INSULATING PRODUCT

Abstract

The invention relates to the use of an adhesive in particulate form for securing a facing to a main surface of a mineral wool blanket.

Claims

1. Method of manufacturing a mineral wool insulating product comprising a mineral wool blanket having a facing secured to one of its main surfaces, the method comprising securing an adhesive coated surface of the facing to one of the main surfaces of the mineral wool blanket by application of heat and pressure wherein the adhesive coated surface of the facing comprises an adhesive in particulate form.

2.-15. (canceled)

16. The method of claim 1, wherein the method comprising, sequentially: a) applying the adhesive in particulate form to a major surface of the facing; b) securing the adhesive in particulate form to the major surface of the facing by applying heat to provide the adhesive coated surface of the facing; c) the securing of the adhesive coated surface of the facing to the main surfaces of the mineral wool blanket by application of heat and pressure.

17. The method of claim 16, further comprising packaging the facing to which the adhesive in particulate form has been secured by rolling the facing in the form of a cylinder and subsequently unpackaging the facing prior to securing the adhesive coated surface of the facing to one of the main surfaces of the mineral wool blanket by application of heat and pressure.

18. The method of claim 1, wherein the adhesive in particulate form is selected from: polyethylene, polypropylene, copolyester PES, EVA, epoxy-polyester, a thermosetting adhesive and combination thereof.

19. The method of claim 1, wherein the adhesive in particulate form comprises a thermosetting adhesive; and wherein securing the adhesive coated surface of the facing to one of the main surfaces of the mineral wool blanket by application of heat and pressure comprises curing the thermosetting adhesive.

20. The method of claim 1, wherein securing the adhesive coated surface of the facing to one of the main surfaces of the mineral wool blanket is carried out by passing the mineral wool blanket and the facing through a portion of the curing oven at a temperature of 180 C. for a duration which is 20 seconds.

21. The method of claim 20, wherein passing the mineral wool blanket and the facing through a portion of the curing oven at a temperature of 180 C. is carried out for a duration 5 minutes.

22. The method of claim 1, wherein securing the adhesive coated surface of the facing to one of the main surfaces of the mineral wool blanket comprises pressing the facing between the mineral wool blanket and heated drum.

23. The method of claim 22, wherein the heated drum has a surface temperature of 40 C. and wherein the facing is pressed between the mineral wool blanket and heated drum for a duration which is 2 seconds.

24. The method of claim 23, wherein the facing is pressed between the mineral wool blanket and heated drum for a duration which is 30 seconds.

25. The method of claim 1, wherein securing the adhesive in particulate form to the major surface of the facing comprises heating the adhesive in particulate form to a temperature which is 50 C. and 250 C.

26. The method of claim 1, wherein the adhesive in particulate form has a particle size such that 90% by weight of the particles have a particle size in the range 20 m to 550 m.

27. The method of claim 1, wherein the adhesive in particulate form has a particle size such that 90% by weight of the particles have a particle size in the range 70 m to 350 m.

28. The method of claim 1, wherein the amount of adhesive in particulate form applied to the facing is 5 g/m.sup.2 and 30 g/m.sup.2.

29. The method of claim 1, wherein the facing comprises a facing selected from a woven veil, a woven glass veil, a non-woven veil, a non-woven glass veil, a coated veil, a kraft layer, a metallised layer, an aluminium layer, a PET layer and a fibrous reinforcing scrim.

30. The method of claim 1, wherein the facing comprises a colouring agent which darkens the facing.

31. The method of claim 1, wherein, prior to application of the adhesive in particulate form, the facing has a surface weight in the range 30 g/m.sup.2 to 350 g/m.sup.2.

32. Method of securing a facing having a surface weight in the range 30 g/m.sup.2 to 350 g/m.sup.2 to a main surface of a mineral wool blanket comprising sequentially: a) applying an adhesive in particulate form to a major surface of the facing, the adhesive in particulate from being selected from polyethylene (PE), polypropylene (PP), copolyester PES, EVA, epoxy-polyester, a thermosetting adhesive and combination thereof; the adhesive in particulate form having a particle size such that 90% by weight of the particles have a particle size in the range 20 m to 550 m; and wherein the amount of adhesive in particulate form applied to the facing is 5 g/m.sup.2 and 30 g/m.sup.2; b) securing the adhesive in particulate form to the major surface of the facing by applying heat to provide an adhesive coated surface of the facing; and c) securing the adhesive coated surface of the facing to the main surfaces of the mineral wool blanket by application of heat and pressure.

Description

[0032] An embodiment of the invention will now be described, by way of example only with reference to the accompanying drawing of which:

[0033] FIG. 1 is an image of a facing removed by a peel test from a mineral wool blanket not in accordance with the invention; and

[0034] FIG. 2 is an image of a facing removed by a peel test from a mineral wool blanket in accordance with the invention.

[0035] A glass veil having an area weight of about 60 g/m.sup.2 is positioned on a conveyor. The veil comprises glass fibres with a cured urea extended formaldehyde resin and a black pigment.

[0036] A thermoset adhesive in particulate form for which 90% of the particles by weight have a particle size in the range 20 m to 550 m is deposed over substantially the entire major surface of the glass veil in an amount of about 10 g/m.sup.2. The thermoset adhesive in particulate form (Starpow 100 from Dakota) is then secured to the major surface of the glass veil by passing the uncoated surface of the facing over a heated calender held at a temperature of about 125 C., which partially melts and secures the particulate adhesive to provide a glass veil having an adhesive coated surface.

[0037] The glass veil with the adhesive coated surface is cooled at ambient temperature (about 20 C.) before being packaged by rolling the glass veil in the form of a cylinder. The packaged glass veil is transported to a different location where it is unpackaged and unrolled.

[0038] The glass veil is then applied to the major upper surface of a glass wool blanket running continuously on a conveyor, the blanket comprising freshly formed glass fibres 2 and uncured binder. The glass veil and the glass wool blanket pass through a curing oven, the glass veil being pressed against a major surface of the mineral wool blanket by the flights of the curing oven. The temperature in the curing oven (up to about 250 C.) cures the binder of the mineral wool blanket and secures the facing to the major surface of the mineral wool blanket via the particulate adhesive. The glass wool mineral wool blanket has a density of about 19.5 kg/m.sup.3.

[0039] Once fully cooled having passed through the curing oven, the facing 1 of the glass wool mineral wool blanket is removed by hand in a peel test. The surface of the facing that had been attached to the mineral wool blanket is shown in FIG. 2.

[0040] A second glass wool mineral wool blanket was manufactured in the same way, other than the adhesive used to secure the facing to the mineral wool blanket. In the case of the second mineral wool blanket, the facing was secured to the mineral wool blanket by a PVOH adhesive applied to the facing as a liquid in the form of bands having a width of 5 mm spaced by a distance of 80 mm just before application of the facing to the mineral wool blanket and passage through the curing oven. Once fully cooled having passed through the curing oven, the facing 1 of the glass wool mineral wool blanket is removed by hand in a peel test. The surface of the facing that had been attached to the mineral wool blanket is shown in FIG. 1.

[0041] In FIG. 2 the portion of the surface area of the facing to which the fibres are still secured after the peel test is about 75% of the total surface area, whilst the portion in FIG. 1 is less than 25%.