Light adjusting glass, preparation method therefor, and application thereof

Abstract

light adjusting glass, comprising a first piece of glass, a second piece of glass, and a light adjustment film (3) arranged between the first piece of glass and the second piece of glass; a first interlayer is arranged between the first piece of glass and the light adjustment film (3), and / or a second interlayer is arranged between the second piece of glass and the light adjustment film (3); and the first interlayer is a PVB composite adhesive film (A) having a multi-layer structure. The light adjusting glass uses said PVB composite adhesive film having a multi-layer structure, where a synergistic effect of the multi-layer structure causes the PVB composite adhesive film having the multi-layer structure to have good adhesion and mechanical properties. Additionally, by performing pre-treatment on a PET surface of the dimming film (3) when manufacturing the light adjusting glass, the good bonding force between PET and an edge layer of the PVB composite adhesive film having a multi-layer structure is further strengthened, thereby enabling the light adjusting glass to possess the important attributes of being able to satisfy adhesion and aging stability requirements.

Description

A dimming glass and its preparation method and application Technical Field

[0001] The present invention belongs to the technical field of dimming glass, and relates to a dimming glass and a preparation method and application thereof, and in particular to a dimming glass whose interlayer is a PVB composite film with a multi-layer structure and a preparation method and application thereof. Background Art

[0002] Smart glass is a light-control device that primarily involves placing a smart film between two layers of transparent glass. Types of smart films include suspended particle (SPD) smart film, polymer dispersed liquid crystal (PDLC) smart film, electrochromic (EC) smart film, thermochromic (TC) smart film, and photochromic (PC) smart film. Smart glass made with suspended particle smart film, polymer dispersed liquid crystal smart film, and electrochromic smart film are called suspended particle smart glass, polymer dispersed liquid crystal smart glass, and electrochromic smart glass, respectively. For suspended particle smart glass, polymer dispersed liquid crystal smart glass, and electrochromic smart glass, when electricity is applied, the arrangement or state of the material in the smart film changes, thereby changing the light transmittance of the smart glass, such as switching from low transmittance to high transmittance, or vice versa. This type of dimming glass, which can achieve rapid conversion between on and off states through the action of electric field / current, has the advantages of actively regulating light transmittance and energy saving. The device can be used as smart windows and rearview mirrors, sunglasses, displays, etc. in spacecraft, high-speed railways, cars, buildings, etc.

[0003] Conventional PVB film (Polyvinyl butyral interlayer), the same film used in laminated glass, has been used to produce suspended particle switchable glass, polymer dispersed liquid crystal switchable glass, and electro-variable switchable glass. Conventional PVB film has a high glass transition temperature (Tg), requiring a relatively high lamination temperature for the manufacture of switchable glass. This negatively impacts the performance of these films, as well as the high hardness and rigidity of conventional PVB laminates. Furthermore, due to the high hardness and rigidity of conventional PVB laminates, residual stress can cause significant degradation of the switchable glass's dimming performance over long-term use, resulting in substandard performance.

[0004] Therefore, how to find a more suitable film material to solve the above-mentioned problem of seriously affecting the stability of the dimming glass when using conventional PVB film in the existing technology to make suspended particle dimming glass, polymer dispersed liquid crystal dimming glass, and electro-variable dimming glass, so as to meet the adhesion requirements of the dimming glass and prevent the problem of dimming performance degradation of the dimming glass has become one of the urgent problems to be solved by many front-line researchers in the industry.

[0005] Summary of the Invention

[0006] In light of this, the present invention aims to provide a smart glass, its preparation method, and its application, specifically a smart glass in which the interlayer comprises a multi-layered PVB composite film. The smart glass provided by the present invention comprises a multi-layered PVB composite film. Through the synergistic effect of the multi-layered structure, the multi-layered PVB composite film exhibits excellent adhesion and mechanical properties, thus resolving the problem of performance degradation in smart glass.

[0007] The present invention provides a dimming glass, comprising a first glass and a second glass;

[0008] and a dimming film disposed between the first glass and the second glass;

[0009] A first interlayer is provided between the first glass and the dimming film, and / or a second interlayer is provided between the second glass and the dimming film;

[0010] The first interlayer is a PVB composite film A having a multi-layer structure;

[0011] The multi-layer PVB composite film A contains at least one PVB layer with a glass transition temperature Tg≤45°C, denoted as Tg min PVB layer, and at least one PVB layer with a glass transition temperature Tg ≥ 50 ° C, denoted as Tg max PVB layer; and Tg max -Tg min ≥15℃.

[0012] Preferably, the second interlayer is a PVB composite film B with a multi-layer structure;

[0013] The multi-layer PVB composite film B contains at least one PVB layer with a glass transition temperature Tg≤45°C, denoted as Tg min PVB layer, and at least one PVB layer with a glass transition temperature Tg ≥ 50 ° C, denoted as Tg max PVB layer; and Tg max -Tg min ≥15℃.

[0014] Preferably, the Tg min The PVB layer is prepared from raw materials including a polyvinyl butyral resin having a weight average molecular weight of 100,000 to 200,000 and a plasticizer;

[0015] The Tg min The melt mass flow rate of the polyvinyl butyral resin in the raw material of the PVB layer is 5.0 to 10.0 g / 10 minutes;

[0016] The Tg minThe mass content of the plasticizer in the raw materials of the PVB layer is 35wt% to 65wt%.

[0017] Preferably, the Tg min The plasticizer in the raw material of the PVB layer includes a phthalate plasticizer and / or a trimellitic acid ester plasticizer.

[0018] Preferably, the Tg max The PVB layer is prepared from raw materials including a polyvinyl butyral resin having a weight average molecular weight of 100,000 to 200,000 and a plasticizer;

[0019] The Tg max The melt mass flow rate of the polyvinyl butyral resin in the raw material of the PVB layer is 2.0 to 4.0 g / 10 minutes;

[0020] The Tg max The mass content of the plasticizer in the raw materials of the PVB layer is 10 wt% to 35 wt%.

[0021] Preferably, the Tg max The plasticizer in the raw material of the PVB layer includes an aliphatic ester plasticizer.

[0022] Preferably, the PVB composite film having a multi-layer structure is a PVB composite film having a two-layer structure;

[0023] The two-layer PVB composite film specifically includes an upper PVB layer facing the dimming film and a lower PVB layer facing the glass;

[0024] The upper PVB layer is Tg min PVB layer, the lower PVB layer is Tg max PVB layer;

[0025] The thickness ratio of the upper PVB layer to the lower PVB layer is (1.0-2.0):1.

[0026] Preferably, the upper PVB layer is prepared from raw materials comprising a polyvinyl butyral resin having a weight average molecular weight of 100,000 to 200,000 and a plasticizer;

[0027] The melt mass flow rate of the polyvinyl butyral resin in the raw material of the upper PVB layer is 5.0 to 10.0 g / 10 minutes;

[0028] The mass content of the plasticizer in the raw materials of the upper PVB layer is 35 wt % to 65 wt %.

[0029] Preferably, the plasticizer in the raw material of the upper PVB layer includes phthalate plasticizer and / or trimellitic acid ester plasticizer.

[0030] Preferably, the lower PVB layer is prepared from raw materials comprising a polyvinyl butyral resin having a weight average molecular weight of 100,000 to 200,000 and a plasticizer;

[0031] The melt mass flow rate of the polyvinyl butyral resin in the raw material of the lower PVB layer is 2.0 to 4.0 g / 10 minutes;

[0032] The mass content of the plasticizer in the raw materials of the lower PVB layer is 10 wt% to 35 wt%.

[0033] Preferably, the plasticizer in the raw material of the lower PVB layer includes an aliphatic ester plasticizer.

[0034] Preferably, the raw material of the lower PVB layer also contains a UV absorber;

[0035] The mass content of the UV absorber in the raw materials of the lower PVB layer is 0.1wt% to 5wt%;

[0036] The UV absorber includes one or more of salicylate UV absorbers, benzophenone UV absorbers, benzotriazole UV absorbers, triazine UV absorbers, trimethoxybenzoate UV absorbers, p-aminobenzoic acid UV absorbers, phenyl cinnamate UV absorbers, camphor derivative UV absorbers, benzamidine UV absorbers and benzoxazine UV absorbers.

[0037] Preferably, the raw materials of the lower PVB layer also contain an IR absorber;

[0038] The mass content of the IR absorber in the raw materials of the lower PVB layer is 0.1wt% to 5wt%;

[0039] The IR absorbers include metal compounds and / or carbides.

[0040] Preferably, the PVB composite adhesive film having a multi-layer structure is a PVB composite adhesive film having a three-layer structure;

[0041] The three-layer PVB composite film specifically includes two side PVB layers and a middle PVB layer;

[0042] One or both of the two side PVB layers are Tg min PVB layer;

[0043] The intermediate PVB layer is Tg max PVB layer.

[0044] Preferably, one or both of the two edge PVB layers are prepared from raw materials comprising a polyvinyl butyral resin having a weight average molecular weight of 100,000 to 200,000 and a plasticizer;

[0045] The Tg min The melt mass flow rate of the polyvinyl butyral resin in the raw material of the PVB layer is 5.0 to 10.0 g / 10 minutes;

[0046] The Tg min The mass content of the plasticizer in the raw materials of the PVB layer is 35 wt% to 65 wt%.

[0047] Preferably, the plasticizer in the raw materials of one or both of the two edge PVB layers includes phthalate plasticizer and / or trimellitic acid plasticizer.

[0048] Preferably, in the two side PVB layers, the thickness ratio of the first side PVB layer to the second side PVB layer is (1.0-2.0):1;

[0049] The thickness of one of the two side PVB layers accounts for 1% to 25% of the total thickness of the PVB layer of the three-layer structure.

[0050] Preferably, the intermediate PVB layer is prepared from raw materials comprising a polyvinyl butyral resin having a weight average molecular weight of 100,000 to 200,000 and a plasticizer;

[0051] The melt mass flow rate of the polyvinyl butyral resin in the raw material of the intermediate PVB layer is 2.0 to 4.0 g / 10 minutes;

[0052] The mass content of the plasticizer in the raw materials of the intermediate PVB layer is 10 wt% to 35 wt%.

[0053] Preferably, the plasticizer in the raw material of the intermediate PVB layer includes an aliphatic ester plasticizer.

[0054] Preferably, the raw materials of the intermediate PVB layer also contain a UV absorber;

[0055] The mass content of the UV absorber in the raw materials of the intermediate PVB layer is 0.1wt% to 5wt%;

[0056] The UV absorber includes one or more of salicylate UV absorbers, benzophenone UV absorbers, benzotriazole UV absorbers, triazine UV absorbers, trimethoxybenzoate UV absorbers, p-aminobenzoic acid UV absorbers, phenyl cinnamate UV absorbers, camphor derivative UV absorbers, benzamidine UV absorbers and benzoxazine UV absorbers.

[0057] Preferably, the raw materials of the intermediate PVB layer also contain an IR absorber;

[0058] The mass content of the IR absorber in the raw materials of the intermediate PVB layer is 0.1wt% to 5wt%;

[0059] The IR absorbers include metal compounds and / or carbides.

[0060] Preferably, at least one of the two outer surfaces of the multi-layered PVB composite adhesive film is provided with a roll-formed pattern.

[0061] Preferably, the first glass is transparent glass;

[0062] The second glass is transparent glass;

[0063] The glass is selected from inorganic glass and / or organic glass.

[0064] Preferably, the dimming film is selected from one or more of a suspended particle dimming film, a polymer dispersed liquid crystal dimming film and an electrochromic dimming film.

[0065] The present invention provides a method for preparing the switchable glass according to any one of the above technical solutions, comprising the following steps:

[0066] 1) Pre-treat the PET surfaces on both sides of the dimming film;

[0067] 2) After stacking the layers according to the structure of the dimming glass, perform a lamination process.

[0068] Preferably, the temperature of the lamination treatment is 90-120°C.

[0069] Preferably, the pretreatment method includes corona treatment and / or plasma treatment.

[0070] Preferably, the pretreatment method includes: firstly coating a solution containing polyvinyl butyral resin on the PET surfaces on both outer sides of the dimming film, and then drying the solvent.

[0071] Preferably, the pretreatment method includes: first performing corona treatment and / or plasma treatment on the PET surfaces on both sides of the dimming film, then coating the PET surface with a solution containing polyvinyl butyral resin, and then drying the solvent.

[0072] Preferably, the solution containing polyvinyl butyral resin comprises polyvinyl butyral resin and an organic solvent;

[0073] The mass concentration of the solution containing polyvinyl butyral resin is 5%wt to 15%wt;

[0074] The weight average molecular weight of the polyvinyl butyral resin is 100,000 to 200,000.

[0075] The present invention also provides the use of the dimming glass described in any one of the above technical solutions or the dimming glass prepared by the preparation method described in any one of the above technical solutions in one or more of automobile window glass, skylight glass and glass curtain wall.

[0076] The present invention provides a dimming glass, comprising a first glass and a second glass; and a dimming film arranged between the first glass and the second glass; a first interlayer is arranged between the first glass and the dimming film, and / or a second interlayer is arranged between the second glass and the dimming film; the first interlayer is a PVB composite adhesive film A having a multi-layer structure; the multi-layer PVB composite adhesive film A contains at least one PVB layer with a glass transition temperature Tg≤45°C, denoted as Tg min PVB layer, and at least one PVB layer with a glass transition temperature Tg ≥ 50 ° C, denoted as Tg max PVB layer; and Tg max -Tg min ≥15°C. Compared with the prior art, the present invention creatively designs a multi-layer PVB composite film and uses it in the production of dimming glass, which solves the problem of performance degradation of dimming glass and also meets the requirements of adhesion.

[0077] The switchable glass provided by the present invention utilizes a multi-layered PVB composite film. The synergistic effect of the multi-layer structure provides the film with excellent adhesion and mechanical properties. Furthermore, pre-treating the surface of the PET film during manufacture further strengthens the adhesion between the edge layers of the multi-layered PVB composite film and the PET film. This ensures that the switchable glass meets the required adhesion and aging stability, eliminating the problem of performance degradation in the switchable glass. The present invention has significant practical significance and promising application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0078] FIG1 is a schematic structural diagram of the switchable glass provided by the present invention;

[0079] FIG2 is a schematic structural diagram of a PVB composite adhesive film having a three-layer structure provided by the present invention;

[0080] FIG3 is a photograph of the switchable glass in Comparative Example 1 of the present invention after aging at 105° C. for 216 hours. DETAILED DESCRIPTION

[0081] In order to further understand the present invention, preferred embodiments of the present invention are described below in conjunction with examples. However, it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, rather than for limiting the claims of the invention.

[0082] All raw materials of the present invention are not particularly limited in their sources and can be purchased from the market or prepared according to conventional methods well known to those skilled in the art.

[0083] There is no particular limitation on the purity of all raw materials in the present invention. The present invention preferably uses analytically pure materials or materials of conventional purity used in the field of dimming glass preparation.

[0084] In the present invention, the following adhesive film is an adhesive film layer or a layer, and the adhesive film has the concept and structure of a layer, such as a PVB composite adhesive film, that is, a PVB composite layer or a PVB composite adhesive film layer.

[0085] In the present invention, the molecular weight refers to the weight average molecular weight (Mw).

[0086] The present invention provides a dimming glass, comprising a first glass and a second glass;

[0087] and a dimming film disposed between the first glass and the second glass;

[0088] A first interlayer is provided between the first glass and the dimming film, and / or a second interlayer is provided between the second glass and the dimming film;

[0089] The first interlayer is a PVB composite film A having a multi-layer structure;

[0090] The multi-layer PVB composite film A contains at least one PVB layer with a glass transition temperature Tg≤45°C, denoted as Tg min PVB layer, and at least one PVB layer with a glass transition temperature Tg ≥ 50 ° C, denoted as Tg max PVB layer; and Tg max -Tg min ≥15℃. Among them, Tg max Tg max The glass transition temperature Tg of the PVB layer, Tg min Tg min The glass transition temperature Tg of the PVB layer, Tg max -Tg min It can be ≥17°C, or ≥20°C.

[0091] In the present invention, the first glass and / or the second glass may be a glass plate or a glass layer.

[0092] In the present invention, the second interlayer is preferably a PVB composite adhesive film B having a multi-layer structure.

[0093] In the present invention, the multi-layer PVB composite film B preferably contains at least one PVB layer with a glass transition temperature Tg≤45°C (which may be Tg≤43°C or Tg≤40°C), denoted as Tg min PVB layer, and at least one PVB layer with a glass transition temperature of Tg ≥ 50 ° C (which can be Tg ≥ 53 ° C, or Tg ≥ 55 ° C), denoted as Tg max PVB layer; and Tg max -Tg min ≥15℃. Among them, Tg max Tg max The glass transition temperature Tg of the PVB layer, Tg min Tg min The glass transition temperature Tg of the PVB layer, Tg max -Tg min It can be ≥17°C, or ≥20°C.

[0094] In the present invention, the Tg min The PVB layer is preferably prepared from raw materials comprising a polyvinyl butyral resin having a weight average molecular weight of 100,000 to 200,000 and a plasticizer, more preferably from raw materials comprising a polyvinyl butyral resin having a weight average molecular weight of 120,000 to 180,000 and a plasticizer, and even more preferably from raw materials comprising a polyvinyl butyral resin having a weight average molecular weight of 140,000 to 160,000 and a plasticizer. Specifically, the preparation can be obtained by mixed extrusion.

[0095] In the present invention, the Tg min The melt mass flow rate of the polyvinyl butyral resin in the raw material of the PVB layer is preferably 5.0 to 10.0 g / 10 min, more preferably 6.0 to 9.0 g / 10 min, and even more preferably 7.0 to 8.0 g / 10 min.

[0096] In the present invention, the Tg min The mass content of the plasticizer in the raw materials of the PVB layer is preferably 35 wt% to 65 wt%, more preferably 40 wt% to 60 wt%, and even more preferably 45 wt% to 55 wt%.

[0097] In the present invention, the Tg min The plasticizer in the raw material of the PVB layer preferably includes a phthalate plasticizer and / or a trimellitic acid plasticizer.

[0098] In the present invention, the Tg maxThe PVB layer is prepared from raw materials comprising a polyvinyl butyral resin having a weight average molecular weight of 100,000 to 200,000 and a plasticizer, more preferably 120,000 to 180,000 and even more preferably 140,000 to 160,000. Specifically, the preparation may be performed by mixed extrusion.

[0099] In the present invention, the Tg max The melt mass flow rate of the polyvinyl butyral resin in the raw material of the PVB layer is 2.0 to 4.0 g / 10 minutes, more preferably 2.2 to 3.8 g / 10 minutes, and even more preferably 2.5 to 3.5 g / 10 minutes.

[0100] In the present invention, the Tg max The mass content of the plasticizer in the raw materials of the PVB layer is preferably 10 wt% to 35 wt%, more preferably 15 wt% to 30 wt%, and even more preferably 20 wt% to 25 wt%.

[0101] In the present invention, the Tg max The plasticizer in the raw material of the PVB layer preferably includes an aliphatic ester plasticizer.

[0102] In the present invention, the PVB composite adhesive film having a multi-layer structure is preferably a PVB composite adhesive film having a two-layer structure.

[0103] In the present invention, the two-layer PVB composite adhesive film preferably includes an upper PVB layer facing the dimming film and a lower PVB layer facing the glass.

[0104] In the present invention, the upper PVB layer is preferably Tg min PVB layer, the lower PVB layer is preferably Tg max PVB layer.

[0105] In the present invention, the thickness ratio of the upper PVB layer to the lower PVB layer is preferably (1.0-2.0):1, more preferably (1.2-1.8):1, and even more preferably (1.4-1.6):1.

[0106] In the present invention, the upper PVB layer is preferably prepared from raw materials comprising a polyvinyl butyral resin and a plasticizer having a weight average molecular weight of 100,000 to 200,000, more preferably prepared from raw materials comprising a polyvinyl butyral resin and a plasticizer having a weight average molecular weight of 120,000 to 180,000, and more preferably prepared from raw materials comprising a polyvinyl butyral resin and a plasticizer having a weight average molecular weight of 140,000 to 160,000.

[0107] In the present invention, the melt mass flow rate of the polyvinyl butyral resin in the raw material of the upper PVB layer is preferably 5.0 to 10.0 g / 10 minutes, more preferably 6.0 to 9.0 g / 10 minutes, and more preferably 7.0 to 8.0 g / 10 minutes.

[0108] In the present invention, the mass content of the plasticizer in the raw material of the upper PVB layer is preferably 35 wt% to 65 wt%, more preferably 40 wt% to 60 wt%, and even more preferably 45 wt% to 55 wt%.

[0109] In the present invention, the plasticizer in the raw material of the upper PVB layer preferably includes a phthalate plasticizer and / or a trimellitic ester plasticizer, and more preferably a phthalate plasticizer or a trimellitic ester plasticizer.

[0110] In the present invention, the lower PVB layer is preferably prepared from raw materials comprising a polyvinyl butyral resin and a plasticizer having a weight-average molecular weight of 100,000 to 200,000, more preferably prepared from raw materials comprising a polyvinyl butyral resin and a plasticizer having a weight-average molecular weight of 120,000 to 180,000, and more preferably prepared from raw materials comprising a polyvinyl butyral resin and a plasticizer having a weight-average molecular weight of 140,000 to 160,000.

[0111] In the present invention, the melt mass flow rate of the polyvinyl butyral resin in the raw material of the lower PVB layer is preferably 2.0 to 4.0 g / 10 min, more preferably 2.4 to 3.6 g / 10 min, and even more preferably 2.8 to 3.2 g / 10 min.

[0112] In the present invention, the mass content of the plasticizer in the raw material of the lower PVB layer is preferably 10 wt% to 35 wt%, more preferably 15 wt% to 30 wt%, and even more preferably 20 wt% to 25 wt%.

[0113] In the present invention, the plasticizer in the raw material of the lower PVB layer preferably includes an aliphatic ester plasticizer.

[0114] In the present invention, the raw materials of the lower PVB layer preferably further contain a UV absorber.

[0115] In the present invention, the mass content of the UV absorber in the raw material of the lower PVB layer is preferably 0.1 wt% to 5 wt%, more preferably 1 wt% to 4 wt%, and even more preferably 2 wt% to 3 wt%.

[0116] In the present invention, the UV absorber preferably includes one or more of a salicylate UV absorber, a benzophenone UV absorber, a benzotriazole UV absorber, a triazine UV absorber, a trimethoxybenzoate UV absorber, a p-aminobenzoic acid UV absorber, a phenyl cinnamate UV absorber, a camphor derivative UV absorber, a benzamidine UV absorber and a benzoxazine UV absorber, more preferably a salicylate UV absorber, a benzophenone UV absorber, a benzotriazole UV absorber, a triazine UV absorber, a trimethoxybenzoate UV absorber, a p-aminobenzoic acid UV absorber, a phenyl cinnamate UV absorber, a camphor derivative UV absorber, a benzamidine UV absorber or a benzoxazine UV absorber.

[0117] In the present invention, the raw material of the lower PVB layer preferably further contains an IR absorber.

[0118] In the present invention, the mass content of the IR absorber in the raw material of the lower PVB layer is preferably 0.1 wt% to 5 wt%, more preferably 1 wt% to 4 wt%, and even more preferably 2 wt% to 3 wt%.

[0119] In the present invention, the IR absorber preferably includes a metal compound and / or a carbide, more preferably a metal compound or a carbide.

[0120] In the present invention, the PVB composite adhesive film having a multi-layer structure is preferably a PVB composite adhesive film having a three-layer structure.

[0121] In the present invention, the three-layer PVB composite film preferably includes two side PVB layers and a middle PVB layer.

[0122] In the present invention, one or both of the two side PVB layers are preferably Tg min PVB layer.

[0123] In the present invention, the intermediate PVB layer is preferably Tg max PVB layer.

[0124] In the present invention, one or both of the two edge PVB layers are preferably prepared from raw materials comprising a polyvinyl butyral resin and a plasticizer having a weight-average molecular weight of 100,000 to 200,000, more preferably prepared from raw materials comprising a polyvinyl butyral resin and a plasticizer having a weight-average molecular weight of 120,000 to 180,000, and more preferably prepared from raw materials comprising a polyvinyl butyral resin and a plasticizer having a weight-average molecular weight of 140,000 to 160,000.

[0125] In the present invention, the melt mass flow rate of the polyvinyl butyral resin in the raw materials of one or both of the two edge PVB layers is preferably 5.0 to 10.0 g / 10 min, more preferably 6.0 to 9.0 g / 10 min, and more preferably 7.0 to 8.0 g / 10 min.

[0126] In the present invention, the mass content of the plasticizer in the raw materials of one or both of the two edge PVB layers is preferably 10 wt% to 35 wt%, more preferably 15 wt% to 30 wt%, and even more preferably 20 wt% to 25 wt%.

[0127] In the present invention, the plasticizer in the raw materials of one or both of the two edge PVB layers preferably includes phthalate plasticizers and / or trimellitic acid ester plasticizers, more preferably phthalate plasticizers or trimellitic acid ester plasticizers.

[0128] In the present invention, the thickness ratio of the first side PVB layer to the second side PVB layer of the two side PVB layers is preferably (1.0-2.0):1, more preferably (1.2-1.8):1, and even more preferably (1.4-1.6):1. Specifically, of the two side PVB layers, the PVB film layer facing the dimming film is preferably thicker.

[0129] In the present invention, the thickness of any one of the two side PVB layers preferably accounts for 1% to 25% of the total thickness of the PVB layer of the three-layer structure, more preferably 5% to 20%, and even more preferably 10% to 15%.

[0130] In the present invention, the compositions of the two side layers may be the same or different. When they are different, the one with the lower glass transition temperature is recorded as Tg min .

[0131] In the present invention, the intermediate PVB layer is preferably prepared from raw materials comprising a polyvinyl butyral resin having a weight average molecular weight of 100,000 to 200,000 and a plasticizer, more preferably prepared from raw materials comprising a polyvinyl butyral resin having a weight average molecular weight of 120,000 to 180,000 and a plasticizer, and even more preferably prepared from raw materials comprising a polyvinyl butyral resin having a weight average molecular weight of 140,000 to 160,000 and a plasticizer.

[0132] In the present invention, the melt mass flow rate of the polyvinyl butyral resin in the raw material of the intermediate PVB layer is preferably 2.0 to 4.0 g / 10 min, more preferably 2.4 to 3.6 g / 10 min, and even more preferably 2.8 to 3.2 g / 10 min.

[0133] In the present invention, the mass content of the plasticizer in the raw material of the intermediate PVB layer is preferably 10 wt% to 35 wt%, more preferably 15 wt% to 30 wt%, and even more preferably 20 wt% to 25 wt%.

[0134] In the present invention, the plasticizer in the raw material of the intermediate PVB layer preferably includes an aliphatic ester plasticizer.

[0135] In the present invention, the raw materials of the intermediate PVB layer preferably further contain a UV absorber.

[0136] In the present invention, the mass content of the UV absorber in the raw materials of the intermediate PVB layer is preferably 0.1 wt% to 5 wt%, more preferably 1 wt% to 4 wt%, and even more preferably 2 wt% to 3 wt%.

[0137] In the present invention, the UV absorber preferably includes one or more of a salicylate UV absorber, a benzophenone UV absorber, a benzotriazole UV absorber, a triazine UV absorber, a trimethoxybenzoate UV absorber, a p-aminobenzoic acid UV absorber, a phenyl cinnamate UV absorber, a camphor derivative UV absorber, a benzamidine UV absorber and a benzoxazine UV absorber, more preferably a salicylate UV absorber, a benzophenone UV absorber, a benzotriazole UV absorber, a triazine UV absorber, a trimethoxybenzoate UV absorber, a p-aminobenzoic acid UV absorber, a phenyl cinnamate UV absorber, a camphor derivative UV absorber, a benzamidine UV absorber or a benzoxazine UV absorber.

[0138] In the present invention, the raw materials of the intermediate PVB layer preferably further contain an IR absorber.

[0139] In the present invention, the mass of the IR absorber in the raw material of the intermediate PVB layer is preferably 0.1 wt% to 5 wt%, more preferably 1 wt% to 4 wt%, and even more preferably 2 wt% to 3 wt%.

[0140] In the present invention, the IR absorber preferably includes a metal compound and / or a carbide, more preferably a metal compound or a carbide.

[0141] In the present invention, at least one of the two outer surfaces of the multi-layered PVB composite adhesive film is preferably provided with a roll-formed pattern.

[0142] In the present invention, the first glass is preferably transparent glass.

[0143] In the present invention, the second glass is preferably transparent glass.

[0144] In the present invention, the glass is preferably selected from inorganic glass and / or organic glass, more preferably inorganic glass or organic glass.

[0145] In the present invention, the dimming film is preferably selected from one or more of suspended particle dimming film, polymer dispersed liquid crystal dimming film and electrochromic dimming film, more preferably suspended particle dimming film, polymer dispersed liquid crystal dimming film or electrochromic dimming film.

[0146] The present invention is a complete and detailed overall technical solution that better improves the adhesion and mechanical properties of the multi-layer PVB composite film and avoids the performance degradation of the smart glass. The smart glass having the interlayer of the multi-layer PVB composite film can specifically include the following contents:

[0147] A dimming glass, comprising:

[0148] A first transparent glass; a second transparent glass; a dimming film disposed between the first transparent glass and the second transparent glass;

[0149] A first interlayer is provided between the first transparent glass and the dimming film, and / or a second interlayer is provided between the second transparent glass and the dimming film;

[0150] Wherein, the first interlayer and / or the second interlayer is a PVB composite film with a multi-layer structure, and the multi-layer PVB composite film contains at least one layer with a glass transition temperature (Tg) ≤ 45°C, denoted as Tg min , and the glass transition temperature (Tg) of at least one layer is ≥50℃, recorded as Tg max , and Tg max -Tg min ≥15℃. Among them, Tg max Tg max The glass transition temperature Tg of the PVB layer, Tg min Tg min The glass transition temperature Tg of the PVB layer.

[0151] Specifically, the multi-layer PVB composite film has at least one layer of Tg min ≤45°C, comprising a polyvinyl butyral resin with a molecular weight of 100,000 to 200,000 and a plasticizer. The polyvinyl butyral resin has a melt mass flow rate of 5.0 to 10.0 g / 10 minutes and a plasticizer content of 35% wt to 65% wt.

[0152] Specifically, the PVB composite film with a multi-layer structure is a two-layer structure. The upper layer Tg min≤45°C, comprising a polyvinyl butyral resin with a molecular weight of 100,000 to 200,000 and a plasticizer. The polyvinyl butyral resin has a melt mass flow rate of 5.0 to 10.0 g / 10 minutes and a plasticizer content of 35% wt to 65% wt.

[0153] Specifically, the lower layer Tg max ≥50°C, comprising a polyvinyl butyral resin with a molecular weight of 100,000 to 200,000 and a plasticizer, wherein the melt mass flow rate of the polyvinyl butyral resin is 2.0 to 4.0 g / 10 minutes, and the plasticizer content is 10% wt to 35% wt.

[0154] Specifically, the thickness ratio of the upper layer to the lower layer is 1.0 to 2.0.

[0155] Specifically, the PVB composite adhesive film with a multi-layer structure is a three-layer structure. The two side layers of the three-layer PVB composite adhesive film have Tg min ≤45℃. Middle layer Tg max ≥50℃, where the thickness of the two side layers accounts for 1% to 25% of the total thickness respectively.

[0156] Specifically, the thickness ratio of the two side layers is (1.0-2.0):1.

[0157] Specifically, the compositions of the two side layers may be the same or different. When they are different, the one with the lower glass transition temperature is recorded as Tg min .

[0158] Specifically, the two side layers of the three-layer PVB composite film have Tg min ≤45°C, comprising a polyvinyl butyral resin with a molecular weight of 100,000 to 200,000 and a plasticizer. The polyvinyl butyral resin has a melt mass flow rate of 5.0 to 10.0 g / 10 minutes and a plasticizer content of 35% wt to 65% wt.

[0159] Specifically, the middle layer Tg of the three-layer PVB composite film is max ≥50°C, comprising a polyvinyl butyral resin with a molecular weight of 100,000 to 200,000 and a plasticizer, wherein the melt mass flow rate of the polyvinyl butyral resin is 2.0 to 4.0 g / 10 minutes, and the plasticizer content is 10% wt to 35% wt.

[0160] Specifically, the middle layer of the PVB composite adhesive film with a three-layer structure contains a UV absorber with a mass content of 0.1%wt to 5%wt.

[0161] Specifically, the middle layer of the PVB composite adhesive film with a three-layer structure contains an IR absorber with a mass content of 0.1%wt to 5%wt.

[0162] Specifically, the plasticizer contained in both side layers of the three-layer PVB composite film is selected from at least one of phthalates and trimellitic acid esters.

[0163] Specifically, both outer surfaces of the multi-layered PVB composite film have roll-formed patterns.

[0164] Specifically, the dimming film is selected from at least one of a suspended particle dimming film, a polymer dispersed liquid crystal dimming film, and an electrochromic dimming film.

[0165] Specifically, the glass is selected from at least one of inorganic glass and organic glass.

[0166] Specifically, the multi-layered PVB composite film has roll-formed patterns on both outer surfaces. The patterns are essential for the laminated process of making dimming glass, and a reasonable pattern structure facilitates the exhaust stage during the lamination process.

[0167] The multi-layered PVB composite film of the present invention has a low glass transition temperature (Tg) due to the edge layers having a glass transition temperature (Tg) of ≤45°C. Consequently, conventional PVB film surface patterning production processes are not suitable for PVB films with low Tgs. The present invention utilizes a roll-forming patterning production process, enabling large-scale industrial production. Furthermore, the resulting pattern meets the exhaust requirements during the production of switchable glass.

[0168] Specifically, for a multi-layer PVB composite film, for a two-layer structure, the "upper layer" and the "lower layer" are differentiated during the lamination process, so that the "upper layer" faces the PET surface of the dimming film and the "lower layer" faces the glass; for a three-layer structure, the "upper layer" and the "lower layer" are not differentiated during the lamination process, and there is no restriction on whether the "upper layer" or the "lower layer" faces the PET surface of the dimming film or the glass.

[0169] Specifically, the ultraviolet absorber (UV absorber) can be salicylates, benzophenones, benzotriazoles, triazines, trimethoxybenzoates, p-aminobenzoic acids, phenyl cinnamate, camphor derivatives, benzamidines, benzoxazines, etc. Preferably, one or more of Tinuvin-123, UV-3765, UV-328, Tinuvin-384-2, UV-360, UV-327, UV-234, and UV-400 are selected.

[0170] Specifically, the infrared absorber (IR absorber) can be metallized or carbide microparticles, preferably one or more selected from Fe2O3, SiC, SiO2, Si3N4, Al2O3, CaCO3, TiO2, Nb2O5, ZnO, mica, graphite, tungsten bronze, indium tin oxide, antimony tin oxide, and copper sulfide with oxygen defects.

[0171] Specifically, the plasticizer of the upper layer or the side layer can be a benzene polyester, such as phthalates or trimellitic esters, preferably one or more selected from dihexyl phthalate, dioctyl phthalate, diisooctyl phthalate, didecyl phthalate, diisodecyl phthalate, triisodecyl trimellitate, tridecyl trimellitate, trioctyl trimellitate, triisooctyl trimellitate, trihexyl trimellitate, and dioctyl (2-ethylhexyl) 4,5-epoxytetrahydrophthalate.

[0172] Specifically, the plasticizer of the lower layer or the middle layer may be an aliphatic ester, preferably one or more selected from triethylene glycol di-(2-ethylhexanoate), triethylene glycol di-(2-ethylbutyrate), triethylene glycol diheptanoate, tetraethylene glycol diheptanoate, dihexyl adipate, dioctyl adipate, cyclohexyl hexyl adipate, diisononyl adipate, heptylnonyl adipate, and dibutyl sebacate.

[0173] Specifically, there is no special restriction on the types of the first transparent glass and the second transparent glass. They can be transparent glasses used for conventional dimming glasses well known to those skilled in the art. They can be ordinary glasses such as inorganic glass, organic glass, and organic glass such as PC board, PMMA board, etc.; they can also be functional glasses such as UV blocking glass, IR blocking glass, Low-E glass, tempered glass or antibacterial glass, etc.; they can also be selected from colored glasses such as gray glass and brown glass.

[0174] Specifically, the multi-layer PVB composite adhesive film provided by the present invention may also contain antioxidants, light stabilizers, etc., which can provide auxiliary agents for improving the light and heat stability of the PVB composite adhesive film.

[0175] Specifically, the antioxidant is selected from one or more of tetrakis[β-(3,5-di-tert-butylphenyl)propionate]pentaerythritol, tris(2,4-di-tert-butylphenyl)phosphite, β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, ethylene bis(oxyethylene)bis[3-(5-tert-butyl-4-hydroxy-m-tolyl)propionate], triphenyl phosphite and triphenyl phosphate.

[0176] Specifically, the light stabilizer is selected from one or more of bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate, 1-methyl-8-(1,2,2,6,6-pentamethyl-5-piperidinyl) sebacate and 2-(2'-hydroxy-5'-methylphenyl)-benzotriazole.

[0177] Referring to Figure 1, Figure 1 is a schematic structural diagram of the dimming glass provided by the present invention, wherein 1 is transparent glass, 2 is adhesive film, and 3 is dimming film.

[0178] Referring to Figure 2, Figure 2 is a schematic diagram of the structure of a three-layer PVB composite adhesive film provided by the present invention, wherein a is a side layer and b is a middle layer.

[0179] The present invention provides a method for preparing the switchable glass according to any one of the above technical solutions, comprising the following steps:

[0180] 1) Pre-treat the PET surfaces on both sides of the dimming film;

[0181] 2) After stacking the layers according to the structure of the dimming glass, perform a lamination process.

[0182] The present invention first pre-treats the PET surfaces on both outer sides of the dimming film.

[0183] In the present invention, the pretreatment method preferably includes corona treatment and / or plasma treatment, more preferably corona treatment or plasma treatment.

[0184] In the present invention, the pretreatment method preferably includes: firstly coating a solution containing polyvinyl butyral resin on the PET surfaces on both outer sides of the dimming film, and then drying the solvent.

[0185] In the present invention, the pretreatment method preferably includes: first performing corona treatment and / or plasma treatment on the PET surfaces on both sides of the dimming film, then coating the PET surface with a solution containing polyvinyl butyral resin, and then drying the solvent. More preferably, the PET surfaces on both sides of the dimming film are first subjected to corona treatment or plasma treatment, then coating the PET surface with a solution containing polyvinyl butyral resin, and then drying the solvent.

[0186] In the present invention, the solution containing polyvinyl butyral resin preferably includes polyvinyl butyral resin and an organic solvent.

[0187] In the present invention, the mass concentration of the solution containing polyvinyl butyral resin is preferably 5% wt to 15% wt, more preferably 7% wt to 13% wt, and even more preferably 9% wt to 11% wt.

[0188] In the present invention, the weight average molecular weight of the polyvinyl butyral resin is preferably 100,000 to 200,000, more preferably 120,000 to 180,000, and even more preferably 140,000 to 160,000.

[0189] Finally, the present invention stacks the layers according to the structure of the dimming glass and performs a lamination process.

[0190] In the present invention, the temperature of the lamination treatment is preferably 90-120°C, more preferably 95-115°C, and even more preferably 100-110°C.

[0191] The present invention is a complete and detailed overall technical solution that better improves the adhesion and mechanical properties of the multi-layer PVB composite film and avoids the performance degradation of the smart glass. The preparation method of the smart glass having the interlayer of the multi-layer PVB composite film can specifically include the following:

[0192] A method for preparing dimming glass, comprising:

[0193] First pre-treat the PET surface on both sides of the dimming film;

[0194] Then, the layers are stacked according to the structure of the dimming glass and laminated to obtain the dimming glass.

[0195] The temperature of the lamination treatment is 90-120°C.

[0196] Specifically, the lower layer of the two-layer PVB composite film faces the glass.

[0197] Specifically, the surface treatment may be at least one of corona treatment and plasma treatment.

[0198] Specifically, the surface treatment may be to first coat a solution containing polyvinyl butyral resin on the PET surfaces on both outer sides of the dimming film, and then dry the solvent.

[0199] Specifically, the surface treatment may be to first perform at least one of corona treatment and plasma treatment on the PET surfaces on both outer sides of the dimming film, then coat the PET surface with a solution containing polyvinyl butyral resin, and dry the solvent.

[0200] Specifically, the solution containing polyvinyl butyral resin has a molecular weight of 100,000 to 200,000, a mass solution concentration of 5% wt to 15% wt, and an organic solvent.

[0201] Specifically, the lamination method is not particularly limited and can be any conventional lamination method for switchable glass in the art, such as lamination in a laminator, or lamination in an autoclave or laminating box / furnace. In the present invention, the lamination temperature is preferably 90-120°C.

[0202] Experiments have shown that the dimming glass of the present invention adopts a multi-layer PVB composite film and uses it in the production of dimming glass, which solves the problem of dimming glass performance degradation and also meets the adhesion requirements, and has good application prospects.

[0203] The present invention provides the use of the dimming glass described in any one of the above technical solutions or the dimming glass prepared by the preparation method described in any one of the above technical solutions in one or more of automobile window glass, skylight glass and glass curtain wall.

[0204] The present invention provides a method for preparing and applying a multi-layered PVB composite film as an interlayer, a method for preparing the interlayer, and a method for applying the interlayer to the production of a multi-layered PVB composite film. The present invention specifically designs a multi-layered PVB composite film for use in the production of a multi-layered glass, thereby resolving the issue of performance degradation while also meeting adhesion requirements.

[0205] The switchable glass provided by the present invention utilizes a multi-layered PVB composite film. The synergistic effect of the multi-layer structure provides the film with excellent adhesion and mechanical properties. Furthermore, pre-treating the surface of the PET film during manufacture further strengthens the adhesion between the edge layers of the multi-layered PVB composite film and the PET film. This ensures that the switchable glass meets the required adhesion and aging stability, eliminating the problem of performance degradation in the switchable glass. The present invention has significant practical significance and promising application prospects.

[0206] In order to further illustrate the present invention, the following describes in detail a dimming glass provided by the present invention, a preparation method thereof, and an application thereof in combination with embodiments. However, it should be understood that these embodiments are implemented on the premise of the technical solution of the present invention, and detailed implementation methods and specific operating procedures are provided only to further illustrate the features and advantages of the present invention, rather than to limit the claims of the present invention. The scope of protection of the present invention is not limited to the following embodiments.

[0207] Melt flow rate (MFR) test method: According to GB / T 3682.1-2018 sample preparation test, the higher the melt flow rate, the better the high-temperature fluidity of the material.

[0208] Glass transition temperature (Tg) test method: Prepare samples and test according to GB / T 19466.2-2004. The higher the glass transition temperature, the greater the rigidity of the material.

[0209] Test method for the adhesion of switchable glass: Prepare samples and test according to 5.4.6 knock value test in GB / T 32020-2015. The larger the knock value, the stronger the adhesion.

[0210] The dimming performance ΔT of smart glass is measured as follows: When the smart glass is unpowered, the visible light transmittance is recorded as Toff. When the smart glass is connected to a corresponding operating power supply, the visible light transmittance of the smart glass is recorded as Ton. ΔT = Ton - Toff. Different smart glass types have different operating power supplies. For example, suspended particle smart glass can generally be connected to 110V, 60Hz AC, polymer dispersed liquid crystal smart glass can generally be connected to 60V, 60Hz AC, and electro-variable smart glass can generally be connected to 3V DC. The specific power supply should be determined according to the product requirements.

[0211] High temperature stability test method for smart glass: Place 30cm x 30cm smart glass in a 105℃ forced air oven and test the light transmittance after different aging times.

[0212] [Example 1] Two-layer PVB composite film

[0213] The upper plasticizer is dioctyl phthalate, and the glass transition temperature (Tg min ) is 42℃.

[0214] The lower plasticizer is triethylene glycol di-(2-ethylhexanoate), and the glass transition temperature (Tg max ) is 57°C.

[0215] Tg max -Tg min =15°C. Detailed parameters of each layer are shown in Tables 1-1 and 1-2.

[0216] [Example 2] Three-layer PVB composite film

[0217] The plasticizer on both sides is diisodecyl phthalate, and the glass transition temperature (Tg min ) is 20℃.

[0218] The plasticizer of the middle layer is triethylene glycol di-(2-ethyl butyrate), and the glass transition temperature (Tg max ) is 61° C. The middle layer contains Tinuvin-123 as a UV absorber and TiO2 particles as an IR absorber.

[0219] Tg max -Tg min=41°C. Detailed parameters of each layer are shown in Tables 1-1 and 1-2.

[0220] [Example 3] Three-layer PVB composite film

[0221] The plasticizer of both side layers is didecyl phthalate, the glass transition temperature (Tg) of the upper layer is 34℃, and the glass transition temperature (Tg min ) is 20℃.

[0222] The plasticizer of the middle layer is triethylene glycol diheptanoate, and the glass transition temperature (Tg max ) is 72° C. The intermediate layer contains IR absorber Nb2O5 particles.

[0223] Tg max -Tg min = 50°C. Detailed parameters of each layer are shown in Tables 1-1 and 1-2.

[0224] [Example 4] Three-layer PVB composite film

[0225] The plasticizer of both side layers is tridecyl trimellitate, and the glass transition temperature (Tg min ) is 18℃.

[0226] The plasticizer of the middle layer is tetraethylene glycol diheptanoate, and the glass transition temperature (Tg max ) is 65° C. The middle layer contains UV absorber UV-328.

[0227] Tg max -Tg min =47°C. Detailed parameters of each layer are shown in Tables 1-1 and 1-2.

[0228] [Example 5] Three-layer PVB composite film

[0229] The plasticizer of both side layers is trioctyl trimellitate, the glass transition temperature (Tg) of the upper layer is 25℃, and the glass transition temperature (Tg min ) is 15℃.

[0230] The plasticizer of the middle layer is dihexyl adipate, and the glass transition temperature (Tg max ) is 63℃.

[0231] Tg max -Tg min =48°C. Detailed parameters of each layer are shown in Tables 1-1 and 1-2.

[0232] [Example 6] Three-layer PVB composite film

[0233] The plasticizer of both side layers is trihexyl trimellitate, and the glass transition temperature (Tg min ) is 43°C, and the glass transition temperature (Tg) of the lower layer is 45°C.

[0234] The plasticizer of the middle layer is dioctyl adipate and cyclohexyl adipate, with a weight ratio of 1:2. The glass transition temperature (Tg max ) is 78° C. The middle layer contains UV-400 as a UV absorber and tungsten bronze particles as an IR absorber.

[0235] Tg max -Tg min =35°C. Detailed parameters of each layer are shown in Tables 1-1 and 1-2. Tables 1-1 and 1-2 are parameter data tables of the PVB composite adhesive films of the embodiments of the present invention.

[0236] Table 1-1

[0237] Table 1-2

[0238] Note: X indicates non-existence

[0239] [Example 7] Smart Glass

[0240] Two pieces of the two-layer PVB composite film of [Example 1], suspended particle dimming film, and ordinary white glass are used.

[0241] After corona treatment of the PET surfaces on both sides of the dimming film, the layers are stacked according to the structure of the dimming glass, with the upper PVB layer facing the PET surface. Lamination is performed in a laminator under the following conditions: temperature 100°C, vacuum for 10 minutes, gradually increasing the pressure to 450kPa, and delaying for 30 minutes.

[0242] Detailed parameters of the smart glass, such as the knock value and 105°C aging stability time, are shown in Table 2.

[0243] [Example 8] Smart Glass

[0244] Two pieces of the three-layer PVB composite film of [Example 2], a suspended particle dimming film, and gray glass were used.

[0245] After plasma treatment of the PET surfaces on both sides of the dimming film, the layers were stacked according to the structure of the dimming glass and laminated. The lamination conditions were the same as those in Example 7, except that the temperature was 110°C.

[0246] Detailed parameters of the smart glass, such as the knock value and 105°C aging stability time, are shown in Table 2.

[0247] [Example 9] Smart Glass

[0248] Two pieces of the three-layer PVB composite film of [Example 3], a polymer dispersed liquid crystal dimming film, and a PC board were used.

[0249] First, a 5% wt. toluene solution of polyvinyl butyral resin (MW 154,000) was coated on the PET surfaces of both outer sides of the dimming film. After drying the solvent, the layers were laminated according to the structure of the dimming glass. The lamination conditions were the same as in Example 7, except that the temperature was 115°C.

[0250] Detailed parameters of the smart glass, such as the knock value and 105°C aging stability time, are shown in Table 2.

[0251] [Example 10] Smart Glass

[0252] Two pieces of the three-layer PVB composite film of [Example 4], a polymer dispersed liquid crystal dimming film, and Low-E glass were used.

[0253] First, the outer PET surface of the dimming film was coated with a toluene solution containing a 15% wt. polyvinyl butyral resin (MW 101,000). After drying the solvent, the layers were laminated according to the structure of the dimming glass. The lamination conditions were the same as in Example 7, except that the temperature was 90°C.

[0254] Detailed parameters of the smart glass, such as the knock value and 105°C aging stability time, are shown in Table 2.

[0255] [Example 11] Smart Glass

[0256] Two pieces of the three-layer PVB composite film of [Example 5], an electrochromic light-dispersing film, and Low-E glass were used.

[0257] First, a 5% wt. toluene solution of polyvinyl butyral resin (MW 101,000) was coated on the PET surfaces of both outer sides of the dimming film. After drying the solvent, the layers were laminated according to the structure of the dimming glass. The lamination conditions were the same as in Example 7, except that the temperature was 120°C.

[0258] Detailed parameters of the smart glass, such as the knock value and 105°C aging stability time, are shown in Table 2.

[0259] [Example 12] Smart Glass

[0260] Two pieces of the three-layer PVB composite film of [Example 6], an electrochromic light-changing film, and ordinary white glass were used.

[0261] After corona treatment of the PET surfaces on both sides of the dimming film, the PET surfaces were coated with a 5% wt. toluene solution of polyvinyl butyral resin (MW 101,000). After drying the solvent, the layers were laminated according to the structure of the dimming glass. The lamination conditions were the same as in Example 7, except that the temperature was 110°C.

[0262] Detailed parameters of the smart glass, such as the knock value and 105°C aging stability time, are shown in Table 2.

[0263] [Comparative Example 1] Smart Glass

[0264] Same as [Example 8], except that the three-layer PVB composite film in [Example 2] is replaced with a conventional PVB film (RF41 from Eastman), and the PET surface outside the dimming film is not plasma treated before lamination.

[0265] Detailed parameters of the smart glass, such as the knock value and 105°C aging stability time, are shown in Table 2.

[0266] Due to the high hardness and rigidity of conventional PVB laminates, residual stress can cause significant degradation of the dimming performance of switchable glass over long-term use. In this experiment, after aging at 105°C for 216 hours and connecting the glass to 110V, 60Hz AC, most of the center of the glass had lost its dimming performance, as shown in Figure 3.

[0267] FIG3 is a photograph of the switchable glass in Comparative Example 1 of the present invention after aging at 105° C. for 216 hours.

[0268] [Comparative Example 2] Smart Glass

[0269] Same as [Example 8], except that the three-layer PVB composite film in [Example 2] was replaced with a conventional PVB film (RF41 from Eastman).

[0270] Detailed parameters of the smart glass, such as the knock value and 105°C aging stability time, are shown in Table 2.

[0271] [Comparative Example 3] Smart Glass

[0272] Same as [Example 8], except that the PET surface outside the dimming film is not plasma treated before lamination.

[0273] Detailed parameters of the smart glass, such as the knock value and 105°C aging stability time, are shown in Table 2.

[0274] [Comparative Example 4] Smart Glass

[0275] Same as Example 8. The three-layer PVB composite film in Example 2 was replaced with a conventional PVB film (Eastman RF41), and the PET surface outside the dimming film was not plasma treated before lamination. The lamination temperature was 135°C. After lamination, the dimming performance of the dimming glass was severely degraded, with a ΔT of only 11.5%. Testing the aging stability at 105°C was unnecessary.

[0276] Detailed parameters of the smart glass, such as the knock value and 105° C. aging stability time, are shown in Table 2. Table 2 shows the properties of the smart glass prepared in the examples of the present invention and the comparative examples.

[0277] Table 2

[0278] Note: X indicates that the dimming performance is seriously degraded after lamination

[0279] Comparing [Examples 7] to [Examples 12] with [Comparative Example 1] shows that the tapping value of the dimming glass produced by using the multi-layered PVB composite film provided by the present invention and the technical means of pre-treating the PET surfaces on both sides of the dimming film is much greater than that of conventional PVB film. This is because conventional PVB film has a high glass transition temperature and requires a higher lamination temperature to achieve good adhesion between the film and glass, and between the film and PET. Lamination at lower temperatures will result in poor adhesion and low tapping value. At the same time, the aging stability at 105°C has also been greatly improved. [Examples 7] to [Example 12] have an aging stability at 105°C of over 1000 hours, while [Comparative Example 1] only has 216 hours.

[0280] Comparison between [Comparative Example 1] and [Comparative Example 2] shows that the knock value of the dimming glass produced by the technical means of pre-treating the PET surfaces on both sides of the dimming film provided by the present invention is significantly improved.

[0281] Comparison between Example 8 and Comparative Example 3 shows that the technical means of pre-treating the PET surfaces on both sides of the dimming film of the present application can significantly improve the knock value.

[0282] Comparisons of Examples 7 to 12 with Comparative Example 4 show that while the tapping performance of the switchable glass produced using conventional PVB in Comparative Example 4 is comparable to that of the switchable glass produced using the present invention's multi-layered PVB composite film and pre-treated PET surfaces on both sides of the switchable film, conventional PVB has a high glass transition temperature and requires high-temperature lamination to ensure good adhesion between PVB and glass and PVB and PET, resulting in high tapping performance. However, excessively high lamination temperatures significantly degrade the performance of the switchable film. After lamination at 135°C, the switchable performance ΔT of the switchable glass in Comparative Example 4 was only 11.5%.

[0283] In summary, the switchable glass provided by the present invention utilizes a multi-layered PVB composite film. Through the synergistic effect of the multi-layer structure, the multi-layered PVB composite film exhibits excellent adhesion and mechanical properties. Furthermore, pre-treating the surface of the PET film during the manufacture of the switchable glass further enhances the adhesion between the edge layers of the multi-layered PVB composite film and the PET film. This significantly improves the ability of the switchable glass to meet the requirements for adhesion and aging stability.

[0284] The above describes in detail the switchable glass provided by the present invention, wherein the interlayer comprises a multi-layered PVB composite film, and its preparation method and application. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above examples is intended only to facilitate understanding of the methods and core concepts of the present invention, including the best mode, and to enable any person skilled in the art to practice the present invention, including the manufacture and use of any device or system, and the implementation of any combined method. It should be noted that, without departing from the principles of the present invention, a person skilled in the art may make various improvements and modifications to the present invention, and such improvements and modifications fall within the scope of the claims. The scope of patent protection for the present invention is defined by the claims and may include other embodiments that may be conceived by those skilled in the art. Such other embodiments are also intended to be within the scope of the claims if they have structural elements that do not differ from the literal meaning of the claims, or if they include equivalent structural elements that do not differ substantially from the literal meaning of the claims.

Claims

1. A dimming glass, characterized in that, It includes a first glass and a second glass; and a dimming film disposed between the first glass and the second glass; a first interlayer is disposed between the first glass and the dimming film, and / or a second interlayer is disposed between the second glass and the dimming film; The first interlayer is a PVB composite film A with a multi-layer structure; The multi-layer PVB composite film A contains at least one PVB layer with a glass transition temperature Tg ≤ 45°C, denoted as Tg min PVB layer, and at least one PVB layer with a glass transition temperature Tg ≥ 50°C, denoted as Tg max PVB layer; and Tg max -Tg min ≥ 15°C.

2. The dimming glass according to claim 1, wherein The second interlayer is a PVB composite film B with a multi-layer structure; The PVB composite adhesive film B of the multi-layer structure contains at least one PVB layer with a glass transition temperature Tg ≤ 45°C, denoted as Tg min PVB layer, and at least one PVB layer with a glass transition temperature Tg ≥ 50°C, denoted as Tg max PVB layer; and Tg max -Tg min ≥ 15°C.

3. The dimming glass according to claim 1 or 2, characterized in that, The Tg min The PVB layer is obtained by preparing raw materials including polyvinyl butyral resin with a weight average molecular weight of 100,000 to 200,000 and a plasticizer; The Tg min The melt mass flow rate of polyvinyl butyral resin in the raw materials of the PVB layer is 5.0 to 10.0 g / 10 min; The Tg min The mass content of the plasticizer in the raw materials of the PVB layer is 35 wt% to 65 wt%.

4. The dimming glass according to claim 3, characterized in that, The Tg min The plasticizers in the raw materials of the PVB layer include phthalate plasticizers and / or trimellitate plasticizers.

5. The dimming glass according to claim 1 or 2, characterized in that, The Tg max The PVB layer is obtained by preparing raw materials containing polyvinyl butyral resin with a weight average molecular weight of 100,000 to 200,000 and a plasticizer; The Tg max The melt mass flow rate of polyvinyl butyral resin in the raw materials of the PVB layer is 2.0 to 4.0 g / 10 min; The Tg max The mass content of the plasticizer in the raw materials of the PVB layer is 10 wt% to 35 wt%.

6. The dimming glass according to claim 5, wherein, The Tg max The plasticizer in the raw materials of the PVB layer includes aliphatic ester plasticizers.

7. The dimming glass according to claim 1 or 2, characterized in that, The PVB composite film with a multi-layer structure is a PVB composite film with a two-layer structure; The two-layer structure PVB composite film specifically includes an upper PVB layer facing the dimming film and a lower PVB layer facing the glass; The upper PVB layer has a Tg min PVB layer, and the lower PVB layer has a Tg max PVB layer; The thickness ratio of the upper PVB layer to the lower PVB layer is (1.0 - 2.0):

1.

8. The dimming glass according to claim 7, wherein The upper PVB layer is obtained by preparing a raw material containing polyvinyl butyral resin with a weight average molecular weight of 100,000 - 200,000 and a plasticizer; The melt mass flow rate of the polyvinyl butyral resin in the raw material of the upper PVB layer is 5.0 - 10.0 g / 10 min; The mass content of the plasticizer in the raw material of the upper PVB layer is 35wt% - 65wt%; 9. The dimming glass according to claim 8, wherein The plasticizer in the raw material of the upper PVB layer includes phthalate plasticizers and / or trimellitate plasticizers; 10. The dimming glass according to claim 7, characterized in that, The lower PVB layer is obtained by preparing a raw material containing polyvinyl butyral resin with a weight average molecular weight of 100,000 - 200,000 and a plasticizer; The melt mass flow rate of the polyvinyl butyral resin in the raw material of the lower PVB layer is 2.0 - 4.0 g / 10 min; The mass content of the plasticizer in the raw material of the lower PVB layer is 10wt% - 35wt%; 11. The dimming glass according to claim 10, wherein, The plasticizer in the raw material of the lower PVB layer includes aliphatic ester plasticizers; 12. The dimming glass according to claim 10, wherein The raw material of the lower PVB layer further contains a UV absorber; The mass content of the UV absorber in the raw material of the lower PVB layer is 0.1wt% - 5wt%; The UV absorber includes one or more of salicylate UV absorbers, benzophenone UV absorbers, benzotriazole UV absorbers, triazine UV absorbers, trimethoxybenzoate UV absorbers, p-aminobenzoic acid UV absorbers, phenyl cinnamate UV absorbers, camphor derivative UV absorbers, benzamidine UV absorbers, and benzoxazine UV absorbers; 13. The dimming glass according to claim 10, characterized in that, The raw material of the lower PVB layer further contains an IR absorber; The mass content of the IR absorber in the raw material of the lower PVB layer is 0.1wt% - 5wt%; The IR absorber includes metal compounds and / or carbides; 14. The dimming glass according to claim 1 or 2, characterized in that, The PVB composite film with a multi-layer structure is a PVB composite film with a three-layer structure; The three-layer structure PVB composite film specifically includes two side layer PVB layers and an intermediate layer PVB layer; One or both of the two edge PVB layers are Tg min PVB layer; The middle PVB layer has a Tg max PVB layer.

15. The dimming glass according to claim 14, wherein One or both of the two side layer PVB layers are obtained by preparing a raw material containing polyvinyl butyral resin with a weight average molecular weight of 100,000 - 200,000 and a plasticizer; The Tg min The melt mass flow rate of the polyvinyl butyral resin in the raw materials of the PVB layer is 5.0 to 10.0 g / 10 min; The Tg min The mass content of the plasticizer in the raw materials of the PVB layer is 35wt% to 65wt%.

16. The dimming glass according to claim 15, wherein The plasticizer in the raw material of one or both of the two edge layer PVB layers includes phthalate plasticizers and / or trimellitate plasticizers.

17. The dimming glass according to claim 14, characterized in that, In the two edge layer PVB layers, the thickness ratio of the first edge layer PVB layer to the second edge layer PVB layer is (1.0 - 2.0):1; The ratio of the thickness of one of the two edge layer PVB layers to the total thickness of the PVB layer of the three-layer structure is 1% - 25%; 18. The dimming glass according to claim 14, characterized in that, The middle layer PVB layer is obtained by preparing a raw material containing polyvinyl butyral resin with a weight average molecular weight of 100,000 - 200,000 and a plasticizer; The melt mass flow rate of the polyvinyl butyral resin in the raw material of the middle layer PVB layer is 2.0 - 4.0 g / 10 min; The mass content of the plasticizer in the raw material of the middle layer PVB layer is 10wt% - 35wt%; 19. The dimming glass according to claim 18, characterized in that, The plasticizer in the raw material of the middle layer PVB layer includes aliphatic ester plasticizers.

20. The dimming glass according to claim 18, wherein The raw material of the middle layer PVB layer also contains a UV absorber; The mass content of the UV absorber in the raw material of the middle layer PVB layer is 0.1wt% - 5wt%; The UV absorber includes one or more of salicylate UV absorbers, benzophenone UV absorbers, benzotriazole UV absorbers, triazine UV absorbers, trimethoxybenzoate UV absorbers, p-aminobenzoic acid UV absorbers, phenyl cinnamate UV absorbers, camphor derivative UV absorbers, benzamidine UV absorbers, and benzoxazine UV absorbers.

21. The dimming glass according to claim 18, wherein The raw material of the middle layer PVB layer also contains an IR absorber; The mass content of the IR absorber in the raw material of the middle layer PVB layer is 0.1wt% - 5wt%; The IR absorber includes metal compounds and / or carbides.

22. The dimming glass according to claim 1 or 2, characterized in that, On at least one of the two outer surfaces of the PVB composite film with a multi-layer structure, there are roll-formed patterns.

23. The dimming glass according to claim 1 or 2, characterized in that, The first glass is transparent glass; The second glass is transparent glass; The glass is selected from inorganic glass and / or organic glass.

24. The dimming glass according to claim 1 or 2, characterized in that, The light modulating film is selected from one or more of a suspended particle light modulating film, a polymer dispersed liquid crystal light modulating film, and an electrochromic light modulating film.

25. A method for preparing a dimming glass according to any one of claims 1 to 24, characterized in that, It includes the following steps: 1) Pretreat the PET surfaces on both outer sides of the light modulating film; 2) After stacking each layer according to the structure of the light modulating glass, perform lamination treatment.

26. The preparation method according to claim 25, wherein The temperature of the lamination treatment is 90 - 120 °C.

27. The preparation method according to claim 25, characterized in that, The way of the pretreatment includes corona treatment and / or plasma treatment.

28. The preparation method according to claim 25, wherein The way of the pretreatment includes: first coating a solution containing polyvinyl butyral resin on the PET surfaces on both outer sides of the light modulating film, and then drying the solvent.

29. The preparation method according to claim 25, characterized in that, The way of the pretreatment includes: first performing corona treatment and / or plasma treatment on the PET surfaces on both outer sides of the light modulating film, then coating a solution containing polyvinyl butyral resin on the PET surface, and then drying the solvent.

30. The preparation method according to claim 28 or 29, characterized in that, The solution containing polyvinyl butyral resin includes polyvinyl butyral resin and an organic solvent; The mass concentration of the solution containing polyvinyl butyral resin is 5%wt - 15%wt; The weight average molecular weight of the polyvinyl butyral resin is 100,000 - 200,000.

31. Use of the dimming glass according to any one of claims 1 to 24 or the dimming glass prepared by the preparation method according to any one of claims 25 to 30 in one or more of automotive window glass, sunroof glass and glass curtain wall.

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