AU665532B2

AU665532B2 - Insulation pellets and a process for producing same

Info

Publication number: AU665532B2
Application number: AU15152/92A
Authority: AU
Inventors: Rolf Karl Hartelt
Original assignee: FLEXICOAT AUSTRALIA Pty Ltd
Current assignee: Enviroflex Pty Ltd
Priority date: 1991-04-26
Filing date: 1992-04-24
Publication date: 1996-01-11
Anticipated expiration: 2012-04-24
Also published as: AU1515292A

Description

i' II u rr~-u~ 6 5 5 3 2 P/00/0011 Regulation 3.2

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

a 0* 0* 1 t e*s o i Name of Applicant: FLEXICOAT AUSTRALIA PTY LTD Address for service in Australia: Invention Title: I

I

CARTER SMITH BEADLE, Qantas House, 2 Railway Parade, Camberwell, Victoria, 3124, Australia, Attorney Code SA.

NSULATION PELLETS AND A PROCESS PRODUCING SAME

FOR

Details of Associated Provisional Applications: Nos: PK 5884 The following statement is a full description of this invention, including the best method of performing it known to me/us.- 1 1- 1 i 2 This invention relates to insulation 'I 0 I 0400 O I D O i)

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materials.

In AU-B-82192/82 there is described a method of insulating the ceiling of a building, which comprised the steps of placing loose fill insulating material directly above the ceiling lining material to a desired thickness, applying a coating of liquid glue or adhesive to the surface of the insulating material remote from the lining material and allowing the glue or adhesive to dry or set forming a cohesive skin on the surface of the insulating material.

The method of AU-B-82192/82 has proved very satisfactory, particularly with the use of preferred materials such as cellulose fibre material for the loose fill insulating material, and diluted PVA glue for the liquid glue. However such a method, and the resulting in situ insulation, is only suitable for insulating ceilings, and it has become apparent that there is a need for a similarly effective insulation for the walls of buildings.

Presently available fibreglass insulation batts for walls are unsatisfactory, as they degrade over time. It has been found, for example, that after a period of from 5 to 7 years, fibreglass batts used in wall cavities disintegrate. The constituent fibres falls under the influence of gravity to the bottom of the cavity, leaving other portions of the cavity without any insulating material.

Furthermore, another serious consequence of such jcspe.027/flexi 92 4 24 -11 A batt disintegrations is that glass fibres of a length dangerous to human lung tissue are released, and may find their way into the living space of a dwelling or other building.

Other insulation materials have disadvantages.

Mineral wool (rockwool) batts are used in wall cavities, but the fibres (and the glass fibres from fibreglass batts) are recognised as being dangerous.

Installers are recommended to wear "full protective clothing including gloves and face mask" to "reduce oskin irritation" (Insulation Guide, Energy Information Centre, Victoria, May 1988).

Furthermore, foam insulation normally installed in situ by combining chemicals which are pumped from a gun into wall cavities is also unsatisfactory and possibly dangerous. Urea formaldehyde and Urethane °foams are two examples of foam insulation. Such foam insulation contains phenyl resins, which are now believed to contribute to the destruction of the ozone layer, and which are accordingly not likely to be used in the future. Polystyrene foam is also inflammable, and cannot be fire rated.

The loose fill insulation material of AU-B- <82192/82 may be installed in wall cavities, but the nature of the material means that over time, the material will compress under its own weight, leaving an upper portion of the cavity devoid of insulation material.

It is an object of this invention to provide an jcspe.027/flexi 9Z 4 24 pp. 1 4 improved insulation material for use in wall cavities.

In this specification, including the claims, the term 'loose fill cellulose fibre insulation material' is defined as cellulose fibre insulation material manufactured from newsprint which is pulverised into a fine fluff, and treated with a fire retardant.

Suitable fire retardants are borax or boracic acid.

A similar definition of loose fill cellulose fibre insulation material may be found in the booklet "Insulation Guide" published in May 1988 by the Energy Information Centre, Victoria.

The invention provides a method for producing an insulation material, including the steps of mixing cellulose fibre insulation material with a binder, and applying heat to the mixture created by said mixing.

The invention also provides a pellet, pebble or "the like of insulation material, said pellet, pebble or the like being formed from a mixture of cellulose fibre insulation material and a binder, which mixture i is heated to produce said pellet, pebble or the like. t An embodiment of the invention, which may be preferred, will be described in detail hereinafter.

Loose fill cellulose fibre insulation material (as hereinbefore defined) is mixed with a PVA adhesive, preferably Croda Polystick 23/671 (equivalent to the former The constituents may be generally present in accordance with the embodiment of AU-B-31173/89.

In any event the loose fill cellulose fibre jcspb, 027/flexi 92 4 24 11:1 5 insulation material is preferably mixed with the PVA adhesive, and more preferably with hot and cold water (just cold may suffice) to produce a paste.

The paste is then preferably fed through an extruder, w;hich extrudes a thin core of paste, which is cut off in predetermined size portions or elements.

The extruder may preferably produce a circular crosssection and the extruded core may be cut so that a spherical form of paste element is obtained.

Paste elements could, of course, be produced by other means and/or in other shapes.

After the production of paste elements, the paste elements are subjected to heat and agitation to produce pebbles, pellets o r Sjivvlc- O/jcReSe.

Prototype paste elements were placed in a domestic front-opening tumble drier, in which a stream of hot air blew over elements which were tumbled by the drum of the drier. A preferred temperature for i the hot air is 110°C. The tumble drier, because it was designed to dry clothes, was not totally satisfactory for producing spherical pebbles. However, rounded pellets were produced, and when subjected to a squeeze test, proved to be substantially incompressible.

In practice, it is considered that substantially spherical pellets of something less than icm in diameter, would be produced, and would be optimum.

"Ss Such pebbles or pellets may be used to fill wall S cavities or the like, would not compress under their S jcspe.027/flexi 92 4 24 "6 own weight and would retain their insulating properties.

It is envisaged that building panels could be produced, in which pebbles or pellets of this invention could be sealed or encapsulated, providing for fire-rated equivalents of present polystyrene foam-filled panels.

It can be seen that this invention provides a remarkable new insulation material, which may also be used for loose packaging.

The entire contents of the provisional i specification lodged with Australian Patent Application of which this is the complete I 9* specification is hereby imported into this specification and forms part of the disclosure of this specification.

SJ The claims form part of the disclosure of this specification.

jcspe.027/flexi 92 24