Related Application

This application is a continuation-in-part of U.S. Application Serial No. 10/675.044. filed 09/30/2003.

Field of the Invention

The present invention relates to a system for fastening or securing frangible or brittle materials to a supporting structure. More particularly, there is provided a system for fastening brittle material such as glass, ceramic, plastic, etc. so as to prevent stress cracking and to the laminates formed.

Description of the Prior Art

Non-elastic materials (brittle materials) such as ceramics, glass, and more brittle plastics such as polycarbonate and acrylics perform well in compression but do not have good performance in tension particularly over time. When it is preferred to attach sheets of these materials such as glass and ceramics to a supporting structure with just bolts or pins of some sort, the penetration of these bolts or pins through the brittle sheet cause stress points and are subject to cracking. In addition, if the panel is decorative or is armor, it is preferred not to have any holes bored through the brittle sheet.

When using brittle sheets such as glass and ceramics, it is very desirable to not have any penetrations to the outside panels whether the panel is transparent, does decorative structural use for ballistic armor as in laminated transparencies, in

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windshields, and/or the like. Penetrations through the brittle sheet cause a weakening, a point of possible failure and loss of artistic and aesthetic value where applicable.

Various technological arrangements are known for mounting glazing units to provide the aesthetical and architectural benefits of continuous glazed facades which are typically fixed on high rise buildings. Generally the glazed facade assembly in the form of glass or ceramic panels or units is mechanically secured to a substructure of the faςade. The substructure is mounted on the outside of a load bearing building skeleton of metal or reinforced concrete. However, the means for mechanical fastening for this purpose involves some projecting parts and/or providing fastening holes through the layers of glass or ceramic which distort the outer surface of the panels and/or stresses about the holes.

In an attempt to obtain the desired smooth outer surface of the faςade form wherein no parts are projecting and the individual glass units remain integral, the glass panes were mounted exclusively by means of adhesive bonding. For safety reasons, building authorities have not generally permitted such facades without positive locking. Moreover, the prior art methods are limited to certain thickness of the facade.

The current practice in faςade construction is described in U.S. Patent No. 4,481,868 to McCann, which is incorporated herein by reference, discloses mechanically fastening sections of glass panels to the supports of a building. That patented glass assembly comprises a planar array of sealed multiple glazing units each comprising two opposed spaced sheets with a seal between the sheets defining a sealed gas space, which units are secured to supporting members with the outer surface of the units sealed edge-

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to-edge, at least some of the units being secured to the supporting members by a mechanical fixing passing through the outer sheets of the units outside the seals of the units. In a preferred embodiment, each unit is a multiple glazing unit which is secured to the supporting member by bolts whose heads are countersunk into holes countersunk in the outer face of the unit outside of the seal of the unit. The outer surface of the outside sheet of the glazing unit is protected against destructive stress cracks by cushioning and bushings and washers placed between the bolt and the glazing surfaces. The bushings and washers prevent glass-to-metal contact and prevent damage to the glazing sheets.

There are several disadvantages in the patented glass assembly directed to aesthetics and the manner of assembly. The holes required to accommodate the attaching bolts weaken the entire unit, destroy the integrity and smooth surface of the outer panel. The flat headed bolts even if countersunk into the glass detract from the uninterrupted planar appearance of the outside of the assembly. The necessity to carefully drill through multiple layers of glass and align these pieces constitutes a difficult and costly manufacturing problem. The drilling of glass to produce a countersunk hole usually requires two steps and may entail considerable glass breakage. Likewise, if the holes are not properly aligned, during assembly of the facade the tightening procedure will result in breakage resulting in down time and material loss.

The McCann patent does not disclose any laminated structure. The critical feature of the present invention is a glazing unit having embedded in a polymer polymer layer a mechanical securing element.

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It is known in U.S. Patent No. 2,310,402 to Dennison, which is incorporated herein by reference, to provide a glass insulation unit of a glass laminate wherein a metal border is embedded in plastic interlayers.

U.S. Patent No. 4,029,942 to Levin, which is incorporated herein by reference, discloses bus bars embedded in transparent laminates to provide electrical contacts to heat windows for defrosting and defogging.

U.S. Patent No. 4,799,346 to Bolton and Smith, which is incorporated herein by reference, discloses an attachment member mounting embedded in a transparent resinous layer of a laminating glazing unit. The attachment member mounting is fastened to a frame or support structure by bolting or clamping. In a preferred embodiment a resistance means for preventing removal of the mounting is in form of protrusions which extend from the plane of the member on that portion which is embedded within the interlayer. Among the resins suitable for use as interlayers for the laminate are mentioned ionomer resins.

The present case distinguishes from the Bolton and Smith patent in that the present invention is a unit integrated with a mechanical securing element which eliminates the need for the attachment mounting element of the patent.

Summary of the Invention

According to the present invention, a system for securing frangible or brittle material as a supporting structure wherein said system has at least one mechanical securing element embedded within a rigid polymer layer, preferably an ionomer, bonded

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to at least one monolithic element to provide an integrated mounting system enabling such units to be fixed to a support without disruption or distortion of the monolithic structure of the element. A plurality of laminated units are capable of being mounted in a planar array on the inner or outer surface of a building having a concealed framework to produce a continuous glazed facade on the outside or a wall surface on the interior.

In its broadest aspect the present invention relates to a novel laminate unit comprising: at least one monolithic element bonded to at least one rigid polymeric layer having embedded therein a mechanical securing element selected from male or female interactive fastening means, screw or pin. Either the male or the female securing element can be embedded in the polymer. The invention is applicable to any construction ranging from single laminates and/or multiple panes.

When a laminated multiple unit such as a double glazing unit is involved, a hole or slot is formed in the internal glazing element to accommodate the stem of a male securing element. In a glazing facade assembly procedure the male stem of a male- female interactive fastening means is aligned with and passes through a hole or slot in a support structure regardless which securing element is embedded.

The external and/or internal sheets may be any well known commercial tile, plate, float or sheet glass or plastic composition. Plastics which are well known in the plastics art such as polycarbonate polymers may be used either alone or in combination with glass glazing or with other plastics. An ionomer copolymer forms excellent strong bonds with glass, metals and plastic materials.

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The polymers useful in this invention for forming a bonding layer or laminate interlayer and embedding a mechanical securing element are those capable of providing the high tensile strength necessary to support multiple brittle units. Furthermore, the ionomer copolymer layer maintains the integrity of the units when they are subjected to physical impact or thermal stress.

It has been found that ionically crosslinked copolymers of ethylene-methaerylic or acrylic acid or ethylene-methaerylic or acrylic-acid-polyamine provides the toughness, high clarity, and superior tensile strength, which are most useful. The ionomers can be unneutralized or partially neutralized with an alkali metal cation.

The mechanical securing element which is embedded within the plastic layer may be any male-female coacting mechanical fastening means. As mentioned above, either the male or the female securing elements can be embedded. The mechanical securing elements in combination are a means for securing the laminate to a supporting frame or other load bearing structure. Preferably, a bolt and nut provides a mechanical connection by simply screw-tightening the laminate against the supporting structure. Other mechanical securing combinations include snap together couplings, clamps, and the like or pins, bolts and screws.

A compressible and/or flexible material may be interposed at metal to glass or ceramic or metal to plastic interfaces in the form of bushings, gaskets, sleeves, seals, or washers.

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It is the primary object of the present invention to provide a laminate having brittle elements with means for securing the glazing unit to a frame or other structural support.

Another object of this invention is to improve the integrity of the laminate in the frame or structural support when subjected to high physical impact or thermal stress.

A further object of this invention is to ensure a safe retention of the laminate in position even in case of the breakage or cracking of the brittle element.

A still further object of this invention is that the laminate secured in the manner disclosed appears devoid of any projection or visible fixing element.

Yet another object of this invention is to provide a plurality of an improved ceramic glazing unit for producing a planar array on a building exterior or interior having an uninterrupted surface, uniformity and continuity in reflection and color.

Still yet another object of the invention is to provide a laminate for the fixed windows of automobiles and aircraft such as windshields and canopies.

Other objects and a fuller understanding of the invention will be had by referring to the following description and claims of a preferred embodiment, taken in conjunction with the accompanying drawings, wherein like reference characters refer to similar parts throughout the several views.

Brief Description of the Drawings

Fig. 1 is a cross-sectional view of a single glazing unit having a male mechanical securing element, a bolt head, embedded in a bonded ionomer copolymer layer.

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Fig. 2 is a cross-sectional view of a double glazing unit having a female mechanical securing element, a capped nut, embedded in the bonded ionomer copolymer layer.

Fig. 3 shows a sectional view of a plurality of the laminated glazing units 20 as illustrated in Fig. 2 forming a glazing assembly of planar rectangular panels.

Fig. 4 is a cross-sectional view of a double laminate having a female securing element in the form of a flange and stud.

Fig. 4A is a cross sectional view along line y-y of Fig. 4.

Fig. 5 is a cross-sectional view of a unit used for hanging pictures or panels.

Fig. 6 is a cross-sectional view of a laminate having multiple brittle panels.

Description of the Preferred Embodiments

According to the invention there is provided a simple fastening and support system for fastening and securing frangible or brittle sheets, panels or tiles to a supporting structure. These frangible or brittle units can comprise glass, ceramic or polymeric such a polycarbonate or acrylic resins. Generally, the units are bonded or laminated to a thermoplastic such as an ionomer, polyurethane, polyvinyl alcohol or other adhering polymers whereby any load placed on the outer brittle or frangible unit is directly transferred to the strongly adhering thermoplastic. The thermoplastic has bolts, screws or pins molded or embedded within it prior to lamination to the brittle or frangible unit. The shafts of the pins, screws or bolts are preferably perpendicular to the surface of the thermoplastic in the opposite direction from the side of the frangible or brittle unit

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and is laminated to the thermoplastic. The cap or end of the bolt, pin or screw which is embedded or molded within the thermoplastic is flared so as to provide a sufficient surface area of resistance to being pulled from the thermoplastic by the force exerted on the brittle or frangible unit. In effect, it is anchored within the thermoplastic with the pin, screw or bolt sticking out which provides the fastening point to the overall supporting structure or frame, cable, wire or rod. The head or cap of the pin, screw or bolt is sufficiently within the body of the thermoplastic so as not to cause strain or interaction with the adhesion interface or face of the frangible or brittle unit. The thermoplastic is of sufficient strength and thickness to provide a firm anchor to the pin, screw or bolt.

In cases where there is a sandwich lamination between two or more layers or sheets of brittle materials which are laminated together by means of one or more thermoplastic layers, the outer brittle layer is done as described previously. However, holes are drilled through the second (inside brittle layer) that are aligned with the perpendicular pins, screws, or bolts. The whole sandwich laminate can be laminated at one time. It is important to be sure that the aligned holes in the inside brittle layer are large enough so that the pins, screws, or bolts which pass through them do not touch the edges of the holes in these brittle sheets. As a further assurance, the pins, screws, or bolts can be sheathed in the laminating plastic or a grommet of some type placed around these pins, screws, or bolts to provide a good seal on laminating and to prevent contact with the brittle sheet edges. In this way, the inside laminated brittle sheet is also laminated to the thermoplastic layer which supports both of the brittle layers and which is in turn supported by the perpendicular pins, screws, or bolts which are fastened to the overall

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supporting members. In all of these construction laminates the outer brittle face is not penetrated by any bolt, screw, or pin and retains its maximum strength, aesthetic appearance and maximum impact resistance.

Referring to drawings Figs. 1 to 3 there are illustrated a novel single glazing unit, a laminated glazing unit and a glazing assembly according to his invention. A plurality of these glazing units when arranged in a planar array and mechanically secured to a concealed structural support member of a building form a glazing assembly having a monolithic facade with aesthetical and practical architectural benefits.

The simplest application of this invention as shown in Fig. 1 involves a single monolithic glazing unit 10 which comprises a monolithic external glazing element 11 such as a glass glazing having a smooth outer surface 11a and an inner surface lib bonded to an internal polymer layer 12 which is preferably an ionomer having surfaces 12a and 12b and embedded therein at least one male mechanical securing element 7 such as bolt 17. The bolt 17 comprises a fiat head 18 and a threaded stem 16. As shown in the figure, the flat head 18 is totally embedded within the polymer layer 12 in a fixed position with the threaded stem 16 projecting from the glazing unit 10. A female mechanical fixing element nut 19 is connected to the threaded stem 16 to form a mechanical securing assembly and enables the monolithic glazing unit to be secured to a structural support 14 (partially shown) by tightening the nut 19. The inherent properties of adhesive strength and high tensile strength of the polymer locks the flat head 18, increases the load bearing capacity of the mechanical securing assembly and accepts increased load bearing pressure.

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In practice the installation of the monolithic glazing unit 10 to a support structure 14 involves passing the threaded end 16 of the bolt 17 through a bushing 13 and circular hole 15 of support structure 14. The hole 15 has a diameter slightly larger than the threaded stem 16 to provide adequate clearance to compensate for the monolithic glazing unit 10 which is secured to the support structure 14 by tightening nut 19 on the threaded stem 16 at face 12b of the ionomer layer 12. The tightening action causes pressure to be distributed through the bushing 13. The bushing 13 is of sufficient size and elasticity to accommodate relative movements between the ionomer layer 12 and the structural support 14.

A plurality of the monolithic glazing units 10 may be employed in a planar array as a building facade or an interior ceiling and wall assembly in which each of the laminated glazing units are secured to a support structure by mechanical securing assembly wherein at least one element of the assembly is embedded in the polymer layer of the laminate.

The term "monolithic" as used herein relates to a glazing element to be integral, i.e., without holes or fragmentations.

In Fig. 2 there is shown a laminated multiple glazing unit, specifically a glass double glazing unit 20 comprising an external glass element 21 having an outer surface 21a and an inner surface 21b and an internal glass element 23 also having outer and inner surfaces 23a and 23b which are bonded together with polymer interlayer 22. The interlayer 22 has embedded therein a female securing element such as a capped nut 27. A circular fixing hole 24 is formed through the internal glass element 23 and has a diameter

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slightly larger than that of the mechanical fixing element 26. In this case the male fixing element is a bolt 26 comprising a head 25 and a threaded end which is sized to engage the embedded capped nut 27. As seen in Fig. 3, the laminated glazing assembly 30 (Fig. 2) is constructed from a plurality of laminate multiple glazing units. Each glazing unit has an uninterrupted outer surface which can be secured to a concealed supporting framework to provide an uninterrupted planar appearance of the outside of the assembly. Preferably, the multiple glazing unit is a laminated glass double glazing unit 20 as described in Fig. 2. This glazing unit 20 is integrated with the mechanical connection with bolt 26. The facade assembly procedure for attachment of each glazing unit 20 typically involves units having rectangular or square shapes with the mechanical securing element embedded in each corner. In this case the threaded end of bolt 26 is passed through hole 15 in support structure 14 through bushing 28 and through fixing hold 24 to connect with embedded capped nut 27.

After engaging the capped nut 27 the bolt head 25 is torqued to exert force on bushing 28 which distributes the pressure to the inner surface 28 which distributes the pressure to the inner surface 23b thus securing the glazing unit 20 to the support structure 14. Various arrangements of compressible elastomeric gaskets, washers, and seals in addition or in place of the bushing shown may be used to avoid glass-to-metal contact and prevent damage to the glazing sheets. Such arrangement and choice of compressible and/or flexible material is clearly known in the glazing art.

The critical feature of the invention resides in that at least one of the mechanical securing elements is embedded in an ionomer or polymer layer or interlayer. The

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mechanical securing assembly useful in this invention results from the interaction of male-female components either of which may be embedded in the ionomer layer without any consequence.

The terms "external" and "internal" as used herein refer to the position of these elements relative to the facade.

Fig. 3 illustrates a laminated glass double glazing assembly 30 comprising a planar array of laminated glass double glazing units 20 as shown in Fig. 2 each of which are mechanically secured at their respective corners to conceal support members 14 behind the array which are part of a structural framework to which the glazing assembly 30 is secured. The outer glass glazing surface 21a of the double glazing units 20 are positioned edge-to-edge so as to appear to be continuous. However, a small gap between adjacent edges can remain and this can be sealed with a silicone sealant as indicated at 31, if required.

It is understood that in each of Figs. 1 to 3, the glass may be replaced by a ceramic or plastic for use in exteriors or interiors of buildings.

Fig. 4 shows another embodiment of this invention in which a female mechanical securing element 50 as shown in Fig. 4A is embedded in the polymer layer 42. The construction of the securing element 50 involves a metal flange 49 attached to an internally threaded stud 48. Additionally the flange has a plurality of spaced apart circular holes 51. These holes provide additional surface areas for adhesion to the ionomer polymer layer 42. The laminated double glazing unit 40 comprises external ceramic or glass glazing element 41 and internal glazing element 43 bonded together with

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91

the polymer interlayer 42 having embedded therein the female securing element 50. A bolt 45 having a threaded end provides the necessary male securing element. The bolt head 44 is torqued to tighten the glazing unit for attachment to a support structure 14. In this construction the weight of the glazing unit is borne by the polymer layer 42. Preferably, the flange and stud are welded together and employ stainless steel as the material of construction.

Fig. 5 illustrates a laminate 55 which is suitable for use with hanging pictures or in connection with panels or tiles for the interior of a building. A polymer sheet 57a has imbedded an upwardly directed pin or screw 58 with a portion extending beyond the sheet surface to act as a hanging hook. The screw or pin 58 has an enlarged head within the polymer 57 and resistance protrusions 58a to prevent the removal of the screw or pin from the polymer 57a. Optionally, a hanging hook 61 is embedded in the rear wall for attachment to a wall support (not shown). A brittle element 56 such as a ceramic is laminated onto a polymer 57 having an inclined cavity 62 with a plug 59 having serrations 59a for connecting to the pin or screw 58, an adhesive layer 60 which is the face of either polymer 57 or 57a is used to attach the units together. The pin or screw 58 will then act as a bearing member to support the load.

The brittle element 56 can be laminated separately to polymer 57 by heat and pressure and then adhesively bonded onto polymer 57a.

As illustrated in Fig. 6, a laminate can be formed by laminating together a combination of a frangible sheet 71 such as glass or ceramic onto the surface of a polymer 72 and a further frangible sheet 75 is between polymers 72 and 73. Prior to

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lamination a cavity is formed in each of polymers 72, 73 and aligned with a hole 76 in which there is a grommet 77. A securing means 74 which can be a mechanical fastener, bolt or the like is embedded in each of polymers 72, 73 and passes through frangible sheet 75 surrounded by the grommet 77 to prevent cracking the brittle sheet 75.

According to the invention there is provided a method of fastening or securing frangible or brittle elements such as glass, ceramic brittle polymers such as polycarbonate onto polymeric sheets and supports to form glazing units, support panels for exteriors of buildings, form tiles for building interiors or the like without causing stress on the frangible or brittle elements. The invention provides adhering at least one rigid member in the polymer without having the frangible or brittle element supported on the rigid member. The rigid member is such that there would be a resistance to its removal from the polymer.

The material preferred for either external or internal elements may be any well known commercial tiles, plate, float or sheet compositions. A glass element may be tempered or non-tempered or chemically strengthened. Synthetic polymers to which the ionomer polymer resin provides good adhesion which includes polycarbonate resins, fused acrylic/polycarbonate resins, polyurethane, etc. The invention contemplates the use of one or more inner or outer layers of various polymer combinations. Preferably an inner layer is an ionomer layer and has embedded therein the mechanical securing element. The frangible or brittle material may range from transparent to opaque, may be tinted or deeply colored. Glazing material may include coatings which provide specific

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properties or special effects such as reflecting and non-reflecting properties, ultraviolet radiation absorbing, etc.

The thickness of the frangible or brittle element unit may vary from about 8 mm to 19 mm for the external unit and between about 5 to 15 mm for the internal unit. The thickness of the ionomer or polymer layer or interlayer will range from 3 to 60 mm. The good adhesion and the high tensile strength of the ionomer or polymer allows for multiple units in excess of three or more frangible elements. Further the thickness of each element may vary which allows for a wide latitude in unit design.

Thermoplastic interlayers usable in the invention must be capable of strongly bonding to a rigid panel such as glass to form an impact-dissipating layer, for example, in a laminated safety glass assembly. Exemplary thermoplastics include poly(ethyl-vinyl acetate), poly(ethylene-vinyl acetate-vinyl alcohol), poly(ethylene-methyl, methacrylate- acrylic acid), polyurethane, plasticized polyvinyl chloride, polyvinyl alcohol (PVA), polycarbonate, ethylene acrylic acid, polyethylene acrylic acid and partially or fully neutralized versions thereof etc. Polyvinyl butyral (PVB) and more particularly partial PVB containing about 10 to 30 weight % hydroxyl groups expressed as polyvinyl alcohol is preferred. Such partial PVB further comprises about 0 to 2.5 weight % acetate expressed as polyvinyl acetate with the balance being butyral, expressed as polyvinyl butyral. The non-critical thickness of the thermoplastic sheet can vary and is typically about 0.25 to 1.5 mm, preferably about 0.35 to 0.75 mm. PVB sheet is commercially available from Monosanto Company as Saflex ® sheet and E.I. Dupont de Nemours and Co. as Butacite ® polyvinyl butyral resin sheeting.

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Preferred interlayers are ionomers such as disclosed in U.S. Patent No. 5,763,062 and 4,663,228 which are herein incorporated by reference. Most preferable are the ionomers which have been at least partially neutralized with an alkali metal cation and a polyamine.

The mechanical securing assembly can be of a typical mechanical fastening means, besides the nut and bolt assembly mentioned above, various retention clamps, clips and means for snap together engagement are usable for this purpose. The glazing assembly is not only easy to install by virtue of the simple construction of the fixing means but the integrity of the external units is maintained so that continuous uninterrupted planar appearance of the outside assembly is provided. Suitable metals useful as materials for the mechanical securing assembly include aluminum and steel but preferably corrosion resistant materials such as stainless steel and high impact plastics including fiberglass and thermoset phenolic-aldhyde polymer and a polyamine.

Fixing inserts of compressable and/or flexible materials are used at metal-glazing material contact areas to prevent stress cracking as well as to improve impact resistance, compression for thermal expansion and to secure water-tightness. Fixing inserts of elastomeric material in form of bushings, gaskets, sleeves, spacers and washers are used in bolt-fixing insert, nut-fixing assembly systems. The specific securing assembly of the mechanical connection will vary depending on the size and design of the individual glazing units and the final facade design. The assemblies can also be used to hang picture frames.

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Example 1

A windshield is prepared by inserting a 3-4 mm interlayer of an ionomer (NOVIFLEX ® sold by AGP Plasties, Inc. of Trumbauersville, PA) between two sheets of glass of 10 mm thickness in which aligned holes are prebored partially in the ionomer and completely through the inside layer of the glass. A stainless steel stud having a tapered head with a standard 82 degree taper was inserted into the ionomer. The barrel of the stud is 20-25 mm in diameter and the head is tapped with a 9 mm coarse thread. A metal or plastic bushing is used to hold the inner glass layer in place. The assembly is placed in a so called "polymer" bag of the type disclosed in U.S. Patent No. 3,311,517 to Keslar et al. The bag comprises an outer ply of polyethylene terephthalate and an inner ply of polyethylene bonded thereto. The bag is inserted into a second bag evacuated and sealed. The unit is placed in an autoclave at 225 ⁰ F for three minutes under 150-200 psi pressure in a vacuum. The vacuum causes the ionomer to flow and seal the opening and set the bolt.

If required, a large washer or metal strip with plastic cushioning may be used to tighten the assembly and to provide further security in the event that the outer glass is broken. Depending upon the size and weight of the laminate several fastening means can be used.

Example 2

The preparation of a glassing unit similar to that described in Fig. 2 was conducted as follows:

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A cross-link partially neutralized ethylene-acrylic acid ionomer resin was added to the resin port of a small extruder having an extruding barrel temperature which was maintained at 165-205 ⁰ C. A film (50-60 mils) was extruded and cut into 12 squares of about 25.4 mm, stacked to about 13 mm thickness between two sheets of tempered glass one of which had a hole of 12 mm drilled in the center of the sheet. A 9 mm stainless steel capped nut was placed in the hole. The glazing unit was placed in a vacuum bag comprising an outer ply of polyethylene terephthalate and an inner ply of polyethylene bonded thereto. The bag was inserted into a second bag of the same material, evacuated and sealed. The sealed bag assembly was placed in an autoclave at 125 ⁰ C for three minutes under 150-200 psi in a vacuum. The autoclave was reduced in pressure and cooled to room temperature. The bag assembly was removed from the autoclave and plastic wrappings were removed from the glass unit. This procedure embedded and fixed bonded the capped nut. A 9 mm stainless steel bolt was connected and screwed into the fixed capped nut.

The glazing unit was then tested with tension applied at the head of the bolt. This indicated a strong adhesive bond of the ionomer polymer with the capped nut and a high tensile strength of the inherent in the ionomer layer.

It is intended that a use of the units constructed in accordance with the invention will be in the commercial glazing industry, particularly when flash glazing is required. In addition to this architectural glazing which can provide a desirable external appearance due to the uninterrupted planar array of an outside assembly, the glazing units

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can provide the same effect for a decorative interior wall or ceiling. The glazing units of this invention can be used for automobiles and other vehicles or as picture hangers. Multiple glazing units of this invention can be used in security glazing for banks, prisons, armored trucks, interior or exteriors of buildings.

It will be understood that the above-described embodiments of the invention are only for the purpose of illustration. Additional embodiments, modifications and improvements can be readily anticipated by those skilled in the art based on a reading and study of the present disclosure. Such additional embodiments, modifications and improvements may be fairly construed to be within the spirit, scope and purview of the invention as defined in the claims.

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