JPS61122140A - Production of bent laminated glass - Google Patents

Abstract

PURPOSE:To produce a laminated glass free from delamination, foaming, cracking or strain, by bending a pair of glass plates to a definite angle at the same time, and bonding the glass plates interposing a specific plastic interlayer therebetween. CONSTITUTION:A pair of glass plates 1, 2 cut to a definite shape are stacked. The bending lines 6 formed between the center part 3 and the front and side parts 4, 5 are heated locally with a heater, and the side parts 5 are bent at the same time to a definite angle alpha. A plastic interlayer satisfying the formulas t1{sin(90 deg.-alpha)-0.3}<=t2<=t1{sin(90 deg.-alpha)-+0.3} and 15mil<=t2<=t1 wherein t1 and t2 are the thickness of the center part 3 and the side part 5 of the interlayer, respectively, is inserted between the glass plates 1 and 2, heated at 70-90 deg.C in vacuum to effect the deaeration and the preliminary bonding, and then heated at 110-130 deg.C under 8-13atm to effect the main bonding of the glass plates.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing laminated glass having relatively sharply bent sleeve portions for use in various applications.

Laminated glass is used in various fields where safety is required because it does not scatter pieces when it breaks. For example, when used for vehicles, showcases, stereo racks, record player cover glass, etc.
Due to design and design requirements, the sleeves are relatively sharply bent.

Such relatively sharply bent laminated glass is formed by, for example, sharply bending two glass plates along a desired bending line while heating them with a heater, etc., and then bonding the two glass plates together with a plastic interlayer. are doing. however,
When two glass plates are overlapped and bent, the thickness of the plastic interlayer film is not taken into account, so when the plastic interlayer film is used to join them together, peeling, foaming, cracking, distortion, etc. may occur, and the product may become damaged. It was difficult to obtain products of value.

Therefore, the purpose of Aoi 4-axis is to provide a method for manufacturing bent laminated glass that does not cause peeling, foaming, cracking, distortion, etc. due to the thickness of the plastic interlayer film.

That is, in the present invention, two glass plates are overlapped, and a heater provided along a planned bending line of the two glass plates is heated to simultaneously bend the sleeve portions of the two glass plates into a predetermined position. It is bent at a bending angle α, and the thickness tl of the center part and the thickness tl of the sleeve part are tl (sin(90°-a)
−0,3)≦t2≦tl (sin(90°−α)+O
, 3}, and a plastic interlayer film having the relationship of 1511≦t2<tl is sandwiched between the two glass plates and then laminated.

Therefore, in the present invention, since the thickness tl of the sleeve part is relatively thinner than the thickness tl of the central part of the plastic interlayer film, the gap and bending in the central part formed between the two glass plates The thickness tl, tl of the plastic interlayer film is more likely to be increased by an appropriate %L in the gap in the sleeve portion where the plastic interlayer film is peeled off due to the thickness of the plastic interlayer film.
It can prevent cracking, cracking, distortion, etc.

In practicing the invention, tl and tl are t1{si
n (130°-a)-0,1)≦t2≦J (s
in(Ho-α)+0.1}, and 15mil≦t2<
It is further preferable to have the following relationship.

The bending angle α indicates the angle between the tangent to the sleeve and the center of a relatively sharply bent glass plate, that is, the angle between the sleeve and center of the glass plate as shown in In the case of a straight line, the angle between its tangents XY and PQ, that is, 1
xOQ and 1YOQ are α, and if the sleeve and center portions of the glass plate each have a curved shape with a predetermined curvature as shown in Fig. 7, the angle formed by the respective tangents XY and PQ, ZXO
Q and 1YOQ are α.

In the present invention, as shown in FIG. 3 showing a cross-sectional view, the sleeve portion and the center portion of the relatively sharply bent glass plate may each have a straight shape, or both may have a curved shape. objects or combinations of straight and curved shapes 1
It may also be a term.

Embodiments of the present invention will be described below with reference to the drawings.

The figure shows an embodiment in which the present invention is applied to a cover glass of a record player.

First, as shown in FIG. 1, two glass plates 1.2 are cut into a predetermined shape. That is, the glass plate l,2 has a planar central portion 3. The front part 41 consists of sleeve parts 5.5 on both sides, and a predetermined bending line 6 is set between the center part 3, the front part 4, and the sleeve parts 5.5 on both sides. Further, a mounting hole 7 for a hinge or the like is bored in the rear edge of the central portion 3. Note that the outer and inner glass plates may have the same thickness, but
It is preferable to make the outer glass plate 1 thicker than the inner glass plate 2 from the viewpoint of moldability and impact resistance. Specifically, the thickness of the outer glass plate 1 is 2.0 to 4.0 mm.
Thickness of inner glass plate 2 1.0-3. H shoes are appropriate.

Next, the two glass plates 1.2 are overlapped and softened by heating in heating 1, and then bent at the bending line 6 using the self-weight bending method or press bending method.
Shape as shown in the figure. In this case, in order to make a sharp bend at the bending line 6, it is necessary to locally heat the bending line 6 to a higher temperature. You can use a heater placed in That is, 1.2 glass plates are stacked one on top of the other and placed in a heating furnace, and the whole is heated to 450-eoo°C, preferably 500-550°C, and then the heater is energized to heat the bending line 6 to 850-850°C. Preferably, it is heated to 750 to 800°C and bent at the bending line 6.

In addition, instead of the above-mentioned heater, a ribbon heater attached along the bending line vi6 or a conductive paste such as silver paste printed in a line on the surface of the glass plates l and 2 along the bending line 6 may be used. It is also possible to use a printed heater formed by drying.

After this → hardening, the cross section of the two glass plates 1 and 2 in the bent state shown in FIG. 2 is as shown in FIG. 3. That is, the inner glass pane 2 fits snugly onto the inner surface of the outer glass pane l. When the inner glass plate 2 is translated downward in this state, a gap is created between the glass plates l and 2, but at this time, the gap interval tl at the center and the gap interval t2 at the hem are tl・tl 5
The relationship is in(90°-α). However, α is the bending angle of the glass plate 1.2. Therefore, the plastic interlayer film with uniform thickness is applied to the glass plate 1.2.
If it is interposed between them, the inner glass plate 2 will not fit into the inner surface of the outer glass plate 1. This makes peeling, foaming, cracking, distortion, etc. more likely to occur.

Therefore, in the present invention, the glass plate 1. 2, the thickness tl of the center part and the thickness tl of the sleeve part are tl (sin(90'-(X)-0,3)≦t2≦
t+ (gin(90°-α)+0.3}, and 15a
-iJ≦t2<t+ is used. Here, 0.3 is a value introduced as an allowable range, but if the bending angle is relatively small, for example α
= 30°, t2≦t+ (sin(
90°-30') +0.3)+1.17t1, so there are cases where tl is larger than tl,
The condition tl<t was set. Further, it is more preferable that the present invention has a condition that 15 ail≦t2 is set as the minimum necessary thickness of the brushy interlayer film.
L+ (sin(90°-α)-〇, l)≦t2≦t
+ (sin(90' - α) +0.1}, and 15
It is preferable that 11≦t2<tl.Explaining this in concrete numerical terms, if the bending angle α force is 545°, and the thickness of tl is 3011, it is appropriate that tl is about 2011. When the bending angle α is 60°'', if tl is 30 sil thick, tl is 15+si
Approximately 1 is appropriate. In this way, in order to adjust the thickness tl of the center part of the plastic interlayer film and the thickness tl of the sleeve part, there are two ways to adjust the thickness tl at the center part and the thickness tl at the sleeve part. +/- for the relevant part! Various methods can be employed, such as a method of rolling the plastic interlayer film, a method of stacking two sheets of the plastic interlayer film in the central portion thereof, and the like.

Further, as such a plastic interlayer film, known materials such as polyvinyl butyral, polyurethane, ethylene-vinyl acetate copolymer, silicone resin, etc. can be used.

Next, the plastic interlayer film adjusted as described above is sandwiched between the outer glass plate 1 and the inner glass plate 2. Specifically, a plastic interlayer film is sandwiched between glass plates 1 and 2 and heated to 70 to 80°C in a vacuum state.
After deaeration and pre-pressing, further heat to 110-130°C.
, Perform the main crimping in an autoclave at 8 to 13 atmospheres,
Product.

As shown in FIG. 5, the laminated glass thus made is such that the outer glass plate l and the inner glass plate 2 are connected to the glass plate 1,
The plastic intermediate film 8 interposed between the sleeve portions 5 of 2 is the central portion 3.
Since the glass plates 1 and 2 are relatively thin and have the above-mentioned relationship, the fit between the glass plates 1 and 2 is easy.
Therefore, peeling, foaming, cracking, distortion, etc. are less likely to occur.

In the above embodiments, the present invention was applied to the cover glass of a record player. However, the present invention can also be applied to various types of laminated glass whose sleeve portions are bent at relatively sharp angles, such as for various vehicles and showcases. It can be applied to laminated glass for various other uses.

As explained above, according to the present invention, the thickness of the center part and the thickness of the sleeve parts of the plastic interlayer film are adjusted to be within a predetermined range, so that the plastic interlayer film is not forced onto the outer and inner glass plates. It fits perfectly and prevents peeling, foaming, cracking, distortion, etc.

[Brief explanation of drawings]

Each figure shows one embodiment of the present invention, and the first
The figure is a plan view showing the state in which the glass plate is cut, FIG. 2 is a perspective view showing the state in which the glass plate is bent, FIG. The figure is a cross-sectional view showing a state in which the inner glass plate has been moved in parallel in Figure 3, Figure 5 is a cross-sectional view of a laminated glass, and Figure 6.7 is a cross-sectional view of a relatively sharply bent glass plate. . 1...Outer glass plate, 2...Inner glass plate, 3
...Central part, 5...Sleeve part, 6...Bending line. 8...Plastic interlayer film, tl...Thickness of center part, tl...Thickness of sleeve part, α...Bending angle*
4

Claims (2)

[Claims] (1) Layer two glass plates, heat the heater installed along the planned bending line of the two glass plates, and simultaneously bend the sleeves of the two glass plates at a predetermined angle. It is bent at α, and the thickness t_1 of the center part and the thickness t_2 of the sleeve part are t_1 {sin (90°-α)-0.3}≦
A bending method characterized by sandwiching a plastic interlayer film between the two glass plates, which has a relationship of t_2≦t_1 {sin (90° − α) + 0.3} and 15 mil≦t_2<t_1, and then performing a laminating process. The manufacturing method of laminated glass. (2) In claim 1, t_1 and t
_2 is t_1 {sin(90°-α)-0.1}≦t_
2≦t_1{sin(90°−α)+0.1}, and 1
A method for manufacturing bent laminated glass having a relationship of 5mil≦t_2<t_1.