CN116940539A

CN116940539A - Laminated glass and method for producing laminated glass

Info

Publication number: CN116940539A
Application number: CN202280017942.3A
Authority: CN
Inventors: 横手辰郎; 小森敦; 若林浩和; 定金骏介; 西泽佑介
Original assignee: Asahi Glass Co Ltd
Current assignee: AGC Inc
Priority date: 2021-03-04
Filing date: 2022-03-03
Publication date: 2023-10-24
Also published as: WO2022186338A1; JPWO2022186338A1

Abstract

The reduction in the visibility of HUD images is suppressed, and the degree of chipping off upon impact is reduced. A laminated glass (1) is provided with: the glass comprises a first glass substrate (12), a second glass substrate (14), a reflecting layer (16) arranged between the first glass substrate (12) and the second glass substrate (14), and an adhesive layer (20) arranged between the second glass substrate (14) and the reflecting layer (16) and used for bonding the second glass substrate (14) and the reflecting layer (16). The adhesive layer (20) has a thickness (D5) of 2-25 μm and contains siloxane bonds.

Description

Laminated glass and method for producing laminated glass

Technical Field

The present invention relates to laminated glass and a method for producing laminated glass.

Background

In recent years, introduction of a Head Up Display (HUD) for reflecting an image onto glass of a vehicle or the like and displaying predetermined information in a visual field of a driver is advancing. For example, patent document 1 describes a laminated glass in which a half mirror is provided between an inner surface side glass and an outer surface side glass.

Prior art literature

Patent literature

Patent document 1: japanese patent laid-open publication No. 2019-15783

Disclosure of Invention

Technical problem to be solved by the invention

Such laminated glass for displaying HUD images is required to suppress degradation in the visibility of the displayed HUD images. In addition, laminated glass is also required to reduce the degree of chipping off at the time of impact.

The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a laminated glass and a method for manufacturing a laminated glass, which can reduce the degree of chipping when an impact is applied while suppressing a decline in the visibility of a HUD image.

Means for solving the technical problems

In order to solve the above-described problems and achieve the object, a laminated glass of the present disclosure includes a first glass substrate, a second glass substrate, a reflective layer provided between the first glass substrate and the second glass substrate, and an adhesive layer provided between the second glass substrate and the reflective layer and adhering the second glass substrate and the reflective layer, wherein the adhesive layer has a thickness of 2 μm to 25 μm, and contains siloxane bonds.

In order to solve the above technical problems and achieve the object, a method for manufacturing a laminated glass of the present disclosure includes: a step of forming a siloxane bond-containing adhesive layer having a thickness of 30 [ mu ] m or less using a resin material and a silane compound, and a step of laminating a first glass substrate, a reflective layer, the adhesive layer, and a second glass substrate to form a laminated glass.

Effects of the invention

According to the present invention, the degree of chipping off when an impact is applied can be reduced while suppressing deterioration in the visibility of the HUD image.

Drawings

Fig. 1 is a schematic view of a laminated glass according to the present embodiment.

Fig. 2 is a schematic cross-sectional view of the laminated glass of the present embodiment.

Fig. 3 is an explanatory diagram of the bubble remaining ratio.

Fig. 4 is an explanatory diagram of a method for manufacturing the adhesive layer.

Fig. 5 is a schematic view showing the adhesive layer before lamination.

Fig. 6 is an explanatory diagram of a method for manufacturing a laminated glass.

Detailed Description

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The present invention is not limited to the embodiment, and includes embodiments in which the respective embodiments are combined in the case where there are a plurality of embodiments. Furthermore, the numerical values include rounded ranges.

(laminated glass)

Fig. 1 is a schematic view of a laminated glass according to the present embodiment. The laminated glass 1 of the present embodiment shown in fig. 1 is mounted on a vehicle. The laminated glass 1 is a window member suitable for a windshield of a vehicle, in other words, can be used as a windshield, which is a windshield of a vehicle. The interior (in-vehicle) of a vehicle is, for example, a cabin provided with a driver's seat. However, the use of the laminated glass 1 is not limited to the front window glass of the vehicle, and may be applied to other parts of the vehicle. Hereinafter, the upper edge of the laminated glass 1 is referred to as an upper edge 1a, the lower edge is referred to as a lower edge 1b, one side edge is referred to as a side edge 1c, and the other side edge is referred to as a side edge 1d. The upper edge 1a is an edge located on the upper side in the vertical direction when the laminated glass 1 is mounted on a vehicle. The lower edge 1b is an edge located at a lower side in the vertical direction when the laminated glass 1 is mounted on a vehicle. The side edge 1c is an edge portion located on one side when the laminated glass 1 is mounted on a vehicle. The side edge 1d is an edge portion on the other side when the laminated glass 1 is mounted on a vehicle.

Next, the direction parallel to the surface of the laminated glass 1 is the Y direction (longitudinal direction) from the lower edge 1b toward the upper edge 1a, and the direction from the side edge 1c toward the side edge 1d is the X direction (lateral direction). In this embodiment, the X direction is orthogonal to the Y direction. The direction perpendicular to the surface of the laminated glass 1, that is, the thickness direction of the laminated glass 1 is the Z direction. The Z direction is, for example, a direction from the vehicle outside toward the vehicle inside when the laminated glass 1 is mounted on the vehicle. The X direction and the Y direction are along the surface of the laminated glass 1, but may be directions that contact the surface of the laminated glass 1 at the center point O of the laminated glass 1 when the surface of the laminated glass 1 is curved, for example. The center point O is the center position of the laminated glass 1 when the laminated glass 1 is viewed in the Z direction.

The laminated glass 1 has a light-transmitting region A1 and a light-shielding region A2. The light transmission region A1 is a region occupying the central portion of the laminated glass 1 as viewed in the Z direction, and is a region for ensuring the driver's visual field. The light transmitting region A1 is a region transmitting visible light. The light shielding region A2 is a region formed around the light transmitting region A1 as viewed in the Z direction. The light shielding region A2 is a region that shields visible light. In the light shielding region A2, a far infrared transmission region in which a far infrared camera is provided, a visible light transmission region in which a visible light camera is provided, and the like, which transmit far infrared rays, may be formed.

The light-transmitting region A1 has a HUD region AH formed therein. The HUD area AH is an area that irradiates light from a projector, not shown, and displays HUD images, which are images projected from the projector. The projector is a device that projects an image for HUD onto the laminated glass 1, that is, a projector, for example. The projection device is provided at a position overlapping with the HUD area AH when viewed from the optical axis direction of the projection device. The HUD area AH is formed closer to the X direction side than the center point O, and is formed closer to the side edge portion 1d side than the center point O and is located closer to the lower edge portion 1b side in the example of fig. 1. However, the HUD area AH is arbitrary in position and size, and may be formed closer to the side edge 1c than the center point O, for example. Further, a plurality of HUD areas AH may be formed. The HUD area AH can be said to be a range in which light from a mirror constituting the HUD is irradiated to the windshield when the mirror constituting the HUD is rotated, which is arranged in the vehicle, in the view field of SAE-J1757-2 (2018).

The laminated glass 1 preferably has a radius of curvature in the Y direction (longitudinal direction) of 20000mm or less, and more preferably has a radius of curvature in the Y direction of 4000mm or more. The radius of curvature in the Y direction of the laminated glass 1 is more preferably 6000mm to 20000 mm. The laminated glass 1 preferably has an X-direction (transverse) radius of curvature of 10000mm or less and an X-direction radius of curvature of 1000mm or more. The radius of curvature in the X direction of the laminated glass 1 is more preferably 1500mm to 6000 mm. The Y-direction curvature radius here means a curvature radius of a curve extending in the Y-direction along the surface of the laminated glass 1, and the X-direction curvature radius means a curvature radius of a curve extending in the X-direction along the surface of the laminated glass 1. The radius of curvature of the entire region of the laminated glass 1 is preferably within the above-described range of the radius of curvature. The radius of curvature is obtained by measuring the shape at a predetermined pitch, for example, at a pitch of 20mm, over the entire region of the laminated glass 1 and converting the measured shape into the radius of curvature in the Y direction or the X direction.

The length in the Y direction of the laminated glass 1, that is, the length in the Y direction from the upper edge portion 1a to the lower edge portion 1b is preferably 200mm to 2500mm, more preferably 200mm to 2000mm, and still more preferably 200mm to 1500 mm. The Y-direction length of the laminated glass 1 herein means the Y-direction length at the longest portion. The length in the X direction of the laminated glass 1, that is, the length in the X direction from the side edge portion 1c to the side edge portion 1d is preferably 200mm to 2500mm, more preferably 200mm to 2300mm, and even more preferably 200mm to 2000 mm. The X-direction length of the laminated glass 1 herein means the length in the X-direction at the longest portion.

Fig. 2 is a schematic cross-sectional view of the laminated glass of the present embodiment. Fig. 2 is a sectional view of the laminated glass 1 as seen from the Y direction. As shown in fig. 2, the laminated glass 1 includes a first glass substrate 12, a second glass substrate 14, a reflection layer 16, an intermediate layer 18, an adhesive layer 20, and a light shielding layer 22. In the laminated glass 1, the first glass substrate 12, the intermediate layer 18, the reflection layer 16, the adhesive layer 20, the second glass substrate 14, and the light shielding layer 22 are laminated in this order in the Z direction. The laminated glass 1 displays a HUD image by reflecting light from a projector device on a reflective layer 16 formed in the HUD area AH.

(glass substrate)

The first glass substrate 12 is a glass substrate on the vehicle exterior side. As the first glass substrate 12, for example, soda lime glass, aluminosilicate glass, and organic glass can be used, but is not limited thereto. The thickness D1 of the first glass substrate 12 is preferably 1.8mm to 3.0mm, more preferably 1.9mm to 2.3 mm. By setting the thickness D1 of the first glass substrate 12 within this range, the weight increase can be suppressed and the formability can be reduced while the resistance to flying stones and the like is suitably maintained. The thickness D1 is the length in the Z direction of the first glass substrate 12, and hereinafter, unless otherwise specified, the thickness refers to the Z direction length.

The second glass substrate 14 is a glass substrate on the vehicle interior side. As the second glass substrate 14, for example, soda lime glass, aluminosilicate glass, or organic glass can be used as in the first glass substrate 12, but is not limited thereto. The thickness D2 of the second glass substrate 14 is preferably 0.3mm or more and 2.3mm or less, and more preferably 0.4mm or more and 2.0mm or less. When the thickness of the second glass base 14 is 0.3mm or more, handling at the time of manufacturing, assembling, and the like is easy. By setting the thickness D2 of the second glass substrate 14 within this range, the thickness D1 of the first glass substrate 12 is not increased, and the first glass substrate 12 and the second glass substrate 1 are less likely to be mismatched when stacked after being bent into a curved shape, so that the following performance with respect to the adhesive layer can be suitably maintained.

(reflective layer)

The reflective layer 16 is disposed between the first glass substrate 12 and the second glass substrate 14 in the Z-direction. The reflective layer 16 is a layer that reflects light irradiated from the projection device to the HUD area AH. The reflective layer 16 is transparent to visible light. In the present embodiment, since P-polarized light is irradiated from the projection device, the reflection layer 16 can be said to be a P-polarized light reflection film that reflects the P-polarized light. The reflection layer 16 is formed by laminating a plurality of members such as polymers having different refractive indexes in the Z direction, for example. In a state where the reflection layer 16 is enclosed in the laminated glass 1, the reflection layer 16 preferably has a reflectance of P-polarized light at a brewster angle of 5% or more and 30% or less. The HUD image can be suitably recognized when the reflectance of P-polarized light is 5% or more. The reflective layer 16 is not limited to the P-polarized light reflective film, and may be, for example, a hologram film, a scattering type transparent screen, an antireflection film for HUD, or the like. For example, the reflection layer 16 may have a first layer (for example, a 1/4 wavelength plate) for converting incident P-polarized light into circularly polarized light and a second layer (for example, a cholesteric liquid crystal layer) for selectively reflecting circularly polarized light, and the first layer converts the circularly polarized light reflected by the second layer into P-polarized light and emits the P-polarized light.

The thickness D3 of the reflection layer 16 is preferably 25 μm or more and 200 μm or less, more preferably 40 μm or more and 100 μm or less. The thickness D3 within this range can appropriately reflect light from the projection device and appropriately transmit external light. In the present embodiment, the reflection layer 16 is provided over the entire region of the laminated glass 1 as viewed in the Z direction, but may be provided only in the HUD region AH, for example. That is, the reflection layer 16 may be formed at least in the HUD region AH in the entire region of the laminated glass 1.

(intermediate layer)

An intermediate layer 18 is provided between the first glass substrate 12 and the reflective layer 16 in the Z direction. The intermediate layer 18 is bonded to the first glass substrate 12 on the surface on the vehicle exterior side and to the reflective layer 16 on the surface on the vehicle interior side, thereby bonding the first glass substrate 12 and the reflective layer 16. The intermediate layer 18 is formed of PVB (Poly Vinyl Butyral), i.e., polyvinyl butyral resin. The polyvinyl butyral resin is, for example, a thermoplastic resin obtained by reacting polyvinyl alcohol with n-butyraldehyde.

The thickness D4 of the intermediate layer 18 is thicker than the thickness D5 of the adhesive layer 20 described later. The thickness D4 of the intermediate layer 18 is preferably 0.3mm to 15mm, more preferably 0.3mm to 3mm, and still more preferably 0.7mm to 1 mm. When the thickness of the intermediate layer 18 is within this range, it is possible to suppress an increase in weight and difficulty in handling at the time of manufacture, assembly, and the like while securing safety performance required as a laminated glass.

The intermediate layer 18 is not limited to being formed of a polyvinyl butyral resin, and may be formed of any material such as EVA (Ethylene Vinyl Acetate, ethylene-vinyl acetate copolymer), COP (Cyclo Olefin Polymer, cyclic olefin polymer), or the like. However, when the interlayer 18 is made of the above-listed materials and is bonded to a glass substrate to form a laminated glass, the interlayer 18 can be suitably embossed to suppress the residual bubbles, and the penetration resistance and the adhesiveness as a laminated glass can be ensured. The intermediate layer 18 may have a film having an ultraviolet light absorbing or infrared light absorbing function. The portion of the intermediate layer 18 corresponding to the upper edge portion 1a of the laminated glass 1 may be colored. The interlayer 18 may have three or more layers such as a layer having a sound insulating function and a sound insulating PVB layer interposed therebetween. When the intermediate layer 18 has three or more layers, the thickness of the core layer located at the center in the thickness direction is preferably 70 μm or more and 130 μm or less, more preferably 80 μm or more and 120 μm or less, and still more preferably 90 μm or more and 110 μm or less. The core layer having such a thickness can suppress the decrease in the sound insulation function of the intermediate layer 18.

(adhesive layer)

The adhesive layer 20 is provided between the second glass substrate 14 and the reflective layer 16 in the Z direction. The surface of the adhesive layer 20 on the vehicle exterior side is adhered to the reflective layer 16, and the surface on the vehicle interior side is adhered to the second glass substrate 14, thereby having a function of adhering the reflective layer 16 to the second glass substrate 14.

The adhesive layer 20 is made of resin. In the present embodiment, the adhesive layer 20 is made of polyvinyl butyral resin. However, the adhesive layer 20 is not limited to being formed of polyvinyl butyral resin, and may be formed of any resin material such as EVA and COP. When the adhesive layer 20 is made of the above-listed materials, it is possible to suitably perform embossing to suppress bubble residue and to ensure penetration resistance and adhesion as a laminated glass when the laminated glass is made by bonding the adhesive layer 20 to a glass substrate.

In the present embodiment, the reflective layer 16 is formed over the entire area, and therefore the adhesive layer 20 and the intermediate layer 18 are provided over the entire area with the reflective layer 16 interposed therebetween. However, in the case where the reflection layer 16 is not formed in the entire region, the adhesive layer 20 and the intermediate layer 18 may be integrally bonded to each other in the region where the reflection layer 16 is not formed. In addition, as another configuration, the adhesive layer 20 may be present only in the portion where the reflection layer 16 is present, and in the case where the region where the reflection layer 16 is not present, the intermediate layer 18 and the second glass substrate 14 may be in direct contact with each other in the region where the reflection layer 16 is not present.

The adhesive layer 20 contains a reaction product generated by the reaction of a silane compound (silane coupling agent). That is, the adhesive layer 20 includes a reaction product of a resin (polyvinyl butyral resin in this embodiment) and a silane compound. In the present embodiment, the adhesive layer 20 contains a reaction product of a silane compound in the resin layer. However, the present invention is not limited thereto, and the adhesive layer 20 may be formed as a reaction product layer of a resin layer and a silane compound. In this case, the resin layer of the adhesive layer 20 is located on the side of the reflective layer 16 (vehicle outside), and the reaction product layer of the silane compound is located between the resin layer and the second glass substrate 14.

The silane compound is hydrolyzed to produce a silanol compound having a silanol group (Si-OH group). The silanol compound is bonded to the surface of the second glass substrate 14 through a condensation reaction with a siloxane bond (si—o bond). The functional group contained in the silanol compound is bonded to the resin contained in the adhesive layer 20, the reflective layer 16, and the intermediate layer 18.

The adhesive layer 20 contains siloxane bonds. That is, the adhesive layer 20 is adhered to the surface of the second glass substrate 14 by siloxane bonds. This can suitably improve the adhesion to the second glass substrate 14, and reduce the degree of chipping when the impact is applied. The siloxane bond contained in the adhesive layer 20 corresponds to a reaction product generated by the reaction of the silane compound.

As described above, the adhesive layer 20 preferably includes a functional group that binds to an organic substance such as the resin included in the adhesive layer 20, the reflective layer 16, and the intermediate layer 18. The adhesive layer 20 preferably contains at least one of an amino group and an epoxy group as a functional group, and more preferably contains both an amino group and an epoxy group. The adhesive layer 20 includes at least one of an amino group and an epoxy group as a functional group, so that the adhesion to the resin, the reflective layer 16, the intermediate layer 18, and the like included in the adhesive layer 20 can be suitably improved, and the degree of chipping off can be reduced when an impact is applied. The functional group also corresponds to the reaction product of the silane compound reaction. The adhesive layer 20 contains a silane compound or silanol group, and since it is generally not reacted in all, it is possible to trap unreacted silane compound by using GC-MS or LC-MS, that is, it can be said that silane compound is added.

The adhesive layer 20 preferably does not contain a bond between silicon and methyl. The bonding layer 20 does not contain a bond of silicon and methyl, so that the bonding property can be suitably improved, and the degree of chipping can be reduced when an impact is applied.

The adhesive layer 20 preferably contains Si derived from a silane compound, and the amount of Si detected in the case of quantitatively measuring the adhesive layer 20 is estimated to be about 6 to 10 or less in terms of, for example, mass ratio to Si contained in the silane compound to be added. For example, the content of Si in the adhesive layer 20 is preferably 0.10 mass% or more and 3.2 mass% or less, more preferably 0.2 mass% or more and 1.0 mass% or less, and still more preferably 0.5 mass% or more and 0.6 mass% or less, with respect to the content of all elements contained in the adhesive layer 20. When the content of Si is within this range, siloxane bonds can be sufficiently contained, and adhesion can be suitably improved. The Si content can be determined, for example, as follows: the content of the silane compound was estimated from the element ratio after calculating the element composition ratio by measurement by XPS (X-ray Photoelectron Spectroscopy).

The adhesive layer 20 preferably contains N derived from aminosilane, and the amount of N detected in the case of quantitatively measuring the adhesive layer 20 is estimated to be about 6 to 10 or less in terms of mass ratio, for example, relative to N contained in the added aminosilane. For example, the content of N in the adhesive layer 20 is preferably 0.05 mass% or more and 1.5 mass% or less, more preferably 0.10 mass% or more and 0.50 mass% or less, and still more preferably 0.20 mass% or more and 0.40 mass% or less, with respect to the content of all elements contained in the adhesive layer 20. When the content of N is within this range, the amino group can be sufficiently contained to suitably improve the adhesiveness. The N content was determined by elemental analysis using CHN. The principle of CHN elemental analysis is to burn a weighed organic sample together with oxygen, thermally decompose it, convert carbon, hydrogen, and nitrogen into nitrogen, water, and carbon dioxide, and detect the nitrogen with TCD (thermal conductivity detector).

The adhesive layer 20 preferably contains an epoxy group derived from an epoxy silane, and the amount of the epoxy group detected in the case of quantitatively measuring the adhesive layer 20 is estimated to be about 6 to 10 or less in terms of mass ratio, for example, relative to the epoxy group contained in the added aminosilane. For example, the content of the epoxy group in the adhesive layer 20 is preferably 0.05 mass% or more and 1.5 mass% or less, more preferably 0.10 mass% or more and 0.50 mass% or less, and still more preferably 0.20 mass% or more and 0.40 mass% or less, with respect to the content of all elements contained in the adhesive layer 20. When the content of the epoxy group is within this range, the epoxy group can be sufficiently contained to suitably improve the adhesion.

The thickness D5 of the adhesive layer 20 is 2 μm or more and 25 μm or less, preferably 4 μm or more and 25 μm or less, and more preferably 4 μm or more and 20 μm or less. Within this range, the thickness D5 can suppress the degradation of the HUD image recognition property called orange peel and the degradation of the adhesion property to the second glass substrate 14 and the reflection layer 16. Here, the thickness D5 is a thickness in a state where the adhesive layer 20 is laminated on the laminated glass 1. As will be described later, the adhesive layer 20 may be laminated in a state in which irregularities are formed on the surface, and in this case, the surface of the irregularities is deformed by pressing the reflective layer 16 and the second glass substrate 14 at the time of lamination so that the thickness D5 at the time of lamination falls within the above-described numerical range.

(light-shielding layer)

The light shielding layer 22 is provided on the vehicle interior surface of the second glass substrate 14. The light shielding layer 22 is a layer that shields visible light. As the light shielding layer 22, for example, a ceramic light shielding layer or a light shielding film can be used. As the ceramic light shielding layer, for example, a ceramic layer made of a conventionally known material such as a black ceramic layer can be used. As the light shielding film, for example, a light shielding polyethylene terephthalate (PET) film, a light shielding polyethylene naphthalate (PEN) film, a light shielding polymethyl methacrylate (PMMA) film, and the like can be used. The light shielding layer 22 is not limited to the surface provided on the vehicle interior side of the second glass substrate 14, and may be provided on the surface of the vehicle exterior side of the first glass substrate 12, and may be formed between the first glass substrate 12 and the second glass substrate 14.

The light shielding region A2 is formed by providing the light shielding layer 22 on the laminated glass 1. That is, the light shielding region A2 is a region where the light shielding layer 22 is provided. The light-transmitting region A1 is a region where the glass substrates 12 and 14 are not provided with the light-shielding layer 22.

(bubble survival rate)

Fig. 3 is an explanatory diagram of the bubble remaining ratio. The bubble remaining rate of the laminated glass 1 having the above-described structure is preferably 2% or less, more preferably 1% or less, and still more preferably 0%. When the bubble remaining rate is within this numerical range, deterioration in recognition can be suppressed. It is particularly preferable that the bubble remaining ratio in the HUD area AH is within this numerical range. The bubble remaining rate refers to the remaining degree of bubbles in the laminated glass 1. The bubbles are bubbles existing between the first glass substrate 12 and the second glass substrate 14, and are bubbles that remain in the manufacturing process between the adhesive layer 20 and the second glass substrate 14 without being degassed, for example. The size of the bubble monomer is preferably 2mm or less in diameter. The diameter of the bubble is 2mm or less, which does not easily affect the recognition. The diameter of the bubbles is more preferably 1mm or less. In the case where the bubble is not circular when viewed from the Z direction, the bubble may be treated with the diameter of the circumscribed circle of the bubble.

In the present embodiment, the region where the adhesive layer 20 appears opaque and clouded due to poor adhesion between the adhesive layer 20 and the second glass substrate 14 is regarded as a collection of small bubbles. The areas where the irregularities of the adhesive layer 20 remain and appear to flash are also regarded as a collection of small bubbles. The area of such a region was calculated as the area of the bubble to determine the bubble remaining rate.

The bubble remaining rate will be described in more detail below. As shown in fig. 3, a region 1H is defined as a 100mm square region at an arbitrary position on the surface (in a plan view) of the laminated glass 1 as seen in the Z direction. Light is irradiated onto the laminated glass 1, and the presence of bubbles in the region 1H is observed from the Z direction. For example, the reflection at the bubble may be confirmed by irradiating the laminated glass 1 with a high-intensity lamp, or the light scattering at the bubble may be confirmed by entering light from the end face of the laminated glass 1. The image of the bubble may be confirmed by irradiating light from the opposite side of the laminated glass 1, or the bubble may be confirmed by a laser microscope. For example, in fig. 3, the air bubbles c are present in the first region 1Ha, and the air bubbles are not present in the second region 1Hb which does not overlap with the first region 1 Ha. In this case, the bubble remaining rate in the first region 1Ha is obtained as the ratio of the area of all the bubbles c present in the region 1Ha as seen from the Z direction to the area of the region 1Ha, and the bubble remaining rate in the region 1Hb is zero because there is no bubble c. Since the region 1H is an arbitrary region, the bubble remaining ratio of the entire laminated glass 1 is within the above range. However, the surface 1H is not necessarily required to measure the entire laminated glass 1, and only a square region of 100mm where the bubbles remain the most on the entire laminated glass 1 may be measured as the surface 1H. Further, the determination can be made by using the HUD area AH. For example, the area 1Ha shown in the example of fig. 3 may also coincide with the HUD area AH.

The laminated glass 1 of the present embodiment displays a HUD image by reflecting light from the projector by the reflection layer 16. The present inventors have found that if the adhesive layer 20 between the reflective layer 16 and the second glass substrate 14 is thick, there is a phenomenon that the HUD image recognition called orange peel is lowered. In contrast, in the laminated glass 1 of the present embodiment, the thickness D5 of the adhesive layer 20 is reduced to 25 μm or less, thereby suppressing the orange peel and suppressing the decline of the visibility of the HUD image, and the thickness D5 is 2 μm or more, thereby ensuring the adhesiveness of the adhesive layer 20. Further, since the adhesive layer 20 of the present embodiment contains siloxane bonds, the adhesion to the second glass substrate 14 can be suitably improved, and the degree of chipping can be reduced when an impact is applied.

(method for producing adhesive layer)

Next, a method for manufacturing the laminated glass 1 described above will be described. In the present manufacturing method, the adhesive layer 20 is formed using a resin material that is a resin component material of the adhesive layer 20 and a silane compound (silane coupling agent). More specifically, in the present embodiment, a resin material and a silane compound are added to a solvent to react the silane compound to form the adhesive layer 20. The solvent is, for example, ethanol, but is not limited to ethanol, and may be any liquid. In the case where the adhesive layer 20 is PVB, the resin material is PVB resin before curing. The amount of the resin material to be added is preferably 6% to 15% in terms of mass ratio with respect to the total amount of the solvent, the resin material and the silane compound.

The silane compound reacts to form siloxane bonds contained in the adhesive layer 20. In the present embodiment, as the silane compound, at least one of an aminosilane and an epoxysilane is preferably used, and both of an aminosilane and an epoxysilane are more preferably used. In the present production method, methylsilane is preferably not used as the silane compound. The aminosilane may be at least one of 3-aminopropyl trimethoxysilane, N-2- (aminoethyl) -3-aminopropyl trimethoxysilane, 3-aminopropyl triethoxysilane, N-phenyl-3-aminopropyl trimethoxysilane and 3-triethoxysilyl-N- (1, 3-dimethyl-butenyl) propylamine. The epoxysilane may be at least one of 3-epoxypropoxypropyl trimethoxysilane, 8-epoxypropoxyoctyl trimethoxysilane, 2- (3, 4-epoxycyclohexyl) ethyl trimethoxysilane and 3-epoxypropoxypropyl triethoxysilane.

In the present production method, the amount of the silane compound to be added is preferably 1% to 20% by mass, more preferably 2.5% to 10% by mass, and still more preferably 4% to 6% by mass, based on the amount of the resin material to be added. By setting the addition amount of the silane compound within this range, a siloxane bond can be formed appropriately in the adhesive layer 20, and the adhesion can be improved. The amount of the silane compound to be added here refers to the amount of 1 silane compound to be added when 1 silane compound is added, and refers to the total amount of a plurality of silane compounds to be added when the plurality of silane compounds are added. In the case where both of the aminosilane and the epoxysilane are used as the silane compound, the amount of the aminosilane to be added is preferably 1% to 10% and the amount of the epoxysilane to be added is preferably 1% to 10% by mass relative to the amount of the resin material, more preferably 1% to 5% by mass, and further preferably 1% to 5% by mass, and still more preferably 2% to 3% by mass, and 2% to 3% by mass relative to the amount of the resin material. By setting the addition amount of the aminosilane and the epoxysilane within this range, the adhesion can be improved.

The method of manufacturing the adhesive layer 20 will be described in more detail. Fig. 4 is an explanatory diagram of a method for manufacturing the adhesive layer. In the present manufacturing method, the coating liquid 20A is prepared. The coating liquid 20A contains a resin material, a silane compound, and a solvent. That is, in the present manufacturing method, the coating liquid 20A is prepared by adding the resin material and the silane compound to the solvent. The blending ratio of each component in the coating liquid 20A may be those described above. In the present manufacturing method, a substrate B2 for forming provided on the substrate B1 is prepared as shown in fig. 4. The forming substrate B2 has irregularities (embossments) formed on a surface B2a opposite to the substrate B1. In the present manufacturing method, as shown in step S10 of fig. 4, the coating liquid 20A is applied to the surface B2a of the formation substrate B2. The amount of the coating liquid 20A applied to the formation substrate B2 is set so that the thickness D5 of the adhesive layer 20 when laminated on the laminated glass 1 falls within the above-described numerical range.

After the coating liquid 20A is applied to the surface B2a of the substrate B2 for forming, as shown in step S12 of fig. 4, the liquid component of the coating liquid 20A is removed by drying, and the adhesive layer 20 before being laminated on the laminated glass 1 is formed. The adhesive layer 20 before lamination has irregularities (embossments) formed on the surface 20a on the side contacting the surface B2a of the substrate B2 for formation. The surface 20b of the adhesive layer 20 before lamination, which is opposite to the surface 20a, may not have any irregularities, and may have any shape.

Fig. 5 is a schematic view showing an adhesive layer before lamination. As shown in fig. 5, the thickness D5a is the thickness of the adhesive layer 20 before lamination. The thickness D5a refers to the thickness of the thickest portion of the adhesive layer 20 before lamination, in other words, refers to the length in the Z direction between the portion of the surface 20a protruding to the position farthest from the surface 20b and the portion of the surface 20b protruding to the position farthest from the surface 20 a. In this case, the thickness D5a is preferably 30 μm or less, more preferably 25 μm or less, and still more preferably 10 μm or less. The thickness D5a is preferably 6.2 μm or more, more preferably 6.4 μm or more, and still more preferably 6.6 μm or more. By setting the thickness D5a within this numerical range, the thickness D5 after lamination can be set within the above numerical range, and adhesiveness can be ensured while suppressing deterioration in the visibility of the HUD image.

As shown in fig. 5, the thickness (height) of the portion of the adhesive layer 20 before lamination, on which the irregularities are formed, is referred to as thickness D6a. The thickness D6a refers to a length in the Z direction between a portion of the surface 20a of the adhesive layer 20 before lamination that protrudes to a position farthest from the surface 20b and a portion of the surface 20a of the adhesive layer 20 before lamination that is at a position closest to the surface 20 b. That is, the thickness D6a can be also referred to as the maximum height (maximum height roughness) Rz of the surface 20a defined in JIS B0601. In this case, the thickness D6a is preferably 5 μm or more, more preferably 5.4 μm or more. The thickness D6a is preferably smaller than the thickness D5a of the adhesive layer 20 before lamination. By setting the thickness D6a within this numerical range, irregularities can be formed appropriately, bubbles can be removed appropriately at the time of lamination, and the bubble remaining rate of the laminated glass 1 can be reduced. The thicknesses D5a and D6a can be said to be thicknesses in a state where the pressure higher than the atmospheric pressure is not applied to the adhesive layer 20 before lamination.

The ratio of the thickness D6a to the thickness D5a is referred to as a thickness ratio. In this case, the thickness ratio is preferably less than 0.95, more preferably 0.82 or less, and further preferably 0.63 or less. The thickness ratio is preferably 0.18 or more, more preferably 0.22 or more, and even more preferably 0.27 or more. By setting the thickness ratio within this range, the adhesive layer 20 can be thinned while ensuring the thickness of the non-uneven portion in consideration of deterioration of image clarity, and breakage of the adhesive layer before lamination can be suppressed.

The arithmetic average roughness Ra of the surface 20a of the adhesive layer 20 before lamination, which is prescribed by JIS B0601, is preferably 0.1 μm or more and 10 μm or less, more preferably 0.5 μm or more and 10 μm or less, and still more preferably 0.5 μm or more and 5 μm or less. By setting Ra within this range, irregularities in the entire surface 20a can be formed appropriately, and the bubble remaining rate of the laminated glass 1 can be reduced. That is, the surface 20a of the adhesive layer 20 has an arithmetic average roughness Ra of 0.1 μm or more and 10 μm or less, and can maintain air permeability and suppress the occurrence of irregularities after pressure bonding to the glass substrate.

The shape and size of the irregularities on the surface 20a of the adhesive layer 20 before lamination are the same as those of the irregularities on the surface B2a of the forming substrate B2. Therefore, the thicknesses D5a and D6a of the adhesive layer 20 before lamination, the surface roughness of the surface 20a, and the like described above are determined according to the shape and size of the surface B2a of the formation substrate B2.

In the present embodiment, the adhesive layer 20 before lamination is formed by the method described above. However, the method of forming the adhesive layer 20 is not limited to the above. For example, the coating liquid 20A is not limited to the above-described coating on the forming substrate B2, and the adhesive layer 20 before lamination may not have any irregularities. In the above description, the adhesive layer 20 is formed by mixing the resin material and the silane compound, but the present invention is not limited thereto. For example, the adhesive layer may be formed by forming a layer made of a silane compound and a layer made of a resin material separately.

(method for producing laminated glass)

Next, a method of manufacturing the laminated glass 1 using the adhesive layer 20 manufactured by the above method will be described. Fig. 6 is an explanatory diagram of a method for manufacturing a laminated glass. In the present manufacturing method, the laminated glass 1 is manufactured by laminating the first glass substrate 12, the intermediate layer 18, the reflection layer 16, the adhesive layer 20 manufactured as described above, and the second glass substrate 14. Specifically, as shown in step S20 of fig. 6, the surface 16a of the reflection layer 16 is brought into contact with the surface 20B of the pre-lamination adhesive layer 20 formed on the surface B2a of the formation substrate B2, and the surface 20B is adhered to the surface 16 a. Thereby, the reflection layer 16 and the adhesive layer 20 are bonded and laminated. When bonding the reflection layer 16 and the adhesive layer 20, for example, a pressure bonding process in which the reflection layer 16 and the adhesive layer 20 are heated and pressurized under conditions of a temperature of 80 ℃ or higher, preferably 100 ℃ or higher and a temperature of 150 ℃ or lower, preferably 130 ℃ or lower and a pressure of 0.6MPa or higher, preferably 1.0MPa or higher and a pressure of 3.0MPa or lower, preferably 1.5MPa or lower is adopted.

Next, as shown in step S22 of fig. 6, the formation substrate B2 is removed from the adhesive layer 20 laminated on the reflection layer 16. Thereby, the surface 20a of the adhesive layer 20 on which the irregularities are formed is exposed. The method of removing the formation substrate B2 from the adhesive layer 20 may be any method.

Subsequently, as shown in step S24 of fig. 6, the laminate of the reflection layer 16 and the adhesive layer 20, the first glass substrate 12, the second glass substrate 14, and the intermediate layer 18 are laminated. The intermediate layer 18 has irregularities formed on the surfaces 18a and 18 b. The shape and size of the irregularities of the surfaces 18a and 18b may be arbitrary, and for example, may be the same shape and size as the surface 20a of the adhesive layer 20. In the lamination, the surface 18a of the intermediate layer 18 is brought into contact with the surface 16b of the reflective layer 16 on the opposite side of the surface 16a, and the surface 18a is bonded to the surface 16 b. The pressure and temperature conditions for bonding the surface 18a and the surface 16b may be the same as those for bonding the reflective layer 16 and the adhesive layer 20. Further, the surface 18b of the intermediate layer 18 on the opposite side from the surface 18a is brought into contact with the surface 12a of the vehicle interior side of the first glass substrate 12, and the surface 18b is bonded to the surface 12 a. The surface 14b of the second glass substrate 14 on the opposite side of the vehicle side from the surface 14a is brought into contact with the surface 20a of the adhesive layer 20, and the surface 14b is adhered to the surface 20 a. Thereby, the laminate of the reflection layer 16 and the adhesive layer 20, the first glass substrate 12, the second glass substrate 14, and the intermediate layer 18 are laminated. Specifically, a glass laminate is formed by sandwiching a laminate of the interlayer 18, the reflective layer 16, and the PVB layer 20 between the first glass substrate 12 and the second glass substrate 14. Then, the glass laminate is placed in a rubber bag, and bonded at a temperature of about 70 ℃ to 130 ℃ under a vacuum of-65 kPa to-100 kPa. Further, for example, the pressure-bonding treatment may be performed under heating and pressurizing conditions under a pressure of 0.6MPa to 1.5MPa and a temperature of 100 ℃ to 150 ℃. In step S24, the first glass substrate 12 and the second glass substrate 14 each having a flat plate shape may be subjected to bending, and a laminate of the interlayer 18, the reflection layer 16, and the adhesive layer 20 may be laminated between the first glass substrate 12 and the second glass substrate 14 after the bending. The adhesive layer 20 may be added, and the adhesive layer 20 may be laminated between the second glass substrate 14 and the laminate of the reflective layer 16 and the adhesive layer 20. By stacking a plurality of adhesive layers 20, adjustment of the film thickness becomes easy.

In this way, in step S24, a laminate of the intermediate layer 18, the reflection layer 16, and the adhesive layer 20 is formed, and then the laminate is sandwiched between the first glass substrate 12 and the second glass substrate 14, whereby lamination is performed. However, the order of stacking the components and the conditions of stacking in step S24 are not limited to the above description, and may be any.

By stacking the members in step S24, the laminated glass 1 can be produced as shown in step S26. In the case where the light shielding layer 22 is provided, the light shielding layer 22 may be formed, and other layers may be laminated as necessary.

As described above, in the manufacturing method of the present embodiment, the silane compound is added to form the adhesive layer 20 while thinning the adhesive layer 20 before lamination, so that it is possible to secure adhesion while suppressing degradation of the visibility of the HUD image. Further, since the irregularities are formed on the adhesive layer 20 before lamination, the bubble remaining rate of the laminated glass 1 can be reduced. In addition, the process of forming the irregularities on the adhesive layer 20 as described above is not necessary.

(effects of the present embodiment)

As described above, the laminated glass 1 of the present embodiment includes: the first glass substrate 12, the second glass substrate 14, the reflective layer 16 provided between the first glass substrate 12 and the second glass substrate 14, and the adhesive layer 20 provided between the second glass substrate 14 and the reflective layer 16 for bonding the second glass substrate 14 and the reflective layer 16. The adhesive layer 20 has a thickness D5 of 2 μm to 25 μm, and contains siloxane bonds. In the laminated glass 1 of the present embodiment, the reduction of the thickness D5 of the adhesive layer 20 to 25 μm or less can suppress orange peel and the reduction of the visibility of the HUD image, and the thickness D5 to 2 μm or more can ensure the adhesiveness of the adhesive layer 20. In addition, in the laminated glass 1 of the present embodiment, the adhesion between the adhesive layer 20 and the second glass substrate 14 can be improved by containing siloxane bonds in the adhesive layer 20, and the degree of chipping can be reduced when an impact is applied.

The adhesive layer 20 preferably contains a polyvinyl butyral resin. That is, the adhesive layer 20 preferably contains a polyvinyl butyral resin and contains siloxane bonds. By forming the adhesive layer 20 from a polyvinyl butyral resin, the degree of chipping off when an impact is applied can be reduced more favorably.

In the adhesive layer 20, the content of Si is preferably 0.10 mass% or more and 3.2 mass% or less with respect to the content of all elements contained in the adhesive layer 20. By setting the Si content within this range, the adhesive layer 20 sufficiently contains siloxane bonds, and the degree of chipping off upon impact can be more suitably reduced.

In the adhesive layer 20, the content of N is preferably 0.05 mass% or more and 1.5 mass% or less with respect to the content of all elements contained in the adhesive layer 20. When the content of N is within this range, the amino group is sufficiently contained, and thus the adhesiveness can be suitably improved.

In the adhesive layer 20, the content of the epoxy group is preferably 0.05 mass% or more and 1.5 mass% or less with respect to the content of all elements contained in the adhesive layer 20. When the content of the epoxy group is within this range, the epoxy group is sufficiently contained, and thus the adhesion can be suitably improved.

The laminated glass 1 preferably further includes an intermediate layer 18 made of a polyvinyl butyral resin provided between the first glass substrate 12 and the reflection layer 16. The intermediate layer 18 has a thickness greater than the adhesive layer 20. The laminated glass 1 of the present embodiment can maintain the strength appropriately by providing the intermediate layer 18 thicker than the adhesive layer 20.

In the laminated glass 1, the thickness D5 of the adhesive layer 20 is preferably 4 μm or more and 25 μm or less, and more preferably the thickness D5 of the adhesive layer 20 is 4 μm or more and 20 μm or less. This can suppress degradation of the visibility of the HUD image.

The method for producing a laminated glass according to the present embodiment includes a step of forming a bonding layer 20 containing siloxane bonds and having a thickness D5a of 30 μm or less using a resin material and a silane compound, and a step of forming a laminated glass 1 by sequentially laminating a first glass substrate 12, a reflection layer 16, the bonding layer 20, and a second glass substrate 14. According to the present manufacturing method, by setting the thickness D5a to 30 μm or less, the thickness of the laminated adhesive layer 20 can be reduced, and deterioration in the visibility of the HUD image can be suppressed. In addition, according to the present manufacturing method, since the adhesive layer 20 is formed using the silane compound, the adhesion between the adhesive layer 20 and the second glass substrate 14 can be improved, and the degree of chipping can be reduced when an impact is applied.

Example (example)

The following examples are given. In the examples, laminated glasses were produced by varying the thickness of the adhesive layer after lamination, the material of the silane compound used for forming the adhesive layer, and the content of the silane compound, and evaluated by image clarity and ball drop test. The laminated glass is formed by sequentially laminating a first glass substrate, an intermediate layer, a reflecting layer, an adhesive layer and a second glass substrate. In addition, although the following examples disclose the addition amount of the silane compound for forming the adhesive layer, it is estimated that the adhesive layer formed in each example contains a silanol compound having an addition amount of 6 to 10 inclusive.

Example 1

In example 1, the adhesive layer was formed using PVB as the resin material so that the amount of epoxy silane (KBM 403, made by Xinyue silicone Co., ltd.) added was 2.5% by mass and the amount of amino silane (KBM 903, made by Xinyue silicone Co., ltd.) added was 2.5% by mass, based on the amount of the resin material PVB added. Then, laminated glass was produced so that the thickness of the laminated adhesive layer became 2. Mu.m. In example 1, the thicknesses of the first glass substrate and the second glass substrate were 2.0mm, the interlayer was PVB and 0.76mm, and the reflective layer was 75 μm to 100. Mu.m.

Example 2

In example 2, a laminated glass was produced in the same manner as in example 1, except that the thickness of the adhesive layer after lamination was set to 4. Mu.m.

Example 3

In example 3, a laminated glass was produced in the same manner as in example 1, except that the thickness of the adhesive layer after lamination was 8. Mu.m.

Example 4

In example 4, a laminated glass was produced in the same manner as in example 1, except that the thickness of the adhesive layer after lamination was set to 25. Mu.m.

Example 5

In example 5, a laminated glass was produced in the same manner as in example 1, except that the thickness of the adhesive layer after lamination was set to 30. Mu.m.

Example 6

In example 6, the adhesive layer was formed so that the amount of epoxysilane (KBM 403, made by Xinyue silicone Co., ltd.) added was 5% by mass relative to the amount of resin PVB added. Then, laminated glass was produced so that the thickness of the laminated adhesive layer became 2. Mu.m.

Example 7

In example 7, the adhesive layer was formed so that the amount of epoxysilane (KBM 403, made by Xinyue silicone Co., ltd.) added was 10% by mass relative to the amount of resin PVB added. Then, laminated glass was produced so that the thickness of the laminated adhesive layer became 4. Mu.m.

Example 8

In example 8, the adhesive layer was formed so that the amount of epoxysilane (KBM 903, made by Xinyue silicone Co., ltd.) added was 5% by mass relative to the amount of resin PVB added. Then, laminated glass was produced so that the thickness of the laminated adhesive layer became 4. Mu.m.

Example 9

In example 9, a laminated glass was produced by forming an adhesive layer using PVB as a resin material so that the thickness of the laminated adhesive layer became 4 μm. No silane compound was added to the adhesive layer.

Example 10

In example 10, a laminated glass was produced by forming an adhesive layer using PVB as a resin material so that the thickness of the laminated adhesive layer became 30 μm. No silane compound was added to the adhesive layer.

(definition of image)

The image clarity was evaluated as to whether "longitudinal deformation amount of the line" exceeded 0.017deg when a transverse line of a width of 0.034deg (=2 min) was projected away from the laminated glass 2m, and "longitudinal deformation amount of the line" was marked as o when not exceeding 0.017deg (=1 min) and as x when exceeding 0.017deg (=1 min).

(falling ball test)

In the evaluation of the falling ball test, the impact resistance test according to JIS R3211,3212-2015 was evaluated. The impact resistance test according to JIS R3211,3212-2015 was carried out at both temperatures of 40℃and-20℃and the weight of the chips peeled from the laminated glass after the falling ball test was regarded as "good" as less than 3g at both temperatures of 40℃and-20℃and as "good" as 3g or more and less than 15g at least one temperature of 40℃and-20℃and as "good" as at least 15g at least one temperature of 40℃and-20 ℃.

(evaluation results)

Table 1 shows the conditions and evaluation results of examples 1 to 10. In the evaluation, the evaluation was judged to be excellent or good in the ball drop test and good in the image clarity. And the case where the ball drop test is satisfied is at least one of x and x is the image definition is failed. Examples 1 to 4 and examples 6 to 8 correspond to examples, and examples 5, 9 and 10 correspond to comparative examples. As is clear from examples 1 to 10, the reduction in image sharpness can be suppressed by setting the thickness of the adhesive layer to 2 μm or more and 25 μm or less. It is also known that the addition of a silane compound can form a siloxane bond to improve adhesion and reduce the degree of chipping when an impact is applied. It is also known that the use of epoxysilane and aminosilane as the silane compound can further reduce the degree of chipping.

TABLE 1

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The embodiments of the present invention have been described above, but the embodiments are not limited to the content of the embodiments. The above-described constituent elements include elements which can be easily conceived by those skilled in the art, substantially the same elements, so-called equivalent range elements. The above components may be appropriately combined. Further, various omissions, substitutions, and changes in the constituent elements may be made without departing from the spirit of the embodiments described above.

Symbol description

1. Laminated glass

12. First glass substrate

14. Second glass substrate

16. Reflective layer

18. Intermediate layer

20. Adhesive layer

Claims

1. A laminated glass is provided with:

a first glass substrate,

A second glass substrate,

A reflective layer disposed between the first glass substrate and the second glass substrate, and

an adhesive layer provided between the second glass substrate and the reflective layer for adhering the second glass substrate to the reflective layer,

the adhesive layer has a thickness of 2 μm to 25 μm, and contains siloxane bonds.

2. The laminated glass according to claim 1, wherein the adhesive layer comprises a polyvinyl butyral resin.

3. The laminated glass according to claim 1 or 2, wherein the content of Si in the adhesive layer is 0.10 mass% or more and 3.2 mass% or less with respect to the content of all elements contained in the adhesive layer.

4. The laminated glass according to any one of claims 1 to 3, wherein the content of N in the adhesive layer is 0.05 mass% or more and 1.5 mass% or less with respect to the content of all elements contained in the adhesive layer.

5. The laminated glass according to claim 3 or 4, wherein the content of the epoxy group in the adhesive layer is 0.05 mass% or more and 1.5 mass% or less with respect to the content of all elements contained in the adhesive layer.

6. The laminated glass according to any one of claims 1 to 5, further comprising an intermediate layer formed of a polyvinyl butyral resin provided between the first glass substrate and the reflecting layer,

the thickness of the intermediate layer is greater than the adhesive layer.

7. The laminated glass according to any one of claims 1 to 6, wherein the adhesive layer has a thickness of 4 μm or more and 25 μm or less.

8. The laminated glass according to claim 7, wherein the adhesive layer has a thickness of 4 μm or more and 20 μm or less.

9. A method for manufacturing laminated glass, comprising:

a step of forming a siloxane bond-containing adhesive layer having a thickness of 30 μm or less using a resin material and a silane compound, and

and laminating the first glass substrate, the reflecting layer, the adhesive layer and the second glass substrate to form a laminated glass.