INSULATING GLASS UNIT

Abstract

An insulating glass unit is provided. The insulating glass unit comprises two glass panes spaced apart by a transparent spacer material adherent to the glass panes, e.g. a silicone hot melt material. Optionally, an inert or heavy gas is trapped within the unit. The insulating glass unit further comprises a layer of a transparent silicone elastomer located at the periphery of the unit between edge portions of the glass panes and in contact with external surfaces of the spacer. Processes for making the insulating glass unit are also described herein.

Claims

1. An insulating glass unit comprising: two glass panes spaced apart by a transparent spacer material adherent to the glass panes; optionally, an inert or heavy gas trapped within the unit; and a layer of a transparent silicone elastomer located at the periphery of the unit between edge portions of the glass panes and in contact with external surfaces of the spacer.

2. The insulating glass unit as claimed in claim 1, wherein the spacer is adhered directly to the surface of the glass.

3. The insulating glass unit as claimed in claim 1, wherein the spacer is selected from the group consisting of glass, a hydrosilylation cured silicone rubber elastomer, a peroxide cured silicone rubber elastomer, clear butyl, polymethylmethacrylate (PMMA), polycarbonate, and extruded transparent polyisobutylene (PIB).

4. The insulating glass unit as claimed in claim 1, wherein the spacer is either self-adhesive to the substrate or adhered to the glass using a transparent primary sealant.

5. The insulating glass unit as claimed in claim 1, wherein the silicone elastomer is a cured elastomeric product of a moisture-curable hot melt silicone adhesive composition.

6. The insulating glass unit as claimed in claim 5, wherein the moisture-curable hot melt silicone adhesive composition comprises: (A) a reactive resin comprising the reaction product of a reaction of: (i) an alkenyl-functional siloxane resin comprising R.sub.3SiO.sub.1/2 units and SiO.sub.4/2 units, wherein each R is independently a monovalent hydrocarbon radical having 1 to 6 carbon atoms with the proviso that at least one R is an alkenyl radical, wherein the molar ratio of the R.sub.3SiO.sub.1/2 units to SiO.sub.4/2 units has a value of from 0.5/1 to 1.5/1, (ii) an alkoxysilane-functional organosiloxane compound having at least one silicon-bonded hydrogen atom, and optionally (iii) an endcapper, and optionally (iv) an alkenyltrialkoxysilane, in the presence of a (v) hydrosilylation catalyst; (B) a reactive polymer comprising the reaction product of a reaction of: (vi) an alkoxysilane-functional organosiloxane compound having at least one silicon-bonded hydrogen atom, and (vii) a polyorganosiloxane having an average, per molecule, of at least two aliphatically unsaturated organic groups, and optionally (viii) an alkenyltrialkoxysilane, in the presence of (ix) a hydrosilylation catalyst; (C) a moisture cure catalyst; and (D) a crosslinker.

7. A method of making insulated glazing units in accordance with claim 1, the method comprising: providing a first pane of glass having a first major surface; applying a transparent spacer onto the first major surface of the first pane; positioning a second glass pane having a first major surface on the transparent spacer; filling a cavity around the periphery of the glass panes with a transparent silicone adhesive composition, the cavity defined by the first major surfaces of the two glass panes and external surface of the transparent spacer; and curing the transparent silicone adhesive composition to bond the two glass panes and form an insulated glazing unit.

8. A method for making an insulating glass unit in accordance with claim 1, the method comprising: providing between the two glass panes an endless strip of transparent thermoplastics material in a plastic state applied as a hot melt, optionally containing a dehydrating material; urging the two glass panes towards each other against the thermoplastics material to form a spacer comprising the thermoplastics material adherent to the panes; optionally, introducing to the cavity defined by the two panes and the spacer an inert or heavy gas; and applying a layer of transparent silicone adhesive composition at the periphery of the unit in contact with external surfaces of the spacer.

9. The method in accordance with claim 7, wherein the transparent silicone adhesive composition is a moisture-curable hot melt silicone adhesive composition.

10. The method in accordance with claim 9, wherein the moisture-curable hot melt silicone adhesive composition comprises: (A) a reactive resin comprising the reaction product of a reaction of: (i) an alkenyl-functional siloxane resin comprising R.sub.3SiO.sub.1/2 units and SiO.sub.4/2 units, wherein each R is independently a monovalent hydrocarbon radical having 1 to 6 carbon atoms with the proviso that at least one R is an alkenyl radical, wherein the molar ratio of the R.sub.3SiO.sub.1/2 units to SiO.sub.4/2 units has a value of from 0.5/1 to 1.5/1, (ii) an alkoxysilane-functional organosiloxane compound having at least one silicon-bonded hydrogen atom, and optionally (iii) an endcapper, and optionally (iv) an alkenyltrialkoxysilane, in the presence of a (v) hydrosilylation catalyst; (B) a reactive polymer comprising the reaction product of a reaction of: (vi) an alkoxysilane-functional organosiloxane compound having at least one silicon-bonded hydrogen atom, and (vii) a polyorganosiloxane having an average, per molecule, of at least two aliphatically unsaturated organic groups, and optionally (viii) an alkenyltrialkoxysilane, in the presence of (ix) a hydrosilylation catalyst; (E) a moisture cure catalyst; and (F) a crosslinker.

11. The insulating glass unit as claimed in claim 1, wherein gas is trapped within the unit and comprises or consists of SF.sub.6 or an inert gas.

12. The method according to claim 7, wherein the silicone elastomer is applied with a minimum average thickness of about 3 mm measured in a direction parallel to the plane of the glass pane and such that it is in continuous contact with each glass pane.

13. The insulating glass unit as claimed in claim 1, wherein the spacer is adhered to the surface of the glass via a transparent primary sealant.

14. The method in accordance with claim 8, wherein the transparent silicone adhesive composition is a moisture-curable hot melt silicone adhesive composition.

15. The method in accordance with claim 14, wherein the moisture-curable hot melt silicone adhesive composition comprises: (A) a reactive resin comprising the reaction product of a reaction of: (i) an alkenyl-functional siloxane resin comprising R.sub.3SiO.sub.1/2 units and SiO.sub.4/2 units, wherein each R is independently a monovalent hydrocarbon radical having 1 to 6 carbon atoms with the proviso that at least one R is an alkenyl radical, wherein the molar ratio of the R.sub.3SiO.sub.1/2 units to SiO.sub.4/2 units has a value of from 0.5/1 to 1.5/1, (ii) an alkoxysilane-functional organosiloxane compound having at least one silicon-bonded hydrogen atom, and optionally (iii) an endcapper, and optionally (iv) an alkenyltrialkoxysilane, in the presence of a (v) hydrosilylation catalyst; (B) a reactive polymer comprising the reaction product of a reaction of: (vi) an alkoxysilane-functional organosiloxane compound having at least one silicon-bonded hydrogen atom, and (vii) a polyorganosiloxane having an average, per molecule, of at least two aliphatically unsaturated organic groups, and optionally (viii) an alkenyltrialkoxysilane, in the presence of (ix) a hydrosilylation catalyst; (C) a moisture cure catalyst; and (D) a crosslinker.

16. The method according to claim 8, wherein the silicone elastomer is applied with a minimum average thickness of about 3 mm measured in a direction parallel to the plane of the glass pane and such that it is in continuous contact with each glass pane.

Description

[0071] The following Examples, in which the parts and percentages are expressed by weight, illustrate the invention. Examples are to be read with the accompanying drawings in which

[0072] FIG. 1 is a diagrammatic section view through an insulating glass unit and

[0073] FIG. 2 is a diagrammatic section of an alternative insulating glass unit, both are illustrative of the invention.

[0074] The insulating glass unit shown in FIG. 1 was made by procuring a rectangular frame (10) of uniform section formed from hollow, square section of a transparent e.g. glass, tube, which was manufactured by bending all four corners on special bending equipment and joining the spacer frame along one of the longer sections by use of a connection (not shown). The frame may be perforated on the side to be directed to the interior of the unit and desiccant may be housed within the tube. The frame was used to provide a spacer secured to peripheral portions of two glass panes (12) and (14) by means of continuous deposits (16, 18) of a transparent primary sealant material e.g. a polyisobutylene based adhesive composition. A secondary seal (20) was formed around the edge of the unit by extruding the hot melt curable silicone composition as hereinbefore described into the U shaped space formed between the edges of the glass panes and the spacer. The composition was allowed to cure to provide the seal. Argon gas was introduced to the cavity (22) between the panes.

[0075] Alternatively in FIG. 2, a transparent thermoplastic material containing desiccant was heated and applied as a hot paste at a temperature in the range of about 120 C. to about 160 C. to the periphery of a cleaned glass pane (42) to form an endless tape (40) adjacent to but spaced from the extreme edge of the pane. Whilst the tape was still hot, another cleaned glass pane (44) was pressed against it. A gas e.g. argon may be introduced into the cavity (48), if required, typically at a slight over pressure and the panes were pressed together to squeeze the paste into a desired shape having a thickness of about 8 mm measured in a direction parallel to the plane of the glass pane and continuous contact with each glass pane over an area of 12 mm wide around the entire pane i.e. measured in a direction normal to the plane of the glass pane. The unit was allowed to cool to room temperature and the transparent thermoplastic spacer material 40 allowed to harden to provide the spacer bonded to both panes. Before the cooling had been completed a layer of the transparent silicone adhesive composition, preferably a moisture-curable hot melt silicone adhesive composition as hereinbefore described was extruded into the U shaped space defined by the spacer and peripheral portions of the glass panes and allowed to cure to form a seal (46) around the edge of the unit on top of the spacer and adherent to the panes of glass. The silicone seal had a thickness of about 3-4 mm measured in a direction parallel to the plane of the glass pane and was in continuous contact with each glass pane.

[0076] Tests have indicated that the water vapour transmission rate of the hot melt silicone adhesive according to EN 1279-4 gave an average permeability of 14.9 g/24 h.Math.m.sup.2 on 2 mm thick membranes. An example of an insulating glass unit using a transparent system as hereinbefore described is depicted in FIG. 3.