EP0378560A1

EP0378560A1 - Method for the fabrication of laminated products by assembly of rigid plates and means for implementing such method,

Info

Publication number: EP0378560A1
Application number: EP19880907705
Authority: EP
Inventors: Bernard Follet
Original assignee: Individual
Current assignee: Individual
Priority date: 1987-09-17
Filing date: 1988-09-07
Publication date: 1990-07-25
Also published as: WO1989002366A1; FR2620653A1; FR2620653B1; ES2008028A6; AU2302788A

Abstract

L'invention se rapporte à un procédé de fabrication de produit stratifié par assemblage de plaques rigides, notamment de feuilles de verre au moyen d'un liant liquide durcissable. Ce procédé est caractérisé en ce que l'on dispose les deux plaques (2) dans un plan sensiblement vertical avec leurs faces (5) à assembler sensiblement l'une contre l'autre, on insère, entre les bords des deux faces (5) en vis à vis de l'ensemble (1) une cale d'épaisseur avec laquelle on écarte les deux faces (5) en vis à vis, on déplace la cale d'épaisseur globalement sur toute la périphérie de l'ensemble en écartant à son passage les bords des faces (4) en vis à vis, on oriente ce dernier dans un plan légèrement incliné, par rapport à l'horizontale, on ménage dans le ruban adhésif au moins un orifice (8), on prépare une dose de liant juste nécessaire pour combler le volume (6) réservé par l'espace ''e'' entre les faces (5) en vis à vis des feuilles à assembler, on insère une buse par laquelle on insufle dans le volume (6) un gaz neutre, on coule par gravité entre les plaques la dose de liant (4) qui a été préparée, on ferme alors étanchement l'orifice (8) d'entrée du liant puis, on presse uniformément l'ensemble ainsi préparé et ce sensiblement jusqu'à solidification du liant (4) dans le volume entre les faces (6) et enfin, on retire le ruban adhésif.The invention relates to a method for manufacturing a laminated product by assembling rigid plates, in particular glass sheets by means of a curable liquid binder. This process is characterized in that the two plates (2) are placed in a substantially vertical plane with their faces (5) to be assembled substantially one against the other, and between the edges of the two faces (5) ) opposite the assembly (1) a shim with which the two faces are spread (opposite), the shim is moved overall over the entire periphery of the assembly, in its passage the edges of the faces (4) facing each other, the latter is oriented in a slightly inclined plane, relative to the horizontal, at least one orifice (8) is provided in the adhesive tape, a dose is prepared of binder just necessary to fill the volume (6) reserved by the space '' e '' between the faces (5) opposite the sheets to be assembled, a nozzle is inserted through which it is blown into the volume (6) neutral gas, the dose of binder (4) which has been prepared is poured between the plates by gravity, then the opening (8) of the binder inlet is closed tightly, then, p uniformly resets the assembly thus prepared and this substantially until the binder (4) solidifies in the volume between the faces (6) and finally, the adhesive tape is removed.

Description

PROCESS FOR MANUFACTURING LAMINATE PRODUCT BY ASSEMBLING RIGID PLATES, MEANS FOR CARRYING OUT SAID METHOD AND LAMINATE PRODUCTS PRODUCED ACCORDING TO SAID PROCESS

The invention relates to a process for manufacturing a laminated product by assembling rigid plates, in particular glass sheets by means of a curable liquid binder.

The invention also relates to the means for implementing this method as well as to the laminated products produced according to said method. In particular but not limited to, the invention relates to the assembly of glass sheets or polycarbonate by means of a polymerizable resin such as a methacrylic resin.

In the field of manufacturing laminated glass called flat, to assemble two sheets of glass, almost always using a sheet of thermoplastic binder such as polyvinyl butyral which is placed between the sheets to be assembled prior to prefixing by hot pressing of the assembly in a calender and total fixing by heating in an autoclave. In the case where it is desired to produce laminated panels in shape and / or having to present a high film thickness and a high transparency, it is preferable to assemble the glass sheets by means of a liquid binder such as a resin such as is poured between the sheets after placing means fixing between them the desired spacing and forming at the periphery of the assembly a seal preventing the escape of the resin.

To constitute the means fixing the desired spacing between the sheets to be assembled and forming the joint, a continuous bead of sufficiently firm material is known, such as a butyl bead which is deposited on one of the faces of the sheets to be assembled, in particular at the right of its peripheral edge before approaching the other sheet. When these sheets are of dimensions such that they are capable of deforming under their own weight, to hinder any deformation, it is known to provide between the sheets studs or spacing strips distributed in various places on their facing faces. screw.

For this purpose, h abitue llemen t (FR-A-2145636) is used with spacers which obviously have a thickness corresponding to the desired value of the spacing, but above all are formed from a resin of the same nature. than that to be poured into the volume reserved between the sheets but which has been prepolymerized.

The polymerization of the cast resin and the pads is then carried out by exposure to an ambient temperature of the order of twenty degrees for about twenty four hours, which represents a fairly slow production rate.

For casting, an inclined support receives the assembly consisting of sheets and spacing means in the spacer bead from which the assembly is reserved, in particular at the top of this assembly, a pouring orifice. This manufacturing process makes it possible to obtain assemblies of good quality but despite the identical nature of the material constituting the spacers used, these have, with the resin, a lack of homogeneity which remains discernible. As for the peripheral seal, its elimination requires, after polymerization, to resize the assembly, which is expensive and causes a loss of material.

One result which the invention aims to obtain is a process for manufacturing laminated products and in particular glass sheets by means of a cast binder which does not have the drawbacks of the processes described above.

To this end, the subject of the invention is a process of the aforementioned type, in particular characterized in that:

the two plates are placed in a substantially vertical plane with their faces to be assembled substantially one against the other, - a thickness block is inserted between the edges of the two opposite faces of the assembly at a point on its periphery, with which the two opposite faces are separated and this is substantially of thickness "e "of the binder blade to be poured,

- by keeping it between the opposite faces, the shim is moved overall over the entire periphery of the assembly while spreading the edges of the facing faces with a constant value "e" while as close as possible behind said wedge with respect to its direction of movement, the edges of the two plates are affixed with an adhesive tape which is sufficiently transversely resistant so that when the wedge has moved, it is opposed to the approach of the plates which it connects by sealingly closing the volume reserved between the sheets, with a view to pouring the binder between the faces of the assembly, the latter is oriented in a slightly inclined plane, with respect to the horizontal,

- at one of the angles located at the highest part of the assembly, at least one opening is provided in the adhesive tape,

- also with a view to pouring the binder, a dose of binder is prepared which is just necessary to fill the volume reserved by the space "e" between the faces opposite the sheets to be assembled,

- through a hole, a nozzle is inserted through which a neutral gas such as nitrogen is blown into the volume, separating the central parts of the plates from one another, then,

- Through an orifice, the dose of binder which has been prepared is poured by gravity between the plates, the assembly is gradually brought back to a generally horizontal plane so as to distribute the binder between the faces opposite and to gradually expel by the orifice any gas liable to be retained between said faces, - the binder inlet orifice is then closed tightly, then, - the assembly thus prepared is pressed uniformly and this substantially until the binder solidifies in the volume between the faces and finally,

- we remove the adhesive tape. The subject of the invention is also the means for implementing the method as well as the laminated products thus obtained.

It will be clearly understood with the aid of the description below given by way of nonlimiting example with regard to the attached drawing which schematically represents:

- Figure 1: a partial and profile view of the whole Tors of the spacing of the sheets,

- Figure 2: a cross-sectional view of an assembly ready for casting, - Figure 3: a cross-sectional view of a finished assembly,

- Figure 4: seen in section along a plane parallel to one of the plates, the assembly during the casting of the binder.

Referring to the drawing (Figure 3), we see in cross section an assembly 1 of at least two plates 2 of rigid material, among which we will understand any plate of composite material or not of significant transverse and longitudinal dimensions compared to its thickness, like sheets of glass, these plates 2 are assembled by a blade 3 of binder which unites them by their faces 5 opposite.

As has also been shown (FIG. 4), the binder occupies the volume 6 between the faces 5 without a solution of continuity and this from one edge 7 to the other of the assembly.

To achieve the desired result, after possible preparation of the glass sheets to be assembled, for example, after cleaning the faces 5 intended to be joined by the binder 4 or even after treatment to promote the adhesion of the resin, instead of depositing a spacer cord on the face of one of the sheets. 2 and then to adjust the other sheet 2 on the latter, in accordance with the invention:

the two plates 2 are placed in a substantially vertical plane with their faces 5 to be assembled substantially one against the other, - Is inserted between the edges of the two faces 5 opposite the assembly 1 at a point on its periphery, a shim with which we move the two faces 5 opposite and this substantially from thickness "e" of the blade 3 of binder 4 which must be poured,

- by keeping it between the facing faces 5, the shim is moved overall over the entire periphery of the assembly while spreading the edges of the facing faces 4 with a constant value "e "while as close as possible behind the said wedge with respect to its direction of movement, the edges 7 of the two plates 2 are affixed with an adhesive tape which is sufficiently resistant transversely so that when the wedge has moved, the plates which '' it connects while sealingly closing the volume 6 reserved between the sheets,

- in view of the casting of the binder 4 between the faces 5 of the assembly, the latter is oriented in a slightly inclined plane, relative to the horizontal,

- at one of the angles located at the highest part of the assembly 1, at least one orifice 8 is housed in the adhesive tape,

- also with a view to pouring the binder, a dose of binder is prepared which is just necessary to fill the volume 6 reserved by the space "e" between the faces 5 opposite the sheets to be assembled,

- through an orifice 8, a nozzle is inserted through which a neutral gas such as nitrogen is blown into the volume 6, separating the central parts 5 of the plates from one another, then,

- Through an orifice 8, the dose of binder 4 which has been prepared is poured by gravity between the plates, the assembly is gradually brought back to a generally horizontal plane so as to distribute the binder 4 between the faces 5 opposite and to progressively expel through the orifice 8 any gas liable to be retained between the said faces 5, then the orifice 8 for entering the binder is closed tightly, the assembly thus prepared is pressed uniformly and this substantially until the binder 4 solidifies in the volume between the faces 6 and finally,

- we remove the adhesive tape. Preferably, an adhesive tape having a width greater than the thickness of the assembly is chosen and it is affixed so as to reserve a margin on each side, then the margins are folded over the edges of the external faces of the sheets.

During casting, the inclination of the table relative to the horizontal is of the order of fifteen degrees.

According to a characteristic of the invention, instead of pressing the assembly in a plate press, the assembly is pressed in a roller press which distributes the binder uniformly by successively laminating the assembly to a dimension "c" linked to the value "e" of the initial spacing between the edges of the faces 5.

Preferably, at least until the solidification of the binder begins, the assembly produced is pressed at a temperature such that the hardening is activated, for example by polymerization or binder 4.

For example, the binder will consist of an acrylic resin, the polymerization of which will be obtained by pressing at a temperature of approximately seventy five degrees celsius for twenty minutes. It will be chosen to guarantee:

- good adhesion on the leaves,

- the maximum fluidity to be introduced by gravity in a minimum of time,

- the correspondence to the standards of the finished products, - the polymerization fast enough to avoid investments too expensive,

- long-term durability.

About 1% of a compound will be added which produces chemical bonds between the sheets and the usual resin compounds to which this additional compound also combines or for unsaturated bonds, The resin being introduced by gravity at a pressure of the order of 150 gr / cm ² into a space of low height (for example around 1.42 mm) its viscosity at the time of casting is chosen to be very low. For example, the mixture will have a dynamic viscosity of around 10 ^-3 pascal / second, a viscosity close to that of water at a temperature of twenty degrees. Under these conditions, a flow rate of the order of twenty liters per minute can be obtained.

A plasticizer is added thereto which does not polymerize with the abovementioned resins but is interposed between the meshes of the polymerized network so that the assembly retains elastic properties in a good temperature range.

At the time of use, that is to say three hours before processing, a few traces of a product are added which will serve as a reaction accelerator and the mixture is then deaerated.

About 1% of a product is added at this point which will serve as a catalyst during the polymerization.

In an enclosure heated to seventy degrees Celsius, the exothermic reaction will occur approximately after a quarter of an hour but the temperature reached by the film then formed will not exceed seventy eight degrees Celsius.

Adding an additional quantity of accelerator in order to reduce the polymerization time is not recommended because it would lead to temperatures exceeding eighty degrees and there would then be a risk of bubbling of the resins and therefore of bubbles in the film.

The means for implementing the method of the invention obviously include a tilting support such as a ball table which makes it possible to receive and orient sets of glass sheets under good operating conditions, but above all, at least one means 9 which makes it possible to connect the edges 7 of the sheets 2 securely and tightly.

This means 9 consists of an adhesive tape of material and of cross section chosen to have a transverse resistance at least sufficient to maintain alone the spacing between the edges of the plates despite the weight of the top sheet and then the action of the press. . The means further comprise a device 10 for spreading sheets and for depositing means 9 which comprises:

a means of support on the edges 7 of the leaves,

- With, on the one hand at least one wedge 11 of local spacing and, on the other hand, a means of depositing on these edges 7 of the sheets 2 of the means 9 responsible for securely connecting them by sealingly closing the volume between the faces opposite.

The shim is adjustable or interchangeable so as to adapt to the desired thickness.

Of course, this device also comprises a gripping means (not shown) for its control either manually or by a mechanical or even automatic device.

Separately or in combination with the device 10, the means for implementing the invention also comprise, when the means 9 is advantageously of width greater than the total thickness of the assembly 1, a means 12 for folding the margins 13 of the means 9 on the edges of the outer faces 14 of the glass sheets such as a fork whose branches are adjustable in spacing symmetrically to the axis of the ribbon.

Advantageously, the connecting means 9 between the edges of the sheets is a metal strip, for example made of aluninium.

As an indication, good results have been obtained with aluminum strips of a thickness of the order of thirteen hundredths of a millimeter.

Its adhesive is chosen so as to be compatible with the binder, that is to say the components of which do not migrate through the resins where they could cause defects such as bubbles, occlusions, etc.

The means for implementing the invention also comprise a preferably hot roller press such as a calendering machine, which makes it possible to obtain:

- uniformity of temperatures for mass polymerization at the same time,

- temperature regulation to avoid overheating when the exothermic "peak" occurs during the polymerization of the resin, - by the nature and the weight of the rollers, a sufficient pressure for the distribution of the resin but which remains low enough not to blow up the peripheral seal,

- a speed fast enough to obtain a good yield but limited so as not to require a calender of excessive length.

The enclosure of the calender is advantageously insulated by means of green wool and polystyrene plates. Given the relatively low temperatures in the workshop housing the calendering machine, preferably all the mechanical elements will be enclosed therein except the motor-reduction unit used for the rotation of the rollers and the motor-fan group used for heating. Advantageously, the heating mode is forced horizontal convection.

The fan permanently draws air from the calender on one side and expels it on the other.

The hot air inlet and outlet openings are located along the entire length of the calendering machine between each roller on either side of the glass surfaces so as to lick them tangentially.

The air is introduced under a pressure of more or less 200 mm of water. Between the fan outlet and the intake nozzle, there is a resistance coil which heats the air.

In order to have good temperature uniformity, it is necessary to make the enclosure as watertight as possible while at the same time allowing, by means of automatically retracting rubber flaps, to allow the volumes of glass to enter and exit easily.

In order to avoid cold air entering which could be induced by certain interstices, the assembly is kept under a pressure of a few millimeters of water ensuring a slight leak rate at all points. This precaution is ensured by having adjustable valves on the fan intake which admit cold air taken into the manufacturing workshop.

The heating block consists of several and for example three resistors of 15 Kw.

Some, for example two are generally in permanent service except in summer during very high outside temperatures where generally only one is sufficient.

A single measurement point is introduced, the room thermostat is sufficient to operate the installation correctly.

The set point varies little and depends almost entirely on the temperature prevailing in the workshop.

The rolls will for example be one hundred and thirty with a diameter of 170 mm and a weight of about 80 kg.

They consist of a steel core covered with a rubber coating with a hardness of between eighty degrees and ninety degrees shore A.

They are arranged in pairs. The horizontal distance between two rollers is 200 mm.

The vertical distance obviously depends on the thickness of glass introduced.

For example, to have a resin thickness of 1.2 mm between two 4 mm glass panes, the rollers should be placed at 1.2 + 4 + 4 + 0.25 or 9.45 mm.

The last value of 0.25 mm represents the shrinkage of the resin during the polymerization.

The speed of advance of the volumes must not be less than 60 cm / min. Polymerization occurs when the glasses are still pressed by the rollers.

As there is necessarily a difference in temperature between a roller and the surrounding air, if Your speed was too low, there would be a risk of delayed polymerization. A part at higher temperature would react with another at a lower temperature and on the finished product would appear "markers" in the form of successively clearer and more forced bands. It should be noted that once the polymerization is complete, the upper rollers are no longer useful.

Due to the withdrawal that occurred, they separated from the ice. In order to control all the phenomena, windows in insulating glass were placed on the roof of the calendering machine in order to be able to observe by means of heat-sensitive papers stuck on the upper windows if the cycle is proceeding normally. The process takes place as follows:

Before the glass is introduced into the washing machine, it is necessary to fold the edges of the four corners of the volumes so as to avoid tearing of the adhesive tape during its installation. It is preferable to have a vertical washing machine.

Otherwise, an additional glass lifting operation is necessary because one cannot place a glass on the other flat, the glasses freezing each other. Coming out of the washing machine, the ice creams are placed on a ball table raised to eighty five degrees.

Cleats located at the bottom support the glasses.

The adhesive tape is then unrolled on the three accessible sides and the edges are folded down.

The table is then tilted horizontally, the cleats that held the glass are retracted and the adhesive tape is rolled out on the fourth side.

On one corner, we temporarily leave two three centimeters uncovered on the other about ten centimeters.

Other cleats are out on the other side of the table, we tilt it a few degrees, the glasses rolling on the balls will rest there. ar the three centimeters left free on an edge, is introduced for about three seconds, under a pressure of 200 gr for a 2 mm orifice, nitrogen to slightly spread the volumes and facilitate the introduction of the resin. This corner is then filled in and the resin is introduced through the other corner by means of a hollow spatula, the quantity of resin required having been previously made available.

By deformation of the glasses, the resins occupy about half of the apparent volume.

A suction cup is also applied to the upper glass at the place of filling to slightly separate the two glasses.

The flow is improved and the introduced nitrogen can escape.

The table is then tilted back to a horizontal position and by means of light pressure on the glasses, the resin is evenly distributed in the space it did not occupy. We. guides the last nitrogen bubble towards the filling area which is now only a few millimeters open.

When the resin will escape, we close the corner.

The glass is then introduced into the calender. He will stay there for about twenty minutes.

As soon as it comes out, the adhesive tape is removed using scrapers.

The volume which has been pushed onto another ball table is then raised vertically by means of a vacuum lifter and placed on a desk, ready for dispatch.

In an eight-hour day, two agents made 600 m ² of laminated glass called "MM44" by this method.

Claims

1. Method for manufacturing laminated products by assembling rigid plates (2) such as glass sheets using a curable binder (4) cast between the faces (5) opposite said plates (2) which, prior to their assembly, may have been prepared and in particular cleaned, this process being CHARACTERIZED in that: the two plates (2) are arranged in a substantially vertical plane with their faces (5) to be assembled substantially one against the 'other,

- between the edges of the two faces (5) opposite the assembly (1) at a point on its periphery, a shim is inserted with which the two faces (5) are spread opposite and this substantially of the thickness "e" of the blade (3) of binder (4) which must be poured,

- by keeping it between the faces (5) opposite, the shim is moved overall over the entire periphery of the assembly, while spreading the edges of the faces (4) opposite a constant value "e" while as close as possible behind the said shim with respect to its direction of movement, the edges (7) of the two plates (2) are affixed with an adhesive tape that is sufficiently resistant transversely for when the shim has moved to oppose the bringing together of the plates which it connects while sealingly closing the volume (6) reserved between the sheets,

- in view of the casting of the binder (4) between the faces (5) of the assembly, the latter is oriented in a slightly inclined plane, with respect to the horizontal, - at one of the angles located at the highest part of the assembly (1), at least one opening (8) is provided in the adhesive tape,

- also with a view to pouring the binder, a dose of binder is prepared which is just necessary to fill the volume (6) reserved by the space "e" between the faces (5) facing the sheets to be assembled, - through an orifice (8), a nozzle is inserted through which a neutral gas such as nitrogen is blown into the volume (6) separating the central parts (5) of the plates from one another, then

- By an orifice (8), the dose of binder (4) which has been prepared is poured by gravity between the plates, the assembly is gradually brought back to a generally horizontal plane so as to distribute the binder (4) between the faces (5) opposite and gradually expelling through the orifice (8) any gas capable of being retained between said faces (5),

- then the opening (8) of the binder inlet is closed tightly, then,

- the assembly thus prepared is pressed uniformly and this substantially until the binder (4) solidifies in the volume between the faces (6) and finally,

- we remove the adhesive tape.

2. Method according to claim 1 characterized in that an adhesive tape is chosen having a width greater than the thickness of the assembly and it is affixed so as to reserve a margin on each side then the margins are folded over the edges of the outer sides of the leaves.

3. Method according to claim 1 or 2 characterized in that the assembly is pressed in a roller press which distributes the binder uniformly by successively laminating the assembly to a dimension "c" linked to the value "e" of the initial spacing between the edges of the faces (5).

4. Method according to any one of claims 1 to 3 characterized in that the assembly produced is pressed at a temperature such that activates the hardening of the binder (4).

5. Means for implementing the method according to any one of claims 1 to 4 characterized in that they comprise at least one means (9) which makes it possible to securely and tightly connect the edges (7) of the sheets (2 ).

6. Means according to claim 5 characterized in that the means (9) consists of an adhesive tape of material and cross section chosen to have a resistance transverse at least sufficient to maintain alone the spacing between the edges of the plates despite the weight of the upper sheet and then the action of the press.

7. Means according to claim 5 or 6 characterized in that they comprise a device (10) for spreading sheets and depositing means (9) which comprises:

a means of support on the edges (7) of the sheets,

- With, on the one hand at least one wedge (11) of local spacing and, on the other hand, a means of depositing on these edges (7) sheets (2) of the means (9) responsible for connecting them securely by sealing the volume between the opposite faces.

8. Means according to any one of claims 5 to 7 characterized in that they also comprise, when the means (9) is advantageously of width greater than the total thickness of the assembly (1), means (12 ) folding the margins (13) of the means (9) on the edges of the outer faces (14) of the glass sheets.

9. Product laminated by assembling rigid plates (2) using a binder (4) poured between their faces opposite, characterized in that it is produced according to the process which is the subject of any one of claims 1 to 4.