JP7845115B2 - Vehicle side glass and its manufacturing method - Google Patents

Description

This disclosure relates to vehicle side windows and methods for manufacturing the same.

In applications such as automobiles and other vehicles, glass laminates are known in which a functional film having the function of shielding against ultraviolet and/or infrared rays is formed on the surface of a glass substrate.
Patent Document 1 discloses a liquid composition comprising a hydrolyzable silicon compound and an ultraviolet absorber and/or an infrared absorber, and a glass article having a coating formed using this liquid composition (claims 1, 6, 7, 10).
This document also discloses a method for forming a coating, comprising the steps of applying the above-mentioned liquid composition to the surface of a substrate to form a coating film, and heating the coating film to cure it (Claim 15).

International Publication No. 2015/129563

The functional film should preferably have good functionality in its initial state and maintain good functionality even after long-term use. One aspect of durability is abrasion resistance.
In applications such as vehicle side windows, a glass laminate comprising a glass substrate and a functional film can be raised and lowered to open and close the window. In such applications, it is preferable that the functional film has abrasion resistance that minimizes deterioration of its function even when the surface is repeatedly rubbed.
In the above applications, the surface of the glass laminate, which includes a glass substrate and a functional film, may be cleaned using an alkaline cleaning agent such as sodium bicarbonate. After cleaning with an alkaline cleaning agent, repeated rubbing of the functional film surface may cause scratches.

For the above applications, it is preferable that the functional film has good film-forming properties, suppresses the formation of cracks (also called initial cracks) at the time of film formation, and further possesses abrasion resistance that suppresses the formation of scratches even when the surface is repeatedly rubbed after contact with an alkaline solution.
Patent Document 1 describes the formation of a coating with excellent alkali resistance and abrasion resistance, but the evaluation of alkali resistance and abrasion resistance are independent evaluations, and there is no description of the abrasion resistance of the coating after contact with an alkaline solution.

This disclosure is made in view of the above circumstances and aims to provide a glass laminate for vehicle side windows that has a coating with excellent resistance to initial cracking and abrasion after contact with alkaline liquids.

This disclosure provides the following glass laminates and methods for manufacturing the same.
[1] A glass laminate for a vehicle side window, comprising a glass substrate and a coating formed on one surface of the glass substrate, the coating comprising one or more organic components selected from the group consisting of siloxane bonds, organic groups bonded to Si atoms, and organic compounds, and which is attached to the window opening of a vehicle so as to be openable and closable,
The coating is formed on the surface of the glass substrate in a region including the window opening when the glass laminate is completely closed.
The aforementioned coating is a glass laminate that satisfies the following equations (1A), (2A), and (3A) when the film thickness and Si/C molar ratio are measured at any number of measurement points on a first imaginary line obtained by moving the beltline of the vehicle 2.5 cm upward parallel to the surface of the coating in a plan view with the glass laminate completely closed at the window opening, where the distance between any two adjacent measurement points is 5.0 cm or more.
T≦8.3741×R ^-1.871 ...(1A)
T≧5.0120×R ^-0.290 ...(2A)
R≧0.4...(3A)
(In the formula, T is the film thickness [μm] and R is the Si/C molar ratio [-].)

[2] The glass laminate of [1], wherein the coating satisfies the following formula (4A) when the Si/C molar ratio of the coating is measured at any number of measurement points on the first dashed line where the distance between two adjacent measurement points is 5.0 cm or more, with the glass laminate completely closed at the window opening.
R≦0.8...(4A)

[3] The glass laminate of [1] or [2] satisfies the following formula (1B) when the film thickness and Si/C molar ratio are measured at any number of measurement points on the first dashed line where the distance between two adjacent measurement points is 5.0 cm or more, with the glass laminate completely closed at the window opening.
T≦7.3741×R ^-1.871 ...(1B)

[4] The coating is a glass laminate of any of [1] to [3] such that when the glass laminate is in a state where the window opening is completely closed, the film thickness and Si/C molar ratio of the coating are measured at any number of measurement points on the first dashed line where the distance between two adjacent measurement points is 5.0 cm or more, the following formula (2B) is satisfied.
T≧5.1714×R ^-0.378 ...(2B)

[5] The coating is a glass laminate of any of [1] to [4] such that when the glass laminate is in a state where the window opening is completely closed, the film thickness and Si/C molar ratio of the coating are measured at any number of measurement points on the first dashed line where the distance between two adjacent measurement points is 5.0 cm or more, the following formula (2C) is satisfied.
T≧5.6000×R ^-0.340 ...(2C)

[6] The coating is a glass laminate of any of [1] to [5] such that when the glass laminate is in a state where the window opening is completely closed, the film thickness and Si/C molar ratio of the coating are measured at any number of measurement points on the belt line where the distance between two adjacent measurement points is 5.0 cm or more, the following equations (1A), (2A), and (3A) are satisfied.
T≦8.3741×R ^-1.871 ...(1A)
T≧5.0120×R ^-0.290 ...(2A)
R≧0.4...(3A)

[7] The glass laminate of [6], wherein the coating satisfies the following formula (4A) when the Si/C molar ratio of the coating is measured at any number of measurement points on the beltline where the distance between two adjacent measurement points is 5.0 cm or more, with the glass laminate completely closed at the window opening.
R≦0.8...(4A)

[8] The glass laminate according to any of [1] to [7], wherein, when the glass laminate is in a state where the window opening is completely closed, and in a plan view the belt line is moved 5.0 cm upward along the surface of the coating, the film thickness and Si/C molar ratio of the coating are measured at any number of measurement points where the distance between two adjacent measurement points is 5.0 cm or more, and the following equations (1A), (2A), and (3A) are satisfied.
T≦8.3741×R ^-1.871 ...(1A)
T≧5.0120×R ^-0.290 ...(2A)
R≧0.4...(3A)

[9] The glass laminate of [8] further satisfies the following equation (4A) when the Si/C molar ratio of the coating is measured at any number of measurement points on the second dashed line where the distance between two adjacent measurement points is 5.0 cm or more, with the glass laminate completely closed at the window opening.
R≦0.8...(4A)

[10] A glass laminate according to any one of [1] to [9], wherein the coating is a cured product of a composition comprising one or more hydrolyzable silicon compounds having one or more hydrolyzable groups and which may be partially hydrolyzed and condensed between the same or different types.
[11] The coating comprises one or more functional components selected from the group consisting of ultraviolet shielding agents and infrared shielding agents, and is a glass laminate according to any of [1] to [10].

[12] A step (S1) of preparing a liquid composition containing one or more hydrolyzable silicon compounds having hydrolyzable groups,
Step (S2) is to place the glass substrate on the ground in a substantially horizontal, substantially vertical, or inclined angle between substantially horizontal and substantially vertical, and to apply the liquid composition to one surface of the glass substrate to form a coating film, thereby obtaining a glass substrate with a coating film.
A method for manufacturing a glass laminate according to any one of [1] to [11], comprising the step (S3) of heating the glass substrate with the coating film to cure the coating film.

According to this disclosure, by optimizing the film thickness and Si/C molar ratio in the region near the beltline of the coating, it is possible to provide a glass laminate for vehicle side windows that has good film formation properties, suppresses the formation of cracks (initial cracks) at the time of film formation, and further exhibits excellent abrasion resistance after contact with alkaline liquid.

This is an example of a schematic plan view of a glass laminate according to one embodiment of the present invention. Figure 1 is a schematic cross-sectional view (section along line II-II) of the glass laminate. This graph shows the relationship between the film thickness and Si/C molar ratio at the measurement point on the first dashed line of the coating, and the evaluation results, for the glass laminate obtained in the [Examples] section.

In this specification, unless otherwise specified, the "surface" of a plate-like member such as a glass plate refers to the main surface with a large area, excluding the end face (also called the side face) of the plate-like member.
In this specification, unless otherwise specified, the forward direction of a vehicle is defined as the forward direction, and the reverse direction of a vehicle is defined as the rear direction.
In this specification, unless otherwise specified, the "front and rear,""up and down,""left and right,""vertical and horizontal," and "inside and outside" of a glass laminate refer to the "front and rear,""up and down,""left and right,""vertical and horizontal," and "inside and outside" of the glass laminate when it is fitted into the vehicle (actual usage condition).
In this specification, “approximately horizontal to the ground” means a range of ±10° in the perfectly horizontal direction to the ground, and “approximately vertical to the ground” means a range of ±10° in the perfectly vertical direction to the ground.

Generally, thin film structures are referred to as "films" and "sheets," etc., depending on their thickness. This specification does not clearly distinguish between these terms. Therefore, the term "film" as used herein may sometimes include "sheets."

In a composition containing one or more hydrolyzable silicon compounds, the one or more hydrolyzable silicon compounds may be partially hydrolyzed and condensed with other compounds of the same type or with other compounds of different types.
In this specification, a hydrolysis condensate of one or more hydrolyzable silicon compounds is an oligomer (multimer) produced by hydrolysis of at least a portion of the hydrolyzable groups contained in one or more hydrolyzable silicon compounds, followed by dehydration condensation.

In this specification, "functional group" is a comprehensive term that refers to a reactive group, distinct from a mere substituent.
In this specification, (meth)acrylic is a general term for acrylic and methacrylic, and the same applies to (meth)acrylic acid, (meth)acrylonitrile and (meth)acryloxy, etc.

In this specification, unless otherwise specified, ultraviolet light is light in the wavelength range of 300 to 380 nm, infrared light is light in the wavelength range of 780 to 2500 nm, and visible light is light in the wavelength range of 380 to 780 nm.
In this specification, unless otherwise specified, the "~" indicating a numerical range is used to mean that the numbers before and after it are included as the lower and upper limits, respectively.
Embodiments of the present invention will be described below.

[Glass laminate]
This disclosure relates to a glass laminate for vehicle side windows that is installed in a vehicle window opening so as to be openable and closable.
Referring to the drawings, the structure of a glass laminate according to one embodiment of the present invention will be described. Figure 1 is an example of a schematic plan view of the glass laminate of this embodiment. Figure 2 is a schematic cross-sectional view (section along line II-II) of the glass laminate of this embodiment. For ease of viewing, the scale of each component has been appropriately varied in each figure.

As shown in Figure 2, the glass laminate 1 of this embodiment comprises a glass substrate 10 and a coating 20 formed on one surface 10S of the glass substrate 10. The surface 10S of the glass substrate 10 on which the coating 20 is formed is not particularly limited and can, for example, be the inner surface (also called the interior surface) of the glass substrate 10.

In the example shown in Figure 1, the glass laminate 1 is a side window located next to the driver's or passenger's seat of an automobile. In the illustrated example, the glass substrate 10 has an outer circumference consisting of four sides: an upper edge 11, a lower edge 12, a front side edge 13, and a rear side edge 14, and the lower edge 12 has an uneven surface.
The coating 20 is formed on the surface 10S of the glass substrate 10 in the region including the window opening when the glass laminate 1 is completely closed at the window opening. The coating 20 may be formed over the entire surface 10S of the glass substrate 10, or it may be formed over substantially the entire surface excluding at least a portion of the peripheral edge of the surface 10S of the glass substrate 10 (for example, within 30 mm from the four sides).

In the illustrated example, the coating 20 has an outer circumference consisting of four sides: an upper side 21, a lower side 22, a front side 23, and a rear side 24. For ease of viewing, the portion of the outer circumference of the coating 20 that does not coincide with the outer circumference of the glass substrate 10 is shown with a dashed line. In the illustrated example, the upper side 21 of the coating 20 is located approximately 15 mm inward from the upper side 11 of the glass substrate 10, the front side 23 of the coating 20 coincides with the front side 13 of the glass substrate 10, and the rear side 24 of the coating 20 coincides with the rear side 14 of the glass substrate 10.
The planar shape of the glass substrate 10 and the area where the coating 20 is formed can be appropriately designed according to the form of the vehicle or the like to which it is attached.

The coating 20 contains a siloxane bond (Si-O bond) and one or more organic components selected from the group consisting of organic groups and organic compounds bonded to a Si atom.
The coating 20 can be formed using a coating-forming composition. Preferably, the coating 20 consists of a cured product of a composition containing one or more hydrolyzable silicon compounds (SCs) having one or more hydrolyzable groups and which may be partially hydrolyzed and condensed with other SCs of the same or different types.

The coating 20 can be a functional film that imparts a specific function to a desired area of the glass substrate 10. Examples of functions include selective transmission, absorption, or reflection of light or radio waves in a specific wavelength range; reflection or absorption of heat rays; anti-reflective properties; low reflectivity; low radiation; electrical conductivity; heating properties; water or oil repellency; scratch resistance; stain resistance; antibacterial properties; decorative properties such as coloring; and combinations thereof.
The coating 20 can be a functional film containing, for example, one or more functional components such as an ultraviolet shielding agent and an infrared shielding agent.

In applications such as vehicle side windows, a glass laminate comprising a glass substrate and a coating can be raised and lowered to open and close the window. For details on the side window raising and lowering mechanism, please refer to Japanese Patent Publication No. 2020-172403, etc. In such applications, it is preferable that the coating has abrasion resistance that minimizes deterioration of function even when the surface is repeatedly rubbed.
In the above applications, the surface of the glass laminate, including the glass substrate and the coating, may be cleaned using an alkaline cleaning agent such as baking soda. After cleaning with an alkaline cleaning agent, repeated rubbing of the coating surface may cause scratches.
For the above applications, it is preferable that the coating has good film-forming properties, suppresses the formation of cracks (initial cracks) at the time of film formation, and also has abrasion resistance that suppresses the formation of scratches even when the surface is repeatedly rubbed after contact with an alkaline solution.

The inventors of this invention focused on the fact that, in applications on vehicle side windows, wear is significant in the area of the coating near the beltline due to opening and closing the window.
Vehicle window frames are fitted with sealing material to seal any gaps and prevent rain and wind from entering the vehicle.
In this specification, unless otherwise specified, “beltline” refers to the upper edge of a sealing material installed along the lower edge of a vehicle window opening.

Possible methods to improve the wear resistance of the coating include (i) increasing the thickness of the coating to alleviate shear stress, and (ii) increasing the hardness of the coating by increasing the Si/C molar ratio. However, both methods increase the internal stress of the coating, which may reduce its resistance to initial cracking. Furthermore, increasing the Si/C molar ratio may reduce wear resistance after contact with alkaline solutions.

Therefore, the inventors investigated how to optimize the film thickness and Si/C molar ratio in the region near the belt line of the coating.
The inventors measured the film thickness and Si/C molar ratio of each glass laminate obtained in the [Examples] section at a plurality of arbitrary measurement points on a first imaginary line obtained by shifting the beltline 2.5 cm upward along the surface of the film in a plan view.
Furthermore, for several glass laminate coatings obtained in the [Examples] section, similar measurements were also performed at multiple arbitrary measurement points on the beltline, and at multiple arbitrary measurement points on a second imaginary line obtained by shifting the beltline 5.0 cm upward along the surface of the coating.

In this specification, unless otherwise specified, “a certain area or point on the coating” refers to a certain area or point on the coating when the glass laminate is completely closed at the window opening.
For example, "region near the beltline of the coating" refers to the region near the beltline of the coating when the glass laminate is completely closed at the window opening. "A certain measurement point on the beltline of the coating" refers to a certain measurement point on the beltline of the coating when the glass laminate is completely closed at the window opening. "A certain measurement point on the first or second imaginary line of the coating" refers to a certain measurement point on the first or second imaginary line of the coating when the glass laminate is completely closed at the window opening.

In Figure 1, the dashed line indicated by the symbol BL schematically represents the beltline, the dashed line indicated by the symbol IL1 represents the first imaginary line, and the dashed line indicated by the symbol IL2 represents the second imaginary line. In this figure, these lines are shown as straight lines, but the beltline BL is usually a curve, and the first imaginary line IL1 and the second imaginary line IL2, which are obtained by shifting the beltline upwards in parallel, are also usually curves.
In the glass laminate 1, the "region near the beltline" specifically refers to the first beltline vicinity region NBL1 from the beltline BL to the first virtual line IL1, the second beltline vicinity region NBL2 from the first virtual line IL1 to the second virtual line IL2, and the third beltline vicinity region NBL3 from the beltline BL to the second virtual line IL2, etc.

The inventors evaluated the initial crack resistance and abrasion resistance after contact with alkaline solution for each glass laminate coating obtained in the [Examples] section, and obtained a graph showing the relationship between the coating thickness and Si/C molar ratio at measurement points on the first dashed line of the coating and the evaluation results. This graph is shown in Figure 3. From this graph, the inventors succeeded in optimizing the coating thickness and Si/C molar ratio so that both the evaluation results for initial crack resistance and abrasion resistance after contact with alkaline solution were good, thus completing the present invention.
In this specification, the film thickness [μm] is denoted by the symbol T, and the Si/C molar ratio [-] is denoted by the symbol R. In this specification, all formulas defining the preferred ranges of T and R are empirical formulas obtained by the inventors through numerous experiments.

In the glass laminate of this disclosure, when the film thickness (T [μm]) and Si/C molar ratio (R [-]) are measured at any number of measurement points on a first imaginary line obtained by shifting the vehicle's beltline 2.5 cm upward along the surface of the film in a plan view, where the distance between two adjacent measurement points is 5.0 cm or more, the following equations (1A), (2A), and (3A) are satisfied, and preferably, the following equations (1A-b), (2A-b), and (3A-b) are satisfied.

T≦8.3741×R ^-1.871 ...(1A)
T≧5.0120×R ^-0.290 ...(2A)
R≧0.4...(3A)

T<8.3741×R ^-1.871 ...(1A-b)
T>5.0120×R ^-0.290 ...(2A-b)
R>0.4...(3A-b)

In the glass laminate of this disclosure, the number of measurement points on the same line is two or more, preferably three or more, and more preferably five or more.

The graph in Figure 3 shows the curves represented by the following equations (1A-L), (2A-L), and (3A-L), corresponding to equations (1A), (2A), and (3A), respectively.
T=8.3741×R ^-1.871 ...(1A-L)
T=5.0120×R ^-0.290 ...(2A-L)
R=0.4...(3A-L)

It is also preferable that the coating satisfies equations (1A), (2A), and (3A) at any multiple measurement points on the beltline where the distance between two adjacent measurement points is 5.0 cm or more.
In this case, the coating exhibits excellent resistance to initial cracking and abrasion after contact with alkaline liquid in the first beltline vicinity region NBL1, from the beltline to the first imaginary line.

It is also preferable that the coating satisfies equations (1A), (2A), and (3A) at any multiple measurement points where the distance between two adjacent measurement points is 5.0 cm or more, on a second imaginary line obtained by shifting the beltline 5.0 cm upward along the surface of the coating in a plan view.
In this case, the coating will exhibit excellent resistance to initial cracking and abrasion after contact with alkaline liquid in the region NBL2 near the second beltline from the first virtual line to the second virtual line, or in the region NBL3 near the third beltline from the beltline to the second virtual line.

If the film thickness in the region near the beltline is too high, there is a risk of initial crack formation. If the film thickness (T) at the measurement point on the first imaginary line of the film is 8.3741 × R ^{- 1.871} or less, the film in the region near the beltline is not too thick, and the initial crack resistance is good.
If the film thickness (T) at the measurement point on the first imaginary line of the coating is 5.0120 × R ^{- 0.290} or greater, the abrasion resistance of the coating in the region near the beltline after contact with an alkaline solution will be good.
If the Si/C molar ratio (R) at the measurement point on the first imaginary line of the coating is 0.4 or higher, the hardness of the coating in the region near the belt line is sufficiently high, and the wear resistance after contact with alkaline solution is good.
If the measurement points on the first imaginary line of the coating satisfy equations (1A), (2A), and (3A), the coating can have initial crack resistance that suppresses the formation of cracks (initial cracks) at the time of film formation in the region near the belt line, and further, it can have abrasion resistance that suppresses the formation of scratches even if the surface is repeatedly rubbed after contact with an alkaline solution.

As shown in Figure 3, as the Si/C molar ratio (R) increases, the range between the curve represented by equation (1A-L) and the curve represented by equation (2A-L) narrows, and the range of film thickness (T) in which the desired effect can be obtained tends to narrow.
In Figure 3, the Si/C molar ratio (R) at the intersection of the curve represented by equation (1A-L) and the curve represented by equation (2A-L) represents the upper limit of the Si/C molar ratio (R). The upper limit of the Si/C molar ratio (R) is 1.3835.
If the range of film thickness (T) required to achieve the desired effect is narrow, it becomes necessary to strictly control the film thickness (T) within that narrow range, which may lead to a higher defect rate in the manufacturing process.

When measuring the film thickness (T [μm]) and Si/C molar ratio (R [-]) at any number of measurement points on the first dashed line where the distance between two adjacent measurement points is 5.0 cm or more, it is preferable that the Si/C molar ratio (R) is 1.2 or less, 1.0 or less, or 0.9 or less.
Preferably, the coating has a Si/C molar ratio (R) of 1.2 or less, 1.0 or less, or 0.9 or less at any multiple measurement points on the beltline where the distance between two adjacent measurement points is 5.0 cm or more.
Preferably, the coating has a Si/C molar ratio (R) of 1.2 or less, 1.0 or less, or 0.9 or less at any multiple measurement points on the second imaginary line where the distance between two adjacent measurement points is 5.0 cm or more.

It is more preferable that the coating satisfies the following formula (4A) when the Si/C molar ratio (R[-]) of the coating is measured at any number of measurement points on the first imaginary line where the distance between two adjacent measurement points is 5.0 cm or more.
R≦0.8...(4A)
The graph shown in Figure 3 shows a straight line represented by the following equation (4A-L), which corresponds to equation (4A).
R=0.8...(4A-L)

The Si/C molar ratio (R) at the measurement point on the first imaginary line of the coating is more preferably 0.7 or less, and particularly preferably 0.6 or less.
It is more preferable that the coating satisfies formula (4A), R ≤ 0.7, or R ≤ 0.6 at any multiple measurement points on the beltline where the distance between two adjacent measurement points is 5.0 cm or more.
It is more preferable that the coating satisfies equation (4A), R ≤ 0.7, or R ≤ 0.6 at any multiple measurement points on the second imaginary line where the distance between two adjacent measurement points is 5.0 cm or more.
If the Si/C molar ratio (R) at the measurement point on the first imaginary line of the coating is 0.8 or less, 0.7 or less, or 0.6 or less, the range of film thickness (T) in which the desired effect can be obtained is relatively wide, eliminating the need for strict control of the film thickness (T) and improving the yield rate of good products in the manufacturing process.

Preferably, when the film thickness (T [μm]) and Si/C molar ratio (R [-]) are measured at any number of measurement points on the first imaginary line where the distance between two adjacent measurement points is 5.0 cm or more, the film satisfies the following formula (1B).
T≦7.3741×R ^-1.871 ...(1B)
The graph shown in Figure 3 shows the curve represented by the following equation (1B-L), which corresponds to equation (1B).
T=7.3741×R ^-1.871 ...(1B-L)
If the measurement point on the first imaginary line of the coating satisfies the above requirements, the coating will exhibit superior initial crack resistance and abrasion resistance after contact with alkaline solution in the region near the beltline.

It is preferable that the coating satisfies formula (1B) at any multiple measurement points on the beltline where the distance between two adjacent measurement points is 5.0 cm or more.
Preferably, the coating satisfies equation (1B) at any multiple measurement points on the second imaginary line where the distance between two adjacent measurement points is 5.0 cm or more.

When the film thickness (T [μm]) and Si/C molar ratio (R [-]) are measured at any number of measurement points on the first imaginary line where the distance between two adjacent measurement points is 5.0 cm or more, it is preferable that the following formula (2B) (preferably, formula (2B-b)) is satisfied, and more preferably, that formula (2C) (preferably, formula (2C-b)) is satisfied.

T≧5.1714×R ^-0.378 ...(2B)
T≧5.6000×R ^-0.340 ...(2C)

T>5.1714×R ^-0.378 ...(2B-b)
T>5.6000×R ^-0.340 ...(2C-b)

The graph in Figure 3 shows the curves represented by the following equations (2B-L) and (2C-L), corresponding to equations (2B) and (2C).
T=5.1714×R ^-0.378 ...(2B-L)
T=5.6000×R ^-0.340 ...(2C-L)
If the measurement point on the first imaginary line of the coating satisfies the above requirements, the coating will exhibit superior initial crack resistance and abrasion resistance after contact with alkaline solution in the region near the beltline.

The coating preferably satisfies formula (2B) (preferably formula (2B-b)) and more preferably formula (2C) (preferably formula (2C-b)) at any multiple measurement points on the beltline where the distance between two adjacent measurement points is 5.0 cm or more.
The coating preferably satisfies formula (2B) (preferably formula (2B-b)) and more preferably formula (2C) (preferably formula (2C-b)) at any multiple measurement points on the second imaginary line where the distance between two adjacent measurement points is 5.0 cm or more.

Furthermore, when the inventors performed similar evaluations on several conventional glass laminates having coatings at measurement points along the first dashed line of the coating, they found that the film thickness (T) was approximately 5.0 μm, and the Si/C molar ratio (R) was approximately 0.7 to 0.8, with no coatings satisfying equation (2A).

The film thickness (T) in the region near the belt line of the coating can be adjusted by adjusting one or more conditions, such as the composition of the coating-forming composition (preferably the liquid composition (LC) described below), the solid content concentration, and the amount of coating applied, as well as the positioning angle of the glass substrate during coating of the coating-forming composition.
The Si/C molar ratio (R) in the region near the belt line of the coating can be adjusted, for example, by adjusting the amount of organic groups and organic compounds in the coating-forming composition (preferably the liquid composition (LC) described below).

(Glass substrate)
The glass substrate can include tempered glass, laminated glass made by bonding multiple glass plates with an interlayer, or organic glass, and it is preferable that it includes tempered glass or laminated glass. In Figures 1 and 2, the glass substrate is shown as flat, but for vehicle applications, the glass substrate is processed into a curved shape.

There are no particular limitations on the type of glass sheet used as material for tempered glass and laminated glass, and examples include soda-lime glass, borosilicate glass, aluminosilicate glass, lithium silicate glass, quartz glass, sapphire glass, and alkali-free glass.
Tempered glass is obtained by strengthening a glass plate as described above using known methods such as ion exchange and air-cooled strengthening. Air-cooled tempered glass is preferred as the tempered glass.
The thickness of the tempered glass is not particularly limited, but is preferably 2 to 6 mm.
The thickness of the laminated glass is not particularly limited, but is preferably 2 to 6 mm.

The glass substrate may have a curved shape such that the outer side is convex when installed in a vehicle. If the glass substrate is laminated glass, both the inner and outer glass plates may have a curved shape such that the outer side is convex. The glass substrate may have a single-bend shape curved in only one direction, either left-right or up-down, or a double-bend shape curved in both the left-right and up-down directions. The radius of curvature of the glass substrate may be between 2000 and 11000 mm. The radii of curvature in the left-right and up-down directions may be the same or different. Gravity forming, press forming, and roller forming are used for bending the glass substrate.

The interlayer of laminated glass consists of a resin film. The constituent resin is not particularly limited as long as it is a resin that can bond multiple glass plates well. Preferably, the interlayer contains one or more resins selected from the group consisting of polyvinyl butyral (PVB), ethylene vinyl acetate copolymer (EVA), cycloolefin polymer (COP), polyurethane (PU), and ionomer resin.
The interlayer may contain one or more additives other than resin, as needed.
As the interlayer material, a resin film containing the example resin is preferred.
The interlayer in laminated glass can be either a single layer or a multilayer film.

Examples of materials for organic glass include engineering plastics such as polycarbonate (PC); polyethylene terephthalate (PET); acrylic resins such as polymethyl methacrylate (PMMA); polyvinyl chloride; polystyrene (PS); and combinations thereof. Engineering plastics such as polycarbonate (PC) are preferred.

(film)
The coating contains a siloxane bond (Si-O bond) and one or more organic components selected from the group consisting of organic groups and organic compounds bonded to a Si atom.
The coating can be formed using a coating-forming composition. Preferably, the coating consists of a cured product of a liquid composition (LC) containing one or more hydrolyzable silicon compounds (SCs) having one or more hydrolyzable groups and which may be partially hydrolyzed and condensed with other SCs of the same or different types.

In the coating, organic groups bonded to Si atoms can originate from hydrolyzable organic groups that can be included in hydrolyzable silicon compounds (SC), and/or non-hydrolyzable organic groups that can be included in hydrolyzable silicon compounds (SC). Examples of organic groups bonded to Si atoms include alkyl groups and alkylene groups.
Examples of organic compounds that can be included in the coating include the flexibility-imparting components (FL) described below, the functional components (FU) described below, and components derived therefrom.

<Hydrolyzable Silicon Compounds (SC)>
One or more hydrolyzable silicon compounds (SCs) can harden by hydrolysis condensation to form a silicon oxide matrix. As used herein, the "silicon oxide matrix" is a polymer compound with a high molecular weight, two-dimensionally or three-dimensionally, due to siloxane bonds represented by -Si-O-Si-.

A hydrolyzable silicon compound (SC) is a silicon compound having one or more hydrolyzable groups. The number of hydrolyzable groups bonded to a single Si atom is 1 to 4, preferably 2 to 4, and more preferably 3 to 4. The hydrolyzable groups may be hydrolyzed to hydroxyl groups in the composition.

Examples of hydrolyzable groups include alkoxy groups (including substituted alkoxy groups such as alkoxy-substituted alkoxy groups), alkenyloxy groups, acyl groups, acyloxy groups, oxime groups, amide groups, amino groups, iminoxy groups, aminooxy groups, alkyl-substituted amino groups, isocyanate groups, and halogen atoms. Among these, organooxy groups such as alkoxy groups, alkenyloxy groups, acyloxy groups, iminoxy groups, and aminooxy groups are preferred, and alkoxy groups are particularly preferred. As for alkoxy groups, alkoxy groups with 4 or fewer carbon atoms and alkoxy-substituted alkoxy groups with 4 or fewer carbon atoms (such as 2-methoxyethoxy groups) are preferred, and methoxy groups and ethoxy groups are particularly preferred. As for halogen atoms, chlorine atoms are preferred.
When multiple hydrolyzable groups are present in a hydrolyzable silicon compound (SC), the multiple hydrolyzable groups may be identical or non-identical, but it is preferable that they be identical in terms of the ease of obtaining the raw material.

Preferably, one or more hydrolyzable silicon compounds (SC) include one or more trifunctional hydrolyzable silicon compounds and/or one or more tetrafunctional hydrolyzable silicon compounds. A combination of one or more trifunctional hydrolyzable silicon compounds and one or more tetrafunctional hydrolyzable silicon compounds is preferred. The one or more hydrolyzable silicon compounds (SC) may optionally include one or more bifunctional hydrolyzable silicon compounds.

Tetrafunctional hydrolyzable silicon compounds are compounds having a structure in which four hydrolyzable groups are bonded to one Si atom. Trifunctional hydrolyzable silicon compounds are compounds having a structure in which three hydrolyzable groups are bonded to one Si atom. Bifunctional hydrolyzable silicon compounds are compounds having a structure in which two hydrolyzable groups are bonded to one Si atom.
A hydrolyzable silicon compound (SC) may have two or more structures in one molecule, each in which one or more hydrolyzable groups are bonded to a Si atom.

Hydrolyzable silicon compounds (SCs) may also have functional groups other than hydrolyzable groups. Examples of functional groups other than hydrolyzable groups include epoxy groups, (meth)acryloxy groups, primary or secondary amino groups, oxetanyl groups, vinyl groups, styryl groups, ureido groups, mercapto groups, isocyanate groups, and cyano groups.

Examples of tetrafunctional hydrolyzable silicon compounds include tetramethoxysilane (TMOS), tetraethoxysilane (TEOS), tetra-n-propoxysilane, tetra-n-butoxysilane, tetrasec-butoxysilane, and tetratert-butoxysilane. Tetramethoxysilane (TMOS) and tetraethoxysilane (TEOS) are preferred.

Examples of trifunctional hydrolyzable silicon compounds that do not possess functional groups other than hydrolyzable groups include methyltrimethoxysilane, methyltriethoxysilane, methyltris(2-methoxyethoxy)silane, methyltriacetoxysilane, methyltripropoxysilane, methyltriisopropenoxysilane, methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltriacetoxysilane, and 1,6-bis(trimethoxysilyl)hexane.

Examples of trifunctional hydrolyzable silicon compounds having functional groups other than hydrolyzable groups include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, vinyltris(2-methoxyethoxy)silane, vinyltriisopropenoxysilane, p-styryltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 5,6-epoxyhexyltrimethoxysilane, 9,10-epoxydecyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, and N-(2-aminoethyl)-3-aminopropyl Examples include triethoxysilane, 3-aminopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, di-(3-methacryloxy)propyltriethoxysilane, 3-isocyanatetopropyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-chloropropyltriethoxysilane, 3-chloropropyltripropoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, and 2-cyanoethyltrimethoxysilane.

Examples of bifunctional hydrolyzable silicon compounds include dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldi(2-methoxyethoxy)silane, dimethyldiacetoxysilane, dimethyldipropoxysilane, dimethyldiisopropenoxysilane, dimethyldibutoxysilane, vinylmethyldimethoxysilane, vinylmethyldiethoxysilane, vinylmethyldiacetoxysilane, vinylmethyldi(2-methoxyethoxy)silane, vinylmethyldiisopropenoxysilane, phenylmethyldimethoxysilane, phenylmethyldiethoxysilane, phenylmethyldiacetoxysilane, and 3-chloropropylmethyldimethyl Examples include toxysilane, 3-chloropropylmethyldiethoxysilane, 3-chloropropylmethyldipropoxysilane, 3,3,3-trifluoropropylmethyldimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-acryloxypropylmethyldimethoxysilane, 3-aminopropylmethyldimethoxysilane, 3-aminopropylmethyldiethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropylmethyldiethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, and 2-cyanoethylmethyldimethoxysilane.

The amounts of one or more tetrafunctional hydrolyzable silicon compounds, one or more trifunctional hydrolyzable silicon compounds, and one or more bifunctional hydrolyzable silicon compounds in the liquid composition (LC) are not particularly limited.
The total amount of one or more tetrafunctional hydrolyzable silicon compounds and one or more trifunctional hydrolyzable silicon compounds is preferably 100 to 70 parts by mass, more preferably 100 to 80 parts by mass, and particularly preferably 100 to 90 parts by mass, based on 100 parts by mass of the total amount of one or more hydrolyzable silicon compounds (SC).
The amount of one or more bifunctional hydrolyzable silicon compounds (total amount in the case of multiple types) is preferably 0 to 30 parts by mass, more preferably 0 to 20 parts by mass, and particularly preferably 0 to 10 parts by mass, based on 100 parts by mass of the total amount of one or more hydrolyzable silicon compounds (SC).

For every 100 parts by mass of the total amount of the tetrafunctional hydrolyzable silicon compound and the trifunctional hydrolyzable silicon compound, the amount of one or more tetrafunctional hydrolyzable silicon compounds (or the total amount if there are multiple types) is preferably 30 to 100 parts by mass, more preferably 30 to 95 parts by mass, particularly preferably 40 to 90 parts by mass, and most preferably 50 to 85 parts by mass. The amount of one or more trifunctional hydrolyzable silicon compounds (or the total amount if there are multiple types) is preferably 70 to 0 parts by mass, more preferably 70 to 5 parts by mass, particularly preferably 60 to 10 parts by mass, and most preferably 50 to 15 parts by mass.

As will be described in detail later, the liquid composition (LC) may contain a silylated benzophenone-based UV absorber, which is a reaction product of a hydroxyl group-containing benzophenone-based compound and an epoxy group-containing hydrolyzable silicon compound, as a benzophenone-based UV absorber. This silylated benzophenone-based UV absorber is contained in the hydrolyzable silicon compound (SC) and, like the bifunctional, trifunctional, or tetrafunctional hydrolyzable silicon compounds described above, can form a silicon oxide matrix.

The curing temperature of hydrolyzable silicon compounds (SC) is not particularly limited, but is a temperature exceeding the upper limit of the normal storage temperature, preferably 80°C or higher. The upper limit of the curing temperature is not particularly limited, but from an economic standpoint, it is preferably 230°C. The curing temperature of hydrolyzable silicon compounds (SC) is preferably 150 to 230°C, more preferably 170 to 230°C.

The liquid composition (LC) may optionally contain one or more optional components other than hydrolyzable silicon compounds (SC).

<Silicon Oxide Microparticles (SP)>
The liquid composition (LC) may optionally contain silicon dioxide particles (SP) that are bound to and incorporated in the silicon dioxide matrix within the coating. The inclusion of silicon dioxide particles (SP) in the liquid composition (LC) may improve the abrasion resistance of the coating.
Silicon oxide microparticles (SP) can be incorporated into liquid compositions (LC) in the form of colloidal silica, in which silicon oxide microparticles (SP) are dispersed in water and/or an organic solvent.
The average particle size of silicon oxide fine particles (SP) measured by the BET method is not particularly limited, but is preferably 1 to 100 nm, more preferably 5 to 40 nm, from the viewpoint of improving the transparency and abrasion resistance of the coating. If the average particle size is 100 nm or less, diffuse reflection of light at the particle surface and the resulting decrease in the transparency of the coating can be suppressed.

One or more hydrolyzable silicon compounds (SC) and, if necessary, silicon dioxide microparticles (SP) are components that form the silicon dioxide matrix in the coating. In this specification, these are collectively referred to as matrix components (S).

Here, the content of hydrolyzable silicon compound (SC) in the liquid composition (LC) is expressed as the _SiO2 content when the Si atoms contained in the hydrolyzable silicon compound (SC) are converted to _SiO2 .
The content of one or more matrix components (S) in the total solid content of the liquid composition (LC) (total amount if there are multiple types) is preferably 10 to 90% by mass, more preferably 20 to 60% by mass, as an _SiO2 content.
From the viewpoint of the coating properties of the liquid composition (LC) and the suppression of initial cracks in the coating film, the content of one or more hydrolyzable silicon compounds (SC) in the total solid content of the liquid composition (LC) (total amount if there are multiple types) is preferably 10 to 90% by mass, more preferably 20 to 60% by mass, as an _SiO2 content.
The amount of silicon dioxide fine particles (SP) relative to the total amount of matrix components (S) is not particularly limited, but is preferably 0 to 50% by mass, more preferably 0 to 30% by mass, from the viewpoint of suppressing the formation of initial cracks in the coating and the reduction of transparency of the coating due to aggregation of silicon dioxide fine particles (SP) among themselves.

<Flexibility imparting component (FL)>
The liquid composition (LC) may optionally contain one or more flexibility-imparting components (FL) that improve film formation and suppress initial cracking of the coating.
The flexibility-imparting component (FL) is effective regardless of the type of hydrolyzable silicon compound (SC) used. For example, if the hydrolyzable silicon compound (SC) consists only of tetrafunctional hydrolyzable silicon compounds, the resulting silicon oxide matrix may not be sufficiently flexible. In such cases, using the flexibility-imparting component (FL) can impart appropriate flexibility to the silicon oxide matrix, forming a coating with excellent mechanical strength and resistance to initial cracking.

Examples of flexibility-imparting components (FLs) include organic resins such as silicone resins, acrylic resins, polyester resins, polyurethane resins, epoxy resins, phenolic resins, and hydrophilic organic resins containing polyoxyalkylene groups; curable organic compounds such as monomers, oligomers, or prepolymers that become organic resins upon heating or irradiation with active energy rays; and non-curable organic compounds other than resins, such as glycerin. Known organic resins, curable organic compounds, and non-curable organic compounds can be used.

As the organic resin, a curable resin that hardens upon heating or irradiation with active energy is preferred. Examples of active energy rays include ultraviolet rays and electron beams.
Thermosetting resins, as well as thermosetting compounds such as monomers, oligomers, or prepolymers that become organic resins upon heating, can be cured simultaneously when one or more hydrolyzable silicon compounds (SC) are cured by heating.
Active energy ray curable resins, and active energy ray curable compounds such as monomers, oligomers, or prepolymers that become organic resins upon irradiation with active energy rays, can be cured by heating one or more hydrolyzable silicon compounds (SC) and then irradiating them with active energy rays.
The curable resin and curable compound may undergo a crosslinking reaction with one or more hydrolyzable silicon compounds (SC) during curing.

The content of the flexibility-imparting component (FL) in the liquid composition (LC) is not particularly limited, but is preferably 0 to 100 parts by mass, more preferably 0.1 to 100 parts by mass, and most preferably 1.0 to 50 parts by mass, per 100 parts by mass of the total amount of one or more hydrolyzable silicon compounds (SC).

<Functional Ingredients (FU)>
The liquid composition (LC) may optionally contain one or more functional components (FU). The functions of the functional components (FU) include selective transmission, selective absorption, or selective reflection of light or radio waves in a specific wavelength range; reflection or absorption of heat rays; anti-reflective properties; low reflectivity; low radiation; electrical conductivity; heating properties; water or oil repellency; scratch resistance; stain resistance; antibacterial properties; decorative properties such as coloring; and combinations thereof.
The coating may, for example, include a functional component (FU) such as an ultraviolet shielding agent and/or an infrared shielding agent.

Any known UV shielding agent can be used, and it may be either a UV-absorbing or UV-reflecting type. Preferably, one or more UV absorbers selected from the group consisting of benzophenone-based UV absorbers, benzotriazole-based UV absorbers, benzodithiol-based UV absorbers, azomethine-based UV absorbers, indole-based UV absorbers, and triazine-based UV absorbers are used.

Benzophenone-based UV absorbers include silylated benzophenone-based UV absorbers, which are reaction products of hydroxyl-containing benzophenone compounds and epoxy-containing hydrolyzable silicon compounds. These silylated benzophenone-based UV absorbers are contained in hydrolyzable silicon compounds (SC) and can form a silicon oxide matrix. By using silylated benzophenone-based UV absorbers as UV shielding agents, the UV absorbers can be immobilized on the silicon oxide matrix, and the bleed-out of the UV absorbers can be suppressed. For more information on silylated benzophenone-based UV absorbers, please refer to International Publication No. 2011/142463 , etc.

Known infrared shielding agents can be used, and either infrared absorbing or infrared reflective types are acceptable. Infrared shielding particles are preferred as infrared shielding agents. Metal compound particles containing one or more metal compounds are preferred as infrared shielding particles. For example, metal compound particles containing one or more metal compounds selected from the group consisting of indium tin oxide (ITO), antimond-doped tin oxide (ATO), cesium-doped tungsten oxide (CWO®), fluorine-doped tin oxide ₍ FTO), lanthanum hexaboride ( _LaB6 ), and vanadium pentoxide ( _V2O5 ) are preferred.

As infrared shielding particles, metal compound particles containing cesium-doped tungsten oxide (CWO®) and/or lanthanum hexaboride ( _LaB6 ) are particularly preferred. When these metal compound particles are used, the absorbance of the coating for light with wavelengths of 800 to 1500 nm can be divided by the mass of infrared shielding particles contained per ^m² of the coating, which can be made relatively large, for example, 1.5 or more. In this case, the content of infrared shielding particles in the coating can be reduced. As a result, the absolute number of particles present near the interface between the coating and the glass substrate can be reduced, improving the adhesion between the glass substrate and the coating, and thus improving wear resistance.

When the liquid composition (LC) contains infrared shielding particles, it is preferable to use a dispersion containing infrared shielding particles, an organic solvent as a dispersion medium, and, if necessary, a dispersant, as the raw material for the infrared shielding particles.

<Catalyst>
The liquid composition (LC) may optionally contain one or more catalysts.
If a catalyst is included in the raw materials of the components of a liquid composition (LC), then one or more of the catalysts will contain the catalyst present in the raw materials.
Examples of catalysts include acid catalysts and alkali catalysts. Examples of acid catalysts include inorganic acids such as nitric acid, hydrochloric acid, sulfuric acid, and phosphoric acid; carboxylic acids such as formic acid, acetic acid, propionic acid, glycolic acid, oxalic acid, malonic acid, succinic acid, maleic acid, phthalic acid, citric acid, malic acid, and glutaric acid; and sulfonic acids such as methanesulfonic acid and p-toluenesulfonic acid. Examples of alkali catalysts include sodium hydroxide, potassium hydroxide, and ammonia. Acid catalysts are preferred as catalysts. The catalyst can be used in the form of an aqueous solution.
The content of the catalyst in the liquid composition (LC) is not particularly limited. The content of one or more catalysts (or the total amount if there are multiple catalysts) is preferably 0.01 to 10 parts by mass per 100 parts by mass of the total amount of one or more hydrolyzable silicon compounds (SC).

<Water>
The liquid composition (LC) may contain water, if necessary.
If water is included in the raw materials of the components of a liquid composition (LC), then the water refers to the water contained in the raw materials.
In the film formation process, the hydrolysis condensation reaction of one or more hydrolyzable silicon compounds (SC) can be carried out using moisture in the atmosphere, so the liquid composition (LC) does not need to contain water.
The amount of water in the liquid composition (LC) is not particularly limited, as long as it is sufficient to hydrolyze and condense one or more hydrolyzable silicon compounds (SC). Specifically, an amount of water equal to 1 to 20 equivalents in molar ratio, and more preferably 4 to 18 equivalents, relative to the _SiO2 equivalent amount of one or more hydrolyzable silicon compounds (SC), is preferred.

<Organic Solvents>
The liquid composition (LC) may optionally contain one or more organic solvents as a solvent and/or dispersion medium.
If the raw materials of a liquid composition (LC) contain an organic solvent, then one or more of the organic solvents will be the organic solvents present in the raw materials.

Examples of organic solvents include ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, and acetylacetone; ethers such as tetrahydrofuran, 1,4-dioxane, 1,2-dimethoxyethane, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, and diisopropyl ether; esters such as ethyl acetate, butyl acetate, isobutyl acetate, and methoxyethyl acetate; alcohols such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, 2-methoxyethanol, 4-methyl-2-pentanol, 2-butoxyethanol, 1-methoxy-2-propanol, and 2-ethoxyethanol, and diacetone alcohol; hydrocarbons such as n-hexane, n-heptane, isoctane, benzene, toluene, and xylene; and acetonitrile and nitromethane.

Among the above, alcohols with a boiling point of 80 to 160°C are preferred from the viewpoint of solubility in the liquid composition (LC) and the coating properties of the liquid composition (LC). Specifically, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, 1-methoxy-2-propanol, 2-ethoxyethanol, 4-methyl-2-pentanol, and 2-butoxyethanol are preferred.
As an organic solvent, one or more alcohols may be used in combination with water and one or more other organic solvents other than alcohols that are miscible with alcohol.

The total amount of liquid media such as water and organic solvents contained in the liquid composition (LC) is not particularly limited and can be adjusted to achieve a preferred solid content concentration. The solid content concentration of the liquid composition (LC) is preferably 3.5 to 50% by mass, more preferably 9 to 30% by mass. "Solid content concentration" refers to the total concentration of non-volatile components excluding water and liquid media such as organic solvents.

<Dispersant>
The liquid composition (LC) may optionally contain one or more dispersants for dispersing inorganic fine particles such as infrared shielding particles.
If a dispersant is included in the raw materials of the components of a liquid composition (LC), then one or more of the dispersants are included in the dispersants present in the raw materials.
Known dispersants can be used.

<Chelating agents>
The liquid composition (LC) may optionally contain one or more chelating agents.
When the liquid composition (LC) contains infrared shielding particles and an ultraviolet shielding agent, one or more chelating agents capable of forming complexes with the infrared shielding particles can be used. The chelating agents can coordinate to the surface of the infrared shielding particles and suppress the chelation of the ultraviolet shielding agent to the infrared shielding particles .
If a liquid composition (LC) contains a chelating agent in its raw materials, one or more of the chelating agents will contain a dispersant in the raw materials.

Known chelating agents can be used.
Chelating agents are preferably selected based on their low absorption rate of visible light. The chelating agent is appropriately selected depending on the type of liquid medium, such as water and organic solvents. The liquid medium may include water and/or alcohols, and chelating agents soluble in these polar solvents are preferred. Examples of such chelating agents include carboxylic acids such as maleic acid and (meth)acrylic acid; and (co)polymers thereof (e.g., polymaleic acid and polyacrylic acid).

<Other additives>
The liquid composition (LC) may optionally contain one or more additives other than those mentioned above. Examples of additives other than those mentioned above include surface modifiers, defoamers, viscosity modifiers, adhesion promoters, light stabilizers, antioxidants, dyes, pigments, and fillers.

[Method for manufacturing glass laminates]
The method for manufacturing the glass laminate described above is not particularly limited.
In one embodiment, the method for manufacturing the glass laminate described herein is:
Step (S1) is to prepare a liquid composition (LC) containing one or more hydrolyzable silicon compounds (SC) having hydrolyzable groups,
Step (S2) involves applying a liquid composition (LC) to one surface of a glass substrate to form a coating film, thereby obtaining a glass substrate with a coating film.
The process includes a step (S3) of heating a glass substrate with a coating film to cure the coating film.

(Step (S1))
In step (S1), a liquid composition (LC) is prepared, which contains one or more hydrolyzable silicon compounds (SC) and, if necessary, one or more optional components. The preferred formulation of the liquid composition (LC) has been described above and will be omitted here.
The liquid composition (LC) can be prepared by uniformly mixing one or more materials containing one or more hydrolyzable silicon compounds (SC) using a known method. If the liquid composition (LC) consists of multiple materials, they may be mixed all at once or in stages, and the compounding procedure is not particularly limited.
The ambient temperature in process (S1) is not particularly limited and can be a normal ambient temperature, for example, 10 to 30°C.

(Step (S2))
In step (S2), the glass substrate is positioned approximately horizontally, approximately vertically, or at an inclined angle between approximately horizontal and approximately vertical, and a liquid composition (LC) is applied to one surface of the glass substrate to form a coating film, thereby obtaining a glass substrate with a coating film.
In applications such as vehicle side windows, the glass substrate is typically processed into a curved shape. The coating film can be formed, for example, on the inner surface (usually concave) of the glass substrate.
The coating method is not particularly limited and includes methods such as flow coating, dip coating, spin coating, spray coating, flexographic printing, screen printing, gravure printing, roll coating, meniscus coating, and die coating.
The ambient temperature in process (S2) is not particularly limited and can be a normal ambient temperature, for example, 10 to 30°C.

The film thickness (T) in the region near the beltline of the coating can be adjusted by adjusting one or more conditions such as the composition of the liquid composition (LC), the solid content concentration, the coating amount, and the positioning angle of the glass substrate in process (S2).
A higher solid content concentration in the liquid composition (LC) tends to result in a thicker coating film (T).
A larger amount of liquid composition (LC) applied tends to result in a thicker coating (T).
By adjusting the positioning angle of the glass substrate, the film thickness (T) in the region near the beltline of the coating can be adjusted. For example, in a flow coating method where the region near the beltline of the glass substrate is positioned downwards and the liquid composition (LC) is poured over the glass substrate from above, a position where the glass substrate is nearly perpendicular to the ground tends to result in a thinner film thickness (T) in the region near the beltline of the coating, while a position where the glass substrate is nearly horizontal to the ground tends to result in a thicker film thickness (T) in the region near the beltline of the coating.
The Si/C molar ratio (R) in the region near the belt line of the coating can be adjusted, for example, by adjusting the amount of organic groups and organic compounds in the liquid composition (LC).

(drying process)
Between steps (S2) and (S3), a drying step may be performed as needed to dry the coating film under conditions that prevent the curing reaction from progressing. The drying method is not particularly limited and includes heating and drying at approximately 40-60°C, reduced pressure drying, and reduced pressure heating and drying at approximately 40-60°C.

(Step (S3))
In step (S3), the coated glass substrate is heated to cure the coating. The heating is performed under temperature conditions that cure one or more hydrolyzable silicon compounds (SC). Step (S3) can be carried out in one stage, consisting only of main firing, or in multiple stages, consisting of pre-firing and main firing.
The firing temperature is not particularly limited. When the glass substrate is tempered glass, it is preferably 80 to 230°C, more preferably 100 to 230°C, particularly preferably 150 to 230°C, and most preferably 180 to 210°C. When the glass substrate is laminated glass, it is preferably 80 to 110°C, more preferably 90 to 110°C. The heating time can be appropriately designed depending on the composition of the liquid composition (LC) and the heating temperature.

The orientation of the coated glass substrate in the drying process and step (S3) is not particularly limited. In the drying process and step (S3), the coated glass substrate may be placed substantially horizontally so that the coated film side is facing upwards.
If the liquid composition (LC) contains a thermosetting resin and/or a thermosetting compound, the thermosetting resin and/or thermosetting compound can be cured together with one or more hydrolyzable silicon compounds (SC) in this step (S3).
A coating is formed after this step (S3).

(Step (S4))
If the liquid composition (LC) contains an active energy ray curable resin and/or an active energy ray curable compound, a step (S4) can be performed after step (S3) to cure the active energy ray curable resin and/or active energy ray curable compound by irradiating the coating with active energy rays. Examples of active energy rays include ultraviolet rays and electron beams.
As described above, a glass laminate is obtained.

As described above, this disclosure provides a glass laminate for vehicle side windows and a method for manufacturing the same, which, by optimizing the film thickness and Si/C molar ratio in the region near the beltline of the coating, exhibits good film formation properties, has resistance to initial cracks that can suppress the formation of cracks at the time of film formation (initial cracks), and further possesses excellent abrasion resistance after contact with alkaline liquids.

The present invention will be described below based on examples, but the present invention is not limited to these examples. Examples 1 to 38 are examples, and Examples 101 to 140 are comparative examples.

[Evaluation items and evaluation methods]
The evaluation items and methods are as follows:
(Si/C molar ratio (R))
XPS (X-ray Photoelectron Spectroscopy) analysis was performed using ULVAC-PHIE's "Quantera SXM".
At a specific measurement point on the surface of the coating, XPS analysis and sputtering were repeatedly performed to conduct elemental analysis in the depth direction of the coating, from the surface of the coating to the surface of the glass substrate.
The measurement conditions are as follows:
Probe diameter: 100 μmφ
Measurement area: 100μmφ,
Detection angle: 45° relative to the sample surface.
Pass Energy: 224eV,
Energy Step: 0.4eV/step.
The sputtering conditions are as follows:
Sputter ion species: Ar ⁺ ,
Acceleration voltage: 4kV,
Luster size: 2mm x 2mm
Sputtering interval: 0.5 min/step.

At the measurement points on the coating, the average molar concentration of Si was calculated by averaging the molar concentrations of Si at each depth. Similarly, the average molar concentration of C was calculated by averaging the molar concentrations of C at each depth. The Si/C molar ratio (R) was calculated as the average molar concentration of Si divided by the average molar concentration of C. The amount of Si was determined from the peak value of the Si2p bond energy, and the amount of C was determined from the peak value of the C1s bond energy.

In each example, the Si/C molar ratio (R) was measured at 5.0 cm intervals from one end to the other of the coating, along a first imaginary line created by shifting the beltline 2.5 cm upward along the surface of the coating.
In some cases, the Si/C molar ratio (R) was measured at 5.0 cm intervals along the beltline from one end of the coating to the other, similar to the method described above.
In some cases, similar to the above, the Si/C molar ratio (R) was measured at 5.0 cm intervals from one end to the other of the coating along a second imaginary line, which was created by shifting the beltline 5.0 cm upward along the surface of the coating.
In all examples, the measurement data from multiple measurement points on the same line were uniform.

(Film thickness of the coating (T))
The film thickness (T) [μm] of the coating was measured using the FE-3000 reflectance spectrometer manufactured by Otsuka Electronics Co., Ltd.
In each example, the film thickness (T) was measured at 5.0 cm intervals from one end to the other of the film, along a first imaginary line created by shifting the beltline 2.5 cm upward along the surface of the film.
In some cases, the film thickness (T) was measured at 5.0 cm intervals along the beltline from one end of the film to the other, similar to the method described above.
In some cases, similar to the above, the film thickness (T) was measured at 5.0 cm intervals from one end of the film to the other, along a second imaginary line created by shifting the beltline 5.0 cm upward along the surface of the film.
In all examples, the measurement data from multiple measurement points on the same line were uniform.

(Checking if each equation is satisfied)
In each example, we checked and evaluated whether the film thickness (T) and Si/C molar ratio (R) satisfied the respective formulas.

Does R satisfy equation (3A)?
We checked whether R satisfied equation (3A), and if it did, we determined it was "good (○)"; otherwise, we determined it was "bad (×)".

Does R satisfy equation (4A)?
We checked whether R satisfied equation (4A). If it did, we judged it as "Good (○)," and if it did not, we judged it as "Acceptable (△)."

<Do T and R satisfy equation (1A)?>
The value of [right-hand side of equation (1A)] - [left-hand side of equation (1A)] was calculated. If this calculated value (1A - D) is 0 or greater, T and R satisfy equation (1A), so it was judged as "good (○)". If the calculated value (1A - D) is negative, T and R do not satisfy equation (1A), so it was judged as "bad (×)".

<Do T and R satisfy equation (1B)?>
The value of [right side of equation (1B)] - [left side of equation (1B)] was calculated. If this calculated value (1B - D) is 0 or greater, T and R satisfy equation (1B), so it was judged as "Good (○)". If the calculated value (1A - D) is 0 or greater, and the calculated value (1B - D) is negative, T and R satisfy equation (1A), but not equation (1B), so it was judged as "Acceptable (△)".

<Do T and R satisfy equation (2A)?>
The value of [left side of equation (2A)] - [right side of equation (2A)] was calculated. If this calculated value (2A - D) is 0 or greater, T and R satisfy equation (2A), so it was judged as "good (○)". If the calculated value (2A - D) is negative, T and R do not satisfy equation (2A), so it was judged as "bad (×)".

<Do T and R satisfy equation (2B)?>
The value of [left side of equation (2B)] - [right side of equation (2B)] was calculated. If this calculated value (2B - D) is 0 or greater, T and R satisfy equation (2B), so it was judged as "Good (○)". If the calculated value (2A - D) is 0 or greater, and the calculated value (2B - D) is negative, T and R satisfy equation (2A), but not equation (2B), so it was judged as "Acceptable (△)".

<Do T and R satisfy equation (2C)?>
The value of [left side of equation (2C)] - [right side of equation (2C)] was calculated. If this calculated value (2C - D) is 0 or greater, T and R satisfy equation (2C), so it was judged as "Good (○)". If the calculated value (2A - D) is 0 or greater, and the calculated value (2C - D) is negative, T and R satisfy equation (2A), but not equation (2C), so it was judged as "Acceptable (△)".

(Resistance to initial cracking)
Using an optical microscope (OLYMPUS BX53M), the surface of the coating on the obtained glass laminate (the glass laminate before evaluation of "abrasion resistance after contact with alkaline solution" described later) was observed at 50x magnification.
The film thickness (T) and Si/C molar ratio (R) were measured along the measurement line, and the surface of the film was observed from one end to the other to check for the presence of initial cracks and partial delamination. The evaluation criteria are as follows:
Good (○): No initial cracks are visible.
Acceptable (△): Slight initial cracks were observed, but no partial delamination was seen.
Defective (×): Initial cracks were observed, and partial delamination was also seen.

(Abrasion resistance after contact with alkaline liquid)
The obtained glass laminate was immersed in a 0.1 N sodium hydroxide aqueous solution for 2 hours, then removed, washed with water, and dried in a dryer set to 23°C. A scratch test was performed on the coating of this alkaline-treated glass laminate along the measurement line where the film thickness (T) and Si/C molar ratio (R) were measured, in accordance with JIS K7316 (2013). The load was 10 N.
The surface of the coating after testing was visually inspected. Furthermore, the surface of the coating after testing was microscopically inspected in the same manner as the evaluation of "initial crack resistance" described above. The surface was observed from one end to the other of the coating along the measurement line where the coating thickness (T) and Si/C molar ratio (R) were measured, to confirm the presence or absence of scratch behavior (digging, wedge formation, or cutting) as defined in the JIS standard. The evaluation criteria are as follows:
Grade 1 (Excellent): No scratching behavior was observed at all during visual and microscopic observation.
Grade 2 (Good): No scratching behavior was observed visually, but scratching behavior was observed under a microscope.
Grade 3 (Pass): Slight scratching behavior was observed upon visual inspection.
Defective (×): Clear scratching behavior was observed through visual inspection.

[material]
The materials used in each example are as follows:
<Glass substrate>
(G1) Laminated glass for the side window next to the driver's seat of a commercially available automobile was prepared, as schematically shown in Figure 1.

<Tetrafunctional hydrolyzable silicon compounds (tetrafunctional silanes)>
TMOS: Tetramethoxysilane,
TEOS: Tetraethoxysilane.

<Trifunctional hydrolyzable silicon compounds (trifunctional silanes)>
GPTMS: 3-Glycidoxypropyltrimethoxysilane,
MTMS: Methyltrimethoxysilane,
KBM-3066: 1,6-bis(trimethoxysilyl)hexane, manufactured by Shin-Etsu Chemical Co., Ltd. as "KBM-3066".

<Flexibility imparting component>
(EX-614B) Thermosetting compound, polyfunctional epoxy compound, sorbitol polyglycidyl ether, "Denacol EX-614B" manufactured by Nagase ChemteX Corporation.
(SR-SEP) Thermosetting compound, polyfunctional epoxy compound, sorbitol polyglycidyl ether, manufactured by Sakamoto Pharmaceutical Co., Ltd.
(M-20G) Active energy ray curable compound, methoxydiethylene glycol methacrylate, monofunctional methacrylate, manufactured by Shin Nakamura Chemical Industry Co., Ltd. "M-20G",
(LF-4871) Thermosetting resin, novolac-type phenolic resin, manufactured by DIC Corporation, "LF-4871".

<UV absorbers (UV shielding agents)>
THBP: Dihydroxybenzophenone-based UV absorber, 2,2',4,4'-tetrahydroxybenzophenone, manufactured by BASF as "Uvinul® 3050".
Tinuvin 326: Benzotriazole-based UV absorber, manufactured by BASF as "Tinuvin® 326".
Si-THBP solution (63% by mass): 49.2 g of the above-mentioned THBP, 123.2 g of 3-glycidoxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.), 0.8 g of benzyltriethylammonium chloride (manufactured by Junsei Chemical Co., Ltd.), and 100 g of butyl acetate (manufactured by Junsei Chemical Co., Ltd.) were dissolved by raising the temperature to 60°C while stirring, and then heated to 120°C and reacted for 4 hours to obtain a silylated ultraviolet absorber (Si-THBP) solution with a solid content of 63% by mass. This silylated ultraviolet absorber (Si-THBP) is a functional component and a trifunctional hydrolyzable silicon compound.

<Infrared absorbers (infrared shielding agents)>
ITO dispersion: 20% by mass indium tin oxide (ITO) dispersion. 11.9 g of ITO fine particles (average primary particle size 20 nm, average dispersed particle size 55 nm) manufactured by Mitsubishi Materials Electronic Chemicals, 3.0 g of a dispersant ("DISPERBY K-190" manufactured by BIC Chemie Japan), and 24.2 g of the mixed solvent (AP-1) described below were dispersed using a ball mill for 48 hours. Further dilution with the mixed solvent (AP-1) was performed to obtain the ITO dispersion to an ITO concentration of 20% by mass.
CWO® dispersion: 20% by mass aqueous dispersion of tungsten cesium oxide (manufactured by Sumitomo Metal Mining Co., Ltd. )

<Chelating agents>
PMA-50W: Polymaleic acid aqueous solution, solid content 40-48% by mass, manufactured by NOF Corporation, "Non-Pol PMA-50W"
Maleic acid: 99.0% by mass purity.

<Surface conditioning agent>
BYK307: Silicone-based surface conditioner, manufactured by Big Chemie Japan Co., Ltd.

<Organic Solvents>
AP-11: Ethanol: Methanol: 2-propanol: = 85.5:13.4:1.1 (mass ratio) mixed solvent, manufactured by Nippon Alcohol Sales Co., Ltd., "Solmix (registered trademark) AP-11"
AP-1:Ethanol:2-propanol:Methanol = 85.5:13.4:1.1 (mass ratio) mixed solvent, "Solmix (registered trademark) AP-1" manufactured by Nippon Alcohol Sales Co., Ltd.

<Acid catalyst>
Acetic acid: 99.7% by mass, purity
63% by mass nitric acid aqueous solution.

<Light stabilizer>
LA-72: Hindered amine-based photostabilizer, bis(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, manufactured by Adeka Corporation as "Adeka Stab LA-72".

<Antioxidant>
AO-40: Phenolic antioxidant, 6,6'-di-t-butyl-4,4'-butylidenedi-m-cresol, manufactured by Adeka Corporation as "Adeka Stub AO-40".

[Example 1] (Manufacturing of glass laminates)
(Step (S1))
In a round-bottom flask, 4.55 g of TMOS, 5.19 g of GPTMS, 1.80 g of EX-614B, 3.00 g of THBP, 0.06 g of BYK307, 57.96 g of AP-11, 9.50 g of acetic acid, and 14.50 g of pure water were added and stirred at 50°C for 2 hours. Finally, 3.50 g of 20% by mass indium tin oxide (ITO) dispersion was added to obtain a liquid composition (LC1) with a solid content of 11.6% by mass.
The composition is shown in Table 1-1. The unit of measurement for the amounts in the table is "g".

(Step (S2))
Next, the glass substrate (G1) was placed with its upper edge facing upwards and stood approximately perpendicular to the ground. A liquid composition (LC1) was then poured onto the inner surface (concave surface) of the glass substrate (G1) using a flow coating method with a nozzle, at a distance of several mm to several tens of mm from the upper edge of the glass substrate (G1), so as to follow the upper edge of the glass substrate (G1). In this way, a glass substrate with a coated film was obtained.

(Step (S3))
Next, the coated glass substrate was heated and fired at 200°C for 20 minutes in an air atmosphere. During the firing process, the coated glass substrate was placed horizontally (flat) with the coated film side facing upwards. In this way, the coating film was cured to obtain a glass laminate (GL1), which was then evaluated.

[Examples 2-13, 24-38, 101-140]
(Step (S1))
In Examples 2-13, 24-38, and 101-140, liquid compositions (LC2)-(LC13), (LC24)-(LC38), and (LC101)-(LC140) were obtained in the same manner as in step (S1) of Example 1, except that the compound composition was changed.
The formulations are shown in Tables 1-1 to 1-3, Tables 1-5 to 1-7, and Tables 2-1 to 2-7.
(Step (S2))
Next, the obtained liquid composition (LC) was used to perform coating in the same manner as in step (S2) of Example 1 to obtain a glass substrate with a coated film. However, in these examples, in step (S2), the glass substrate (G1) was placed with respect to the ground at an angle of inclination between approximately horizontal, approximately vertical, or approximately horizontal and approximately vertical.
(Step (S3))
Next, the obtained coated glass substrates were fired in the same manner as in step (S3) of Example 1 to obtain glass laminates (GL2) to (GL13), (GL24) to (GL38), and (GL101) to (GL140), and were evaluated.

[Examples 14-23]
(Step (S1))
In each of Examples 14 to 23, liquid compositions (LC14) to (LC23) were obtained in the same manner as in step (S1) of Example 1, except that the formulation composition was changed.
The formulations are shown in Tables 1-3 and 1-4.
(Step (S2))
Next, the obtained liquid composition (LC) was used to perform coating in the same manner as in step (S2) of Example 1 to obtain a glass substrate with a coated film. However, in these examples, in step (S2), the glass substrate (G1) was placed at an angle of inclination between approximately horizontal, approximately vertical, or approximately horizontal and approximately vertical relative to the ground.
(Step (S3))
Next, the resulting coated glass substrate was fired in the same manner as in step (S3) of Example 1.
(Step (S4))
Next, the active energy ray-curable compound (M-20G) was cured by irradiating the coating with ultraviolet light for 10 minutes using a high-pressure mercury lamp manufactured by GS Yuasa Corporation (peak wavelength: 360 nm, irradiation dose: 500 ^mJ /cm²). In this way, glass laminates (GL14) to (GL23) were obtained and evaluated.

[Summary of Results]
Tables 1-1 to 1-7 show the evaluation results for the glass laminate coatings obtained in each of the 1 to 38 examples, along a first imaginary line obtained by shifting the beltline 2.5 cm upward along the surface of the coating.
Tables 2-1 to 2-7 show the evaluation results of the glass laminate coating obtained in each of the examples 101 to 140, along a first imaginary line obtained by shifting the beltline 2.5 cm upward along the surface of the coating.

The glass laminate coatings obtained in Examples 1 to 38 satisfied equations (1A), (2A), and (3A) at five or more measurement points on a first imaginary line obtained by shifting the beltline 2.5 cm upward along the surface of the coating, where the distance between any two adjacent measurement points was 5.0 cm or more.
The glass laminate coatings obtained in these examples exhibited excellent resistance to initial cracking and abrasion after contact with alkaline solutions, particularly in the region near the beltline.
In some of the examples 1 to 38, equation (1B) was satisfied at five or more measurement points on a first imaginary line obtained by shifting the belt line 2.5 cm upward along the surface of the coating, where the distance between any two adjacent measurement points was 5.0 cm or more.
In some of the examples 1 to 38, equation (2B) or equation (2C) was satisfied at five or more measurement points on a first imaginary line obtained by shifting the belt line 2.5 cm upward along the surface of the coating, where the distance between any two adjacent measurement points was 5.0 cm or more.

The coatings of the glass laminates obtained in Examples 101 to 140 failed to satisfy one or more of the equations (1A), (2A), and (3A) at any multiple measurement points on the first imaginary line where the distance between two adjacent measurement points was 5.0 cm or more.
When the film thickness (T) at the measurement point on the first virtual line of the coating was greater than 8.3741 × R ^-1.871 , the coating in the region near the beltline was thick, resulting in poor initial crack resistance. When the film thickness (T) at the measurement point on the first virtual line of the coating was less than 5.0120 × R ^-0.290 , the abrasion resistance of the coating in the region near the beltline after contact with alkaline solution was poor.

Figure 3 is a graph showing the relationship between the film thickness (T) and Si/C molar ratio (R) at the measurement point on the first dashed line of the coating and the evaluation results for the glass laminate obtained in the [Examples] section. This figure is a graph plotting the data for each example shown in Tables 1-1 to 1-7 and Tables 2-1 to 2-7.
In the diagram, each symbol represents the following examples: "○" indicates an example where both initial crack resistance and abrasion resistance after contact with alkaline solution were good. "▲" indicates an example where abrasion resistance after contact with alkaline solution was good, but initial crack resistance was poor. "◆" indicates an example where initial crack resistance was good, but abrasion resistance after contact with alkaline solution was poor.

Figure 3 shows the curve represented by equation (1A-L), the curve represented by equation (2A-L), and the straight line represented by equation (3A-L). As shown in Figure 3, in the region enclosed by the curves represented by equation (1A-L), the curves represented by equation (2A-L), and the straight line represented by equation (3A-L) (also called the good region), both initial crack resistance and abrasion resistance after contact with alkaline solution were found to be good.

Outside the above-mentioned good range, in the region outside the curve represented by equation (1A-L), initial crack resistance was poor, and in the region outside the curve represented by equation (2A-L), abrasion resistance after contact with alkaline solution was poor.
The curve represented by equation (1A-L) is the boundary curve between the group of examples with good initial crack resistance and the group of examples with poor initial crack resistance, and equation (1A-L) is an empirical formula discovered by the inventors through data analysis.
The curve represented by equation (2A-L) is the boundary curve between the group of examples that showed good abrasion resistance after contact with alkaline solution and the group that showed poor abrasion resistance after contact with alkaline solution. Equation (2A-L) is an empirical formula discovered by the inventors through data analysis.

Figure 3 shows the curve represented by equation (1B-L). Within the range of the good region described above, better results were obtained in the region inside the curve represented by equation (1B-L).

Figure 3 shows the curves represented by equation (2B-L) and equation (2C-L). Within the above-mentioned good region, better results were obtained in the region inside the curve represented by equation (2B-L). Furthermore, even better results were obtained in the region inside the curve represented by equation (2C-L).

As shown in Figure 3, as the Si/C molar ratio (R) increases, the range between the curve represented by equation (1A-L) and the curve represented by equation (2A-L) narrows, and the range of film thickness in which the desired effect can be obtained tends to narrow.
In Figure 3, the Si/C molar ratio (R) at the intersection of the curve represented by equation (1A-L) and the curve represented by equation (2A-L) represents the upper limit of the Si/C molar ratio (R). The upper limit of the Si/C molar ratio (R) was 1.3835.
If the range of film thickness (T) required to achieve the desired effect is narrow, it becomes necessary to strictly control the film thickness (T) within that narrow range, which may lead to a higher defect rate in the manufacturing process.
It was found that if the Si/C molar ratio (R) at the measurement point on the first imaginary line of the coating is 0.8 or less, 0.7 or less, or 0.6 or less, the range of film thickness (T) in which the desired effect can be obtained is relatively wide, eliminating the need for strict control of the film thickness (T) and improving the yield rate of good products in the manufacturing process.

For the glass laminate coatings obtained in Examples 1-4 and 36, evaluations were performed on the beltline, on a first imaginary line obtained by shifting the beltline 2.5 cm upward along the surface of the coating, and on a second imaginary line obtained by shifting the beltline 5.0 cm upward along the surface of the coating. The evaluation results are shown in Tables 3-1 and 3-2. The abbreviations indicating the evaluation locations in these tables are as follows.
BL: On the beltline,
BL+2.5: On the first imaginary line obtained by shifting the belt line 2.5 cm upward along the surface of the coating,
BL+5.0: On a second imaginary line obtained by shifting the beltline 5.0 cm upward parallel to the surface of the coating.

The coatings on the glass laminates obtained in each of the 1-4 and 36 examples satisfied equations (1A), (1B), (2A), (3A), and (4A) at five or more measurement points on the beltline, the first imaginary line, and the second imaginary line, where the distance between any two adjacent measurement points was 5.0 cm or more.
In the glass laminate coatings obtained in each of Examples 1 to 4, equation (2B) was satisfied at five or more measurement points on the beltline, the first imaginary line, and the second imaginary line, where the distance between two adjacent measurement points was 5.0 cm or more.
Furthermore, in the glass laminate coatings obtained in each of Examples 1, 2, and 4, equation (2C) was satisfied at five or more measurement points on the beltline, the first imaginary line, and the second imaginary line, where the distance between two adjacent measurement points was 5.0 cm or more.

The coatings on the glass laminates obtained in Examples 1-4 and 36 exhibited excellent resistance to initial cracking and abrasion after contact with alkaline solutions in the region near the beltline, from the beltline to the second virtual line.

The present invention is not limited to the embodiments and examples described above, and can be modified as appropriate without departing from the spirit of the invention.

1: Glass laminate, 10: Glass substrate, 10S: Surface, 20: Coating, BL: Beltline, IL1: First virtual line, IL2: Second virtual line, NBL1, NBL2, NBL3: Regions near the beltline.

Claims (12)

A vehicle side glass having a glass substrate and a coating formed on one surface of the glass substrate, comprising one or more organic components selected from the group consisting of siloxane bonds, organic groups bonded to Si atoms, and organic compounds, which is installed in a vehicle window opening so as to be openable and closable ,
The coating is formed on the surface of the glass substrate in a region including the window opening when the vehicle side glass is completely closed.
The aforementioned coating is a vehicle side window that satisfies the following equations (1A), (2A), and (3A) when the film thickness and Si/C molar ratio are measured at any number of measurement points on a first imaginary line obtained by moving the vehicle's beltline 2.5 cm upward in parallel along the surface of the coating, with the vehicle side window completely closed at the window opening, in a plan view, where the distance between any two adjacent measurement points is 5.0 cm or more.
T≦8.3741×R ^-1.871 ...(1A)
T≧5.0120×R ^-0.290 ...(2A)
R≧0.4...(3A)
(In the formula, T is the film thickness [μm] and R is the Si/C molar ratio [-].) The vehicle side glass according to claim 1, wherein when the Si/C molar ratio of the coating is measured at any number of measurement points on the first imaginary line where the distance between two adjacent measurement points is 5.0 cm or more, with the vehicle side glass completely closed at the window opening, the following formula (4A) is satisfied.
R≦0.8...(4A) The vehicle side glass according to claim 1 or 2, wherein when the vehicle side glass is in a state where the window opening is completely closed, the film thickness and Si/C molar ratio are measured at any number of measurement points on the first dashed line where the distance between two adjacent measurement points is 5.0 cm or more, the following formula (1B) is satisfied.
T≦7.3741×R ^-1.871 ...(1B) The vehicle side glass according to claim 1 or 2, wherein when the vehicle side glass is in a state where the window opening is completely closed, the film thickness and Si/C molar ratio are measured at any number of measurement points on the first dashed line where the distance between two adjacent measurement points is 5.0 cm or more, the following formula (2B) is satisfied.
T≧5.1714×R ^-0.378 ...(2B) The vehicle side glass according to claim 1 or 2, wherein when the vehicle side glass is in a state where the window opening is completely closed, the film thickness and Si/C molar ratio of the film are measured at any number of measurement points on the first imaginary line where the distance between two adjacent measurement points is 5.0 cm or more, the following formula (2C) is satisfied.
T≧5.6000×R ^-0.340 ...(2C) The vehicle side glass according to claim 1, wherein when the film thickness and Si/C molar ratio are measured at any number of measurement points on the beltline where the distance between two adjacent measurement points is 5.0 cm or more, with the vehicle side glass completely closed at the window opening, the film satisfies the following formulas (1A), (2A), and (3A).
T≦8.3741×R ^-1.871 ...(1A)
T≧5.0120×R ^-0.290 ...(2A)
R≧0.4...(3A) The vehicle side glass according to claim 6, wherein the coating satisfies the following formula (4A) when the Si/C molar ratio of the coating is measured at any number of measurement points on the beltline where the distance between two adjacent measurement points is 5.0 cm or more, with the vehicle side glass completely closed at the window opening.
R≦0.8...(4A) The vehicle side glass according to claim 1 or 6, wherein when the vehicle side glass is in a state where the window opening is completely closed, and in a plan view the beltline is shifted 5.0 cm upward along the surface of the coating, the film thickness and Si/C molar ratio are measured at any number of measurement points where the distance between two adjacent measurement points is 5.0 cm or more, and the following formulas (1A), (2A), and (3A) are satisfied.
T≦8.3741×R ^-1.871 ...(1A)
T≧5.0120×R ^-0.290 ...(2A)
R≧0.4...(3A) The vehicle side glass according to claim 8, wherein the coating satisfies the following formula (4A) when the Si/C molar ratio of the coating is measured at any number of measurement points on the second imaginary line where the distance between two adjacent measurement points is 5.0 cm or more, with the vehicle side glass completely closed at the window opening.
R≦0.8...(4A) The vehicle side glass according to claim 1 or 2, wherein the coating is made of a cured product of a composition containing one or more hydrolyzable silicon compounds having one or more hydrolyzable groups and which may be partially hydrolyzed and condensed among the same or different types. The vehicle side glass according to claim 1 or 2, wherein the coating comprises one or more functional components selected from the group consisting of ultraviolet shielding agents and infrared shielding agents. A step (S1) of preparing a liquid composition containing one or more hydrolyzable silicon compounds having hydrolyzable groups,
Step (S2) is to place the glass substrate on the ground in a substantially horizontal, substantially vertical, or inclined angle between substantially horizontal and substantially vertical, and to apply the liquid composition to one surface of the glass substrate to form a coating film, thereby obtaining a glass substrate with a coating film.
A method for manufacturing a vehicle side glass according to claim 1 or 2, comprising the step (S3) of heating the glass substrate with the coating film to cure the coating film.