KR100648844B1 - A transparent plastic pane of acrylic glass and a process for making the same - Google Patents

Abstract

The present invention relates to a transparent plastic sheet, which generally retains fragments generated at break and which is made of acrylic glass in which the plastic filaments are embedded, wherein the plastic filaments are at least partially protected.

Embedded filaments may be fully and / or partially protected, for example locally. Thereby, it is possible to adjust the matrix adhesive force of the filament so that the fragments generated at break are generally retained without the filament being separated under a thermal stress of -20 to 120 ° C.

Acrylic glass, emulsifier, coating, soundproof wall, PMMA matrix, plastic fiber

Description

A transparent plastic pane of acrylic glass and a process for making the same

The present invention relates to a transparent plastic plate made of acrylic glass with a plastic filament embedded therein which generally retains fragments generated during rupture, a method of manufacturing the same and the use of the plastic plate described above. In particular, the present invention relates to a transparent plastic plate which produces virtually no flakes or rupturable debris upon rupture of the plastic plate, which plastic plate of this kind is suitable for soundproof walls.

Soundproof walls with transparent plastic plates are known, for example, from EP 0 407 852. Plastic plates such as those disclosed in the patent document perform their own functions of preventing the generation and fall of rupturable debris in a unique manner. In the plastic sheet described in the above-mentioned European patent document, additional strings (strips), decorations or pictures may be embedded which serve to protect birds (by recognizing the presence of objects).

European Patent Publication No. 0 531 982 also introduces a transparent plastic plate with a built-in plastic filament that retains fragments that occur in the case of fractures, the plates described in the European patent document serving as bird protection in a particularly aesthetic manner. It has an embedded and rich contrast filament.

The soundproof member according to the prior art can perform its function well, that is, the function of preventing the release of flakes or debris in case of car shock, collision, etc., but in the process of actually using such a plate, the filaments are embedded It has been found that the inherent significantly uniform optical characteristics of transparent plastic plates can sometimes be disturbed by flashing or stray light. This may be due, at least in part, to the embedded plastic filaments being separated from the PMMA matrix of the acrylic glass plates. If part or all of the filament separation occurs, the safety of the debris is seriously threatened by the destruction of the sound barrier, and the total reflection of the light in the PMMA channel in the separated part is inevitably flashing or stray, resulting in aesthetic characteristics. Can adversely affect

Often the only possible cause of filament separation can be speculated. In the relevant temperature range of -20 to 120 ° C., different linear thermal expansion coefficients of the filamentary plastic material and the acrylic glass plate matrix material may be considered. For polyamides, the dependence of the linear thermal expansion coefficient of the filament material on temperature is clearly greater than that of PMMA on the thermal expansion coefficient temperature. This means that one material shrinks at the relevant temperature, while the other material expands. This behavior of the materials can, under certain circumstances, promote the separation of the embedded filaments from the matrix.

In view of the prior art mentioned above, the present invention is directed to providing a transparent plastic plate made of acrylic glass with plastic filaments embedded therein which has excellent uniform optical (visual) characteristics during continuous use under conventional conditions, such as when used as a sound barrier. It is aimed.

It is a further object of the present invention to provide a plate whose optical characteristics are not disturbed by flashing or stray light even after long periods of use and after numerous temperature change cycles.

It is a further object of the present invention that the filament maintains its expandability even upon breakage of the acrylic glass as the optical properties are not affected and at the same time do not have the good positive properties of the known plates, in particular excessive adhesion to the surrounding acrylic glass. To provide a corresponding window or plate that holds the fragments without being destroyed as a result.

In the manufacturing method, the present invention provides sufficient adhesion of the embedded filament to the matrix of the embedded filament, so that fragments that may occur upon window breakage are retained without undesirably separating the filaments during continuous use, for example, as a sound barrier. The aim is to find a simple and advantageous method (process) which can be produced to produce a transparent acrylic glass plastic window (plate) in which plastic filaments are embedded.

Finally, another object of the present invention is to describe the use of a transparent plastic plate made of acrylic glass according to the present invention.

The cited and other objects, which are not specifically mentioned individually but are clearly demonstrated in the introduction, are achieved by the transparent plastic plates of the kind mentioned at the outset with the features of the main body of claim 1.

Preferred embodiments are the subject of product dependent claims that refer to independent claim 1.

Method Technically, the subject matter of claim 7 provides for the solution of the problem based on the present invention. Preferred modified methods are the subject of the dependent claims of claim 7.

Finally, claim 13 relates to the use of the plastic sheet according to the invention.

Surprisingly, in a transparent acrylic glass plastic plate which generally retains debris that occurs upon fracture and is embedded with plastic filaments, the plastic filaments are at least partially protected, thereby retaining the fragments of the embedded filament in an unpredictable manner. It has been found that undesirable flashing or stray light can be avoided without adversely affecting function. Accordingly, it is possible for the first time by the present invention to achieve a soundproof member made of acrylic glass of a good aesthetic and optically satisfactory form, which does not exhibit any adverse optical properties even during long-term use or during normal day and night temperature cycles.

Transparent plastic plates made of acrylic glass according to the present invention are known per se to those skilled in the art. Typical plate thicknesses are 4 mm to 40 mm, preferably 12 mm to 25 mm. Plates are usually manufactured in sizes of 1.5 m x 1 m to 2 m x 3 m, and larger or smaller dimensions are possible for special applications.

The plate is usually largely transparent, preferably colorless or slightly colored in a color such as brown smoke. The transmittance of the colorless transparent plastic sheet is usually at least 70%, preferably 90 to 95%. The transmittance of the colored model is usually 45 to 75%, preferably 50 to 60%.

Embedded plastic filaments typically consist of a plastic matrix incompatible with the polymer matrix of an acrylic glass sheet, preferably polyamide filaments or polypropylene filaments. Single stranded filaments, ie monofilaments, are preferred. Since the plates are usually fixed laterally, the filaments extend horizontally in the plastic plate, with adhesion particularly advantageous at break. Usually the filaments are arranged parallel to each other. If desired or necessary, two layers of filaments extending in two directions can be arranged in the plate, with an angle of 90 ° being particularly advantageous between the filaments of the different layers. This configuration looks like a lattice structure when viewed from the outside.

Of course, one or more of the embedded filaments may be embedded in such a way that they are deflected up to at least 1 mm from an imaginary straight line connecting the filament ends. If the plastic filaments are placed somewhat sagging (suspended) in the acrylic glass matrix, the behavior of the plate suitable as a sound barrier will be determined by the relevant tests under certain circumstances, as is known to those skilled in the art. Become.

The plate according to the invention is characterized in that the embedded plastic filaments are at least partially protected. This means that all plastic filaments can be fully protected or only some, in fact only partially, of plastic filaments embedded in a plate.

In a particularly preferred embodiment, the plastic sheet according to the invention is characterized in that the plastic filaments embedded therein are completely protected.

It may also be desirable for embedded filaments to be partially protected. That is, the filaments are temporarily treated at intervals of 0.5 to 1.5 m, particularly preferably 1 m over a constant length of about 2 to 10 cm. With this AB system of partially protected filaments, it is possible to optimize the embedded filaments to the surrounding acrylic glass matrix to change the matrix adhesion to meet all conventional requirements. With the AB system of partially protected filaments, the major part of the filament, ie the length of most of the filaments, remains loose in the PMMA matrix, as a result of which the principle of action is particularly ensured, nevertheless protected by the above method The filaments can be optimally fixed in the correct position. Therefore, peeling of a filament by a normal day / night temperature cycle can be prevented.

The protected filaments are coated with a buffer residue on at least part of their surface. In principle, all pools containing a suitable agent known to those skilled in the art can be used. In a particularly advantageous embodiment, the plastic sheet according to the invention is characterized in that it is applied by the residue of a hopper containing a phenol-formaldehyde resin in which the filaments are dissolved. Within the scope of the present invention, it has been found that such dissolved formaldehyde resins allow a particularly advantageous concentration range for the protection treatment, while at the same time controlling the attachment of the protected filaments to the matrix.

The present invention also provides a method for producing a transparent plastic plate made of acrylic glass containing plastic filaments generally retaining fragments generated at break, in which the plastic filaments are embedded in acrylic glass, and the filaments It is characterized in that it is processed.

Separation of the filaments from the matrix, which may cause flashing or stray light of the filaments, can be prevented by the protection treatment. As auxiliaries, as already mentioned, all formulations which are being implemented by those skilled in the art for this purpose can be considered. Particularly preferred are those containing dissolved phenol-formaldehyde resins.

In a particularly advantageous variant of the method according to the invention, the filaments are treated with a hose having approximately the following composition before being embedded in the acrylic glass matrix.

Phenolic ≤ 10%

Formaldehyde ≤ 2%

Methanol ≤ 2%

Ethanol ≤ 30%

The phenol-formaldehyde mixture is acid catalytically reacted with para-toluene sulfonic acid and then contacted in a suitable manner with the filaments to be subjected to the protection treatment.

In this case, as already mentioned, the filaments may be in contact with the glue completely, ie corresponding to the full length or locally. After treating the filaments with a foam, the filaments are dried and then embedded in an acrylic glass matrix in a conventional manner.

The adhesion of the protected filaments to the matrix can be affected in several ways. One way is to change the type of appeal. Another method is to change the adhesion to the matrix by controlling the concentration of the inhibitor component in the inhibitor during the treatment. Finally, the filament to be buried is brought into contact with the glue either entirely or locally along its length. In addition, it is also possible to embed fully protected filaments, or partially, ie locally protected filaments, together with unprotected filaments in the same plastic plate.

Regarding the particularly advantageous phenol-formaldehyde resin adjuvant, it has been found that a specific concentration range is particularly advantageous in the treatment treatment. Excessively high concentrations of the constituent components result in excessively high matrix adhesion of the filaments, and as a result, bursting debris may occur in the breaking test of the transparent plastic plate containing the embedded plastic filament according to the present invention. Upon breakdown of the acrylic glass plate, the polyamide filament may break because the adhesion is so large that elongation is no longer possible. In order to avoid this problem with matrix component concentrations (matrix adhesion) and still ensure the advantages of in-plane fixing of plastic filaments, for example, the AB system already mentioned above may be used. In a particularly advantageous variant of the method of the invention, the plastic filaments are protected at intervals of 0.5 to 1.5 m over a length of 2 to 10 cm before being embedded in the matrix, so that the pretreated filaments are embedded in this way. Afterwards, the main part of the filament is relaxed in the PMMA matrix, while the principle of action, ie fixing of the filament, is invariably achieved.

It is also desirable that the concentration of the glue be adjusted so that the matrix adhesion of the filament remains sufficiently strong so that the fragments occurring upon breakage are generally retained, without the filament being separated at thermal stress in the range of -20 to 120 ° C.

Finally, the use of the above plates for soundproof walls also belongs to the present invention.

The invention is explained in detail in accordance with the following examples:

Example 1:

Use the following ingredients.

Solution 1:

Composition:

Phenolic ≤ 10%

Formaldehyde ≤ 2%

Methanol ≤ 2%

Ethanol ≤ 30%

4.940 g of ethanol and 60 g of ^R Araldit K6 (trade name of Ciba-Geigy) for treatment with.

Solution 2:

4.991 g ethanol and 9 g para-toluenesulfonic acid (PTSA).

The two solutions are mixed just before use and the polyamide filament, which is a monofilament, is passed through the mixture, drawn off and introduced into the drying zone. The dried filaments are then used for the production of acrylic glass plates by the chamber process.

In the fracture test of the plates produced in this way, it was confirmed that bursting debris occurred at a concentration of ^R Araldit of 0.6% or more (relative to the sum of Solution 1 and Solution 2). When using ^R Araldit at a concentration ≦ 0.4%, perfect filament adhesion could not be achieved.

Also, no stray light or flash, ie no filament separation, occurred in many day and night cycles in the temperature range of -20 to 120 ° C. The visual characteristics of the plate were excellently uniform and time constant.

Example 2:

It proceeded as in Example 1 except that the filaments were impregnated with a length of 5 cm every 80 cm. At this time, the concentration of the inhibitor was again 0.6%. This variant is advantageous because there is no fear of overuse of the agent, the filament can be secured in the PMMA matrix, and nonetheless the filament is mobile and no disruptive debris has occurred in the fracture test.

Example 3:

As in Example 2, only the coated portions of the polyamide filament are disposed along the edge of the acrylic glass plate. This has the advantage that in the case of possible breakdown, the fixing part of the polyamide plate is not impacted and as a result the working principle of the acrylic glass plate can be further improved.

According to the present invention, it is possible to provide a plastic plate made of acrylic glass which does not cause glare or stray light, in which fragments generated at break are generally retained without the filament being separated under a thermal stress of -20 to 120 ° C. It also provides a simple and advantageous method of manufacturing such plates.

Claims (17)

A transparent plastic plate made of acrylic glass which generally retains debris that occurs upon fracture and has plastic filaments embedded therein, characterized in that the plastic filaments are protected. The transparent plastic sheet as claimed in claim 1, wherein the plastic filaments embedded therein are completely protected. delete The transparent plastic plate of claim 1 wherein the filaments are protected at intervals of about 0.5 to 1.5 m over a length of about 2 to 10 cm. The transparent plastic sheet according to any one of claims 1, 2 and 4, wherein the filaments are covered with a residue of a foam comprising a dissolved phenolformaldehyde resin. The transparent plastic sheet according to any one of claims 1, 2 and 4, wherein the filaments are monofilaments made of polyamide and / or polypropylene. A method for manufacturing a transparent plastic plate made of acrylic glass, which generally contains fragments generated at break and has plastic filaments embedded therein, wherein the plastic filaments are embedded in acrylic glass and protected before the plastic filaments are embedded. Method of manufacturing a transparent plastic plate. 8. A method according to claim 7, wherein the filaments are treated with dissolved phenolformaldehyde resin-based additives. The method of claim 7 or 8, wherein the filaments are protected over their entire length. delete The method of claim 7 or 8, wherein the filaments are protected at intervals of about 0.5 to 1.5 m over a length of about 2 to 10 cm. The concentration of the scavenger according to claim 7 or 8, wherein the filament has a strong matrix adhesive force without separation of the filaments under a thermal stress of -20 to 120 DEG C, so that the fragments generated at the time of fracture can be maintained together generally. Characterized in that is controlled. It is a transparent plastic plate for soundproof walls made of acrylic glass, which generally holds fragments generated at break, and has plastic filaments embedded therein. Transparent plastic plate for soundproof walls, characterized in that the plastic filaments are protected. The method of claim 12, wherein the concentration of the inhibitor is greater than 0.4% and less than 0.6%. It is a transparent plastic plate for soundproof walls made of acrylic glass, which generally holds fragments generated at break, and has plastic filaments embedded therein. A plastic sheet for soundproof walls, characterized in that the plastic filaments are embedded in acrylic glass and protected before the plastic filaments are embedded. 10. The transparent plastic plate as recited in claim 1, wherein the embedded plastic filaments are locally protected. 9. A method according to claim 7 or 8, characterized in that the filaments are locally protected along their length.