AU658088B2 - Improved insulation - Google Patents

Description

FR.

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AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT Name of Applicant: Actual Inventor: Address for Service: Invention Title: UNIONKRAFT PTY. LTD.

ALAN TRODDEN CULLEN CO., Patent Trade Mark Attorneys, 24L Queen Street, Brisbane, Qld. 4000, Australia.

IMPROVED INSULATION This is a divisional application made pursuant to the provisions of Section 39 of the Patents Act 1990 in respect of app.lication no. 29822/92.

The following statement is a full description of this invention, including the best method of performing it known to us: THIS INVENTION relates to improved insulation for buildings. More specifically, the invention is directed to an improved batt.

It is known to use batts in ceilings for insulation purposes. Typically, such batts are in the form of rectangular slabs of loosely matted glass fibres.

The fibreglass batts are dimensioned or cut to fit between the joists in the ceiling, and are laid on top of the ceiling, between the joists. The fibreglass material, or more correctly the air entrapped between the glass fibres, acts as an insulating layer between the ceiling and the roof, helping to reduce heat flow through the ceiling.

However, fibreglass batts have a major inherent 15 disadvantage. Namely, the thin glass fibres fracture easily and small fragments of glass fibres can become airborne and inhaled, thereby posing a serious risk to pe :sons handling the fibreglass batts. The glass fibres also irritate the skin. For this reason, persons who 20 handle fibreglass batts are required to use gloves, oe protective clothing and breathing masks.

Although the fibreglass batts are normally installed in the closed spaced between ceiling and roof or within walls, the small fragments of glass fibres are easily airborne and can find their way into other parts of the building. Fibreglass batts are therefore likely to pose a health risk for the inhabitants of the building in which the fibreglass batts are installed.

The insulating effect of fibreglass batts is due largely to the air trapped between the thin glass filaments. It is known that air is a good insulator.

The degree of thermal insulation can be increased by increasing the thickness of the fibreglass batt.

However, increasing the thickness of the batt also increases the amount of fibreglass material required, and hence the cost of the batt.

In an attempt to overcome the problems associated with fibreglass batts, it has been proposed to 3 use reflective insulation batts of the type described in Australian patent no. 511833. Such batts comprise two spaced-apart reflective layers, the air trapped between the layers forming an insulating layer. The reflective batts are laid transversely across the top of the ceiling joists so as to be spaced from the ceiling itself. In this manner, the air between the ceiling and the reflective batts acts as a further insulating layer.

However, the reflective batts also possess certain disadvantages. For example, as the batts are laid across the joists, they conceal the location of the joists, thereby making it very difficult for builders and tradesmen to move around on the ceiling.

Furthermore, the two outer reflective layers of 15 each batt are spaced apart by web portions hinged thereto. The batts are normally purchased in a flat, closed form in which the two layers are juxtaposed faceto-face, and then moved transversely relative to each other to pivot the web portions and thereby space the 20 layers apart. If excess weight is placed on the layers however, or if the layers are moved transversely in the opposite direction, the layers may once again return to the juxtaposed face-to-face configuration, rendering them largely ineffective for insulating purposes.

It is an object of the present invention to provide an improved insulating batt which overcomes or ameliorates the abovedescribed disadvantages of known batts, or which at least provides the consumer with a useful choice.

In one broad form, the present invention provides improved insulation comprising a relatively low density slab or layer of polymeric material hving a reflective sheet member bonded on at least one major face thereof.

Typically, the slab or layer of polymeric material comprises a loose knit mass of thin or fisat spun, non-woven, polyester fibres which may be carded to some degree to form a fibrillous or fleecy pile. The air

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trapped within the pile of polyester fibres acts as a thermal insulator. Further, as the polyester fibres are flexible, there is negligible risk that the fibres will fracture into small airborne fragments. Hence, the polyester fibre insulation material does not pose a health risk to persons installing the insulation, nor inhabitants of buildings in which the insulation is installed.

Typically, the insulation is in the form of batts, and a heat-reflective sheet is provided on both major faces of the batts. Each heat-reflective sheet may suitably comprise at least one layer of paper, coated or impregnated if desired with a bituminous or fire resistant material, and a reflective metallised film or foil over the outermost surface of the layer(s) of paper to reflect radiant heat. Each reflective sheet may be applied to a respective face of the slab of polyester *fibres by bonding with suitable adhesive.

The batt is suitably dimensioned, or cut on site, to fit between the ceiling joists or the wall studs of a building. When laid between the joists above a ceiling, the location of each joist remains readily identifiable, thereby enabling persons to walk easily along the joists of the ceiling.

In an alternative embodiment, a sheet having a reflective surface on both sides thereof is applied to only one major face of the slab of polyester fibres.

This particular form of insulation is particularly suitable for wrapping around air conditioning ducts and other conduits which are to be thermally insulated. This alternative embodiment is also suitable for use under iron roofs or between a raked ceiling and its adjacent roof.

In order that the invention may be more fully understood and put into practice, a preferred embodiment thereof will now be described by way of example only.

In one preferred embodiment, the invention comprises a rectangular slab formed by a loosely packed, non-woven, fibrillous or fleecy pile of thin polyester fibres. However, any other suitable polymeric fibre material may be used. The thinly spun polyester fibres may be at least partially carded to form a roughly stratified fleecy pile. The fleecy pile is spongy and may therefore be compressed for packing and distribution.

The flexible polyester fibres are not susceptible to fracturing, and therefore unlikely to pose any health risk.

Top and bottom reflective sheets are glued to the major faces of the polyester fibre slab. Each reflective sheet member typically comprises at least one layer of paper coated on the outside thereof with a metallised film or foil. The layer(s) of paper may be 15 coated or impregnated with a fire retardant, if desired.

•go e In an alternative embodiment, a reflective sheet is applied to only one major face of the polyester fibre slab. This embodiment is suitable for use in applications in which the non-reflective side of the slab 20 is not subjected to radiant heat to any substantial ooeo degr-e.

The foregoing describes only some embodiments of the invention, and modifications which are obvious to those skilled in the art may be made thereto without departing from the scope of the invention as defined in the following claims.

oo o For example, insulation comprising a continuous layer of fleecy polyester fibre pile having a single reflective sheet on the outer side thereof may be applied around ducts or other conduits, under iron roofs, or between raked ceilings and tiled roofs.

Claims (8)

1. Insulation comprising a relatively low density slab or layer of fibrous polymeric material, having a reflective sheet bonded to at least one major face thereof.

2. Insulation as claimed in claim 1, wherein the polymeric material comprises a fleecy pile of thin non- woven polyester fibres.

3. Insulation as claimed in claim 1 or 2, wherein a reflective sheet is bonded to both major faces of the slab or layer of polymeric material.

4. Insulation as claimed in any one of claims 1 to 3, wherein each reflective sheet comprises a layer of paper material having a reflective metallised layer 15 bonded thereto.

5. Insulation as claimed in any one of claims 1 to 4, wherein said insulation is in the form of one or more batts.

6. Insulation as claimed in claim 1 or 2, wherein the reflective sheet is bonded to only one major face of the slab or layer of polymeric material

7. Insulation as claimed in claim 6 wherein the sheet has reflective metallised layers on both sides thereof.

8. An insulation batt substantially as hereinbefore described. DATED this sixteenth day of February 1994 UNIONKRAFT PTY. LTD. By their Patent Attorneys CULLEN CO. ABSTRACT An insulation batt (10) comprises a layer of thin non- woven polyester fibres carded to form a fleecy pile (13). Reflective sheets (14) are adhered to the top and bottom faces of the polyester layer The flexible polyester fibres of the batts (10) are less susceptible to fracturing than the glass fibres of conventional batts. 00. Ilr