Preparation method of PVB wedge-shaped film, laminated glass and application of laminated glass

Abstract

The invention relates to the technical field of polymer films, in particular to a preparation method of a PVB wedge-shaped film, laminated glass and application of the laminated glass. The preparation method of the PVB wedge-shaped film provided by the invention comprises the following steps: preparing the following components in parts by weight: 60 to 80 parts of polyvinyl butyral, 20 to 40 parts of polyol ester compounds and 0.1 to 0.3 part of benzotriazole phenol compounds; the preparation method comprises the following steps: premixing a polyol ester compound and a benzotriazole phenolic compound to prepare a premix; wherein the pre-mixing temperature is 50 DEG C to 70 DEG C; polyvinyl butyral is heated to 70-80 DEG C, and the polyvinyl butyral and the premix are mixed in batches to prepare a mixture; and extruding the mixture to prepare the PVB wedge-shaped film. According to the preparation method, the consistency and stability of the product thickness can be guaranteed, then the PVB wedge-shaped film with good optical uniformity is prepared, the preparation method is stable and efficient, and the production efficiency can be improved.

Description

Technical Field

[0001] This application relates to the field of polymer thin film technology, specifically to a method for preparing a PVB wedge film, laminated glass, and its applications. Background Technology

[0002] A head-up display (HUD), also known as a head-up display, is an important device that projects key data such as navigation information and vehicle speed directly into the driver's field of vision, allowing the driver to obtain necessary information without looking down at the instrument panel. Because HUDs significantly reduce the frequency with which drivers look down at the instrument panel, they effectively ensure driving safety.

[0003] In the automotive industry, head-up displays (HUDs) typically utilize the windshield. Automotive windshields employ a laminated structure, consisting of two layers of glass with a polyvinyl butyral (PVB) film sandwiched between them. In this structure, because the inner and outer interfaces of the two glass layers form separate images, and these two images are positioned differently and have similar brightness, ghosting occurs, interfering with the driver's information acquisition. To solve this problem, the industry commonly uses a wedge-shaped PVB film with a wedge angle. Applying this to laminated glass, by altering the optical path, effectively adjusts the position of the outer glass image, merging the two images into one, thereby eliminating ghosting and improving the clarity and reliability of the HUD system.

[0004] Currently, in the production process of PVB wedge films, various factors such as temperature variations during raw material selection, proportioning, and mixing processes make it difficult to effectively control the consistency and stability of product thickness. Poor thickness consistency and stability lead to inconsistent light propagation characteristics, causing aberrations and abnormal light propagation in the PVB wedge film, resulting in disrupted optical stability and impacting product quality. Furthermore, current PVB wedge film preparation methods also suffer from low production efficiency. Summary of the Invention

[0005] Based on this, this application provides a method for preparing a PVB wedge film, laminated glass, and its applications. The preparation method provided by this application can ensure the consistency and stability of the product thickness, thereby obtaining a PVB wedge film with good optical uniformity. Moreover, this preparation method is stable and efficient, which can improve production efficiency.

[0006] A first aspect of this application provides a method for preparing a PVB wedge-shaped film, comprising the following steps:

[0007] Prepare the following components by weight: 60-80 parts of polyvinyl butyral, 20-40 parts of polyol ester compounds, and 0.1-0.3 parts of benzotriazole phenol compounds.

[0008] The polyol ester compound and the benzotriazole phenol compound are premixed to prepare a premix; wherein the premixing temperature is 50℃~70℃.

[0009] The polyvinyl butyral is heated to 70°C~80°C, and the polyvinyl butyral and the premix are mixed in batches to prepare a mixture;

[0010] The mixture is extruded to prepare the PVB wedge film.

[0011] In one embodiment, in the step of batch mixing the polyvinyl butyral and the premix, the temperature of the premix is ​​50°C to 70°C.

[0012] In one embodiment, the step of batch mixing the polyvinyl butyral and the premix includes: feeding the polyvinyl butyral and the premix according to weight parts and then mixing them; wherein the mixing temperature is 35°C to 45°C.

[0013] In one embodiment, the step of extruding the mixture to prepare the PVB wedge film includes:

[0014] Obtain the preset dimensions of each position of the wedge film, and adjust the extrusion process parameters of each position according to the preset dimensions to prepare the PVB wedge film; wherein, the extrusion process parameters include one or more of extrusion pressure, extrusion temperature, extrusion speed, extrusion amount and die opening gap.

[0015] In one embodiment, the preset size satisfies one or more of the following characteristics:

[0016] (1) The wedge angle of the wedge-shaped membrane is <1 mrad;

[0017] (2) The transverse wedge-shaped section of the wedge-shaped membrane includes a thick end and a thin end; the thickness of the thick end is 1.2mm~1.5mm; the thickness of the thin end is 0.5mm~0.8mm.

[0018] In one embodiment, the extrusion process parameters satisfy one or more of the following characteristics:

[0019] (1) The extrusion pressure is 40 bar to 60 bar;

[0020] (2) The extrusion temperature is 150℃~240℃;

[0021] (3) The extrusion speed is 40 r / min to 70 r / min;

[0022] (4) The extrusion rate is 10 kg / min to 20 kg / min;

[0023] (5) The mold opening gap corresponding to the thick end of the wedge-shaped membrane is 1.2mm~1.5mm; the mold opening gap corresponding to the thin end of the wedge-shaped membrane is 0.5mm~0.8mm.

[0024] In one embodiment, the polyvinyl butyral has one or more of the following characteristics:

[0025] (1) The melt index of the polyvinyl butyral is 0.8 g / 10 min to 1.2 g / 10 min;

[0026] (2) The mass fraction of hydroxyl groups in the polyvinyl butyral is 17%~20%.

[0027] In one embodiment, the polyol ester compound includes one or more compounds having the structure shown in formula (I):

[0028] ;

[0029] Where n1, n2, n3 and n4 are each an integer from 1 to 10; m is an integer from 1 to 6.

[0030] In one embodiment, the benzotriazole phenolic compound includes one or more compounds having the structure shown in formula (II):

[0031] ;

[0032] Where X is a halogen; each time R appears, it is an alkyl group of C1 to C6; q is any integer from 1 to 4.

[0033] A second aspect of this application provides a laminated glass comprising a wedge-shaped film and a glass sheet stacked together, wherein the wedge-shaped film is prepared by the preparation method described in any embodiment of the first aspect of this application.

[0034] A third aspect of this application provides an application of laminated glass in the fields of architecture, automotive, aerospace, electronic equipment, or solar photovoltaic.

[0035] The method for preparing the PVB wedge-shaped film in this application has at least the following advantages:

[0036] In the preparation method provided in this application, each raw material is first weighed in specific weight proportions. At this time, the proportion of each component is precisely controlled, which can ensure that the raw materials react fully and uniformly, thereby helping to stabilize the quality of wedge membrane products and making the production process more repeatable.

[0037] In the preparation of raw materials, polyol esters and benzotriazole phenols are premixed at a specific temperature. This reduces mixing time and energy consumption throughout the preparation process, improving production efficiency. The premix is ​​then further mixed with polyvinyl butyral heated to a specific temperature in batches. This batch mixing method promotes thorough blending and prevents uneven mixing caused by adding too much material at once. During extrusion, the uniform mixing of the compound ensures consistent flowability and plasticity throughout the process, preventing flow rate differences due to uneven component distribution. This effectively guarantees the uniformity of wedge film thickness across all parts of the extrusion process, ultimately improving the consistency of the wedge film thickness.

[0038] In summary, the preparation method provided in this application can ensure the consistency and stability of the product thickness, thereby enabling the preparation of PVB wedge films with good optical uniformity. Moreover, the preparation method is stable and efficient, which can improve production efficiency. Attached Figure Description

[0039] Figure 1 A process flow diagram of a method for preparing a PVB wedge film provided as an example in this application;

[0040] Figure 2 This is a schematic diagram of the structure of a PVB wedge-shaped membrane provided as an example in this application;

[0041] Figure 3 This is a schematic diagram of the structure of a laminated glass with a PVB wedge-shaped film provided as an example of this application.

[0042] In the figure, 1 is the PVB wedge film; 2 is the glass; 10 is the thin end; and 20 is the thick end. Detailed Implementation

[0043] The following detailed description, in conjunction with specific embodiments, provides a more complete and clear account of the preparation method of the PVB wedge film, the laminated glass, and its applications. This application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this application.

[0044] In this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0045] When a numerical range is disclosed herein, the range is considered continuous and includes the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are incorporated.

[0046] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the specification of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. Unless otherwise stated or in case of conflict, the terms or phrases used herein have the following meanings:

[0047] In this application, the terms "multiple", "various", "multiple times", "multi-dimensional", etc., unless otherwise specified, refer to a quantity greater than or equal to 2. For example, "one or more" means one or more or more.

[0048] In this application, the terms "first aspect," "second aspect," "third aspect," and "fourth aspect," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor should they be construed as implicitly indicating the importance or quantity of the indicated technical features. Moreover, "first," "second," "third," and "fourth," etc., serve only a non-exhaustive enumeration purpose and should be understood not to constitute a closed limitation on quantity.

[0049] In this application, the technical features described in an open-ended manner include both closed technical solutions consisting of the listed features and open technical solutions that include the listed features.

[0050] In this application, the terms "combinations thereof", "any combination thereof", and "any combination thereof" include all suitable combinations of any two or more of the listed items.

[0051] In this application, the term "suitable" as used in phrases such as "suitable combination," "suitable method," and "any suitable method" refers to the ability to implement the technical solution of this application, solve the technical problem of this application, and achieve the expected technical effect of this application.

[0052] In this application, terms such as "preferred," "better," "more suitable," and "ideal" are used only to describe implementation methods or embodiments with better effects, and should be understood not to constitute a limitation on the scope of protection of this application.

[0053] In this application, terms such as "further," "even further," and "particularly" are used for descriptive purposes to indicate differences in content, but should not be construed as limiting the scope of protection of this application.

[0054] In this application, the terms "optionally," "optionally," and "optional" refer to options that are optional, meaning they can be selected from either "with" or "without." If multiple "optional" options appear in a technical solution, unless otherwise specified and there are no contradictions or mutual constraints, each "optional" option is independent.

[0055] In this application, numerical intervals (i.e., numerical ranges) are involved. Unless otherwise specified, the selected numerical distributions within the aforementioned numerical intervals are considered continuous and include the two endpoints (i.e., the minimum and maximum values) of the numerical range, as well as every value between these two endpoints. Unless otherwise specified, when a numerical interval refers only to integers within that interval, it includes the two endpoint integers of the numerical range, as well as every integer between the two endpoints. In this document, this is equivalent to directly listing every integer. For example, if t is an integer selected from 1 to 10, it means that t is any integer selected from the group of integers consisting of 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10. Furthermore, when multiple ranges are provided to describe features or characteristics, these ranges can be merged. In other words, unless otherwise specified, the ranges disclosed herein should be understood to include any and all subranges to which they are included.

[0056] Unless otherwise specified, the temperature parameters in this application are permitted to be either constant-temperature treatment or variations within a certain temperature range. It should be understood that the constant-temperature treatment allows temperature fluctuations within the precision range of the instrument control, such as ±5℃, ±4℃, ±3℃, ±2℃, or ±1℃.

[0057] In this application, percentage content refers to mass percentage for solid-liquid mixtures and solid-phase-solid mixtures, and volume percentage for liquid-phase-liquid mixtures, unless otherwise specified.

[0058] In this application, unless otherwise specified, percentage concentrations refer to final concentrations. The final concentration refers to the percentage of the added component in the system after its addition.

[0059] See Figure 1 The first aspect of this application provides a method for preparing a PVB wedge film, comprising the following steps:

[0060] S10: Prepare the following components in the following weight proportions: 60-80 parts of polyvinyl butyral, 20-40 parts of polyol ester compounds, and 0.1-0.3 parts of benzotriazole phenol compounds.

[0061] S20: The polyol ester compound and the benzotriazole phenol compound are premixed to prepare a premix; wherein the premixing temperature is 50℃~70℃.

[0062] S30: The polyvinyl butyral is heated to 70℃~80℃, and the polyvinyl butyral and the premix are mixed in batches to prepare a mixture.

[0063] S40: Extrude the mixture to prepare the PVB wedge film.

[0064] The polyvinyl butyral content is 60 to 80 parts by weight. As a base material for wedge films, it can impart good flexibility, transparency, and mechanical properties to the wedge films. For example, the weight parts of polyvinyl butyral include, but are not limited to, 60, 62, 65, 68, 70, 72, 75, 78, or 80 parts, or any two of the above values ​​as endpoints.

[0065] The polyol ester compound, in parts by weight of 20 to 40, improves the flexibility and processability of the wedge membrane. For example, the parts by weight of the polyol ester compound include, but are not limited to, 20, 22, 24, 26, 28, or 30 parts, or any two of the above values ​​as endpoints. The benzotriazole and phenolic groups contained in the benzotriazole phenolic compound efficiently absorb ultraviolet radiation in the main ultraviolet regions that cause aging and degradation of the wedge membrane: UV-A (320 nm to 400 nm) and UV-B (280 nm to 320 nm) bands, converting it into harmless heat energy, thereby effectively ensuring the performance stability of the wedge membrane. For example, the parts by weight of the benzotriazole phenolic compound include, but are not limited to, 0.1, 0.15, 0.2, 0.25, 0.28, or 0.3 parts, or any two of the above values ​​as endpoints.

[0066] This application finds that direct feeding of polyol ester compounds can easily cause instability in the performance of wedge membranes. Therefore, in the preparation method provided in this application, each raw material is first batched in a specific weight proportion. At this time, precise control of the proportion of each component can ensure that the raw materials react fully and uniformly, thereby helping to stabilize the quality of wedge membrane products and making the production process more repeatable.

[0067] In step S20, the polyol ester compound and the benzotriazole phenol compound are premixed at a specific temperature. This reduces the mixing time and energy consumption in the entire preparation process, thereby improving production efficiency. Understandably, in this premixing step, the weight proportions of the polyol ester compound and the benzotriazole phenol compound are as shown in step S10. Limiting the premixing temperature helps to shorten the mixing uniformity and stability of the polyol ester compound and the benzotriazole phenol compound, and also shortens the mixing time. Simultaneously, this premixing temperature allows the premix to reach the preset temperature for batch mixing, thereby improving the stability of batch mixing and the stability of subsequent extrusion performance. For example, the premixing temperature includes, but is not limited to, 50°C, 52°C, 55°C, 58°C, 60°C, 62°C, 65°C, 68°C, or 70°C, or any two of the above values ​​as endpoints. Further, the premixing time is 1 h to 3 h. For example, the premixing time includes, but is not limited to, 1 h, 1.5 h, 2 h, 2.5 h, or 3 h.

[0068] Furthermore, in the step of batch mixing the polyvinyl butyral and the premix, the temperature of the premix is ​​50℃~70℃. In the batch mixing step, independent and precise temperature control of each raw material is beneficial to improving the stability of the batch mixing. This application has found that excessively low or high raw material temperatures for polyol esters and benzotriazole phenols can cause uneven density in the batch mixture, thereby affecting the extrusion stability of the mixture. It is understood that in this application, batch mixing refers to gradual mixing.

[0069] In one example, the batch mixing method in step S30 includes, but is not limited to, simultaneous feeding. That is, polyvinyl butyral and the premix are fed separately, and then the polyvinyl butyral and the premix are gradually mixed after feeding.

[0070] In one example, the step of batch mixing the polyvinyl butyral and the premix includes: feeding the polyvinyl butyral and the premix according to weight parts and then mixing them; wherein the mixing temperature is 35°C to 45°C. For example, the mixing temperature includes, but is not limited to, 35°C, 38°C, 40°C, 42°C, 43°C, or 45°C.

[0071] In one example, the step of extruding the mixture to prepare the PVB wedge film includes:

[0072] Obtain the preset dimensions of each position of the wedge film, and adjust the extrusion process parameters of each position according to the preset dimensions to prepare the PVB wedge film.

[0073] The extrusion process parameters include one or more of the following: extrusion pressure, extrusion temperature, extrusion speed, extrusion rate, and die opening gap.

[0074] In one example, the preset size satisfies the condition that the wedge angle of the wedge membrane is less than 1 mrad.

[0075] In this application, "wedge angle" refers to the angle between the two sides of the wedge-shaped membrane. For example, a wedge angle < 1 mrad means that the angle formed by the two sides of the wedge-shaped membrane is less than 1 mrad. Further, 0.1 mrad < wedge angle < 1 mrad.

[0076] See Figure 2 In one example, the transverse wedge-shaped section of the wedge membrane 1 includes a thick end 20 and a thin end 10.

[0077] The thickness of the thick end 20 is 1.2 mm to 1.5 mm. The thickness of the thin end 10 is 0.5 mm to 0.8 mm. For example, the thickness of the thick end 20 includes, but is not limited to, 1.2 mm, 1.3 mm, 1.4 mm or 1.5 mm. The thickness of the thin end 10 includes, but is not limited to, 0.5 mm, 0.6 mm, 0.7 mm or 0.8 mm.

[0078] In one example, the extrusion process parameters include an extrusion pressure of 40 bar to 60 bar. For example, the extrusion pressure includes, but is not limited to, 40 bar, 45 bar, 48 bar, 50 bar, 55 bar, 58 bar, or 60 bar.

[0079] In one example, the extrusion process parameters include: an extrusion temperature of 150°C to 240°C; and extrusion pressures including, but not limited to, 150°C, 160°C, 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, 230°C, or 240°C.

[0080] In one example, the extrusion process parameters include an extrusion speed of 40 r / min to 70 r / min. Extrusion speeds include, but are not limited to, 40 r / min, 42 r / min, 45 r / min, 48 r / min, 50 r / min, 52 r / min, 55 r / min, 58 r / min, or 60 r / min.

[0081] In one example, the extrusion process parameters include an extrusion rate of 10 kg / min to 20 kg / min. Extrusion rates include, but are not limited to, 10 kg / min, 12 kg / min, 14 kg / min, 16 kg / min, 18 kg / min, and 20 kg / min.

[0082] In one example, the extrusion process parameters include: the die opening gap corresponding to the thick end of the wedge film is 1.2mm~1.5mm; and the die opening gap corresponding to the thin end of the wedge film is 0.5mm~0.8mm.

[0083] This application discovers that by limiting the process parameters in the above-mentioned extrusion step and adjusting these parameters within the aforementioned range, the film thickness during extrusion can be effectively controlled, ensuring it meets the preset dimensions of the wedge-shaped film. This application also discovers that the PVB wedge-shaped film obtained through the above preparation method exhibits a thickness variation deviation of ≤1.5%. Furthermore, this application, through multi-faceted control of extrusion process parameters such as extrusion speed (e.g., extruder speed), extrusion temperature (e.g., temperature in the melt pump), and die opening gap, achieves more stable film thickness control compared to controlling a single extrusion process parameter, resulting in an approximately 15% improvement in thickness stability; therefore, the risk of optical deformation in the prepared wedge-shaped film is also lower.

[0084] Understandably, in this application, the steps of adjusting the extrusion process parameters at each position according to the preset size mainly include: testing the size of each position of the wedge film, comparing the size of each position with the preset size, and adjusting the extrusion process parameters at each position based on the comparison value.

[0085] In the preparation method provided in this application, the mixture is made uniform by limiting the weight proportions of each raw material and using a batch mixing method. During the mixing process, the temperature of the prepared mixture is 35℃~45℃, at which point the mixture is stable when fed into the extruder. By further limiting the parameters of the extrusion process, such as the melt under a specific extrusion pressure passing through the die head and being shaped into a wedge by the die lip, a wedge-shaped film can be continuously and stably produced. Under a projection lamp, the wedge-shaped film prepared by the method of this application has no deformed points or areas of bending deformation, and its optical properties are excellent.

[0086] In one example, the melt index of the polyvinyl butyral is 0.8 g / 10 min to 1.2 g / 10 min. Polyvinyl butyral with a melt index in the range of 0.8 g / 10 min to 1.2 g / 10 min exhibits suitable flowability, which allows for better uniform distribution and filling of the mold cavity during mixing with other components and extrusion. This contributes to improving the forming quality and dimensional accuracy of the wedge film, ensuring production efficiency and product consistency. For example, the melt index of polyvinyl butyral includes, but is not limited to, 0.8 g / 10 min, 0.9 g / 10 min, 1 g / 10 min, 1.1 g / 10 min, or 1.2 g / 10 min.

[0087] In one example, the mass fraction of hydroxyl groups in the polyvinyl butyral is 17% to 20%. Examples of hydroxyl mass fractions include, but are not limited to, 17%, 18%, 18.3%, 18.5%, 18.8%, 19%, or 20%.

[0088] On the one hand, the presence of hydroxyl groups can improve the compatibility of polyvinyl butyral with additives such as polyol esters and benzotriazole phenols, making the components more uniformly dispersed during the mixing process and forming a stable system. On the other hand, an appropriate hydroxyl content helps to improve the mechanical and optical properties of the wedge film, giving it better overall performance and meeting the needs of different application scenarios.

[0089] In one example, the polyol ester compound includes one or more compounds having the structure shown in formula (I):

[0090] .

[0091] Where n1, n2, n3, and n4 are each an independent integer from 1 to 10. For example, n1, n2, n3, and n4 are each an independent integer of 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10.

[0092] m is any integer from 1 to 6. m can be 1, 2, 3, 4, 5, or 6.

[0093] In one example, m is 3, n1 is 3, n2 is 1, n3 is 3, and n4 is 1. Further, the polyol ester compound is... Wedge-shaped films were prepared by compounding triethylene glycol diisooctanoate with polyvinyl butyral and benzotriazole phenolic compounds. The ester groups (-COO-) and other functional groups in the triethylene glycol diisooctanoate molecule possess good flexibility and do not form significant phase separation or crystallization regions in the wedge-shaped film, thereby reducing light scattering and ensuring high transparency. Simultaneously, the relatively stable molecular structure of triethylene glycol diisooctanoate also contributes to maintaining the stability of the film's optical properties.

[0094] In one example, the benzotriazole phenolic compounds include one or more compounds having the structure shown in formula (II):

[0095] ;

[0096] Where X is a halogen; each time R appears, it is an independent C1~C6 alkyl group; q is any integer from 1 to 4. q can be 1, 2, 3 or 4.

[0097] In this application, "halogen" refers to F, Cl, Br, or I.

[0098] In this application, "alkyl" refers to a saturated hydrocarbon group containing a primary (normal) carbon atom, or a secondary carbon atom, or a tertiary carbon atom, or a quaternary carbon atom, or a combination thereof. Phrases containing this term, such as "C1-C6 alkyl," refer to an alkyl group containing 1 to 6 carbon atoms, and each occurrence may independently be C1 alkyl, C2 alkyl, C3 alkyl, C4 alkyl, C5 alkyl, or C6 alkyl. Suitable examples include, but are not limited to: methyl (Me, -CH3), ethyl (Et, -CH2CH3), 1-propyl (n-propyl, n-Pr, n-propyl, -CH2CH2CH3), 2-propyl (i-Pr, i-propyl, -CH(CH3)2), 1-butyl (n-butyl, n-Bu, n-butyl, -CH2CH2CH2CH3), 2-methyl-1-propyl (i-Bu, i-butyl, -CH2CH(CH3)2), 2-butyl (s-Bu, s-butyl, -CH(CH3)CH2CH3), tert-butyl (1,1-dimethylethyl, 2-methyl-2-propyl (t-Bu, t-butyl) 1-Pentyl (-C(CH3)3), 1-Pentyl (n-pentyl, n-pentyl, -CH2CH2CH2CH2CH3), 2-Pentyl (-CH(CH3)CH2CH2CH3), 3-Pentyl (-CH(CH2CH3)2), 2-Methyl-2-Butyl (-C(CH3)2CH2CH3), 3-Methyl-2-Butyl (-CH(CH3)CH(CH3)2), 3-Methyl-1-Butyl (-CH2CH2CH(CH3)2), 2-Methyl-1-Butyl (-CH2CH(CH3)CH2CH3), 1-Hexyl (n-hexyl, -CH2CH2CH2CH2CH2CH3).

[0099] Furthermore, benzotriazole phenolic compounds are The hydroxyl groups in the benzotriazole phenolic compounds described above enhance intermolecular forces, improving film uniformity, reducing light scattering, and increasing transparency. The benzotriazole group influences the conjugated molecular structure, absorbing ultraviolet light and converting it into harmless heat, thereby improving the stability of the PVB wedge film.

[0100] See Figure 3 In a second aspect, this application provides a laminated glass comprising a wedge-shaped film and a glass sheet stacked together, wherein the wedge-shaped film is prepared by the preparation method described in any example of the first aspect of this application.

[0101] Furthermore, the laminated glass comprises two layers of glass 2 and a wedge-shaped film 1 disposed between the two layers of glass 2.

[0102] The following specific examples illustrate this application in detail. It should also be understood that the following examples are for further explanation only and should not be construed as limiting the scope of protection of this application. Any non-essential improvements and adjustments made by those skilled in the art based on the above description of this application fall within the scope of protection of this application. The specific process parameters, etc., in the following examples are merely examples within a suitable range; that is, those skilled in the art can make appropriate selections within the appropriate range based on the description herein, and are not necessarily limited to the specific values ​​in the examples below.

[0103] Example 1

[0104] Example 1 provides a method for preparing a PVB wedge film, comprising the following steps:

[0105] (1) Prepare the raw materials according to the following components in parts by weight: 70 parts of polyvinyl butyral (melt index 1g / 10min, hydroxyl mass fraction 18%), polyol ester compounds 30 samples, and benzotriazole phenolic compounds 0.2 copies.

[0106] (2) The polyol ester compound and the benzotriazole phenol compound were premixed at 60°C for 1 hour according to the weight ratio to prepare a premix;

[0107] (3) The polyvinyl butyral is heated to 70°C, and the polyvinyl butyral and the premix (60°C) are fed simultaneously and then mixed at 40°C to prepare a mixture;

[0108] (4) Extrude the mixture, test the dimensions of each position of the wedge film, compare the dimensions of each position with the preset dimensions, and adjust the extrusion process parameters of each position based on the comparison values.

[0109] The process parameters were adjusted as follows: extrusion of the mixture, extrusion pressure of 40 bar, extrusion temperature of 180℃, extrusion speed of 40 r / min, extrusion rate of 10 kg / min, and die opening gap of 1.2 mm for the thick end of the wedge film and 0.6 mm for the thin end of the wedge film to prepare PVB wedge films. The wedge angle of the wedge film was 0.5 mrad; the transverse wedge cross-section of the wedge film included the thick end and the thin end; the thickness of the thick end was 1.2 mm; and the thickness of the thin end was 0.6 mm.

[0110] Example 2

[0111] Example 2 is basically the same as Example 1, the main difference being that the polyvinyl butyral used in Example 2 has a melt index of 1.2 g / 10 min and a hydroxyl mass fraction of 18.5%.

[0112] Example 3

[0113] Example 3 is basically the same as Example 1, the main difference being that the polyol ester compound used in Example 3 is dipropylene glycol dibenzoate. .

[0114] Example 4

[0115] Example 4 is basically the same as Example 1, the main difference being that the extrusion process parameters of Example 4 are different from those of Example 1. The extrusion process parameters of Example 4 are as follows:

[0116] The mixture was extruded at an extrusion pressure of 45 bar, an extrusion temperature of 170℃, an extrusion speed of 55 r / min, and an extrusion rate of 14 kg / min. The die opening gap corresponding to the thick end of the wedge film was 1.3 mm, and the die opening gap corresponding to the thin end of the wedge film was 1.0 mm, to prepare a PVB wedge film. The preset wedge angle of the wedge film was 0.25 mrad. The transverse wedge cross-section of the wedge film included a thick end and a thin end; the preset thickness of the thick end was 1.3 mm, and the preset thickness of the thin end was 1.0 mm.

[0117] Comparative Example 1

[0118] Comparative Example 1 is basically the same as Example 1, the main difference being that the weight parts of each raw material in Comparative Example 1 are different from those in Example 1. Specifically, the weight parts of each raw material in Comparative Example 1 are 100 parts of polyvinyl butyral, 10 parts of polyol ester compound, and 0.6 parts of benzotriazole phenol compound.

[0119] Comparative Example 2

[0120] (1) Prepare the raw materials according to the following components in parts by weight: 70 parts of polyvinyl butyral (melt index 1g / 10min, hydroxyl mass fraction 18%), polyol ester compounds 30 samples, and benzotriazole phenolic compounds 0.2 copies.

[0121] (2) The polyvinyl butyral, polyol ester compounds, and benzotriazole phenol compounds are mixed in one step, and then mixed at 50°C to prepare a mixture;

[0122] (3) Extrude the mixture, test the dimensions of each position of the wedge film, compare the dimensions of each position with the preset dimensions, and adjust the extrusion process parameters of each position based on the comparison values.

[0123] The process parameters were adjusted as follows: extrusion of the mixture, extrusion pressure of 50 bar, extrusion temperature of 210℃, extrusion speed of 70 r / min, extrusion rate of 20 kg / min, and die opening gap of 1.2 mm for the thick end of the wedge film and 0.6 mm for the thin end of the wedge film to prepare PVB wedge films. The wedge angle of the wedge film was 0.5 mrad; the transverse wedge cross-section of the wedge film included the thick end and the thin end; the thickness of the thick end was 1.2 mm; and the thickness of the thin end was 0.6 mm.

[0124] The prepared wedge-shaped membrane was subjected to sample testing. Specifically, the test included: the cross-sectional width of the wedge-shaped membrane was 1200 mm, and thickness measurements were taken at 100 mm intervals at points of 0 mm (corresponding to the thin end), 100 mm, 200 mm, 300 mm, 400 mm, 500 mm, 600 mm, 700 mm, 800 mm, 900 mm, 1000 mm, 1100 mm, and 1200 mm (corresponding to the thick end). The wedge angle was then calculated based on each thickness to obtain the wedge angle error. The wedge angle β was calculated as: [(thickness at point mm - thickness at thin end mm) / distance between point and thin end mm] × 1000, with the unit of wedge angle being mrad.

[0125] The corresponding test results are shown in Table 1.

[0126] Table 1

[0127]

[0128] Table 2

[0129]

[0130] Table 3

[0131]

[0132] Table 4

[0133]

[0134] Table 5

[0135]

[0136] Table 6

[0137]

[0138] As can be seen from Tables 1 to 6, the wedge angle error of the wedge membrane prepared in the embodiments of this application is relatively small.

[0139] The technical features in the examples described above can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the examples are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0140] The examples described above merely illustrate several implementation methods of this application to facilitate a detailed understanding of the technical solutions of this application, but should not be construed as limiting the scope of protection of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. It should be understood that technical solutions obtained by those skilled in the art based on the technical solutions provided in this application through logical analysis, reasoning, or limited experimentation are all within the scope of protection of the appended claims. Therefore, the scope of protection of this patent application should be determined by the content of the appended claims, and the specification can be used to interpret the content of the claims.

Claims

1. A method for preparing a PVB wedge-shaped film, characterized in that, Includes the following steps: Prepare the following components by weight: 60-80 parts of polyvinyl butyral, 20-40 parts of polyol ester compounds, and 0.1-0.3 parts of benzotriazole phenol compounds. The polyol ester compound and the benzotriazole phenol compound are premixed to prepare a premix; wherein the premixing temperature is 50℃~70℃. The polyvinyl butyral is heated to 70°C~80°C, and the polyvinyl butyral and the premix are mixed in batches to prepare a mixture; The mixture is extruded to prepare the PVB wedge film.

2. The method for preparing the PVB wedge-shaped film according to claim 1, characterized in that, In the step of mixing the polyvinyl butyral and the premix in batches, the temperature of the premix is ​​50°C to 70°C. And / or, the step of batch mixing the polyvinyl butyral and the premix includes: feeding the polyvinyl butyral and the premix according to the weight parts and then mixing them; wherein the mixing temperature is 35℃~45℃.

3. The method for preparing the PVB wedge-shaped film according to claim 1 or 2, characterized in that, The step of extruding the mixture to prepare the PVB wedge film includes: Obtain the preset dimensions of each position of the wedge film, and adjust the extrusion process parameters of each position according to the preset dimensions to prepare the PVB wedge film; wherein, the extrusion process parameters include one or more of extrusion pressure, extrusion temperature, extrusion speed, extrusion amount and die opening gap.

4. The method for preparing the PVB wedge-shaped film according to claim 3, characterized in that, The preset size satisfies one or more of the following characteristics: (1) The wedge angle of the wedge-shaped membrane is <1 mrad; (2) The transverse wedge-shaped section of the wedge-shaped membrane includes a thick end and a thin end; the thickness of the thick end is 1.2mm~1.5mm; the thickness of the thin end is 0.5mm~0.8mm.

5. The method for preparing the PVB wedge-shaped film according to claim 3, characterized in that, The extrusion process parameters satisfy one or more of the following characteristics: (1) The extrusion pressure is 40 bar to 60 bar; (2) The extrusion temperature is 150℃~240℃; (3) The extrusion speed is 40 r / min to 70 r / min; (4) The extrusion rate is 10 kg / min to 20 kg / min; (5) The mold opening gap corresponding to the thick end of the wedge-shaped membrane is 1.2mm~1.5mm; the mold opening gap corresponding to the thin end of the wedge-shaped membrane is 0.5mm~0.8mm.

6. The method for preparing the PVB wedge-shaped film according to claim 1 or 2, characterized in that, The polyvinyl butyral has one or more of the following characteristics: (1) The melt index of the polyvinyl butyral is 0.8 g / 10 min to 1.2 g / 10 min; (2) The mass fraction of hydroxyl groups in the polyvinyl butyral is 17%~20%.

7. The method for preparing the PVB wedge-shaped film according to claim 1 or 2, characterized in that, The polyol ester compounds include one or more compounds having the structure shown in formula (I): ； Where n1, n2, n3 and n4 are each an integer from 1 to 10; m is an integer from 1 to 6.

8. The method for preparing the PVB wedge-shaped film according to claim 1 or 2, characterized in that, Benzotriazole phenolic compounds include one or more compounds having the structure shown in formula (II): ； Where X is a halogen; each time R appears, it is an alkyl group of C1 to C6; q is any integer from 1 to 4.

9. A laminated glass, characterized in that, It includes a wedge-shaped film and a glass sheet stacked together, wherein the wedge-shaped film is prepared by the preparation method according to any one of claims 1 to 8.

10. The application of the laminated glass of claim 9 in the fields of construction, automobiles, aviation, electronic equipment, or solar photovoltaics.

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