moire evaluation result, the surface protection film sample has a stiffness attenuation rate of less than 4.7 percent and is not easy to generate moire; the better surface protection film sample has the stiffness attenuation rate of less than 4.4 percent, does not generate moire and has better anti-moire characteristics.
As described above, the present disclosure provides a method for evaluating a surface protective film, which includes a step of measuring a stiffness attenuation ratio to obtain a stiffness attenuation ratio of the surface protective film, and uses the stiffness attenuation ratio as an index for evaluating anti-moire characteristics of various surface protective film samples. Therefore, the anti-moire evaluation method can be used for evaluating whether the surface protection film material for the polarizing plate is easy to generate the moire phenomenon of uneven brightness after the optical display device is manufactured.
In addition to using the stiffness attenuation rate as an index of the anti-moire property of the surface protection film, the surface protection film is deformed and restored after being extended to cause the sliding phenomenon of the surface protection film and the deformation of the polarizing plate, so that the manufactured panel is prone to generate moire, and the brightness of the display is uneven. In order to reduce the deformation of the polarizing plate, a surface protective film having low slidability is required. Therefore, in some embodiments, a slip amount measuring step may be further added to the evaluation method of the surface protective film, and the anti-moire property of the surface protective film may be evaluated using the slip amount of the surface protective film with respect to the substrate as an index. An example of the manner of measuring the slip amount will be described in further detail below. It should be understood that the measurement of the slip disclosed herein is not limited to the following parameters, and those skilled in the art can freely adjust the parameters used in the slip measurement step.
Before the slip measurement step of the surface protection film disclosed by the present disclosure, a sample pretreatment may be performed. In some embodiments, the sample pre-treatment may be performed by first attaching a polarizer (e.g., 15cm in length and 5cm in width) without a surface protection film to a carrier, wherein the carrier is made of a carrier material such as glass or plastic, and serves as a substrate for measuring the amount of slip. Next, a surface protective film (length 15cm, width 2.5cm) was bonded to the surface of the substrate via an adhesive layer using a roller of an appropriate weight (for example, 2 kg). In one embodiment, the surface protection film and the polarizer may be bonded together by an adhesive layer, and then bonded to the surface of the substrate. The material of the adhesion layer is the same as that disclosed in the previous section of this specification, and is not described herein again.
In one embodiment, the surface protection film has an area smaller than or equal to the surface of the substrate and/or the polarizer. The material of the surface protective film is not particularly limited, and the material of the surface protective film may be a thermoplastic resin excellent in transparency, mechanical strength, thermal stability, moisture barrier property, and the like, and may include, for example, a cellulose-based resin, an acrylic-based resin, a noncrystalline polyolefin-based resin, a polyester-based resin, a polycarbonate-based resin, or any combination thereof. The cellulose-based resin is a resin in which a part of hydroxyl groups in cellulose is esterified with acetic acid, or a mixed ester in which a part of hydroxyl groups is esterified with acetic acid and a part is esterified with another acid. The cellulose-based resin is preferably a cellulose ester-based resin, more preferably an acetyl cellulose-based resin, such as triacetyl cellulose, diacetyl cellulose, cellulose acetate propionate, cellulose acetate butyrate, and the like. The cellulose which is sufficiently esterified is called triacetate cellulose (TAC), acrylic resin film, polyaromatic hydroxyl resin film, polyether resin film, cyclic polyolefin resin film (for example, polynorbornene resin film). The polycarbonate-series resin is, for example, a polyester formed from carbonic acid and a diol or bisphenol, such as polyethylene Terephthalate (PET), polypropylene (PP), Polyethylene (PE). The noncrystalline polyolefin resin is, for example, a group consisting of cyclic olefin monomer (co) polymers (COC/COP), ring-opening polymers of norbornene, cyclopentadiene, dicyclopentadiene, tetracyclododecene, or copolymers with olefins, Polycarbonate (PC), and any combinations thereof. In addition, the protective layer material may be a thermosetting resin or an ultraviolet-curable resin such as (meth) acrylic, urethane, acrylic urethane, epoxy, or silicone. Further, the material of the surface protective film may be subjected to a surface treatment such as an anti-glare treatment, an anti-reflection treatment, a hard coat treatment, a charge prevention treatment, or an anti-stain treatment.
In a specific embodiment, polyethylene terephthalate (PET) may be used as a material of the surface protective film. After the lamination, the sample can be placed in an environment with the temperature of 25 ℃ and the humidity of 55% for 1 day, so that the lamination between the surface protection film and the polarizing plate and the substrate is firmer to form the sample for measuring the slippage. It should be understood that other sizes of surface protective films, polarizing plates, and glass may be used for the measurement side in the sample pretreatment described above.
Regarding the slip amount measuring step of the surface protective film, in some embodiments, a tensile tester (e.g., shimadzu tensile AGX tester) is used to stretch the surface protective film sample. The surface protective film is first fixed on a tensile tester and the position of the surface protective film is recorded, then the surface protective film is stretched for a fixed time at a fixed tension, and the slippage of the surface protective film relative to the surface of the substrate and/or the polarizing plate is measured. In some embodiments, the stretching conditions are: stretching the sheet under a tension of 10 to 60N for 0.5 to 3 hours. In some embodiments, the slippage of the surface protection film relative to the surfaces of the substrate and the polarizing plate is the same, that is, only the surface protection film slips relative to the surfaces of the substrate and the polarizing plate, and the polarizing plate does not slip relative to the substrate (the slippage approaches zero).
The following test of the slippage was performed for various samples of the surface protective film material for the polarizing plate, in which the sample was stretched for 1 hour using a tension of 30N, and the slippage of the surface protective film with respect to the surface of the substrate was measured. Then, a lighting inspection is performed on the panel including the various surface protective film materials, whether or not moire is generated is observed, and the results of the measurement of the slip amount and the lighting inspection are compared. The results are shown in table 2 below. Thereby, the anti-moire property of the surface protective film can be evaluated using the amount of slippage of the surface protective film with respect to the substrate as an index.
TABLE 2
From the test results in table 2, it was confirmed that when the slip of the surface protective film is greater than 2mm, the display has a brightness unevenness of 110 or more, that is, when the surface protective film is attached to the panel, the panel is likely to have moire, which causes brightness unevenness of the display. The better surface protection film has the slippage less than 1mm, does not generate the moire and has better anti-moire characteristic. It should be understood that although the example of table 2 uses a fixed tension of 30N for stretching and the slip of the surface protective film is greater than 2mm as an evaluation index for whether the moire is generated according to the measurement result, in other examples, the slip may be measured using a fixed tension of different magnitude. Therefore, in other embodiments of the method for evaluating a surface protective film according to the present disclosure, not only the slip amount of the surface protective film may be used as an evaluation index for determining whether the panel has the moire, but also a product of the magnitude of the fixed tension and the slip amount of the surface protective film, such as 60(N × mm) obtained by multiplying the fixed tension (30N) by the slip amount of the surface protective film (2 mm).
As described above, the present disclosure provides another method for evaluating a surface protection film, which includes a slip measurement step for obtaining a slip of the surface protection film relative to a substrate, and using the slip as an index for further evaluating anti-moire characteristics of various surface protection film samples. Therefore, the anti-moire evaluation method can be used for evaluating whether the surface protection film material for the polarizing plate is easy to generate the moire phenomenon of uneven brightness after the optical display device is manufactured.
In addition to using the stiffness attenuation and the slip as the index of the anti-moire property of the surface protection film, the surface protection film may be deformed and uneven thickness may be generated due to the increased tension of the surface protection film, so that the manufactured panel may easily generate moire, resulting in uneven brightness of the display. In order to solve the above problems, it is necessary to use a surface protective film having a small deformation rate when stretched under tension. Therefore, in some embodiments, a deformation rate measuring step may be further added to the method for evaluating a surface protective film, and the anti-moire characteristics of the surface protective film may be evaluated using the deformation rate of the surface protective film as an index. An example of the manner of measuring the deformation rate will be described in further detail below. It should be understood that the deformation rate measuring method disclosed in the present invention is not limited to the following parameters, and those skilled in the art can freely adjust the parameters used in the deformation rate measuring step.
The step of measuring the deformation rate of the surface protection film according to the present disclosure may be preceded by a sample pretreatment, and the surface protection film is cut into a rectangle with suitable dimensions, for example, in one embodiment, the dimensions of the surface protection film may be 15cm in length and 5cm in width, wherein the length direction is a Machine Direction (MD) for stretching the surface protection film.
Referring next to fig. 4A and 4B, fig. 4A and 4B are schematic diagrams illustrating a deformation rate measuring step of the surface protection film according to some embodiments. In some embodiments, a tensile tester (e.g., Shimadzu tensile AGX tester) is used to stretch the surface protective film sample, wherein the amount of stretch is set within the elastic region of the surface protective film material. Before stretching is performed as shown in fig. 4A, the original long side length L0 and the original short side length W0 of the surface protective film sample 402 may be measured, and the sample 402 may be fixed to a jig 404 of a tensile tester, wherein the fixing position of the jig 404 on the sample 402 is configured so that it can be stretched in the machine direction MD of the surface protective film sample 402.
Referring next to fig. 4B, the surface protective film sample 402 is stretched at a stretching speed to a fixed tension in the lengthwise direction thereof, and is maintained at the fixed tension for a stretching time. The lengths of the long side length L1 after the surface protective film was stretched and the short side length W1 after the stretching was measured after the above-mentioned stretching time to determine the amount of change in length L1-L0 and W0-W1 of the surface protective film after the stretching in the long side and the short side. It should be understood that the stretching speed, the fixed tension and the stretching time used in the deformation rate measuring step are not particularly limited in the embodiments of the present disclosure, and those skilled in the art can select suitable process parameters according to the material of the surface protection film as the sample, for example, the stretching speed may be 1 to 20mm/min and the fixed tension may be 130 to 180N. In some embodiments of the present disclosure, the stretching is performed using a speed of 5mm/min, and when the tension reaches 160N, the stretching is continued for 2 hours at a tension of 160N. In some other embodiments of the present disclosure, the stretching is performed using a speed of 5mm/min, and when the tension reaches 120N, the stretching is continued for 2 hours at a tension of 120N.
The deformation rate of the surface protective film was calculated by the following formula (3):
formula (3): the strain rate is ey/ex ((W0-W1)/W0)/((L1-L0)/L0)
Wherein ey is the change in the short side length W0-W1 divided by the original short side length W0 before stretching, and ex is the change in the long side length L1-L0 divided by the original long side length L0 before stretching.
The following test of the deformation rate was performed for various samples of the surface protective film material for the polarizing plate, in which the deformation rate was measured for various samples of the surface protective film using tensile forces of 120N and 160N, respectively. Then, a lighting inspection is performed on the panel including the various surface protective film materials, whether or not the moire is generated is observed, and the results of the deformation rate measurement and the lighting inspection are compared. The results are shown in table 3 below. Thereby, the anti-moire property of the surface protective film can be evaluated using the deformation rate of the surface protective film as an index.
TABLE 3
As can be seen from table 3, the surface protective film samples having a low deformation rate produced panels less likely to generate moire. From the test results in table 3, it was confirmed that when the tensile forces of 120N and 160N were used to measure the deformation rates, the panels produced from the surface protective film samples having deformation rates of 0.18 and 0.15 or less, respectively, had a luminance unevenness of 50 or less, had a normal (O) moire evaluation result, and had no problem of luminance unevenness; the panels manufactured with the surface protective film samples having deformation rates of 0.28 and 0.25 respectively had a brightness unevenness of 50 or more, and had a serious (X) or slight (Δ) moire evaluation result, and it was confirmed that light having a brightness unevenness penetrated through the panel, that is, the panel manufactured with the surface protective film sample having a high deformation rate was likely to generate moire. According to the moire evaluation results, it was revealed that the surface protective film sample deformation rate was less than 0.28 and moire was less likely to occur; the better surface protection film sample deformation rate is less than 0.18, no moire is generated, and the better anti-moire characteristic is achieved.
As described above, the present disclosure provides another method for evaluating a surface protective film, which includes a deformation rate measuring step to obtain a deformation rate of the surface protective film, and uses the deformation rate as an index for further evaluating anti-moire characteristics of various surface protective film samples. Therefore, the anti-moire evaluation method can be used for evaluating whether the surface protection film material for the polarizing plate is easy to generate the moire phenomenon of uneven brightness after the optical display device is manufactured.
It should be understood that one of ordinary skill in the art may use the stiffness attenuation rate measuring step, the slip amount measuring step, or the deformation rate measuring step provided in the present disclosure alone to evaluate the anti-moire property of the surface protective film, and may also use any combination of the stiffness attenuation rate measuring step, the slip amount measuring step, and the deformation rate measuring step to comprehensively evaluate the anti-moire property of the surface protective film. By simultaneously using a plurality of properties of the surface protective film, such as the rate of attenuation in stiffness, the amount of slip, and the deformation rate, as indices for evaluating the anti-moire characteristics of the surface protective film, the evaluation result of determining whether or not the surface protective film sample will generate moire can be made more accurate.
Although the present invention has been described with reference to the above preferred embodiments, it is not intended to be limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention. Therefore, the scope of the present invention is defined by the appended claims. Furthermore, each claim constitutes a separate embodiment, and combinations of various claims and embodiments are within the scope of the invention.
Claims (17)
1. A method for evaluating a surface protective film, comprising:
a stiffness attenuation ratio measuring step, comprising:
curling a surface protection film into a cylindrical sample, and fixing the cylindrical sample on a clamp, wherein the cylindrical sample has a first height;
pressing the cylindrical sample to a second height, stopping pressing, and measuring the change of the stiffness of the surface protection film along with time; and
calculating a stiffness attenuation ratio of the surface protective film from a change in stiffness of the surface protective film with time; and
the anti-moire property of the surface protective film was evaluated by using the stiffness attenuation ratio of the surface protective film as an index.
2. The method for evaluating a surface protective film according to claim 1, wherein a material of the surface protective film comprises a cellulose-based resin, an acrylic-based resin, a non-crystalline polyolefin-based resin, a polyester-based resin, a polycarbonate-based resin, or any combination thereof.
3. The method for evaluating a surface protective film according to claim 1, wherein the first height is 50 to 90mm, and the second height is 5 to 60 mm.
4. The method for evaluating a surface protective film according to claim 1, wherein the stiffness decay rate is (maximum stiffness-post-reaction stiffness)/maximum stiffness, maximum stiffness is the instantaneous stiffness at which the cylindrical sample reaches the second level, and post-reaction stiffness is the stiffness taken after a measurement time after the maximum stiffness is produced.
5. The method for evaluating a surface protective film according to claim 4, wherein the measurement time of the rate of attenuation of stiffness is 1 to 5 seconds; and/or further wherein the stiffness decay rate is less than 4.7%.
6. The method for evaluating a surface protective film according to claim 1, wherein the surface protective film is attached to a soft material before the surface protective film is rolled.
7. The method of evaluating a surface protective film according to claim 1, further comprising:
a slippage measurement step, comprising:
attaching the surface protection film to the surface of a substrate;
fixing the surface protection film on a tensile testing machine; and
stretching the substrate for a stretching time at a fixed tension, and measuring the slippage of the surface protection film relative to the substrate; and
evaluating the anti-moire property of the surface protection film by using the slippage of the surface protection film relative to the substrate as an index.
8. The method of claim 7, further comprising evaluating the anti-moire property of the surface protection film by multiplying the slip by the constant tension.
9. The method for evaluating a surface protective film according to claim 7, further characterized in that the slip amount is less than 1mm as an index.
10. The method for evaluating a surface protective film according to claim 7, wherein the fixing tension is 10 to 60N; and/or wherein the stretching time is 0.5 to 3 hours.
11. The method of evaluating a surface protective film according to claim 1, further comprising:
a deformation rate measuring step, comprising:
cutting the surface protection film into a rectangle, and measuring the lengths of the long side and the short side of the surface protection film;
stretching the surface protection film to a fixed tension at a stretching speed in the long side direction of the rectangle, and maintaining the fixed tension for a stretching time;
measuring the lengths of the long side and the short side of the stretched surface protection film; and
calculating the deformation rate of the surface protection film according to the lengths of the long side and the short side of the stretched surface protection film; and
the anti-moire property of the surface protective film was evaluated using the deformation rate of the surface protective film as an index.
12. The method for evaluating a surface protective film according to claim 11, wherein the deformation rate of the surface protective film is ey/ex, ey is the amount of change in the length of the short side/the length of the short side before stretching, and ex is the amount of change in the length of the long side/the length of the long side before stretching.
13. The method for evaluating a surface protective film according to claim 12, further characterized in that a deformation rate of the surface protective film is less than 0.28 as an index.
14. The method for evaluating a surface protective film according to claim 11, wherein the stretching speed is 1 to 20 mm/min; and/or wherein the fixed tension is 130-180N.
15. The method of evaluating a surface protective film according to any one of claims 1 to 14, further comprising:
a moire evaluation step of evaluating whether or not a moire is generated in a panel made of the surface protective film, comprising:
adhering the surface protective film to a polarizing film to prepare a polarizing plate;
attaching the polarizing plate to a display panel, wherein the display panel comprises a backlight module for emitting a light source;
using the light source to perform lighting inspection; and
capturing an image of the light source penetrating through the polarizing plate by using a camera;
confirming a position with uneven chroma and a position with even chroma in the image; and
and comparing the RGB color codes of the position with the uniform chromaticity.
16. The method of evaluating a surface protective film according to claim 15, wherein comparing the RGB color codes of the chromaticity unevenness position and the chromaticity uniformity position further comprises:
obtaining a luminance uneven position color code R1, G1, B1 of the chrominance uneven position and a luminance even position color code R2, G2, B2 of the luminance even position; and
the luminance unevenness is calculated using a formula of √ root ((R1-R2)2+(G1－G2)2+(B1－B2)2)。
17. The method of evaluating a surface protective film according to claim 16, wherein a luminance unevenness of less than 50 is evaluated as normal;
the brightness unevenness is evaluated to be slight between 50 and 110; and
the luminance unevenness larger than 110 was evaluated as serious.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410173476.9A CN118130291A (en) | 2021-01-21 | 2021-07-01 | Evaluation method of surface protection film |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| TW110102218A TWI757061B (en) | 2021-01-21 | 2021-01-21 | Method of evaluation for surface protective film |
| TW110102218 | 2021-01-21 |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410173476.9A Division CN118130291A (en) | 2021-01-21 | 2021-07-01 | Evaluation method of surface protection film |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113567283A true CN113567283A (en) | 2021-10-29 |
| CN113567283B CN113567283B (en) | 2024-06-14 |
Family
ID=78163385
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410173476.9A Pending CN118130291A (en) | 2021-01-21 | 2021-07-01 | Evaluation method of surface protection film |
| CN202110744408.XA Active CN113567283B (en) | 2021-01-21 | 2021-07-01 | Evaluation method of surface protection film |
Family Applications Before (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410173476.9A Pending CN118130291A (en) | 2021-01-21 | 2021-07-01 | Evaluation method of surface protection film |
Country Status (2)
| Country | Link |
|---|---|
| CN (2) | CN118130291A (en) |
| TW (1) | TWI757061B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114460672A (en) * | 2022-01-19 | 2022-05-10 | 住华科技股份有限公司 | Method for evaluating surface protective film, method for manufacturing optical film structure, and method for manufacturing display |
| CN114460672B (en) * | 2022-01-19 | 2024-07-09 | 住华科技股份有限公司 | Evaluation method for surface protective film, manufacturing method for optical film structure, and manufacturing method for display |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TW201447402A (en) * | 2013-04-16 | 2014-12-16 | Fujifilm Corp | Polarizer, manufacturing method thereof, and image display device |
| CN106054302A (en) * | 2015-04-10 | 2016-10-26 | 柯尼卡美能达株式会社 | Polaroid protection film, polaroid therewith, and manufacturing method for polaroid protection film |
| TW201706637A (en) * | 2015-06-19 | 2017-02-16 | Sumitomo Chemical Co | Production method for polarizing plate with protective film |
| JP2018187785A (en) * | 2017-04-28 | 2018-11-29 | 株式会社クラレ | Production method of multilayer film |
| CN111308604A (en) * | 2015-11-13 | 2020-06-19 | 住友化学株式会社 | Polarizing plate, liquid crystal display device, and organic electroluminescent display device |
| TW202033376A (en) * | 2018-12-05 | 2020-09-16 | 日商阪東化學股份有限公司 | Surface protection film for flexible display |
| CN111829904A (en) * | 2019-04-22 | 2020-10-27 | 住友化学株式会社 | Inspection method, method for manufacturing resin film roll, and resin film roll |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5963453B2 (en) * | 2011-03-15 | 2016-08-03 | 株式会社荏原製作所 | Inspection device |
-
2021
- 2021-01-21 TW TW110102218A patent/TWI757061B/en active
- 2021-07-01 CN CN202410173476.9A patent/CN118130291A/en active Pending
- 2021-07-01 CN CN202110744408.XA patent/CN113567283B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TW201447402A (en) * | 2013-04-16 | 2014-12-16 | Fujifilm Corp | Polarizer, manufacturing method thereof, and image display device |
| CN106054302A (en) * | 2015-04-10 | 2016-10-26 | 柯尼卡美能达株式会社 | Polaroid protection film, polaroid therewith, and manufacturing method for polaroid protection film |
| TW201706637A (en) * | 2015-06-19 | 2017-02-16 | Sumitomo Chemical Co | Production method for polarizing plate with protective film |
| CN111308604A (en) * | 2015-11-13 | 2020-06-19 | 住友化学株式会社 | Polarizing plate, liquid crystal display device, and organic electroluminescent display device |
| JP2018187785A (en) * | 2017-04-28 | 2018-11-29 | 株式会社クラレ | Production method of multilayer film |
| TW202033376A (en) * | 2018-12-05 | 2020-09-16 | 日商阪東化學股份有限公司 | Surface protection film for flexible display |
| CN111829904A (en) * | 2019-04-22 | 2020-10-27 | 住友化学株式会社 | Inspection method, method for manufacturing resin film roll, and resin film roll |
Non-Patent Citations (2)
| Title |
|---|
| 刘成霞;罗秋霞;施美琴;: "织物多方向硬挺度测试方法研究", 现代纺织技术, no. 02 * |
| 沈建刚: "保护膜的基本特征简介", 中国建材科技, no. 04 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114460672A (en) * | 2022-01-19 | 2022-05-10 | 住华科技股份有限公司 | Method for evaluating surface protective film, method for manufacturing optical film structure, and method for manufacturing display |
| TWI795175B (en) * | 2022-01-19 | 2023-03-01 | 住華科技股份有限公司 | Method of evaluating surface protective film, method of manufacturing optical film structure, and method of manufacturing display device |
| CN114460672B (en) * | 2022-01-19 | 2024-07-09 | 住华科技股份有限公司 | Evaluation method for surface protective film, manufacturing method for optical film structure, and manufacturing method for display |
Also Published As
| Publication number | Publication date |
|---|---|
| TW202229832A (en) | 2022-08-01 |
| CN113567283B (en) | 2024-06-14 |
| CN118130291A (en) | 2024-06-04 |
| TWI757061B (en) | 2022-03-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP6850601B2 (en) | Image display device | |
| KR102347401B1 (en) | Polarizer, polarizer plate with adhesive, and image display device | |
| TWI507298B (en) | Heat activated optically clear adhesive for bonding display panels | |
| CN110346861B (en) | Optical laminate and image display device | |
| CN105467492B (en) | Polarizing plate | |
| TW201007229A (en) | Adhesive polarization plate, image display device and methods for manufacturing adhesive polarization plate and image display device | |
| WO2016052732A1 (en) | Optical film layered body, optical display device using optical film layered body, and transparent protective film | |
| TW202030088A (en) | Optical laminate and image display device provided with same | |
| KR20160034219A (en) | Polarizing plate | |
| JP2017040907A (en) | Convex surface side polarizing plate for curved image display panel | |
| CN115023635A (en) | Method for manufacturing optical laminate and display device | |
| CN113567283B (en) | Evaluation method of surface protection film | |
| CN108121027B (en) | Method for producing polarizing laminated film with protective film and method for producing polarizing plate | |
| JP2016212443A (en) | Optical film laminate and method for manufacturing the same | |
| KR102392232B1 (en) | Polarizing plate for curved image display panel | |
| WO2021085000A1 (en) | Optical laminate and display device | |
| KR102593816B1 (en) | Optical laminate and image display device using the optical laminate | |
| JP2018013773A (en) | Optical member and liquid crystal display | |
| TWI805043B (en) | Method of evaluation for surface protective film | |
| WO2021131237A1 (en) | Image display device and set of optical members | |
| TW202229942A (en) | Polarizing plate, cover glass-equipped polarizing plate, and image display device | |
| JP7261336B1 (en) | Polarizer | |
| CN113755121B (en) | Optical adhesive, optical adhesive layer and forming method thereof, and optical laminate | |
| WO2020100468A1 (en) | Optical laminate and image display device provided with same | |
| JP2022140346A (en) | Polarizing plate and method for manufacturing the same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |