GB2489728A

GB2489728A - Security glazing and a method of producing the security glazing

Info

Publication number: GB2489728A
Application number: GB1105867.4A
Authority: GB
Inventors: Ross William Curtis
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-04-06
Filing date: 2011-04-06
Publication date: 2012-10-10
Also published as: GB201105867D0

Abstract

Security glazing 2 comprising a first sheet of material, preferably glass 4, a first layer of a resin 6 on an inside face 8 of the first sheet of material 4, security reinforcing 10 for example a grille or grid of bars, which is held in position by the first layer of the resin 6, a second sheet of material 12, and spacer means 14 which is positioned around an edge of the security glazing 2 and between the first and second sheets of material 4 creating a sealed void 18 and the security reinforcing 10 is viewable through at least one of the first and second sheets of material 4, 12. The resin may be clear and/or an ultraviolet cured resin which is 2mm thick and may be poured into the window assembly 32. The void may be sealed by hot melt sealing means or edging tape. A method of manufacturing the security glazing is also defined.

Description

SECURITY GLAZING ANQA METHODQF

PflQDUCING THE SECURITY GLAZING This invention relates to security glazing and, more especially, this invention relates to security glazing comprising sheet material and security reinforcing. This invention also relates to a method of producing the security glazing.

Glazing for buildings, for example in the form of windows or doors, renders the buildings less secure than is desirable because the glazing can be smashed by persons intent on gaining entry into the buildings. Single or double glazing! is easily smashed. Security glazing in the form of toughened or laminated glass is known. Security glazing in the form of a combination of the toughened and laminated glass is also known. The combined toughened and laminated double glass is very strong but, due to the gauge or layers of laminated toughened glass, it can be cost prohibitive to manufacture.

In order to overcome the problem of lack of security cause by the glazing, it is known to mount security grills adjacent the glazing. The security grills may be mounted on the outside of a building or they may alternatively be mounted on the inside of the building. The security grills are secured to edges of the frame or building defining the opening which receives the glazing. Whilst the grills increase security, they also present their own problems. More specifically, the grills may be expensive to install, they may block access to the glazing itself and thus cause difficulty in cleaning the glazing, and they may themselves become dirty and need cleaning. If the grills are mounted on the outside of a building, they need regular maintenance. If the grills are mounted on the inside of a building, they may prevent the operation of curtains and blinds, and the opening of windows.

It is an aim of the present invention to obviate or reduce the above mentioned problem.

Accordingly, in one non-limiting embodiment of the present invention there is provided security glazing comprising a first sheet of material, a first layer of a resin on an inside face of the first sheet of material, security reinforcing which is held in position by the first layer of the resin, a second sheet of material, and spacer means which is positioned around the edge of the security glazing and between the inside face of the first sheet of material and an inside face of the second sheet of material, and the security glazing being such that: (i) a void is formed between the first and second sheets of material and the spacer means; (ii) the void is a sealed void; and (iii) the security reinforcing is viewable through at least one of the first and second sheets of material.

The presence of the resin may assist the void in providing the heat retention and sound excluding properties. The use of the resin enables the security glazing to be produced as safety security glazing, for example with the first and second sheets of material being made of glass. The use of the resin enables the security reinforcing easily and economically to be positioned on the first sheet of material.

The presence of the security reinforcing between the first and the second sheets of material, and with the security reinforcing being held in position by the first layer of the resin, causes the security glazing to be extremely secure. Not only is security provided by the security reinforcing itself, but security is also provided by the first layer of the resin on the inside face of the first sheet of material. For example, the first sheet of material and the.security reinforcing have to be cut through. If a grinder is used, it would take longer than just grinding through the security reinforcing on its own. If bolt cutters are used to try and cut through the security reinforcing, then the bolt cutters are completely unsuitable for cutting through a sheet of material and a layer of resin on the sheet of material, even if the sheet of material has been broken. Thus the security glazing of the present invention provides in many respects belier security than that afforded by known metal grills secured against normal glazing. Still further, with the security glazing of the present invention, the security reinforcing is inside the glazing and thus it does not prevent access to inner and outer faces of the security glazing which are thus always available for cleaning purposes. Still further, because the security reinforcing is inside the security glazing, the security reinforcing does not require maintenance, and it also does not prevent the operation of curtains and blinds, and the opening of windows.

The security glazing of the present invention is thus doubly advantageous in that it overcomes the above mentioned problems with known separate security grills, and it also enables the security reinforcing to have a pleasing aesthetic appearance inside the security glazing.

The security reinforcing in the security glazing of the invention can be viewed through one or both sides of the security glazing in dependence upon whether one or both of the first and second sheets of material are such that they enable the security reinforcing to be viewed through them.

The security glazing may be one of which the first and second sheets of material are of the same material. If desired however the first and second sheets of material may be of different types of material. Preferably the material of the first and second sheets is a transparent or opaque material.

The transparent or opaque material may be glass. Transparent or opaque material other than glass may be employed so that the transparent or opaque material may be a plastics material such for example as a polyacrylate plastics material.

The resin may be a clear resin. Alternatively, the resin may be an opaque resin or a translucent resin. When the first and second sheets of material are glass, then the resin is preferably a glass-laminating resin. The resin may be one that remains pliable and tacky, thereby facilitating the absorption of any expansion and contraction in the security reinforcing. With such a pliable and tacky resin, the sealed void stops the ingress of dust and dirt that would otherwise adhere to the resin, and also the ingress of moisture that could adversely affect the resin.

The security glazing may be one in which the resin is an ultraviolet light cured resin and one that is also a glass-laminating resin and that remains pliable. Other types of curable liquid resins may however be employed. A presently preferred ultraviolet light cured resin and one that is also a glass- * laminating resin and that remains pliable' is that manufactured by the company called Cycol.

The resin is preferably 2mm thick. The resin may be thicker or thinner than 2mm if desired.

* The security glazing may be one in which the resin is poured onto the inside face of the first sheet of material when the first sheet of material is disposed horizontally. The resin is then able to be obtained as an even layer over the inside face of the first sheet of material. The first sheet of material may be disposed in other positions if desired. The first layer of resin will usually extend over the entire inside face of the first sheet of material, but it may extend only partially over the inside face of the first sheet of material if desired.

* The security glazing may be one in which the security reinforcing does not extend more than 10mm from the inside face of the first sheet of material.

The security reinforcing may extend more or less than 10mm from the inside face of the first sheet of material if desired.

Preferably, the void is sealed by a hot melt sealing means. Other types of sealing means may be employed. Preferably the hot melt sealing means is that known as Bortic -5000 hot melt sealing means. Other types of hot melt sealing means may be employed.

Preferably the spacer means is in the form of strips of edging tape as used in double-glazed windows. The strips of edging tape may be secured together at their ends by an adhesive. Preferably the adhesive is a hot melt adhesive. The hot melt adhesive is preferably applied from a hot melt glue gun.

One preferred spacer means is a warm edge system (super spacer) manufactured by Edge Tec. Other warm edge systems may be employed.

Other double glazing spacer systems may be employed, for example aluminium or plastics.

The security glazing may be one in which the void is sealed by sealing means, and in which the sealing means is positioned on an outer edge of the spacer means, the outer edge of the spacer means being such that it extends at right angles to the first and second sheets. In this case, the combined depth of the spacer means and the sealing means defines the depth of a frame portion which extends around the security glazing.

Alternatively, the security glazing may be one in which the void is sealed by sealing' means, and in which the sealing means is positioned on opposite faces of the spacer means, with one of said faces being adjacent the first sheet of material, and the other of said faces being adjacent the second sheet of material. In this case, only the depth of the spacer means needs to define the depth of the frame portion extending around the periphery of the security glazing. This frame portion constituted just by the depth of the spacer means may be thinner than the combined depth afforded by the spacer means and the sealing means when the sealing means is positioned on the outer edge of the spacer means.

Alternatively, the security glazing may be one in which the spacer means is such that it seals the void. In this case, the depth of just the spacer means may again determine the thickness of a frame portion which extends around the periphery of the security glazing.

Alternatively, the security glazing may be one in which at least one, for example two, of its sides are defined by the combined depth of the spacer means and the sealing means, and at least one, for example two, of its sides are defined just by the depth of the spacer means.

In all embodiments of the invention, the security glazing may be one in which the security reinforcing extends out of the first layer of the resin, and in which the resin extends along the side of the security reinforcing in a concave manner and thereby to give a meniscus effect when the security reinforcing is viewed. Thus, when the security reinforcing is viewed, the security reinforcing appears thicker than it is and/or produces an interesting effect.

In one embodiment of the invention, the security glazing comprises only the first layer of the resin.

In another embodiment of the invention, the security glazing comprises a second layer of a resin, the second layer of the resin being provided on the inside face of the second sheet of material. The second layer of the resin may be operative to assist the first layer of the resin holding the security reinforcing in position. The second layer of the resin will usually extend over the entire inside face of the second sheet of material, but it may extend only partially over the inside face of the second sheet of material if desired.

Usually, the second layer of the resin will be the same type of resin as that used for the first layer of the resin. Different resins may be employed if desired.

Usually, the second layer of the resin will be of the same thickness as the first layer of the resin. Differences in thickness between the first and the second layers of the resin may be employed if desired.

In all embodiments of the invention, the security reinforcing may be any suitable and appropriate security reinforcing for providing the required security. Thus, for example, the security reinforcing may be a grid. The grid may be in the form of a mesh or it may be in the form of separate bars. The mesh may be a woven mesh or a welded mesh. The security reinforcing will usually be made of a metal, for example stainless steel, but it may be made of other materials if desired, for example strong plastics materials or Kevlar (Registered Trade Mark).

The security glazing may be one in which the inner face of the first and/or second sheet of material is provided with a pattern.

The security glazing may comprise only the first and second sheets of material to be a double-glazed sealed piece of security glazing.

Alternatively, the security glazing may include a third sheet of material adjacent the outside face of the first or second sheets of material, spacer means, and a void created with the third sheet of material, whereby the security glazing forms a triple-glazed sealed piece of security glazing. If desired, the security glazing could employ more sheets of material and spacer means to give different types of security glazing, for example a quadruple-glazed sealed piece of security glazing.

In another non-limiting embodiment of the present invention there is provided a method of producing security glazing, which method comprises providing a first sheet of material, providing a first layer of a resin on an inside face of the first sheet of material, providing security glazing which is held in position by the first layer of the resin, providing a second sheet of material, and providing spacer means which is positioned around an edge of the security glazing and between the inside face of the first sheet of material and an inside face of the second sheet of material, and the method being such that: (i) a void is formed between the first and second sheets of material and the spacer means; (ii) the void is sealed by the sealing means; and (iii) the security reinforcing is viewable through the first and second sheets of material.

The method of the present invention may be one in which the first and second sheets of material are of the same type of material, If desired, the method of the invention may be one in which the first and second sheets of material are of different types of material. In the method of the invention, the material of the first and second sheets may be a transparent or opaque material. The transparent or opaque material may be glass. If desired, the transparent or opaque material may be other than glass so that, for example the first and second sheets of transparent or opaque material may be of a plastics material such for example as a polyacrylate material.

In the method of the present invention, the resin is preferably a clear resin. The resin may alternatively be an opaque resin or a translucent resin.

In the method of the present invention, the resin is preferably an ultraviolet light cured resin. Other types of liquid cured resins may be employed. A preferred type of ultraviolet light cured resin is that manufactured by the company known as Cycol.

The resin is preferably provided to be 2mm thick. The resin may be provided to be thicker or thinner than 2mm thick.

* The resin is preferably poured onto the inside face of the first sheet of material when the first sheet of material is disposed horizontally. The resin is then formed as an even layer on the inside face of the first sheet of material.

The resin may be poured with the first sheet of material being disposed other than horizontally if desired, The first layer of resin will usually extend over the entire inside face of the first sheet of material, but it may extend only partially over the inside face of the first sheet of material if desired.

In the method of the present invention, the security reinforcing may be chosen to extend not more than 10mm from the inside face of the first sheet of material. The security reinforcing may be chosen to extend more or less than the 10mm from the inside face of the first sheet of material.

The sealing means is preferably a hot melt sealing means. Other types of sealing means may be employed. A preferred hot melt sealing means is that known as Bortic 5000 Hot Melt Sealing Means. Other types of hot melt sealing means may be employed.

In the method of the present invention, the spacer means is preferably provided in the form of strips of edging tape as used in double-glazed windows. The strips may be secured together at their ends by an adhesive.

The adhesive is preferably a hot melt adhesive. Other types of adhesive may be employed. The hot melt adhesive is preferably applied from a hot melt glue + gun.

In the method of the present invention, one preferred spacer means is a warm edge system (super spacer) manufactured by Edge Tec. Other warm edge systems may be employed. Other double edging spacer systems may be employed, for example aluminium or plastics.

The method of the present invention may comprise sealing the void by positioning sealing means on an outer edge of the spacer means, the outer edge of the spacer means being such that it extends at right angles to the first and second sheets of material.

Alternatively, the method of the present invention may comprise sealing the void by positioning sealing means in opposite faces of the spacer means, with one of said faces being adjacent the first sheet of material, and the other of said faces being adjacent the second sheet of material.

Alternatively, the method of the invention may include using the spacer means to seal the void.

Alternatively, the method of the invention may comprise sealing the void by providing at least one, for example two, of the sides of the security glazing with the combined depth of the spacer means and the sealing means, and at least one, for example two, of the sides of the security glazing with just the single depth of the spacer means.

In all embodiments, the method of the invention may comprise providing the security reinforcing in the first layer of the resin such that the security reinforcing extends out of the resin and such that the resin extends along the side of the security reinforcing in a concave manner and thereby to give a meniscus effect when the security reinforcing is viewed.

The method of the present invention may be one in which only the first layer of the resin is provided.

Alternatively, the method of the present invention may comprise providing a second layer of a resin, the second layer of the resin being provided on the inside face of the second sheet of material. The second layer of the resin may be operative to assist the first layer of the resin in holding the security reinforcing in position. The second layer of the resin will usually extend over the entire inside face of the second sheet of material, but it may extend only partially over the inside face of the second sheet of material if desired.

The second layer of the resin is preferably of the same type of resin as that used for the first layer of the resin. Different types of resin may however be employed.

In the method of the present invention1 the second layer of the resin is preferably of the same thickness as the first thickness of the resin. The first and second layers of the resin may however be of different thickness if desired.

The method of the present invention may be such that the provided security reinforcing is as stated above.

* The method of the present invention may include providing the inner surface of the first and/or second sheet of material to give a pattern. This may be done by, for example, pressing the pattern into the surface of the resin.

Usually the pattern will1 be on a pattern maker which is removed after the * pattern is formed in the surface of the resin. The pattern maker may be flexible sheet material which is easily able to be removed from the resin.

The method of the present invention may be employed such that only the first and second sheets of material are provided to give a double-glazed sealed piece of security glazing. Alternatively, the method of the invention may be repeated to provide a third sheet of material adjacent the outside face of the first or the second sheet of material, providing spacer means, and creating a vOid with the third sheet of material, whereby the security glazing forms a triple-glazed sealed piece of security glazing. Alternatively, the method of the invention may be repeated with further sheets of material and spacer means to give different types of sealed pieces of security glazing, for example a quadruple-glazed piece of security glazing.

The security glazing of the present invention will usually be for a window. The security glazing may however be used for other purposes where strength is required, for example for a security partition or for a balustrading unit likely to be subjected to force.

Embodiments of the invention will now be described solely by way of example and with reference to the accompanying drawings in which: Figure 1 is an exploded perspective view of first security glazing of the present invention; Figure 2 is a cross section through the security glazing as shown in Figure 1; Figure 3 is an enlarged view of part of the security glazing as shown in Figure 2; Figure 4 is a cross section like Figure 2 but shows second security glazing of the present invention; Figure 5 is an enlarged view of part of the second security glazing as shown in Figure 4; Figure 6 is a cross section like Figure 2 but shows third security glazing of the present invention; Figure 7 is an enlarged view of part of the third security glazing as shown in Figure 6; Figure 8 is a view like Figure 1 and illustrates a method of producing the securing glazing shown in Figure 1; Figure 9 illustrates part of an alternative method of producing security glazing of the present invention; and Figure 10 shows how two parts of the security glazing shown in Figure 9 are able to be joined together in the method of the invention.

Referring to Figures 1, 2 and 3 there is shown security glazing 2 comprising a first sheet of material 4, and a first layer of resin 6 on an inside face 8 of the first sheet of material 4. The security glazing 2 also comprises security reinforcing 10 which is held in position by the first layer of resin 6. A second sheet of material 12 lays on top of spacer means 14. The spacer means 14 is positioned around an edge of the security glazing 2 and between the inside face 8 of the first sheet of material 4 and an inside face 16 of the second sheet of material 12.

The security glazing 2 is such that a void 18 is formed between the first and second sheets of material 4, 12 and the spacer means 14. The void 18 is a sealed void. The security reinforcing 10 is viewable through at least one of the first and second sheets of material 4, 12. The void 18 causes the viewed security reinforcing 10 to have a three dimensional appearance irrespective of whether the security reinforcing 10 is viewed from the front or sides or the security glazing 2.

The security glazing 2 is such that the first and second sheets of material 4, 12 are of the same material. More specifically, the first and second sheets of material 4, 12 are both transparent. In alternative embodiments of the invention, both the first and second sheets of material, 4, 12 could be opaque, or one sheet of material could be transparent and the other sheet of material could be opaque. The first and second sheets of material 4, 12 are made of glass but in alternative embodiments of the invention, the first and second sheets of material may be made of a plastics material such for example as a polyacrylate material.

The security glazing 2 is also such that the first layer of resin 6 is a clear resin. The clear resin is an ultraviolet cured resin and it is 2mm thick.

The security reinforcing 10 does not extend more than 10mm from the inside face of the first sheet of material.

The void 18 is sealed by sealing means in the form of a hot melt sealing means shown as Bortic-5000 hot melt sealing means.

The spacer means 14 is in the form of strips of edging tape as used in double glazing. The strips are secured together at their end by an adhesive.

The adhesive is a hot melt adhesive. The edging tape is that known as Warm Edgeedging tape.

The security reinforcing is in the form of a grid. The illustrated grid is in the form of a mesh. Alternatively, the grid may be in the form of separate bars, or the grid maybe a woven grid. The security reinforcing is made of a metal. A presently preferred metal is stainless steel. Other metals may be used. Other materials may also be used including strong plastics materials and Keviar (Registered Trade Mark).

Figures 2 and 3 illustrate how the first layer of resin 6 forms a men iscus 20 where it contacts the security reinforcing 10. As can best be seen from Figure 2, the security reinforcing 10 is comprised of a plurality of first bars 22 and second bars 24. The meniscus 20 forms between the first bars 22.

Referring now to Figures 4 and 5, there is shown second security glazing 26. Similar parts as in the security glazing 2 have been given the same reference numerals for ease of comparison and understanding. As can best be appreciated from Figure 5, in the security glazing 2, packer means 28 have been employed to pack or space the first bars 22 of the security reinforcing 10 away from the inside face 8 of the first sheet of material 4. The illustrated packer means 28 are transparent or clear but they may be opaque or non-transparent if desired.

In both the security glazing 2 and the security glazing 26, the security reinforcing 10 is only partially embedded in the first layer of resin 6.

Referring now to Figures 6 and 7, there is shown security glazing 30 which is like the security glazing 2. Similar parts have been given the same * reference numerals for ease of comparison and understanding. In the security glazing 30, the security reinforcing 10 is fully embedded in the first layer of resin 6.

* Referring now to Figure 8, there is shown part of a method of producing the security glazing 2 shown in Figures 1, 2 and 3. It will be seen that the first sheet of material 4 positioned horizontally with the spacer means 14 located on the inside face 8 of the first sheet of material 4. The security reinforcing 10 is inside the periphery of the spacer means 14. The first layer of resin 6 is poured onto the horizontally disposed first sheet of material 4 from a jug 32.

Figures 9 and 10 show part of an alternative method of producing security glazing according to the present invention. As can be seen from Figures 9 and 10, the first sheet of material 4 is provided with a first layer of resin 6. The second sheet of material 12 is provided with a second layer of resin 34. The spacer means 14 is in two parts, with one part of the spacer means 14 being on the inside face 8 of the first of material 4, and the other part of the spacer means 8 being on the inside face 16 of the second sheet of material 12. The first and second sheets of material 4, 12 are brought together as indicated by the arrows 36 in Figure 9 to form seated security glazing as shown in Figure 10 having the void 18. For simplicity of illustration, the security reinforcing 10 has not been shown in Figures 9 and 10.

It is to be appreciated that embodiments of the invention described above with reference to the accompanying drawings have been given by way of example only and that modifications may be effected. Thus, for example, the first and second sheets of material are of the same material and they are in the form of glass. The first and second sheets of different types of material may be employed and they may be other than glass so that they may be, for example, of a plastics material. The resin 8 is a clear resin but it may alternatively be an opaque resin or a translucent resin. Different types of security reinforcing to that shown may be employed. The inner surface of the first and/or the second sheets of material may be provided with a pattern.

Individual components shown in the drawings are not limited to use in their drawings and they may be used in other drawings and in all aspects of the invention.

Claims

CLAIMS1. Security glazing comprising a first sheet of material, a first layer of a resin on an inside face of the first sheet of material, security reinforcing which is held in position by the first layer of the resin, a second sheet of material, and spacer means which is positioned around an edge of the security glazing and between the inside face of the first sheet of material and an inside face of the second sheet of material, and the security glazing being such that: (i) a void is formed between the first and second sheets of material and the spacer means; (ii) the void is a sealed void; and (iii) the security reinforcing is viewable through at least one of the first and second sheets of material.
2. Security glazing according to claim I in which the first and second sheets of material are of the same material.
3. Security glazing according to claim I or claim 2 in which the material of the first and second sheets is a transparent or opaque material.
4. Security glazing according to claim 3 in which the transparent or opaque material is glass.
5. Security glazing according any one of the preceding claims in which the resin is a clear resin.
6. Security glazing according to any one of the preceding claims in which the resin is a ultraviolet cured resin.
7. Security glazing according to any one of the preceding claims in which the resin is 2mm thick.
8. Security glazing according to any one of the preceding claims in which the resin is poured onto the inside face of the first sheet of material when the first sheet of material is disposed horizontally.
9. Security glazing according to any one of the preceding claims in which the security reinforcing does not extend more than 10mm from the inside face of the first sheet of material.
10. Security glazing according to any one of the preceding claims in which the void is sealed by a hot melt sealing means.
11. Security glazing according to any one of the preceding claims in which the spacer means is in the form of strips of edging tape as used in double-glazing.
12. Security glazing according to claim 11 in which the strips are secured together at their ends by an adhesive.
13. Security glazing according to claim 12 in which the adhesive is a hot melt adhesive.
14. Security glazing according to any one of claims 11 -13 in which the edging tape is Warm Edge edging tape.
15. Security glazing according to any one of the preceding claims in which the void is sealed by sealing means, and in which the sealing means is positioned on an outer edge of the spacer means, the outer edge of the spacer means being such that it extends at right angles to the first and second sheets of material.
16. Security glazing according to any one of claims I -14 in which the void is sealed by sealing means, and in which the sealing means is positioned on opposite faces of the spacer means, with one of said facets being adjacent the first sheet of material, and the other of said face being adjacent the second sheet of material.
17. Security glazing according to any one of claims I -14 in which the spacer means is such that it seals the void.
18. Security glazing according to any one of the preceding claims in which the security reinforcing extends out of the first layer of the resin, and in which the resin extends along the side of the security reinforcing in a concave manner and thereby to give a meniscus effect when the security reinforcing is viewed.
19. Security glazing according to any one of the preceding claims and comprising only the first layer of the resin.
20. Security glazing according to any one of claims 1 -18 and comprising a second layer of a resin, the second layer of the resin being provided on the inside face of the second sheet of material, and the second layer of the resin being operative to hold at least one other security reinforcing in position and/or to assist the first layer of the resin in holding the security reinforcing in position.
21. Security glazing according to claim 20 in which the second layer of the resin is the same type of resin as that used for the first layer of the resin.
22. Security glazing according to claim 20 or claim 21 in which the second layer of the resin is of the same thickness as the first layer of the resin.
23. Security glazing according to any one of the preceding claims in which the security reinforcing is a grid or a mesh.
24. Security glazing according to any one of the preceding claims in which the security reinforcing is made of a metal.
25. Security glazing according to any one of the preceding claims in which the inside face of the first and/or second sheet of material is provided with a pattern.
26. Security glazing according to any one of the preceding claims in which the security glazing comprises only the first and second sheets of material to be a double-glazed sealed piece of security glazing.
27. Security glazing according to any one of claims I -25 and including a third sheet of material adjacent the outside face of the first or the second sheet of material, spacer means, and a void created with the third sheet of material, whereby the security glazing forms a triple-glazed sealed piece of security glazing.
28. Security glazing according to claim 27 in which the third sheet of material is the same material as at least one of first and second sheets of material.
29. Security glazing according to any one of the preceding claims and in the form of a window, a partition screen, or a balustrading unit.
30. Security glazing substantially as herein described with reference to the accompanying drawings.
31. A method of producing security glazing, which method comprises providing a first sheet of material, providing a first layer of a resin on an inside face of the first sheet of material, providing security reinforcing which is held in pOsition by the first layer of the resin, providing a second sheet of material, and providing spacer means which is positioned around an edge of the security glazing and between the inside face of the first sheet of material and an inside face of the second sheet of material, and the method being such that: (i) a void is formed between the first and second sheets of material and the spacer means; (ii) the void is a sealed void; and (iii) the security reinforcing is viewable through the first and second sheets of material.
32. A method according to claim 31 in which the first and second sheets of material are of the same material.
33. A method according to claim 31 or claim 32 in which the material of the first and second sheets is a transparent or opaque material.
34. A method according to claim 33 in which the transparent or opaque material is glass.
35. A method according to any one of claims 31 -34 in which the resin is a clear resin.
36. A method according to any one of claims 31 -35 in which the resin is an ultraviolet light cured resin.
37. A method according to any one of claims 31 -36 in which the resin is 2mm thick.
38. A method according to any one of claims 31 -37 in which the resin is poured onto the inside face of the first sheet of material when the first sheet of material is disposed horizontally.
39. A method according to any one of claims 31 -38 in which the security reinforcing does not extend more than 10mm from the inside face of the first sheet of material.
40. A method according to any one of claims 31 -39 in which the sealing means is a hot melt sealing means.
41. A method according to any one of claims 31 -40 in which the spacer means is in the form of strips of edging tape as used in double-glazing.
42. A method according to claim 41 in which the strips are secured together at their ends by an adhesive.
43. A method according to claim 42 in which the adhesive is a hot melt adhesive.
44. A method according to claim 43 in which the hot melt adhesive is applied from a hot melt glue gun.
45. A method according to any one of claims 41 -44 in which the edging tape is Warm Edge edging tape.
46. A method according to any one claims 31 -45 and comprising sealing the void by positioning sealing means on an outer edge of the spacer means, the outer edge of the spacer means being such that it extends at rig ht.angles to the first and second sheets of material.
47. A method according to any one of claims 31 -45 and comprising sealing the void by positioning sealing means on opposite faces of the spacer means, with one of said faces being adjacent the first sheet of material, and the other of said faces being adjacent the second sheet of material.
48. A method according to any one of claims 31 -45 and including using the spacer means to seal the void.
49. A method according to any one of the preceding claims and comprising providing the security reinforcing in the first layer of the resin such that the security reinforcing extends out of the resin and such that the resin extends along the side of the security reinforcing in a concave manner and thereby to give a meniscus effect when the security reinforcing is viewed.
50. A method according to any one of claims 31 -49 and in which only the first layer of the resin in provided.
51. A method according to any one of claims 31 -49 and comprising providing a second layer of a resin, the second layer of the resin being provided on the inner face of the second sheet of material, and the second layer of the resin being operative to assist the first layer of the resin in holding the security reinforcing in position.
52. A method according to claim 51 in which the second layer of the resin is the same type of resin as that used for the first layer of the resin.
53. A method according to claim 51 or claim 52 in which the second layer of the resin is of the same thickness as the first layer of the resin.
54. A method according to any one of claims 31 -53 in which the security reinforcing is a grid.
55. A method according to any one of claims 31 -54 in which the security reinforcing is made of a metal.
56. A method according to any one of claims 31 -55 in which the inner surface of the first andfor second sheet of material is provided with a pattern.
57. A method according to any one of claims 31 -56 in which the security glazing comprises only the first and second sheets of material to give a double-glazed sealed piece of security glazing.
58. A method according to any one of claims 31 -56 and including providing a third sheet of material adjacent the outside face of the first or the second sheet of material, providing spacer means, and creating a void with the third sheet of material, whereby the security glazing forms a triple-glazed piece of security glazing.
59. A method according to any one of claims 31 -58 in which the security glazing is in the form of a window, a partition screen, or a balustrading unit.
60. A method of producing security glazing substantially as herein described with reference to the accompanying drawings.