Dye-based high-durability oled polarizing sheet for vehicle display and method for preparing the same

Abstract

The application relates to the technical field of polarizing plates and discloses a preparation method of a dye-based high-durability OLED polarizing plate for vehicle-mounted display, which comprises the following steps: pretreating a PVA film by swelling in a swelling tank containing 1.0wt%-2.5wt% boric acid; dyeing, soaking the PVA film after dyeing treatment in a solution tank containing boric acid, and stretching the PVA film; the concentration of boric acid is 1wt%-6wt%, drying, curing the original plate, gluing, coating pressure-sensitive adhesive on the dye-based polarizing original plate, and then compounding compensation film A, compensation film B and the like. The dye-based high-durability OLED polarizing plate prepared by the application has a thin structure, excellent weather resistance, can meet 105 DEG C*1000h dry temperature test and 85 DEG C*85%RH*1000h high-temperature and high-humidity test, and after weather resistance test, the change rate of the optical performance of the polarizing plate is less than or equal to 5%, and the product is free of depolarization and delamination.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of polarizing sheet, in particular to a dye-based high-durability OLED polarizing sheet for vehicle display and a preparation method thereof. BACKGROUND

[0002] OLED (Organic Light Emitting Diode) is a kind of organic light emitting diode with self-luminous characteristics. Due to its ultra-thin, flexible, high contrast and fast response characteristics, it is widely used in display, lighting and other electronic devices. In the field of display technology, polarizing sheet is an important optical component for controlling the direction and polarization state of light. At present, OLED display technology has begun to be applied in vehicle display, becoming a new research and application direction. In order to realize breakthrough in high-end vehicle display field, higher requirements are needed for the softness, thinness and weather resistance of the polarizing sheet.

[0003] Although the market has launched an iodine-based thin OLED polarizing sheet with a thickness of 190 μm, a weather resistance of 65℃*93%RH*500h and 95℃*240h, and some have begun to be applied to vehicle display. However, compared with the increasingly stringent weather resistance design of vehicle display, the traditional preparation process of this iodine-based product restricts its application and promotion in this field to some extent, and it is difficult to meet the weather resistance requirements of high-end vehicle display field. The stringent use requirements of vehicle display technology make the material selection and preparation process of polarizing sheet more complex. The traditional iodine-based polarizing sheet material cannot meet the weather resistance requirements of high temperature 105℃*1000h and high temperature and high humidity 85℃*85%RH*1000h, so a new polarizing sheet product structure design needs to be constructed to realize the application of OLED polarizing sheet in high-end vehicle display field. SUMMARY

[0004] The present application aims to provide a dye-based high-durability OLED polarizing sheet structure for vehicle display and a preparation method thereof, which meets the requirements of dry temperature 105℃*1000h and high temperature and high humidity 85℃*85%RH*1000h weather resistance test, and at least provides a beneficial choice or creates conditions to solve one or more technical problems in the prior art.

[0005] To achieve the above purpose, the technical scheme adopted by the present application is as follows.

[0006] A preparation method of a dye-based high-durability OLED polarizing sheet for vehicle display, the preparation steps of which are as follows: 1) pretreatment, soaking the PVA film in a first water washing tank for water washing, and then entering a swelling tank containing 1.0wt%-2.5%wt boric acid for swelling pretreatment; 2) dyeing, soaking the PVA film treated by swelling in a dyeing solution tank containing dichroic dye for dyeing treatment; the dyeing solution contains 0.003wt%-5wt% dichroic dye and 0.5wt%-2.5wt% dyeing auxiliary; 3) stretching, soaking the PVA film treated by dyeing in a solution tank containing boric acid for stretching treatment; the concentration of boric acid is 1wt%-6wt%, the tank solution temperature is 25°C-65°C, and the stretching multiple of the PVA film is 3-7 times; 4) drying, washing and drying the PVA film treated by stretching to obtain a dye-based polarizing element; the drying temperature is 30°C-80°C; 5) original plate curing, coating the dye-based polarizing element treated by drying with an adhesive on both sides, respectively bonding a cellulose triacetate film, then drying and curing the adhesive to form a thin dye-based polarizing film; the drying temperature is 90°C-130°C; 6) gluing, coating the dye-based polarizing original plate with pressure-sensitive adhesive, then bonding compensation film A; coating the side of the compensation film A without pressure-sensitive adhesive with pressure-sensitive adhesive, then bonding compensation film B; coating the side of the compensation film B without pressure-sensitive adhesive with pressure-sensitive adhesive, and then bonding a layer of release film.

[0007] More preferably, in step 1), the PVA film is a PVA film with a thickness of 20-40μm.

[0008] More preferably, in step 5), the cellulose triacetate film is a cellulose triacetate film layer with ultraviolet resistance, and the ultraviolet resistance refers to that the transmittance of the full spectrum at 380nm is 0-5%.

[0009] More preferably, in step 5), the thickness of the cellulose triacetate film is 40μm-60μm.

[0010] More preferably, in step 5), the thickness of the thin dye-based polarizing film formed is 100-130μm.

[0011] More preferably, in step 5), the transmittance of the thin dye-based polarizing film formed is 39%-42%, the degree of polarization is ≥98%, and the hue bs value is ±5.

[0012] More preferably, in step 6), the compensation film A is an A-plate type liquid crystal compensation film, the thickness of the compensation film A is 1-5μm, the compensation value Re is 250nm-290nm, and the optical axis angle requirement is 60-90°.

[0013] More preferably, in step 6), the compensation film B is an A-plate type liquid crystal compensation film, the thickness of the compensation film B is 1-5 μm, the compensation value Re is 120 nm-160 nm, and the optical axis angle is 5-25°.

[0014] In another aspect, the application also provides a dye-based high-durability OLED polarizing sheet for vehicle display prepared by the preparation method of the dye-based high-durability OLED polarizing sheet for vehicle display, wherein the optical performance requirements of the polarizing sheet are as follows: transmittance: 39%-42%, preferably 40%; degree of polarization: ≥98%, preferably 99%; reflectance: ≤4%; and the thickness of the polarizing sheet is 130 μm-270 μm.

[0015] The application has at least the following beneficial effects.

[0016] Firstly, the contradiction between the polarization effect and the light transmittance needs to be balanced. Reducing the thickness of the polarizing sheet may reduce the polarization effect of light, resulting in a decrease in the contrast ratio of the display. Therefore, while maintaining the reduced thickness of the dye-based polarizing sheet, the balance between the polarization effect and the light transmittance needs to be ensured by optimizing the material combination and the preparation process. The dye-based high-durability OLED polarizing sheet prepared by the application has high degree of polarization and good overall display visual effect, with a transmittance of 39%-42%, a degree of polarization of ≥98%, and a reflectance of ≤4%. The brightness and contrast ratio of the display are effectively improved, the reflection and scattering phenomena are reduced, the overall visual black state effect is achieved, and the quality of the displayed image is better improved.

[0017] Secondly, the dye-based high-durability OLED polarizing sheet prepared by the application has excellent weather resistance, meeting the dry temperature test of 105℃*1000h and the wet temperature test of 85℃*85%RH*1000h. After the weather resistance test, the optical performance change rate of the polarizing sheet is ≤5%, and the product has no depolarization and delamination.

[0018] Thirdly, the thickness of the dye-based high-durability OLED polarizing sheet prepared by the application is 130 μm-270 μm, meeting the technical requirements for high-end vehicle display.

[0019] Fourthly, the dye-based high-durability OLED polarizing sheet also faces challenges in the preparation process, which requires high-precision technology and equipment to ensure the preparation of uniform and stable thin film structures. The instability of the preparation process may lead to unstable quality of the polarizing sheet, affecting the performance and service life of the display. The dye-based high-durability OLED polarizing sheet of the application adopts a new structural design and manufacturing process, which can reduce the manufacturing cost. Compared with the traditional polarizing sheet manufacturing method, the polarizing sheet manufacturing process of the application is simpler and more efficient, which can improve the production efficiency and reduce the manufacturing cost.BRIEF DESCRIPTION OF DRAWINGS BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The polarizing plate structure in the embodiment of the application is shown. DETAILED DESCRIPTION

[0021] To facilitate those skilled in the art to better understand the essence of the present application, the specific embodiments of the present application are described in detail below.

[0022] The present application provides a kind of dye-based high durability OLED polarizing plate preparation method for vehicle display, mainly solves the following technical problems: 1) realize the thin type of dye-based OLED polarizing plate: iodine-based OLED polarizing plate is not conducive to the application in high-end vehicle display due to its thickness and weatherability performance is insufficient.The present application provides a kind of dye-based high durability OLED polarizing plate solution, which can reduce the thickness of OLED polarizing plate while improving weatherability.2) improve the performance stability of OLED polarizing plate: there may be performance attenuation and short service life in the long-term use of OLED polarizing plate.The present application improves the performance stability of OLED polarizing plate by optimizing material selection and preparation process, prolongs the service life.

[0023] REFERENCE Figure 1 As shown, the dye-based high durability OLED polarizing plate in the present application has a double compensation function, and is composed of a polarizing plate original plate, a compensation film layer A and a compensation film layer B from top to bottom.The polarizing plate original plate is composed of a dye-based polarizing film and protective films (cellulose triacetate films) compounded on the upper and lower sides of the dye-based polarizing film, and the polarizing plate original plate and the compensation film layer A, and the compensation film layer A and the compensation film layer B are respectively bonded by corresponding pressure-sensitive adhesive.

[0024] Among them, the protective film adopts cellulose triacetate film layer with ultraviolet resistance, and the ultraviolet resistance refers to the transmittance of full light spectrum at 380 nm is 0-5%, at the same time, the thickness of cellulose triacetate film is 40 μm-60 μm, preferably 40 μm.

[0025] The dye-based polarizing film refers to a 30 μm polyvinyl alcohol film after swelling, dyeing, stretching, complementary color, drying, and the dyeing liquid is dichroic dye liquid.Thin dye-based polarizing film is bonded with two layers of cellulose triacetate film on the upper and lower sides by adhesive to form a thin dye-based polarizing original plate, which has the characteristics of high temperature resistance and non-yellowing, and the thickness requirement is 100-200 μm, preferably 110 μm.

[0026] The dichroic dye liquid above is one or more of basic dye, acid dye, direct dye and reactive dye, and the hue bs value of the dye-based polarizing original plate is ± 5.

[0027] The pressure-sensitive adhesive is mainly used for the bonding of thin dye-based polarizing films and compensation films (including compensation film A and compensation film B), and the thickness is required to be 10-20 μm, preferably 15 μm.

[0028] The compensation film A is an A-plate type liquid crystal compensation film. The main function is to realize the effect of overall visual black state of the polarizing sheet. The thickness of the compensation film is required to be 1-5 μm, preferably 2-3 μm. The compensation value Re is required to be 250 nm-290 nm, preferably 260-280 nm. The optical axis angle is required to be 60-90°, preferably 65-85°.

[0029] The compensation film B is an A-plate type liquid crystal compensation film. The main function is to realize the effect of integrated black of the polarizing sheet. The thickness of the compensation film is required to be 1-5 μm, preferably 2-3 μm. The compensation value Re is required to be 120 nm-160 nm, preferably 133-143 nm. The optical axis angle is required to be 5-25°, preferably 10-20°.

[0030] Example 1.

[0031] A dye-based high-durability OLED polarizing sheet for vehicle display is prepared by the following steps.

[0032] 1) Pretreatment: a 30 μm thick polyvinyl alcohol (PVA) film is immersed in a first water washing tank for water washing, and then enters a swelling tank containing 1.5%wt boric acid for swelling pretreatment.

[0033] 2) Dyeing: the PVA film after swelling treatment is immersed in a dyeing solution tank containing dichroic dyes for dyeing treatment; the dyeing solution contains 0.06 wt% concentration of dichroic dyes, 1.5 wt% concentration of dyeing auxiliaries, etc., and the dichroic dyes can be single dye or a mixture of multiple dyes.

[0034] 3) Stretching: the PVA film after dyeing treatment is immersed in a solution tank containing boric acid for stretching treatment; the concentration of boric acid is 2.5 wt%, the tank solution temperature is 55°C, and the stretching multiple of the PVA film is 5 times.

[0035] 4) Drying: the PVA film after stretching treatment is washed and dried to obtain a dye-based polarizing element; the drying temperature is 60°C.

[0036] 5) Original plate curing: the dye-based polarizing element after drying is coated with an adhesive on both sides, and is bonded with triacetate cellulose films, respectively, and then is subjected to drying and curing of the adhesive to form a thin dye-based polarizing film.

[0037] The cellulose triacetate film is provided with a cellulose triacetate film layer with anti-ultraviolet property, the total light transmittance at 380 nm is 0.5%, and the thickness of the cellulose triacetate film is 40 μm.

[0038] The adhesive is a polyvinyl alcohol adhesive which does not yellow at high temperature (105 DEG C); the prepared thin dye-based polarizing film has a transmittance of 39%, a degree of polarization of 98%, and a hue b of -3; and the drying temperature is 125 DEG C.

[0039] 6) gluing, coating the dye-based polarizing original plate with pressure-sensitive adhesive, then compounding compensation film A; coating the side of compensation film A which is not coated with pressure-sensitive adhesive with pressure-sensitive adhesive, then compounding compensation film B; coating the side of compensation film B which is not coated with pressure-sensitive adhesive with pressure-sensitive adhesive, then compounding a layer of release film; obtaining a dye-based high-durability OLED polarizing sheet.

[0040] The compensation film A is an A-plate type liquid crystal compensation film with a thickness of 2 μm and a compensation value Re of 260 nm; the optical axis angle is 85 DEG. The compensation film B is an A-plate type liquid crystal compensation film with a thickness of 3 μm and a compensation value Re of 143 nm; the optical axis angle is 20 DEG. The thickness of the single layer of pressure-sensitive adhesive is 20 μm.

[0041] Example 2.

[0042] A dye-based high-durability OLED polarizing sheet for vehicle display is prepared by the following steps.

[0043] 1) pretreatment, using a 30 μm polyvinyl alcohol (PVA) film, soaking it in a first water washing tank for water washing, and then entering a swelling tank containing 2.0 wt% boric acid for swelling pretreatment.

[0044] 2) dyeing, soaking the PVA film after swelling treatment in a dyeing solution tank containing dichromatic dye for dyeing treatment; the dyeing solution contains 0.50 wt% dichromatic dye and 1.5 wt% dyeing auxiliary; the dichromatic dye can be a single dye or a mixture of multiple dyes.

[0045] 3) stretching, soaking the PVA film after dyeing treatment in a solution tank containing boric acid for stretching treatment; the boric acid concentration is 1.5 wt%, the tank solution temperature is 50 DEG C, and the stretching multiple of the PVA film is 3 times.

[0046] 4) drying, washing and drying the PVA film after stretching treatment to obtain a dye-based polarizing element; the drying temperature is 60 DEG C.

[0047] 5) curing the original plate, the dye-based polarizing element after drying coated on both sides of the adhesive, respectively, with a triacetate cellulose film, then, drying, curing the adhesive, forming a thin dye-based polarizing film; the adhesive is a polyvinyl alcohol adhesive that does not yellow at high temperatures (105°C).

[0048] The triacetate cellulose film uses a triacetate cellulose film layer with UV resistance, and the full-spectrum transmittance at 380 nm is 3%. The thickness of the triacetate cellulose film is 60 μm.

[0049] The transmittance of the prepared thin dye-based polarizing film is 39%, the degree of polarization is 98%, and the hue b is -4; the drying temperature is 125°C.

[0050] 6) gluing, coating the dye-based polarizing original plate with pressure-sensitive adhesive, then compounding compensation film A; on the side of compensation film A that is not coated with pressure-sensitive adhesive, coating pressure-sensitive adhesive, then compounding compensation film B; on the side of compensation film B that is not coated with pressure-sensitive adhesive, coating pressure-sensitive adhesive, then compounding a layer of release film; obtaining a dye-based high-durability OLED polarizing sheet.

[0051] The compensation film A is an A-plate type liquid crystal compensation film with a thickness of 3 μm and a compensation value Re of 280 nm. The optical axis angle is 65°. The compensation film B is an A-plate type liquid crystal compensation film with a thickness of 2 μm and a compensation value Re of 133 nm. The optical axis angle is 10°. The thickness of the single layer of pressure-sensitive adhesive is 15 μm.

[0052] Example 3.

[0053] A dye-based high-durability OLED polarizing sheet for vehicle display is prepared by the following steps.

[0054] 1) pretreatment, using a 30 μm polyvinyl alcohol (PVA) film, soaking it in the first water washing tank for water washing, and then entering the swelling tank containing 1.8 wt% boric acid for swelling pretreatment.

[0055] 2) dyeing, soaking the PVA film treated by swelling in a dyeing solution tank containing dichromatic dye for dyeing treatment; the dyeing solution contains 1.5 wt% dichromatic dye, 0.8 wt% dyeing auxiliary, etc., and the dichromatic dye can be a single dye or a mixture of multiple dyes.

[0056] 3) stretching, soaking the PVA film treated by dyeing in a solution tank containing boric acid for stretching treatment; the concentration of boric acid is 5.5 wt%, the tank solution temperature is 65°C, and the stretching multiple of the PVA film is 7 times.

[0057] 4) drying, washing and drying the PVA film after stretching treatment to obtain a dye-based polarizing element; the drying temperature is 60°C.

[0058] 5) primary plate curing, coating the dye-based polarizing element after drying with an adhesive on both sides, respectively, adhering a triacetate cellulose film, then drying and curing the adhesive to form a thin dye-based polarizing film; the adhesive is a polyvinyl alcohol adhesive that does not yellow at high temperature (105°C). The triacetate cellulose film is a triacetate cellulose film layer with ultraviolet resistance, the transmittance of the full spectrum at 380 nm is 1%, and the thickness of the triacetate cellulose film is 50μm. The transmittance of the thin dye-based polarizing film obtained is 39%, the degree of polarization is 98%, and the hue b is -4; the drying temperature is 110°C.

[0059] 6) gluing, coating the dye-based polarizing primary plate with pressure-sensitive adhesive, then compounding compensation film A; coating the side of compensation film A that is not coated with pressure-sensitive adhesive with pressure-sensitive adhesive, then compounding compensation film B; coating the side of compensation film B that is not coated with pressure-sensitive adhesive with pressure-sensitive adhesive, then compounding a layer of release film; obtaining a dye-based high-durability OLED polarizing sheet.

[0060] The compensation film A is an A-plate type liquid crystal compensation film with a thickness of 5μm and a compensation value Re of 290nm. The optical axis angle is 90°. The compensation film B is an A-plate type liquid crystal compensation film with a thickness of 5μm, a compensation value Re of 120nm, and an optical axis angle of 25°. The thickness of the single layer of pressure-sensitive adhesive is 10μm.

[0061] Example 4.

[0062] A dye-based high-durability OLED polarizing sheet for vehicle display is prepared by the following steps.

[0063] 1) pretreatment, a 30μm polyvinyl alcohol (PVA) film is immersed in a first water washing tank for water washing, and then enters a swelling tank containing 2.5wt% boric acid for swelling pretreatment.

[0064] 2) dyeing, the PVA film after swelling treatment is immersed in a dyeing solution tank containing dichromatic dye for dyeing treatment; the dyeing solution mainly includes 1.5wt% dichromatic dye and 2.0wt% dyeing auxiliary, etc., and the dichromatic dye can be a single dye or a mixture of multiple dyes.

[0065] 3) stretching, the PVA film after dyeing treatment is immersed in a solution tank containing boric acid for stretching treatment; the concentration of boric acid is 3.5wt%, the tank temperature is 60°C, and the stretching multiple of the PVA film is 6 times.

[0066] 4) drying, washing and drying the PVA film after stretching treatment to obtain a dye-based polarizing element; the drying temperature is 80°C.

[0067] 5) primary plate curing, coating the dye-based polarizing element after drying with an adhesive on both sides, respectively, adhering a triacetate cellulose film, then drying and curing the adhesive to form a thin dye-based polarizing film; the adhesive is a polyvinyl alcohol adhesive that does not yellow at high temperature (105°C). The triacetate cellulose film is a triacetate cellulose film layer with ultraviolet resistance, the transmittance of the full spectrum at 380 nm is 2%, and the thickness of the triacetate cellulose film is 40μm.

[0068] The transmittance of the prepared thin dye-based polarizing film is 42%, the degree of polarization is 99%, and the hue b is 5; the drying temperature is 110°C.

[0069] 6) gluing, coating the dye-based polarizing primary plate with pressure-sensitive adhesive, then compounding compensation film A; coating the side of compensation film A that is not coated with pressure-sensitive adhesive with pressure-sensitive adhesive, then compounding compensation film B; coating the side of compensation film B that is not coated with pressure-sensitive adhesive with pressure-sensitive adhesive, then compounding a layer of release film; obtaining a dye-based high-durability OLED polarizing sheet.

[0070] The compensation film A is an A-plate type liquid crystal compensation film with a thickness of 1μm and a compensation value Re of 250nm. The optical axis angle is 60°. The compensation film B is an A-plate type liquid crystal compensation film with a thickness of 1μm and a compensation value Re of 160nm, and the optical axis angle is 5°. The thickness of the single layer of pressure-sensitive adhesive is 15μm.

[0071] Example 5.

[0072] A dye-based high-durability OLED polarizing sheet for vehicle display is prepared by the following steps.

[0073] 1) pretreatment, a 30μm polyvinyl alcohol (PVA) film is soaked in a first water washing tank for water washing, and then enters a swelling tank containing 2.0wt% boric acid for swelling pretreatment.

[0074] 2) dyeing, the PVA film after swelling treatment is soaked in a dyeing solution tank containing dichromatic dye for dyeing treatment; the dyeing solution mainly includes 3.5wt% dichromatic dye and 2.5wt% dyeing auxiliary, etc., and the dichromatic dye can be a single dye or a mixture of multiple dyes.

[0075] 3) stretching, the PVA film after dyeing treatment is soaked in a solution tank containing boric acid for stretching treatment; the concentration of boric acid is 3.5wt%, the tank solution temperature is 60°C, and the stretching multiple of the PVA film is 5 times.

[0076] 4) drying, washing and drying the PVA film after stretching treatment to obtain a dye-based polarizing element; the drying temperature is 80°C.

[0077] 5) primary plate curing, coating the dye-based polarizing element after drying with an adhesive on both sides, respectively, and then adhering a triacetate cellulose film to form a thin dye-based polarizing film; the adhesive is a polyvinyl alcohol adhesive that does not yellow at high temperature (105°C). The triacetate cellulose film is a triacetate cellulose film layer with ultraviolet resistance, and the transmittance of the full spectrum at 380 nm is 2%, and the thickness of the triacetate cellulose film is 40 μm.

[0078] The transmittance of the prepared thin dye-based polarizing film is 42.5%, the degree of polarization is 99.2%, and the hue b is 5; the drying temperature is 95°C.

[0079] 6) gluing, coating the dye-based polarizing primary plate with pressure-sensitive adhesive, and then compounding compensation film A; coating the side of compensation film A without pressure-sensitive adhesive with pressure-sensitive adhesive, and then compounding compensation film B; coating the side of compensation film B without pressure-sensitive adhesive with pressure-sensitive adhesive, and then compounding a layer of release film; obtaining a dye-based high-durability OLED polarizing sheet. The compensation film A is an A-plate type liquid crystal compensation film with a thickness of 1 μm and a compensation value Re of 250 nm. The optical axis angle is 60°. The compensation film B is an A-plate type liquid crystal compensation film with a thickness of 1 μm and a compensation value Re of 160 nm. The optical axis angle is 5°. The thickness of the single layer of pressure-sensitive adhesive is 20 μm.

[0080] Example 6.

[0081] A dye-based high-durability OLED polarizing sheet for vehicle display is prepared by the following steps.

[0082] 1) pretreatment, using a 30 μm polyvinyl alcohol (PVA) film, soaking it in a first water washing tank for water washing, and then entering a swelling tank containing 2.0 wt% boric acid for swelling pretreatment.

[0083] 2) dyeing, soaking the PVA film after swelling treatment in a dyeing solution tank containing dichromatic dye for dyeing treatment; the dyeing solution mainly includes 3.5 wt% dichromatic dye and 2.5 wt% dyeing auxiliary, and the dichromatic dye can be a single dye or a mixture of multiple dyes.

[0084] 3) stretching, soaking the PVA film after dyeing treatment in a solution tank containing boric acid for stretching treatment; the boric acid concentration is 3.5 wt%, the tank solution temperature is 60°C, and the stretching multiple of the PVA film is 5.5 times.

[0085] 4) drying, washing and drying the PVA film after stretching treatment to obtain a dye-based polarizing element; the drying temperature is 80°C.

[0086] 5) primary plate curing, coating the dye-based polarizing element after drying with an adhesive on both sides, respectively, and then adhering a triacetate cellulose film to form a thin dye-based polarizing film; the adhesive is a polyvinyl alcohol adhesive that does not yellow at high temperature (105°C). The triacetate cellulose film is a triacetate cellulose film layer with ultraviolet resistance, and the transmittance of the full spectrum at 380 nm is 2%, and the thickness of the triacetate cellulose film is 40 μm.

[0087] The transmittance of the prepared thin dye-based polarizing film is 42.5%, the degree of polarization is 99.2%, and the hue b is 5; the drying temperature is 105°C.

[0088] 6) gluing, coating the dye-based polarizing primary plate with pressure-sensitive adhesive, and then compounding compensation film A; coating the side of compensation film A without pressure-sensitive adhesive with pressure-sensitive adhesive, and then compounding compensation film B; coating the side of compensation film B without pressure-sensitive adhesive with pressure-sensitive adhesive, and then compounding a layer of release film; obtaining a dye-based high-durability OLED polarizing sheet. The compensation film A is an A-plate type liquid crystal compensation film with a thickness of 1 μm and a compensation value Re of 250 nm. The optical axis angle is 60°. The compensation film B is an A-plate type liquid crystal compensation film with a thickness of 1 μm and a compensation value Re of 160 nm. The optical axis angle is 5°. The thickness of the single layer of pressure-sensitive adhesive is 20 μm.

[0089] Example 7.

[0090] A dye-based high-durability OLED polarizing sheet for vehicle display is prepared by the following steps.

[0091] 1) pretreatment, using a 30 μm polyvinyl alcohol (PVA) film, soaking it in a first water washing tank for water washing, and then entering a swelling tank containing 2.0 wt% boric acid for swelling pretreatment.

[0092] 2) dyeing, soaking the PVA film after swelling treatment in a dyeing solution tank containing dichromatic dye for dyeing treatment; the dyeing solution mainly includes 2.5 wt% dichromatic dye and 1.0 wt% dyeing auxiliary, and the dichromatic dye can be a single dye or a mixture of multiple dyes.

[0093] 3) stretching, soaking the PVA film after dyeing treatment in a solution tank containing boric acid for stretching treatment; the boric acid concentration is 3.5 wt%, the tank solution temperature is 60°C, and the stretching multiple of the PVA film is 5.0.

[0094] 4) drying, washing and drying the PVA film after stretching treatment to obtain a dye-based polarizing element; the drying temperature is 80°C.

[0095] 5) primary plate curing, coating the dye-based polarizing element after drying with an adhesive on both sides, respectively, and then adhering a triacetate cellulose film, and then drying and curing the adhesive to form a thin dye-based polarizing film; the adhesive is a polyvinyl alcohol adhesive that does not yellow at high temperature (105°C). The triacetate cellulose film is a triacetate cellulose film layer with ultraviolet resistance, and the total light transmittance at 380 nm is 2%, and the thickness of the triacetate cellulose film is 40μm.

[0096] The transmittance of the prepared thin dye-based polarizing film is 42.5%, the degree of polarization is 99.2%, and the hue b is 5; the drying temperature is 125°C. Gluing, coating the dye-based polarizing primary plate with pressure-sensitive adhesive, and then compounding compensation film A; coating the side of compensation film A that is not coated with pressure-sensitive adhesive with pressure-sensitive adhesive, and then compounding compensation film B; coating the side of compensation film B that is not coated with pressure-sensitive adhesive with pressure-sensitive adhesive, and then compounding a layer of release film; obtaining a dye-based high-durability OLED polarizing sheet. The compensation film A is an A-plate type liquid crystal compensation film with a thickness of 1μm and a compensation value Re of 250nm. The optical axis angle is 60°. The compensation film B is an A-plate type liquid crystal compensation film with a thickness of 1μm and a compensation value Re of 160nm, and the optical axis angle is 5°. The thickness of the single layer of pressure-sensitive adhesive is 20μm.

[0097] Example 8.

[0098] A dye-based high-durability OLED polarizing sheet for vehicle display is prepared by the following steps.

[0099] 1) pretreatment, using a 30μm polyvinyl alcohol (PVA) film, soaking it in a first water washing tank for water washing, and then entering a swelling tank containing 1.8wt% boric acid for swelling pretreatment.

[0100] 2) dyeing, soaking the PVA film after swelling treatment in a dyeing solution tank containing dichromatic dye for dyeing treatment; the dyeing solution mainly includes 2.5wt% dichromatic dye and 1.5wt% dyeing auxiliary, and the dichromatic dye can be a single dye or a mixture of multiple dyes.

[0101] 3) stretching, soaking the PVA film after dyeing treatment in a solution tank containing boric acid for stretching treatment; the boric acid concentration is 3.5wt%, the tank solution temperature is 60°C, and the stretching multiple of the PVA film is 5.0 times.

[0102] 4) drying, washing and drying the PVA film after stretching treatment to obtain the dye-based polarizing element; the drying temperature is 80°C.

[0103] 5) primary plate curing, coating the dye-based polarizing element after drying with an adhesive on both sides, respectively, adhering a triacetate cellulose film, then drying and curing the adhesive to form a thin dye-based polarizing film; the adhesive is a polyvinyl alcohol adhesive that does not yellow at high temperature (105°C). The triacetate cellulose film is a triacetate cellulose film layer with ultraviolet resistance, the total light transmittance at 380 nm is 2%, and the thickness of the triacetate cellulose film is 40 μm.

[0104] The transmittance of the prepared thin dye-based polarizing film is 44%, the degree of polarization is 99.3%, and the hue b is 5; the drying temperature is 125°C. Gluing, coating the dye-based polarizing primary plate with pressure-sensitive adhesive, then compounding compensation film A; coating the side of compensation film A without pressure-sensitive adhesive with pressure-sensitive adhesive, then compounding compensation film B; coating the side of compensation film B without pressure-sensitive adhesive with pressure-sensitive adhesive, then compounding a layer of release film; obtaining a dye-based high-durability OLED polarizing sheet. The compensation film A is an A-plate type liquid crystal compensation film with a thickness of 1 μm and a compensation value Re of 250 nm. The optical axis angle is 60°. The compensation film B is an A-plate type liquid crystal compensation film with a thickness of 1 μm, a compensation value Re of 160 nm, and an optical axis angle of 5°. The thickness of the single layer of pressure-sensitive adhesive is 20 μm.

[0105] To better reflect the progressiveness of the present application, the following comparative tests are carried out.

[0106] Comparative Example 1: traditional iodine-based polarizing sheet, the triacetate cellulose film layer does not have ultraviolet resistance.

[0107] Comparative Example 2: traditional iodine-based polarizing sheet, the triacetate cellulose film layer has ultraviolet resistance.

[0108] Comparative Example 3: traditional dye-based polarizing sheet, the triacetate cellulose film layer does not have ultraviolet resistance.

[0109] Comparative Example 4: traditional dye-based polarizing sheet, the triacetate cellulose film layer has ultraviolet resistance.

[0110] Comparative Example 5: iodine-based OLED polarizing sheet, the triacetate cellulose film layer does not have ultraviolet resistance.

[0111] Comparative Example 6: iodine-based OLED polarizing sheet, the triacetate cellulose film layer has ultraviolet resistance.

[0112] Comparative Example 7: The polarizing sheet was prepared according to the dye 6 wt%, the auxiliary 0.45 wt%, the PVA film baking temperature 80℃, and the original plate baking temperature 140℃; other process parameters were consistent with Example 1.

[0113] Comparative Example 8: The polarizing sheet was prepared according to the dye 0025 wt%, the auxiliary 0.60 wt%, the PVA film baking temperature 90℃, and the original plate baking temperature 130℃; other process parameters were consistent with Example 1.

[0114] The performance test of the polarizing sheet prepared in each of the examples and comparative examples is shown in Table 1 and Table 2.

[0115] Table 1, dry temperature (105℃*1000h) test results

[0116] Test sample name Transmittance change rate / % Polarization change rate / % Hue bs value change rate / % Comparative Example 1 15 10 8.5 Comparative Example 2 12 8.0 13.5 Comparative Example 3 9.5 12 10 Comparative Example 4 7.0 10 6.5 Comparative Example 5 6.5 6.0 6.5 Comparative Example 6 6.5 7.0 8.0 Comparative Example 7 5.5 6.0 6.5 Comparative Example 8 5.5 6.5 6.0 This Example 1 4.5 2.5 4.0 This Example 2 4.0 2.0 3.5 This Example 3 3.5 3.0 2.5 This Example 4 3.0 2.5 3.5 This Example 5 4.5 4.0 4.5 This Example 6 4.5 3.5 4.0 This Example 7 4.5 4.5 3.5 This Example 8 4.0 4.5 5.0 .

[0117] Table 2, high temperature and high humidity (85℃*85%RH*1000h) test results

[0118] Test sample name Transmittance change rate / % Polarization change rate / % Hue bs value change rate / % Comparative Example 1 10 8 9.5 Comparative Example 2 12 8.5 11.5 Comparative Example 3 8.5 9.5 7.5 Comparative Example 4 7.0 9.0 10.5 Comparative Example 5 6.5 8.5 6.0 Comparative Example 6 6.0 10.0 7.0 Comparative Example 7 5.5 7.0 6.0 Comparative Example 8 7.0 6.5 5.5 This Example 1 4.0 2.0 3.0 This Example 2 3.5 2.5 3.5 This Example 3 3.0 3.0 1.5 This Example 4 2.5 3.0 2.0 This Example 5 3.5 3.0 4.0 This Example 6 3.5 3.0 3.5 This Example 7 4.0 3.5 4.0 This Example 8 4.5 3.5 4.5 .

[0119] As can be seen from Table 1 and Table 2, the dye-based high-durability OLED polarizing sheet prepared by the present application has excellent weather resistance and ultraviolet resistance.

[0120] The technical features of the above examples can be combined in any way, and to make the description concise, not all possible combinations of the technical features in the above examples are described, but as long as the combinations of the technical features do not contradict, they should be considered as the scope of the present application.

[0121] The above examples only express several embodiments of the present application, and the description is more specific and detailed, but it should not be understood as limiting the scope of the patent. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of variations and improvements can be made, which are within the scope of the present application. The parts not described in the specific examples are prior art or common knowledge.

[0122] In addition, it should be noted that in the description of the present application, the preferred embodiment of the present application is described in detail and the examples included can more easily understand the content of the present application. Unless otherwise defined, all technical and scientific terms used in the present application have the same meaning as generally understood by those skilled in the art. When there is a contradiction, the definition in the specification shall prevail.

[0123] In the present application, the term "prepared from" is synonymous with "comprising." As used herein, the terms "comprise," "comprising," "include," "including," "have," "having" or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises a list of elements is not necessarily limited only to those elements but can include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

[0124] In the present application, where amounts, concentrations, or other values or parameters are expressed in ranges or preferred ranges or a series of upper preferred values and lower preferred values, it is to be understood that the recited ranges are intended to include all sub-ranges, specified ranges, or preferred ranges formed from any pair of the upper and lower limits of the ranges, whether or not the ranges are explicitly disclosed. For example, where a range of "1 to 5" is disclosed, the disclosure is intended to encompass ranges of "1 to 4," "1 to 3," "1 to 2," "1 to 2 and 4 to 5," "1 to 3 and 5," etc. Where a range of numerical values is recited in the present application, unless otherwise stated, the range is intended to include the values explicitly recited as the upper and lower limits of the range and all integers and fractions within that range.

[0125] Further, the indefinite articles "a" and "an," as used herein in the specification, unless clearly indicated to the contrary, should be understood to mean "at least one." The indefinite articles "a" and "an" thus "or" should be interpreted to cover "one or at least one" or "one or more."

Claims

1. A method for preparing a dye-based high-durability OLED polarizer for vehicle-mounted display, characterized in that: The preparation steps are as follows: 1) pretreatment, the PVA film is soaked in the first water washing tank for water washing, and then enters the swelling tank containing 1.0wt%-2.5%wt boric acid for swelling pretreatment; 2) dyeing, the PVA film treated by swelling is soaked in a dyeing solution tank containing dichromatic dye for dyeing treatment; the dyeing solution contains 0.003wt%-5wt% dichromatic dye and 0.5wt%-2.5wt% dyeing auxiliary; 3) stretching, the PVA film treated by dyeing is soaked in a solution tank containing boric acid for stretching treatment; the concentration of boric acid is 1wt%-6wt%, the tank solution temperature is 25℃-65℃, and the stretching multiple of the PVA film is 3-7; 4) drying, the PVA film treated by stretching is washed and dried to obtain a dye-based polarizing element; the drying temperature is 30℃-80℃; 5) original plate curing, the dye-based polarizing element treated by drying is coated with an adhesive on the upper and lower surfaces, respectively, and then is attached to a cellulose triacetate film, and then is dried and cured to form a thin dye-based polarizing film; the drying temperature is 90℃-130℃; 6) gluing, the dye-based polarizing original plate is coated with pressure-sensitive adhesive, and then is compounded with a compensation film A; the compensation film A is coated with pressure-sensitive adhesive on the side without pressure-sensitive adhesive, and then is compounded with a compensation film B; the compensation film B is coated with pressure-sensitive adhesive on the side without pressure-sensitive adhesive, and then is compounded with a release film; In step 6), the compensation film A is an A-plate type liquid crystal compensation film, the thickness of the compensation film A is 1-5μm, the compensation value Re is 250nm-290nm, and the optical axis angle is required to be 60-90°; the compensation film B is an A-plate type liquid crystal compensation film, the thickness of the compensation film B is 1-5μm, the compensation value Re is 120nm-160nm, and the optical axis angle is 5-25°; The prepared polarizing sheet has the following optical performance requirements: transmittance is 39%-42%, degree of polarization is ≥98%, and reflectance is ≤4%; the thickness of the polarizing sheet is 130μm-270μm.

2. The preparation method of the dye-based high-durability OLED polarizing sheet for vehicle display according to claim 1, characterized in that, In step 1), the PVA film is a PVA film with a thickness of 20-40μm.

3. The preparation method of the dye-based high-durability OLED polarizing sheet for vehicle display according to claim 1, characterized in that, In step 5), the cellulose triacetate film is a cellulose triacetate film layer with ultraviolet resistance, and the ultraviolet resistance refers to that the total light spectrum transmittance at 380nm is 0-5%.

4. The preparation method of the dye-based high-durability OLED polarizing sheet for vehicle display according to claim 1, characterized in that, In step 5), the thickness of the cellulose triacetate film is 40μm-60μm.

5. The preparation method of the dye-based high-durability OLED polarizing sheet for vehicle display according to claim 1, characterized in that, In step 5), the thickness of the formed thin dye-based polarizing film is 100-130μm.

6. The method for preparing a dye-based high-durability OLED polarizing sheet for a vehicle display according to claim 1, characterized in that, In step 5), the transmittance of the formed thin dye-based polarizing film is 39%-42%, the degree of polarization is ≥98%, and the hue bs value is ±5.

7. The method for preparing a dye-based high-durability OLED polarizer for vehicle-mounted display according to claim 1, characterized in that: The prepared polarizing sheet has the following optical performance requirements: transmittance is 40%, and degree of polarization is 99%.

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