WO2017183701A1

WO2017183701A1 - Vehicle window glass

Info

Publication number: WO2017183701A1
Application number: PCT/JP2017/015944
Authority: WO
Inventors: 神谷　和孝; 大家　和晃; 寺西　豊幸
Original assignee: 日本板硝子株式会社
Priority date: 2016-04-22
Filing date: 2017-04-20
Publication date: 2017-10-26
Also published as: JP6899382B2; JPWO2017183701A1

Abstract

In order to prevent the visibility of a vehicle exterior from a vehicle interior from being impeded even if droplets are formed on a surface due to vapor condensation, a vehicle window glass according to the present invention is provided with: a glass plate 10; and a visibility ensuring film 16 that is formed on a surface on the vehicle interior side, wherein the visibility ensuring film contains a water repellent group and a metal oxide component. The water repellent group is a straight-chain alkyl group that is directly bonded with a metal atom constituting the metal oxide component and that has 3-9 carbons. The glass plate 10 has a top end part 11 in which at least a portion thereof is withdrawn from a window frame of the vehicle when being moved up and down in the vehicle window, and the visibility ensuring film 16 may be formed on a vehicle-interior-side surface 17 of the glass plate so as not to come into contact with the top end part 11.

Description

Vehicle window glass

The present invention relates to a window glass for a vehicle in which even if water droplets are formed on the surface due to condensation of water vapor, it is difficult to visually recognize the outside of the vehicle from the inside of the vehicle.

* Cloudiness caused by condensation of water vapor on the inner surface of the vehicle window glass is a factor that makes it difficult to drive the vehicle. In order to prevent the occurrence of fogging, it has been proposed to form an antifogging film on the vehicle inner surface of the window glass, but there is a limit to the fogging prevention by the antifogging film. For this reason, operation which removes fogging of a window glass by operating a warm air type or energization type defroster is performed suitably. Patent Document 1 discloses a laminated glass having a transparent conductive film therein as a window glass having an energization type defroster.

Japanese Patent Laid-Open No. 2002-20142

The defroster is effective as a defogging means when fogging occurs, but requires energy and time to remove the mist. In spite of such problems, as far as the present inventors know, it is not practical to alleviate the reduction in visibility after fogging by improving the surface of the vehicle window glass itself. There are no examples of reports.

Accordingly, an object of the present invention is to provide a vehicle window glass in which visibility from the inside of the vehicle is hardly hindered even when water droplets are formed on the surface due to condensation of water vapor.

The present invention
Comprising a glass plate, and a visibility ensuring film formed on the inner surface of the glass plate,
The visibility ensuring film includes a water repellent group and a metal oxide component,
The water repellent group provides a vehicle window glass, which is a linear alkyl group having 3 to 9 carbon atoms, which is directly bonded to a metal atom constituting the metal oxide component.

The window glass for a vehicle according to the present invention is suitable for preventing a decrease in visibility from the inside of the vehicle to the outside even if fogging occurs due to condensation of water vapor on the inner surface of the vehicle.

The linear alkyl group having 3 to 9 carbon atoms directly bonded to the metal atom constituting the metal oxide component of the film is suitable for providing a uniform hydrophobic surface, that is, a hydrophobic surface with few hydrophilic spots, It is suitable for suppressing the degree of scattering of light transmitted through the vehicle window glass in a state where water vapor is condensed on the surface of the vehicle window glass.

It is a schematic diagram which shows the state which water vapor | steam condensed on the surface of the film | membrane with a relatively large contact angle of water. It is a schematic diagram which shows the state which water vapor | steam condensed on the surface of the film | membrane with a relatively small contact angle of water. It is a figure for demonstrating an example of the process of apply | coating a coating liquid to a door glass using a nozzle flow coater. It is a figure which shows an example of the locus | trajectory of the position where a coating liquid touches a door glass. It is a figure for demonstrating an example of another process of apply | coating a coating liquid to a door glass using a nozzle flow coater. It is a top view which shows an example of the door glass in which the visibility ensuring film | membrane was formed. It is a top view which shows an example of the door glass connected to the glass raising / lowering apparatus. It is a fragmentary sectional view of the vehicle window for demonstrating the positional relationship of a glass run, a door glass, and a visibility ensuring film | membrane.

Hereinafter, embodiments of the present invention will be described. However, the following description is not intended to limit the present invention to specific embodiments. In this specification, the term “metal oxide component” is intended to include a component composed of only metal atoms and oxygen atoms bonded to each other, as well as a portion in which metal atoms and oxygen atoms are directly bonded. Therefore, for example, the portion represented by MO in the component represented by the formula RMO (R: water repellent group, M: metal atom) constitutes a metal oxide component. Further, the term “metal” in the terms “metal oxide component”, “metal atom”, “metal compound” and the like is used in a sense including boron (B) and silicon (Si) according to common usage.

[Glass plate]
The glass plate may be, for example, a float plate glass that is most commonly used in the fields of vehicles, buildings, and industries. The glass plate need not be colored, but may be colored green, bronze or the like. Moreover, you may process or process into tempered glass, a laminated glass, a multilayer glass, etc. The shape of the main surface may be either a flat surface or a curved surface. The plate thickness is not particularly limited, but is preferably 1 to 5 mm.

When a glass plate is used for a vehicle window glass, a ceramic shielding layer may be formed on the periphery of the vehicle window glass in order to improve the design of the vehicle. The ceramic shielding layer also plays a role of preventing deterioration of the resin material such as an adhesive and a foam material for joining the window glass to the vehicle body due to ultraviolet rays. The ceramic shielding layer is formed by applying a ceramic paste and baking it.

[Visibility film]
The visibility ensuring film is formed on the surface of the glass plate. The surface on which the visibility ensuring film is formed is a surface that faces the inside of the vehicle when installed on a vehicle window. This surface is typically a concave surface of a bent glass sheet. In this case, the visibility ensuring film | membrane is formed in the concave surface of the glass plate which has a convex surface arrange | positioned at the vehicle outer side, and a concave surface arrange | positioned at the vehicle inner side. The visibility ensuring film may be a multilayer film, but is preferably a single layer film. The visibility ensuring film is preferably formed directly on the surface of the glass plate.

The visibility ensuring film contains a water repellent group and a metal oxide component. The visibility ensuring film | membrane may further contain the other functional component as needed, for example, may further contain resin. The resin imparts flexibility to the film and contributes to improvement of hydrophobic uniformity. However, if the content of the resin is too high, the strength of the film may be reduced. Therefore, the visibility ensuring film may not contain any resin in some cases. In particular, the visibility ensuring film preferably does not contain a resin when it is formed on the surface of a glass plate that can slide with other members as the window glass is opened and closed. A typical window glass that slides with another member is a vehicle door glass.

(Water repellent group)
The water repellent group makes the surface of the visibility ensuring film hydrophobic, and makes the surface hard to condense water vapor. However, the water-repellent group contributes to ensuring the straightness of incident light even if water droplets are formed on the surface of the visibility ensuring film, depending on the type. A water-repellent group suitable for ensuring straightness of light is a linear alkyl group having 3 to 9, preferably 4 to 8, particularly 5 to 8, especially 5 to 7 carbon atoms.

As shown in FIGS. 1 and 2, the area where the

water droplets

160 and 161 formed by condensing the same amount of water vapor on the surface of the film 16 cover the film 16 becomes smaller as the contact angle of water on the surface increases. Has a tendency. The smaller the area covered by the

water droplets

160 and 161, the smaller the extent to which light incident on the film 16 is scattered. The visibility ensuring film in which the contact angle of water is increased due to the presence of the water repellent group is less likely to form water droplets on the surface, and the area covered by the water droplets is relatively small even when the water droplets are formed. This is advantageous in maintaining the straightness of transmitted light.

However, the straightness of transmitted light has an influence on the uniformity of hydrophobicity as well as the hydrophobicity indicated by the contact angle of water. This is because, on the surface where the hydrophobicity of the surface of the film 16 is not uniform and hydrophilic spots are scattered, water droplets are formed starting from water vapor adsorbed on the hydrophilic spots. Therefore, it is preferable that the water-repellent group is oriented on the film surface so that the surface of the film 16 becomes uniform hydrophobic. A water repellent group suitable for existing on the film surface in a highly oriented state arranged in the same direction is a linear alkyl group having a certain number of carbon atoms. However, a long straight-chain alkyl group having too many carbon atoms is difficult to achieve high orientation because the straight-chain alkyl group is easily bent in the middle.

If a perfluoroalkyl group is used, stronger hydrophobicity can be realized. However, since the perfluoroalkyl group is a rigid functional group whose crystallinity is remarkably increased particularly when the number of carbon atoms is large, it tends to exist in a polycrystalline orientation on the film surface. For this reason, a locally low hydrophobic portion tends to occur on the film surface. From the viewpoint of ensuring hydrophobic uniformity, a linear alkyl group having the above-described number of carbon atoms is more suitable than a perfluoroalkyl group.

(Hydrolyzable metal compound having water repellent group)
In order to blend a water repellent group into the visibility ensuring film, a metal compound having a water repellent group (water repellent group-containing metal compound), particularly a metal compound having a water repellent group and a hydrolyzable functional group or a halogen atom (Water repellent group-containing hydrolyzable metal compound) or a hydrolyzate thereof may be added to a coating solution for forming a film. In other words, the water repellent group may be derived from a water repellent group-containing hydrolyzable metal compound. The water repellent group-containing hydrolyzable metal compound is preferably a water repellent group-containing hydrolyzable silicon compound represented by the following formula (I).
R _m SiY _4-m (I)
Here, R is a water repellent group, specifically a linear alkyl group having 3 to 9 carbon atoms, Y is a hydrolyzable functional group or a halogen atom, and m is an integer of 1 to 3. is there. The hydrolyzable functional group is, for example, at least one selected from an alkoxyl group, an acetoxy group, an alkenyloxy group, and an amino group, preferably an alkoxy group, particularly an alkoxy group having 1 to 4 carbon atoms. An alkenyloxy group is, for example, an isopropenoxy group. The halogen atom is preferably chlorine. The functional groups exemplified here can also be used as “hydrolyzable functional groups” described below. m is preferably 1 or 2.

The compound represented by formula (I) supplies the component represented by the following formula (II) when hydrolysis and polycondensation have completely proceeded.
R _m SiO _{(4-m) / 2} (II)
Here, R and m are as described above. After hydrolysis and polycondensation, the compound represented by the formula (II) actually forms a network structure in which silicon atoms are bonded to each other through oxygen atoms in the visibility ensuring film.

As described above, the compound represented by the formula (I) is hydrolyzed or partially hydrolyzed, and further, at least partly polycondensed to alternately connect silicon atoms and oxygen atoms, and three-dimensionally. A network structure of spreading siloxane bonds (Si—O—Si) is formed. A water repellent group R is connected to silicon atoms included in the network structure. In other words, the water repellent group R is fixed to the network structure of the siloxane bond through the bond R—Si. This structure is advantageous in uniformly dispersing the water repellent group R in the film. The network structure may contain a silica component supplied from a silicon compound (for example, tetraalkoxysilane, silane coupling agent) other than the water repellent group-containing hydrolyzable silicon compound represented by the formula (I). Forming a visibility ensuring film with a hydrolyzable functional group or a halogen atom-containing silicon compound (water repellent group-free hydrolyzable silicon compound) together with a water repellent group-containing hydrolyzable silicon compound without having a water repellent group When it is added to the coating liquid, a network structure of siloxane bonds including silicon atoms bonded to water repellent groups and silicon atoms not bonded to water repellent groups can be formed. With such a structure, it becomes easy to adjust the water repellent group content and the metal oxide component content in the visibility ensuring film independently of each other.

When a water-repellent group is introduced into the visibility ensuring film using a water-repellent group-containing hydrolyzable silicon compound (see formula (I)), a strong siloxane bond (Si—O—Si) network structure is formed. The formation of this network structure is advantageous not only from the viewpoint of wear resistance but also from the viewpoint of improving hardness, water resistance and the like.

The water repellent group is added to such an extent that the contact angle of water on the surface of the visibility ensuring film is 85 degrees or more, preferably 90 degrees or more, more preferably 95 degrees or more. For the contact angle of water, a value measured by dropping a 4 mg water droplet on the surface of the membrane is adopted. The upper limit of the contact angle of water is not particularly limited, but is, for example, 105 degrees or less, and further 103 degrees or less. It is preferable that the water repellent group is uniformly contained in the visibility ensuring film so that the contact angle of water is in the above range in all regions of the surface of the visibility ensuring film.

A visibility ensuring film | membrane is 1 mass part or more with respect to 100 mass parts of metal oxide components, Preferably it is 3 mass parts or more, More preferably, it is in the range of 4 mass parts or more, and 50 mass parts or less, It is preferable to include a water-repellent group so that it is preferably within a range of 30 parts by mass or less, more preferably 20 parts by mass or less, and in some cases 15 parts by mass or less.

(Metal oxide component)
The visibility ensuring film contains a metal oxide component. The metal oxide component is, for example, an oxide component of at least one element selected from Si, Ti, Zr, Ta, Nb, Nd, La, Ce and Sn, and preferably an Si oxide component (silica component) ).

At least a part of the metal oxide component may be a hydrolyzable metal compound or a metal oxide component derived from the hydrolyzate added to the coating liquid for forming the visibility ensuring film. Here, the hydrolyzable metal compound has a) a metal compound having a water repellent group and a hydrolyzable functional group or a halogen atom (water repellent group-containing hydrolyzable metal compound), and b) a water repellent group. It is at least one selected from a metal compound having a hydrolyzable functional group or a halogen atom (a water-repellent group-free hydrolyzable metal compound). The metal oxide component derived from a) and / or b) is an oxide of metal atoms constituting the hydrolyzable metal compound. The metal oxide component includes a metal oxide component derived from the metal oxide fine particles added to the coating solution for forming the visibility ensuring film, and a hydrolyzable metal compound or a metal oxide component added to the coating solution. And a metal oxide component derived from the hydrolyzate. Again, the hydrolyzable metal compound is at least one selected from a) and b) above. The b), that is, the hydrolyzable metal compound having no water repellent group may contain at least one selected from tetraalkoxysilane and a silane coupling agent. Hereinafter, the metal oxide fine particles and the above b) will be described except for the above-described a).

(Metal oxide fine particles)
The visibility ensuring film may further include metal oxide fine particles as at least a part of the metal oxide component. The metal oxide constituting the metal oxide fine particles is, for example, an oxide of at least one element selected from Si, Ti, Zr, Ta, Nb, Nd, La, Ce and Sn, preferably silica fine particles. is there. Silica fine particles can be introduced into the film, for example, by adding colloidal silica. The metal oxide fine particles are excellent in the action of transmitting the stress applied to the visibility ensuring film to the transparent article supporting the film, and have a high hardness. Therefore, the addition of metal oxide fine particles is advantageous from the viewpoint of improving the wear resistance and scratch resistance of the visibility ensuring film. The metal oxide fine particles can be supplied to the visibility ensuring film by adding the metal oxide fine particles formed in advance to the coating liquid for forming the visibility ensuring film. However, since the metal oxide fine particles can cause a hydrophilic spot on the surface of the film, it is desirable that the metal oxide fine particles should not be added to the film unless there are circumstances to improve the wear resistance and the like. That is, it is preferable to use the visibility ensuring film in a form that does not include metal oxide fine particles unless there is a particular situation where the wear resistance or the like should be emphasized.

If the average particle size of the metal oxide fine particles is too large, the film may become cloudy. If the average particle size is too small, it is difficult to agglomerate and disperse uniformly. From this viewpoint, the preferable average particle diameter of the metal oxide fine particles is 1 to 20 nm, particularly 5 to 20 nm. Here, the average particle diameter of the metal oxide fine particles is described in the state of primary particles. In addition, the average particle diameter of the metal oxide fine particles is determined by measuring the particle diameters of 50 fine particles arbitrarily selected by observation using a scanning electron microscope and adopting the average value. If the content of the metal oxide fine particles is excessive, the film may become cloudy.

(Hydrolyzable metal compound having no water repellent group)
The visibility ensuring film | membrane may contain the metal oxide component derived from the hydrolysable metal compound (water repellent group non-containing hydrolyzable compound) which does not have a water repellent group. A preferred hydrolyzable metal compound containing no water repellent group is a hydrolyzable silicon compound having no water repellent group. The hydrolyzable silicon compound having no water repellent group is, for example, at least one silicon compound selected from silicon alkoxide, chlorosilane, acetoxysilane, alkenyloxysilane and aminosilane (however, having no water repellent group), Silicon alkoxide having no water repellent group is preferred. An example of alkenyloxysilane is isopropenoxysilane.

The hydrolyzable silicon compound having no water repellent group may be a compound represented by the following formula (III).
SiY ₄ (III)
As described above, Y is a hydrolyzable functional group, and is preferably at least one selected from an alkoxyl group, an acetoxy group, an alkenyloxy group, an amino group, and a halogen atom.

The water repellent group-free hydrolyzable metal compound is hydrolyzed or partially hydrolyzed, and further, at least a part thereof is polycondensed to supply a metal oxide component in which a metal atom and an oxygen atom are bonded. This component firmly bonds the metal oxide fine particles and the resin, and can contribute to improvement of the wear resistance, hardness, water resistance, etc. of the visibility ensuring film.

A preferred example of the hydrolyzable silicon compound having no water repellent group is tetraalkoxysilane, more specifically, tetraalkoxysilane having an alkoxy group having 1 to 4 carbon atoms. Tetraalkoxysilanes include, for example, tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetraisopropoxysilane, tetra-n-butoxysilane, tetraisobutoxysilane, tetra-sec-butoxysilane, and tetra-tert- It is at least one selected from butoxysilane.

When the content of the metal oxide (silica) component derived from tetraalkoxysilane is excessive, the hydrophobicity of the visibility ensuring film may be lowered.

(resin)
Resin is an optional component in the visibility ensuring film, but when added, in order to prevent the wear resistance of the film from deteriorating, it exceeds 0 parts by mass and 50 parts by mass or less with respect to 100 parts by mass of the metal oxide component. It is preferable to add in the range. A preferable blending amount of the resin is, for example, 1 part by mass or more, further 5 parts by mass or more, particularly 10 parts by mass or more, 40 parts by mass or less, further 35 parts by mass or less, particularly 30 parts by mass with respect to 100 parts by mass of the metal oxide component. It is below mass parts. Addition of a large amount of resin is desirable to avoid a hydrophilic spot formed on the surface of the film. Although the kind of resin is not specifically limited, In order to prevent formation of a hydrophilic spot, it is preferable to avoid resin with high water absorption. For example, when a polyvinyl butyral resin is used as the resin, the degree of butyralization (degree of acetalization) is preferably 50 mol% or more, particularly 55 mol% or more, and more preferably 60 mol% or more. The upper limit of the degree of butyralization is not particularly limited, but may be 85 mol% or less.

(Other optional ingredients)
You may mix | blend another additive with a visibility ensuring film | membrane. Additives may be glycols, surfactants, leveling agents, ultraviolet absorbers, colorants, antifoaming agents, preservatives, and the like.

(Film thickness)
The thickness of the visibility ensuring film is preferably 3 to 70 nm, preferably 5 to 50 nm, more preferably 7 to 45 m, and particularly 10 to 40 nm.

(Film formation)
The visibility ensuring film can be formed by applying a coating liquid on a transparent article such as a transparent substrate and drying the applied coating liquid. The drying of the working solution may be accompanied by heating. Conventionally known materials and methods may be used as the solvent used for preparing the coating liquid and the coating method.

In the coating liquid coating step, it is preferable to maintain the relative humidity of the atmosphere at less than 40%, more preferably 30% or less. Keeping the relative humidity low can prevent the film from absorbing excessive moisture from the atmosphere. If a large amount of moisture is absorbed from the atmosphere, the water remaining in the membrane matrix may reduce the strength of the membrane.

It is preferable that the drying process of the coating liquid includes an air drying process and a heating drying process with heating. The air drying step is preferably performed by exposing the coating liquid to an atmosphere in which the relative humidity is kept below 40%, and further 30% or less. The air drying process can be performed as a non-heating process, in other words, at room temperature. When a hydrolyzable silicon compound is contained in the coating liquid, in the heat drying step, a dehydration reaction involving a silanol group contained in the hydrolyzate of the silicon compound and a hydroxyl group present on the transparent article proceeds, A matrix structure (Si—O bond network) composed of silicon atoms and oxygen atoms develops.

Appropriate heating temperature in the heating and drying step is 300 ° C. or less, for example, 100 to 200 ° C., and the heating time is 1 minute to 1 hour.

[Specific form as window glass for vehicles]
The vehicle window glass provided with the visibility ensuring film may be used for a fixed window such as a windshield, and is used for an openable window represented by a door glass. Also good. When used for an openable / closable window, the glass plate can be used in a form connected to a glass moving device (a glass lifting device in the case of door glass). Hereinafter, an example of a method for applying a working solution for forming a visibility ensuring film on the inner surface of the door glass used in connection with the glass lifting device will be described.

As shown in FIG. 3, the working solution is applied to the inner surface of a glass plate bent into a door glass shape using, for example, a nozzle flow coater provided with a robot arm and a discharge unit. The coating apparatus called a nozzle flow coater includes a robot arm 7 that moves while holding the glass plate 10 and an injection unit 8 that injects the coating liquid G. The glass plate 10 is held by the robot arm 7 so that a portion held by the robot arm 7 is inclined by an angle d with respect to the vertical direction. The angle d is preferably −3 ° to + 30 ° when the angle at which the vehicle interior main surface 17 faces upward is indicated as positive (+) and the angle at which the vehicle interior main surface 17 faces downward is negative (−). The injection unit 8 includes a nozzle 82 and a base 81 that supports the nozzle 82. In the injection unit 8, the coating liquid G supplied by the tube 84 is injected from the nozzle 82 toward the glass plate 10. The robot arm 7 can hold the glass plate 10 with a suction cup at the tip and move the glass plate 10 relative to the nozzle 82. By controlling the injection of the coating liquid G from the nozzle 82 while relatively moving the nozzle 82 and the glass plate 10, the locus of the position where the coating liquid G contacts the glass plate 10 is controlled. The coating liquid G can be applied to a predetermined region on the vehicle inner main surface 17.

The illustrated glass plate 10 is installed in a door window on the right front side in the traveling direction of a passenger car or the like. As shown in FIG. 4, the left side is shorter than the right side when viewed from the inside of the vehicle. The inner main surface 17 is concave. The locus of the position where the coating liquid G is in contact with the glass plate is shown in FIG.

The injection of the coating liquid G from the nozzle 82 starts from the application start area Ra on the main surface 17 in FIG. 4 and controls the robot arm 7 to move the glass plate 10 downward (arrow U in FIG. 3). Let At this time, the coating liquid G is ejected inward in the surface direction to the extent that the injected coating liquid G does not reach the right end 13. Thereby, the right edge line L2 which is the right edge part of the area | region where the coating liquid G in FIG. 4 is applied appears from the right edge part 13 of the glass plate 10 in the surface direction inner side.

The application position of the coating liquid G moves from the application start area Ra in FIG. 4 in the direction of the arrow S101 and reaches the area Rb, and then the application position moves from the area Rb along the arrow S102 and reaches the area Rc. Then, the glass plate 10 is moved. At this time, the coating liquid G is applied with a gap from the upper end portion 11. The applied coating solution G flows down and reaches the lower end 12. Thereby, the upper edge line L1 of the coating liquid G appears on the lower side in the surface direction from the upper end portion 11 of the glass plate 10, and the coating liquid G is also applied to a region where the lower coating liquid G is not directly injected from the upper edge line L1. The liquid G can be spread. When the application position of the coating liquid G reaches the region Rc, the glass plate 10 is moved so that the application position moves from the region Rc along the arrow S103 and reaches the region Rd. At this time, the injected coating liquid G is injected inward in the surface direction to the extent that the injected coating liquid G does not reach the left end 14. Thereby, the left side edge line L3 which is the left side edge part of the area | region which applies the coating liquid G appears from the left side edge part 14 of the glass plate 10 in the surface direction inner side. In this step, the glass plate 10 is not moved upward, but the glass plate 10 is moved in a direction away from the nozzle 82 and the coating liquid G is applied along the left end portion 14 (FIG. 5). Arrow W).

Since the distance between the nozzle 82 and the glass plate 10 in FIG. 5 increases, the momentum of the coating liquid G immediately before contacting the glass plate is weakened. Therefore, the coating liquid G reaches the left end 14 in FIG. 4 or other main surface (the vehicle outer main surface 18 (see FIG. 8) which is the back surface of the main surface 17 on which the visibility ensuring film 16 is formed). Can be surely prevented from going around.

When the working solution is applied in this way, the visibility ensuring film 16 is formed on a part of the main surface 17 as shown in FIG. 6, but between the upper edge line L1 and the upper end portion 11, the right side A region (film non-formation region) 15 in which the visibility ensuring film 16 is not formed is left between the edge line L2 and the right end 13 and between the left edge line L3 and the left end 14.

A door glass installed in a front door window of a passenger car or the like is attached to a window frame so that the window glass can be moved up and down to open and close the window. At that time, a glass run (sometimes called weatherstrip, molding, etc.) is provided as a member to fill the gap between the window frame and the window glass, and when the window is completely closed, the upper end of the window glass Not only the side end but also the glass run is sandwiched. As shown in FIG. 7, when the window glass is raised and lowered, the upper end portion and the peripheral portion of the side end portion of the glass plate slide with the glass run. The right front door 1 of the automobile in FIG. 7 has an opening 25 surrounded by a frame 2, specifically, an upper frame 21, a lower frame 22, a rear frame 23, and a front frame 24. Along with the glass run 6. The glass run 6 includes an upper frame run 61 in the upper frame 21, a lower frame run 62 in the lower frame 22, a rear frame run 63 in the rear frame 23, and a front frame run 64 in the front frame 24. . The glass plate 10 moves up and down between the height H1 and the height H2 by the glass lifting device 3 to which the lower end is connected.

When the window glass is raised and lowered and the opening and closing operation of the window is repeated, the vicinity of the upper end portion and the vicinity of the side end portion of the window glass slide repeatedly on the glass run. When a film is also applied to the sliding area, the film is damaged by sliding and the surface roughness is increased. The scratches on the coating near the top edge noticeably deteriorate the appearance, and the appearance near the side edge deteriorates and the coefficient of friction with the glass run increases due to the size of the surface roughness. Occasionally, abnormal noise such as chatter noise may occur. In addition, the glass run tends to deteriorate.

As shown in FIG. 8, the film non-formation region 15 in the periphery of the window glass may be set so as to include at least a part of the region in contact with the glass run 6, preferably all of the region in contact with the glass run 6. . According to this preferred embodiment, the visibility ensuring film 16 formed on the main surface 17 by sliding is less likely to be scratched, and thus the above-described problems can be suppressed.

In a preferred form of the invention, the glass plate is at least part of it from the window frame of the window when lowered by the glass lifting device to open the window from a state where it is installed on the window so that the vehicle window is closed. The visibility ensuring film | membrane is formed in the vehicle inner surface of a glass plate so that it may not contact | connect the upper end part of a glass plate (refer FIG. 6). The visibility ensuring film is preferably formed so as to recede from the upper end so as not to contact the glass run 61. More preferably, the visibility ensuring film is formed so as to substantially cover a region where the outside of the vehicle can be seen through from the inside of the vehicle when the vehicle window is closed so that the vehicle window is closed. Here, “substantially covering” means covering 90% or more, more preferably 95% or more. It is also preferable for the glass plate used for the fixed window that the visibility ensuring film substantially covers the region.

It should be noted that a vehicle window glass as a windshield is provided with a region where a visibility ensuring film is not formed, and a sticker that is required to be attached is attached to this region, or for this region to be attached. An indication indicating the presence may be added to the glass plate. According to this embodiment, it is possible to avoid damage to the film during the replacement work.

The following are examples in which various properties of the visibility ensuring film formed on the glass plate were confirmed. First, a method for evaluating the characteristics of the samples produced in the examples will be described.

(1) Appearance The transparency of the sample and the presence or absence of cracks were visually observed and evaluated according to the following criteria.
○: Good Δ: Slight cloudiness is observed.
X: Unevenness, white turbidity, cracks, etc. are observed in the film, and there are practical problems.

(2) Film thickness After the sample was allowed to stand in an environment of room temperature 20 ° C. and relative humidity 50% for 1 hour, the film thickness of the visibility ensuring film was measured using a surface shape measuring instrument α-Step 500 manufactured by KLA Tencor. did.

(3) Contact angle After leaving the sample in an environment of room temperature 20 ° C. and relative humidity 50% for 1 hour, using a contact angle meter (CA-A) manufactured by Kyowa Interface Science Co., Ltd., about 4 μL (= 4 mg) A water droplet was dropped on the surface of the visibility ensuring film, and the contact angle of the water drop on the surface of the visibility ensuring film was measured.

(4) Light straightness during water droplet condensation The sample was left for 1 hour in an environment of room temperature 20 ° C. and relative humidity 30%. On the other hand, warm water whose water temperature is kept at 40 ° C. is stored in a thermostatic water tank, and the sample is placed above the warm water so that the antifogging film is exposed to water vapor, and the entire surface exposed to water vapor is cloudy. Held until the water droplets set. Thereafter, the haze ratio was measured immediately using a haze meter (“HZ-1S” manufactured by Suga Test Instruments Co., Ltd.). The straightness of light during water droplet condensation was evaluated according to the following criteria.
A: The haze ratio was 15% or less.
A: The haze ratio was more than 15% and 35% or less.
X: The haze ratio was more than 35%.

Example 1
0.03% by mass of n-hexyltrimethoxysilane (HTMS, Shin-Etsu Silicone “KBM-3063”), tetraethoxysilane (TEOS, Shin-Etsu Silicone “KBE-04”) 0.3% by mass, purified water 0 A coating solution for forming a visibility-enhancing film was prepared in which 15% by mass, 0.2% by mass of hydrochloric acid as an acid catalyst, and the remainder was an alcohol solvent (“SOLMIX AP-7” manufactured by Nippon Alcohol Industry)

Next, the coating solution was applied by a flow coating method on a washed float plate glass (soda lime silicate glass, thickness 3.1 mm, size 100 × 100 mm) in an environment of room temperature 20 ° C. and relative humidity 30%. After drying for 10 minutes under the same environment, a heat treatment was performed at 120 ° C. for 20 minutes to prepare a sample.

(Example 2)
Except that 0.025% by mass of polyvinyl butyral resin (“S-REC BM-2” manufactured by Sekisui Chemical Co., Ltd., medium polymerization type, butyralization degree 65 mol%) was further added in the same manner as in Example 1, A sample was made.

(Example 3)
A sample was produced in the same manner as in Example 2 except that the amount of n-hexyltrimethoxysilane was 0.01% by mass.

Example 4
Except that 0.035% by mass of n-hexyltrimethoxysilane, 0.7% by mass of tetraethoxysilane, 10% by mass of purified water, and 2% by mass of hydrochloric acid, the same as in Example 1, A sample was made.

(Comparative Example 1)
In the same manner as in Example 1 except that the same amount of methyltrimethoxysilane (MTES, “KBE-13” manufactured by Shin-Etsu Silicone Co., Ltd.) was used instead of 0.03% by mass of n-hexyltrimethoxysilane. A sample was made.

(Comparative Example 2)
In the same manner as in Example 1, except that the same amount of decyltrimethoxysilane (DTMS, “KBM-3103C” manufactured by Shin-Etsu Silicone Co., Ltd.) was used instead of 0.03% by mass of n-hexyltrimethoxysilane. A sample was made.

(Comparative Example 3)
In the same manner as in Example 1 except that the same amount of phenyltrimethoxysilane (PhTMS, “KBM-103” manufactured by Shin-Etsu Silicone Co., Ltd.) was used instead of 0.03% by mass of n-hexyltrimethoxysilane. A sample was made.

(Comparative Example 4)
A sample was prepared in the same manner as in Example 1 except that the same amount of FAS (tridecafluorooctyltrimethoxysilane, manufactured by GELEST) was used instead of 0.03% by mass of n-hexyltrimethoxysilane. Produced. The FAS used is indicated by CF ₃ (CF ₂ ) ₅ (CH ₂ ) ₂ Si (OCH ₃ ) ₃ .

Table 1 shows the components of the visibility ensuring film and the evaluation results of the samples. In Table 1, the mass part of the silica component which is a metal oxide component is set to 100, and the mass part of each component is shown.

The value of the haze ratio for the exposed glass surface on which the visibility ensuring film was not formed was 38.3%. In Comparative Example 4 using FAS, a surface having a large contact angle was obtained with respect to 4 mg of water droplets. On this surface, a large number of fine water droplets were formed in the above-described evaluation (4). The haze rate, which is a measure showing a decrease in straightness, greatly increased. A surface with non-uniform hydrophobicity is not suitable for ensuring visibility when water droplets are formed even if the contact angle of water is large. Further, as can be read from Examples 1 and 2, it was confirmed that the addition of the resin can be a factor for improving the straightness of light by the oriented water-repellent group. However, if priority should be given to ensuring the hardness of the film, it is better to avoid the addition of organic resin.

Claims

A glass plate, and a visibility ensuring film formed on the surface of the glass plate,
The visibility ensuring film includes a water repellent group and a metal oxide component,
The vehicle window glass, wherein the water repellent group is a linear alkyl group having 3 to 9 carbon atoms, which is directly bonded to a metal atom constituting the metal oxide component.
The vehicle window glass according to claim 1, wherein the visibility ensuring film does not contain a resin.
The vehicle window glass according to claim 1, wherein the visibility ensuring film contains a resin in a range of more than 0 parts by mass and 50 parts by mass or less with respect to 100 parts by mass of the metal oxide component.
The vehicle window glass according to any one of claims 1 to 3, wherein the visibility ensuring film is directly formed on a surface of the glass plate.
The vehicle window glass according to any one of claims 1 to 4, wherein the visibility ensuring film is formed on an inner surface of the glass plate.
The glass plate has a convex surface disposed on the vehicle exterior side and a concave surface disposed on the vehicle interior side,
The vehicle window glass according to any one of claims 1 to 5, wherein the visibility ensuring film is formed on the concave surface.
The glass plate has an upper end at least partially separated from the window frame of the window when the glass plate is lowered by a glass elevating device to open the window from a state where the glass plate is installed so that the window of the vehicle is closed. Part
The vehicle window glass according to any one of claims 1 to 6, wherein the visibility ensuring film is formed on an inner surface of the glass plate so as not to contact the upper end portion.
The said visibility ensuring film | membrane is formed so that the area | region which can see through the vehicle exterior from the inside of a vehicle in the state installed in the said window so that the window of a vehicle may close the said glass plate is substantially covered. Vehicle window glass.
The vehicle window according to any one of claims 1 to 8, wherein the visibility ensuring film contains the water-repellent group in a range of 1 to 30 parts by mass with respect to 100 parts by mass of the metal oxide component. Glass.
The vehicle window glass according to any one of claims 1 to 9, wherein the visibility ensuring film has a water contact angle of 85 to 105 degrees measured by dropping a 4 mg water droplet.
The vehicle window glass according to any one of claims 1 to 10, wherein the water repellent group is a linear alkyl group having 5 to 8 carbon atoms.
The vehicle window glass according to any one of claims 1 to 11, wherein the visibility ensuring film has a thickness of 3 to 70 nm.