Classifications

• • C—CHEMISTRY; METALLURGY
  • C03—GLASS; MINERAL OR SLAG WOOL
  • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
  • C03C25/00—Surface treatment of fibres or filaments made from glass, minerals or slags
  • C03C25/10—Coating
  • C03C25/24—Coatings containing organic materials
  • C03C25/40—Organo-silicon compounds

Definitions

• the present invention relates to a rigid mineral fibre element, such as a facing element for buildings, comprising a mineral fibre layer and a surface layer in the form of a paint layer, wherein the mineral fibre layer comprises mineral fibres added in the form of wads and/or single fibres and a thermocurable or thermoplastic binder added in the form of a powder.
• DK patent application No. 6049/89 discloses a composite material for use as a starting material in the manufacture of moulded elements, which composite material consists of flocks obtained by disintegration of a filt consisting of mineral insulation fibres and a thermocurable and hot meltable binder, e.g. phenol resin, epoxy resin, polypropylene or silicone.
• a thermocurable and hot meltable binder e.g. phenol resin, epoxy resin, polypropylene or silicone.
• NO patent application No. 901,555 discloses a composite material which is useful as starting material in the manufacture of moulded parts, which composite material consists of mineral fibres and from 1 to 70% by weight of novolak resin and from 0.5 to 70% by weight of silicone resin based on the finished composite material.
• a prior art mineral fibre element for use as a facing sheet for buildings comprises a mineral fibre layer and a surface layer in the form of a layer of a water-based paint, wherein the mineral fibre layer consists of mineral fibres added in the form of wads and/or single fibres and a thermocurable phenol resin added in the form of a powder.
• a water-based paint as such a paint is far more environment-friendly than other types of paint both in the manufacture of the element and in the use thereof.
• a water- based paint involves the drawback that the water suction capacity of the finished element is considerably increased due to content of surface-active agent in the paint.
• various oils, including silicone oil to the mineral fibre layer of the known element in order to increase its water repellency.
• these attempts have resulted in an unacceptable reduction in the strength and life of the element and at the same time a subsequent application of a paint on the surface of the element was made impossible.
• the object of the present invention is to increase the water repellency of a plate of the type stated in the introductory part of claim 1 without reducing the strength and durability of the element to an unacceptable degree and without preventing a subsequent application of a paint.
• the mineral fibre layer comprises from about 0.01% by weight to about 0-5% by weight of silicone resin added in the form of a powder.
• the element has a water repellency which is significantly higher than that of a corresponding element without silicone resin, which is assumed to be due to the fact that the silicone resin eliminates or reduces the capillary effect in the porous mineral fibre layer.
• the element according to the invention has a strength which is substantially equal to and in some cases even greater than that of a corresponding element without silicone resin.
• silicone resin added in the form of a powder as compared to e.g. oils and silicone resin added in the form of a liquid will only form a coating on a relatively small portion of the fibre surface and hence to a far less degree prevent a binding between binder and fibres to adhere the fibres together.
• hen silicone resin is added in the form of a powder, only the fibres or the fibre portions located in close proximity to the silicone resin particles will be coated with silicone resin when the said particles are melted.
• use of water repellent silicone resin in the above mentioned amount does not prevent the application of a paint layer, including a water-based paint, on the surface of the mineral fibre layer. 5
• the element according to the invention presents the advantage that the paint layer can be formed with a smaller amount 15 of paint per area unit compared to an element without silicone resin and at the same time the paint layer obtained is more even and uniform.
• the mineral fibre layer according to the invention may have the form of a plate or any other desired form, such as curved items. 25
• starting material e.g. mineral fibre matts or mineral fibre waste 30 material, e.g. in the form of edge cuts, can be used.
• the starting material is subjected to disintegration into small wads and/or single fibres, which disintegration can be effected with any suitable known apparatus or combination thereof,
• ' ⁇ + 35 such as spike rollers, carding machines, hammer mills, centrifugal blowers, etc.
• Powdered binder and powdered silicone resin are then added to the disintegrated mineral fibre material and a mixing of the said co ponents is effected, which mixing can be carried out e.g. in a chamber equipped with a stirrer.
• the mixture obtained is subsequently conveyed to a distribution chamber, from which it is laid out on a support in an even layer of an uniform thickness.
• the laid out mineral fibre layer is then compressed in a heating press at a press plate temperature of e.g. between 150 ⁇ C and 300 ⁇ C and at a pressure of e.g. between 20 bars and 30 bars for activation of the binder and the silicone resin, and subsequently the compressed layer- s cooled to form a rigid plate.
• a press plate temperature e.g. between 150 ⁇ C and 300 ⁇ C and at a pressure of e.g. between 20 bars and 30 bars for activation of the binder and the silicone resin
• one or more paint layers are applied to the surface of the plate, e.g. a primer and a top layer.
• the application may be effec ⁇ ted with sprayer, pressure roller or curtain painting device or by combinations thereof.
• drying is effected between the applications, which drying e.g. is effected in a hot-air furnace.
• the mineral fibres used for the manufacture of the element according to the invention may be rock fibres, glass fibres, slag fibres, preferably rock fibres.
• thermocurable binder in the present invention preferably a phenol resin, such as phenol formaldehyde and novolak, or an epoxy resin, most preferably a phenol resin, is used.
• thermoplastic binders examples include polyurethane, polyethylene and polypropylene.
• thermocurable or thermoplastic binder is preferably used in an amount of from 4 to 15% by weight, preferably from 6 to 9% by weight, based on the mineral fibre layer.
• the silicone resin used may be methyl polysiloxane. As mentioned above the silicone resin is used in an amount of from about 0.01 to about 0.50% by weight, preferably from about 0.03 to about 0.20% by weight and most preferably from about 0.05 to about 0.10% by weight, based on the mineral fibre layer.
• the particles in the powdered silicone resin preferably have a size of less than 500 ⁇ m, more preferably less than about 350 ⁇ m and most preferably less than about 250 ⁇ m.
• the mineral fibre layer in the element according to the invention preferably has a density of from about 800 kg/m 3 to about 1200 kg/m 3 , preferably from about 900 kg/m 3 to about 1100 kg/m 3 .
• paint in the surface layer either a water-based paint or a paint based on an organic solvent, such as an oil-based paint, may be used, but a water based paint is preferably used.
• the plates were produced in the following manner:
• the disintegrated fibre material was then filled into a container, to which were added 650 g phenol resin in the form of a powder and 0 g, 10 g and 50 g methyl polysiloxane, respectively, in the form of a powder and comprising particles having a size of from 0.1 to 240 ⁇ m, and the fibre and powder material was mixed by means of a stirrer mounted in the container.
• a fibre distribution apparatus of the type described in US patent No. 4,494,278, i.e. an apparatus comprising a distribution chamber having a plane perforated bottom plate and a number of blade stirrers which can be caused to rotate in a short distance above the bottom plate, which distribution chamber is located a short distance above a portion of an endless forming wire, and which apparatus further comprises a suction box located below the forming wire vis-a-vis the distribution chamber.
• the above mentioned mixture was laid out on the forming wire in an even layer with a uniform thickness of about 100 mm.
• the layer laid out was then compressed in a heating press having a press plate temperature of 250 ⁇ C and at a pressure of 25 bars, thereby causing the thermocurable phenol resin and silicone resin to be activated.
• the compressed mineral fibre layer was subsequently cooled at room temperature to form a rigid plate having a thickness of 10 mm and a density of 1000 kg/m 3 .
• a primer in the form of a water-based acrylic paint and with a solids content of 50% was then appl ed with sprayers onto one side of the plate in an amount of 100 g/m 2 , and the applied paint layer was dried in a hot-air furnace at a temperature of 100°C.
• a top layer in the form of a water-based acrylic paint and with a solids content of 50% was finally applied with sprayers onto the primed side of the plate in an amount of 150 g/m 2 , and the applied top layer was dried in a hot-air furnace at a temperature of 100 ⁇ C.
• the bending strength and the water suction capacity of the finished plates were then determined.
• the bending strength was determined partly for non-aged plates and partly for plates which had been subjected to an artifical ageing.
• the artificial ageing was effected by submerging into a water bath 10 test plates cut out of the same ready made plate and having a size of 4 x 11 cm, and heat treating them therein for a period of 1 hour and at a temperature of 70 ⁇ C. Prior to the heat treatment a small amount of sulpho was added to the water bath in order to reduce the surface tension of the water.
• the bending strength was determined by horizontally mounting a test plate having a size of 4 x 11 cm in the transverse direction of two metal bars having a mutual spacing of 10 cm, and subsequently moving downwards a third bar centered between the two other bars and which was provided with a dynamometer in vertical direction at a rate of 20 mm/min until rupture of the test plate, thereby measuring the bending strength.
• the bending strength of a given ready made plate was determined as an average of 10 test plates cut out of the said plate.
• the water suction capacity of a given ready made plate was determined by weighing 3 test plates cut out of the said plate and having a size of 7 x 21 cm and then placing them upright in separate beakers of 400 ml and with a water level of 2.5 cm. After water saturation the test plates were weighed again and the water saturation degree of the plate was then determined as an average of the water saturation degree of the three test plates.
• both plates according to the invention have a drastically reduced water suction capacity as compared to the plate with no content of silicone resin.
• Both plates according to the invention had a more even and uniform paint layer and hence a higher glaze than the plate without silicone resm.
• the bending strength of the produced plates, both for non-aged and aged plates, and the water suction capacity of the plates were determined by use of the test methods described in example 1 and by use of the ageing process described below.
• the artificial ageing was effected by subjecting 10 test plates cut out of the same ready made plate and having a size of 4 x 11 cm to a total of 400 treatment cycle, said treatment cycle consisting of 1) sprinkling with water for a period of 3 minutes and 2) exposure to UV light at an intensity of 650 Watt/m 2 and at a wavelength spectrum of from 300 to 800 nm for a period of 27 minutes.
• the treatment was carried out in a special furnace of the make "Herraus Instrument GmbH".
• the plates according to the invention had a more even and uniform paint layer and hence a higher glaze than the plate with no silicone resin.

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• Life Sciences & Earth Sciences (AREA)
• Chemical & Material Sciences (AREA)
• General Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Geochemistry & Mineralogy (AREA)
• Materials Engineering (AREA)
• Organic Chemistry (AREA)
• Laminated Bodies (AREA)
• Reinforced Plastic Materials (AREA)
• Surface Treatment Of Glass Fibres Or Filaments (AREA)

Priority Applications (3)

Applications Claiming Priority (2)

Publications (2)

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ID=8101688

Family Applications (1)

Country Status (5)

Cited By (2)

Citations (2)

Family Cites Families (3)

• 1992
  • 1992-09-18 DK DK116192A patent/DK116192D0/da not_active Application Discontinuation
• 1993
  • 1993-09-17 AU AU48150/93A patent/AU4815093A/en not_active Abandoned
  • 1993-09-17 DE DE4392078T patent/DE4392078T1/de active Pending
  • 1993-09-17 DE DE4392078A patent/DE4392078C2/de not_active Expired - Lifetime
  • 1993-09-17 WO PCT/DK1993/000301 patent/WO1993022895A2/en active Application Filing
  • 1993-09-17 GB GB9505061A patent/GB2286409B/en not_active Expired - Lifetime

Patent Citations (2)

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