A SHEET MATERIAL

Abstract: A sheet material (10) for use in construction, comprising a first support surface (11) including a plurality of perforations (13) arranged in a predetermined pattern and a plurality of optical members (15), each said optical member being received in one said perforation. Also envisaged is a sheet material comprising a second support surface (12) including a plurality of perforations in register with the perforations in said first support surface. In this embodiment each said optical member (15) is received in one said perforation in each of said first and second support surfaces.

Description: A SHEET MATERIAL TECHNICAL FIELD The present invention is concerned with a sheet material and, more particularly with a sheet material which creates an optical effect with aesthetic appeal. BACKGROUND ART Sheet materials used in construction often have decorative finishes applied to them to enhance their aesthetic appeal. For example, laminated panels used in building often have a core of plywood with a thin sheet of a suitable material bearing a wood-grain pattern or other decorative indicia bonded to one or both sides. However, optical effects with aesthetic appeal have not hitherto been employed in the decoration of sheet materials . United States patent number 3,666,605 describes a laminated panel having a covered, concealed window, useful in the roof of a vehicle and other structures . The laminated panel comprises a core made of plywood, plastic foam, aluminium or other known construction material which is covered on both sides with a protective thermoplastic or thermosetting plastics material. One or more holes is formed in the core and through one of the protective layers, but not through the other protective layer. A window pane made of a transparent material such as lucite, acrylic plastic or glass, is inserted in the hole to allow light to be transmitted from one side of the panel to the other, for example into the interior of a vehicle. The outer side of the laminated panel has no perforations in the protective layer and so presents an intact appearance to an observer outside the vehicle. Moreover, the laminated relies on this non-perforated protective layer to provide a barrier to transmission of dust or moisture into the interior of the vehicle or other structure whilst still transmitting as much light as possible to the interior. In this way the laminated panel described in US patent number 3,666,605 overcomes the problem associated with existing window arrangements in vehicles and other structures, of leakage around the window frame when glazing is not adequately sealed when secured in said frame. DISCLOSURE OF INVENTION According to a first aspect of the invention there is provided a sheet material for use in construction, comprising a first support surface including a plurality of perforations arranged in a predetermined pattern and a plurality of optical members, each said optical member being received in one said perforation. Typically, said sheet material is decorative. In one embodiment of the invention, each said perforation is a raised annular lip adapted to receive said optical member. Each said optical member may be secured in the desired perforation with adhesive applied to said raised annular lip, but may be secured by any other convenient means. For example, said optical member may be retained in said perforations merely due to the tightness of the fit, or a gasket of metal or other substance may lock said optical members in said perforations . Typically each said optical member protrudes from said first support surface in at least a first direction. Said optical members may also protrude from said first support surface in a second direction, typically the direction opposite to said first direction. Typically in the former case, said optical member is generally spherical in shape. The generally spherical optical member may sit upon the raised annular lip if the sphere is larger in diameter than said perforation. Alternatively, it could be received in the underside of said raised annular lip, particularly where said raised annular lip is frusto- conical in shape and said optical member is spherical. In the latter case said optical member is typically dome- shaped and has a curved surface disposed to one side of said first support surface and a flattened surface disposed to the other side of said first support surface. Either or both surfaces in either case may be the one disposed towards the observer with the desire to create an optical effect with aesthetic appeal to that person. Preferably, said globular member is larger than each said perforation. Typically, said perforations are arranged in a grid array. However, any pattern which may create an optical effect with aesthetic appeal to an observer (when the optical members are inserted) can be used. Various indicia may be created by arranging said perforations in different patterns and using different combinations of the various optical members available. Typically said first support surface is made of metal, but any suitable material may be used. As used throughout the description and claims of the present application the term -"optical member" is a member which creates an optical effect with aesthetic appeal. By way of example only, said optical member may be globular mass of a light transmissive material such as glass, whereby a desirable visual effect is created by transmission of light through said light transmissive material and/or by reflection of light from said coloured material. Said light transmissive material may be coloured. It will be appreciated that use of a plurality of such optical members will create the effect of an array of individual points of bright colour, said colours being the same or different, which is an image generally pleasing to the eye. As another alternative, said optical member may be a globular mass of a translucent material, whereby transmission of light through said material creates a plurality of individual points of diffuse, transmitted light of relatively low intensity so as to create a desirable visual effect. In a particularly preferred embodiment of the invention said sheet material further comprises a second support surface including a plurality of perforations in register with the perforations in said first support surface, whereby each said optical member is received in one said perforation in each of said first and second support surfaces . Advantageously, said second support surface is secured to said first support surface in spaced apart disposition. Typically said optical members are clamped between said second support surface and said first support surface. They may, however, be secured between said first and second support surfaces by any possible means, or other means of securing said optical members may be employed in conjunction with this means of securing said optical members. For example, adhesive may be applied to either one or both of said first and second support surfaces before clamping pressure is applied to said optical members . Typically said second support surface is made of the same material as said first support surface and has the same characteristics . The perforations in each of said first and second support surface must be in register and, typically, this requires said first and second support surfaces to be superimposed upon one another. In this case said second support surface is a mirror image of said first support surface . It will be appreciated that there is a space created between said second support surface and said first support surface where they are in spaced apart disposition. The space is partially filled by said optical members, and the remainder of the space need not be filled. However, where said decorative sheet material is used, for example, as a building partition, it can be advantageous to fill the space with a filler material. The filler material may be a thermal insulation and/or an acoustic damping material, or any other material with desirable properties, such as fire resistance. BRIEF DESCRIPTION OF DRAWINGS Preferred embodiments of the invention are described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a perspective view of a sheet material in accordance with a first aspect of the present invention; Figure 2 is a cross-section along line 2-2 in Figure 1 ; Figure 3 is a perspective view of a sheet material in accordance with a second aspect of the present invention. Figure 4 is cross-section along the line 4-4 in Figure 3; Figure 5 is a perspective view of a sheet material in accordance with a third aspect of the present invention; Figure 6 is a cross-section along the line 6-6 in Figure 5 ; Figure 7 is a perspective view of a sheet material in accordance with a fourth aspect of the present invention; and Figure 8 is a cross-section along 8-8 in Figure 7. BEST MODE FOR CARRYING OUT THE INVENTION The decorative sheet material illustrated in Figures 1-8 is intended primarily for use as a building sheet material to construct partitions and wall claddings, however it may be used effectively in the manufacture of many items such as tables, bureaus, wall and ceiling lights, shelving, windows (window surrounds), doors (door surrounds), flooring, flooring mats, pool furniture, outdoor furniture, awnings, signage, displays, security doors and shower screens. If desired, back lighting may be incorporated behind the decorative sheet material, or natural lighting may be relied upon to create the optical effect with aesthetic appeal. With reference to Figure 1, it can be seen that sheet material 10 in accordance with the present invention comprises a first support surface 11 and a second support surface 12, the first support surface 11 and second support surface 12 being mirror images . Each of the first support surface 11 and second support surface 12 includes a plurality of perforations such as perforation 13 in first support surface 11 and perforation 14 in second support surface 12. Perforation 13 in first support surface 11 is in register with perforation 14 in second support surface 12. Perforation 13 includes a downwardly depending annular lip 16 and perforation 14 includes an upwardly depending annular lip 17. An optical member such as glass bead 15 rests against each of the annular lips 16, 17 and is sandwiched therebetween. It will be appreciated that each of the annular lips 16, 17 tapers inwardly, so the perforation defined by the annular lips is generally frusto-conical in shape. Each glass bead 15 is generally spherical in shape and is larger in diameter than either of perforations 13, 14, at least where they open at annular lips 16, 17. In view of this, the majority of the spherical glass bead protrudes downwardly from where it engage annular lip 16 of perforation 13, and upwardly from where it engages the annular lip 17 of perforation 14. A minor portion of the glass bead 15 in each case extends into the respective perforations in the opposite directions. Typically the glass beads 15 are coloured or translucent glass, and may be made from recycled glass or new glass . Plastics materials may also be used to manufacture the beads. It will be appreciated that glass beads of this type have substantial impact resistance, which is inherent in their shape, and in conjunction with the supports 11, 12 create a strong and secure sheet material which will resist impact whilst still allowing the transmission of light. Moreover, the arrangement creates a decorative effect, particularly where translucent or coloured beads are used, as well as contributing to lighting a room or space. In the embodiment shown in Figure 1, the first support surface 11 is secured to the second support surface 12 by a plurality of bolts, such as bolt 18. In construction of the sheet material 10, the glass beads 15 are placed on annular lip 17 of the perforation 14 in second support surface 12, and first support surface 11 is placed on top of the glass bead with the perforations in the first support surface in register with those in the second support surface. Thus, a sandwich structure such as shown in Figures 1 and 2 is produced. As best seen in Figure 2, a number of bolts such as bolt 18 are inserted in holes (not shown) drilled through both first support surface 11 and second support surface 12. Nut 19 is tightened on bolt 18, causing the annular lips 16, 17 to bear upon glass bead 15. In this embodiment of the invention, the tension created by tightening nut 19 on bolt 18 is the sole force holding glass beads 15 within perforations 13, 14, but they may be glued in position before tension is applied thereto if desired. A gasket of the like may be included to ensure a good seal but adequate seal is usually provided merely by the abutment of the glass bead 15 on the annular lips 16, 17. The beads 15 could also be forced into the perforations 13, 14 before tension is applied, and would be held there merely by the tightness of the fit until construction of the sheet material 10 is completed. It will be appreciated that, not only are the annular lips 16, 17 compatible with the shape of the bead 15, they also allow for fixing of the glass beads during construction of the sheet material 10, and have inherent structural strength which contributes to the overall strength of the sheet material. In the embodiments shown in Figures 1 and 2, the perforations 13, 14 are each arranged in a grid array. The effect is to create a symmetrical field of individual points of light, most of the light being transmitted through the glass beads but some being reflected from the surface of the glass beads or being scattered due to internal reflections within the beads. The beads 15 may be various colours, translucent or transparent. Where they are coloured, the effect will be to create an array of individual points of bright colour which may form a pattern. Alternatively, with non-coloured glass beads the effect would be to create an array of points of light, which may be diffuse, which arrangement is generally pleasing to the eye. Moreover, when used as a structural feature such as a wall, the sheet material admits light into a room or the like whilst creating an optical effect with aesthetic appeal to persons in that room. The sheet material 10 may be backlit to enhance a transmission of light therethrough. It will be appreciated that the unique effect created when the glass beads 15 are in a grid array is at least partially due to the overall effect created by a plurality of glass beads in close formation, since no one bead becomes the individual focus in such an array. Each of the beads becomes a part of the surface within each pattern. Moreover, it will be appreciated that the spacing of the perforations in the pattern in which they are arranged will determine the nature of the optical effect created. The perforations 13, 14 can be spaced further apart if it is desired to have a high ratio of metal surface (where support surfaces 11, 12 are made of metal) visible or spaced closed together if it is desired to have more glass beads 15 present in the array. The invention can be practiced with recycled glass beads of low quality if desired, hence it is not expensive to construct. Moreover, the support surfaces 11,12 can be recycled metal or plastics materials if desired. With reference to Figures 3 and 4, the decorative sheet material 20 shown therein comprises a first support surface 21 and a second support surface 22. The first support surface includes a plurality of perforations, such as perforation 23, and the second support surface includes similar perforations, such as perforation 24, as best seen in Figure 4. The manner in which the glass beads 25 fit in the annular lips 26, 27 of the first and second support surfaces 21, 22, respectively is as described with reference to Figures 1 and 2. However, after construction of the sheet material 20, the space between the first support surface 21 and the second support surface 22, not occupied by beads 15, is filled with filler material 28 with insulation and acoustic damping material. Alternatively, a sheet of filler material 28 with perforations larger than the diameter of glass beads 15 formed therein is inserted between the support surfaces 21, 22 during construction. A suitable filler material is expanded polystyrene. The first support surface 21 and second support surface 22 can be bonded to the filler material 28 and may, optionally, be fixed to each other (not shown) . Alternatively, the first support surface 21 and second support surface 22 are secured to one another in any convenient manner without bonding to the filler material 28. It will be appreciated that any suitable insulating and/or acoustic damping material can be used as filler material 28. Alternatively, fire resistant material or other material with useful properties can be used to fill the space between first support surface 21 and second support surface 22. Nevertheless, it will be appreciated that the filler material 28 does not act to secure the beads 15 in position, they are secured as described previously with reference to Figures 1 and 2. At most, the glass beads 15 act as a spacer to maintain a desirable distance between the first support surface 21 and the second support surface 22 to allow it to be filled with a material with desirable properties. It will be appreciated that the spacer role for the glass beads 15, even in the absence of a filler material with useful properties, serves to give the sheet material thickness, which is desirable when used as a building panel or the like. Figures 5 and 6 show a sheet material 30 comprising a first support surface 31 and a second support surface 23. First support surface 31 includes a plurality of perforations, such as perforation 33, and the second support surface 32 includes a plurality of perforations, such as perforation 34. These perforations are in register, and receive an optical member, such as glass bead 35. The manner in which glass bead 35 is received is the converse to that illustrated in Figures 1 to 4. In this embodiment of the invention, the first support surface 31 and second support surface 32 are mirror images but are orientated in the opposite configuration to the first support surface 11 and second support surface 12 shown in Figure 1. Thus, the annular lip 36 around perforation 33 on first support surface 31 is an upwardly depending annular lip, whereas the annular lip 16 surrounding perforation 13 on first support surface 11 in the embodiment shown in Figure 1 is a downwardly depending annular lip. Moreover, the annular lip 37 formed around perforation 34 on second support surface 32 is a downwardly depending lip in the embodiment shown in Figure 6, whereas the annular lip 17 formed around perforation 14 on second support surface 12 in the embodiment shown in Figure 1 is an upwardly depending annular lip. Each of the annular lips 36, 37 is generally frusto-conical in shape and the glass bead 35 is larger in diameter than perforations 33 and 34. Accordingly, glass bead 35 rests comfortably in annular lips 36, 37 with a substantial area of contact between the two surfaces, which ensures a good seal is formed. A minor portion of the glass bead 35 extends through each of the perforations 33, 34 beyond the first support surface 31 and second support surface 32, respectively. Accordingly, incident light from within a room or interior of a structure may contribute significantly to the decorative effect. For example, incident light may be reflected or defracted by the optical member, or internal reflections of the incident light may scatter the light. Moreover, this effect can be enhanced where the optical member used is not entirely spherical, for example, if it has a projection extending further into the interior of the structure. In constructing a sheet material in accordance with the embodiment of Figure 6, glass beads 35 are positioned in the perforations, such as perforation 37 in second support surface 32. The glass beads may be fixed in said perforations by adhesive or may rest in the perforations under gravity. The glass beads could also be secured therein by the tightness of the fit or any other suitable means. First support surface 31 is positioned so that the perforations, such as perforation 33, are in register with the perforations in second support surface 32. The assembly is then created by allowing first support surface 31 to rest in the position shown on the glass beads 35. In this manner glass beads 35 serve to space the first support surface 31 and the second support surface 32. Once in position, a plurality of bolts, such as bolt 38, are positioned in holes (not shown) drilled in the support surfaces 31, 32. The nuts, such as nut 31, are tightened to clamp the support surfaces 31, 32 against the glass bead 35. Although nut 38 and bolt 39 are used in this embodiment of the invention, it will be appreciated that any convenient means of applying clamping pressure, or otherwise securing the first support surface 31 and second support surface 32 in the configuration shown can be used. A further embodiment of the invention is shown in Figures 7 and 8. In this embodiment of the invention, a sheet material 40 comprises a support surface 41 including a plurality of perforations, such as perforation 42. Each of the perforations has an annular lip, such as annular lip 43 which is downwardly depending lip, as the sheet material is orientated in Figures 7 and 8. The perforation 43 receives an optical member, in this case glass bead 44, and the glass bead 44 is secured in the perforation 42 by any convenient means, in the particular embodiment shown, the glass bead 44 is secured in the perforation 42 by adhesive, but it may be held in the perforation simply by the tightness of the fit, or a gasket may be included to ensure a tight seal. Any other means of fixing the glass bead 44 in the perforation 42 can be used. As best seen in Figure 8, the glass bead 44 in this embodiment of the invention is generally dome-shaped. The dome-shaped glass bead 44 has a curved surface 45 disposed to one side of the support surface 41 and extending substantially above the surface, and a flattened surface 46 disposed to the other side of the support surface 41 and extending substantially beyond that surface. An elongated side 47 abuts the annular lip 43 and can be secured thereto. However, it will be appreciated that by pushing the glass bead 44 upwardly, when the sheet material 40 is in the orientation shown, one can force it into the perforation 42 to a point where it will be held therein merely by the tightness of the fit. Since the glass bead 44 protrudes beyond the support surface 41, a special lighting effect is created. On the side of the support surface 41, through which curved surface 45 projects, there is a large surface area of glass and this increased the emphasis on the glass beads 44 over the support surface 41, thereby enhancing the aesthetic effect of the sheet material. It will be appreciated that this also allows the opportunity for instant light from within a structure to be reflected and/or diffracted, and also increased the opportunity for internal reflections. INDUSTRIAL APPLICABILITY Sheet material in accordance with the present invention is useful in the construction of a wide variety of items to give them enhanced aesthetic appeal .

Claims: CLAIMS 1. A sheet material for use in construction, comprising a first support surface including a plurality of perforations arranged in a predetermined pattern and a plurality of optical members, each said optical member being received in one said perforation. 2. A sheet material as claimed in claim 1 wherein each said perforation has a raised annular lip adapted to received said optical member. 3. A sheet material as claimed in claim 2 wherein each said optical member is secured in the desired perforation with adhesive applied to said raised annular lid. 4. A sheet material as claimed in any one of claims 1 to 3 wherein each said optical member protrudes from said first support surface in at least a first direction. 5. A sheet material as claimed in claim 4 wherein said optical member is generally spherical in shape. 6. A sheet material as claimed in claim 4 wherein said optical member also protrudes from said first support surface in a second direction, opposite to said first direction. 7. A sheet material as claimed in claim 6 wherein said optical member is generally dome-shaped. 8. A sheet material wherein said optical member is larger than said perforations . . A sheet material as claimed in any one of claims 1 to 7 wherein said perforations are arranged in a grid array . 10. A sheet material as claimed in any one of claims 1 to 9 wherein said optical member is made of a translucent or coloured material. 11. A sheet material as claimed in claim 10 wherein said optical member is a glass bead. 12. A sheet material as claimed in any one of claims 1 to 11, further comprising a second support surface including a plurality of perforations in register with the perforations in said first support surface, whereby each said optical member is received in one said perforation in each of said first and second support surfaces. 13. A sheet material as claimed in claim 12 wherein said second support surface is secured to said first support surface in spaced apart disposition. 14. A sheet material as claimed in claim 13 wherein said optical members are clamped between said first support surface and said second support surface. 15. A sheet material as claimed in any one of claims 12 to 14 wherein said second support surface is a mirror image of said first support surface. 16. A sheet material as claimed in any one of claims 12 to 15, further comprising a filler material disposed between said first support surface and said second support surface . 17. A sheet material as claimed in claim 16 wherein said filler material is a thermal insulation and/or acoustic damping material .

Inventors: RUBINSTEIN LEON DONALD, RUBINSTEIN, LEON, DONALD
Applicants: RUBINSTEIN LEON DONALD, RUBINSTEIN, LEON, DONALD
Application year: 1997
Main classification: E04C2
IPC codes: B44C5, E04C1, E04C2