METHOD TO PRODUCE MINERAL WOOD BOARDS

Abstract

This invention relates to a method for manufacturing a mineral wool board, comprising the following steps in the given order: providing mineral wool fibers having a fiber length of 50 to 800 m; gluing the fibers with a liquid binder comprising phenolic resin, whereby the ratio of binder (based on the solids content of the resin of the binder) to mineral wool fibers is 5 to 30% by weight, and pressing the glued fibers using heat and pressure.

Claims

1. A method for manufacturing a mineral wool board comprising the following steps in the given order: a) providing mineral wool fibers with a fiber length of 50 to 800 m; b) gluing the fibers with a liquid binder comprising phenolic resin, whereby the ratio of binder (based on the solids content of the resin of the binder) to mineral wool fibers is 5 to 30% by weight, and c) pressing the glued fibers using heat and pressure to a density of more than 500 kg/m.sup.3.

2. The method according to claim 1, wherein the mineral wool fibers are glass wool fibers and/or rock wool fibers.

3. The method according to claim 1, wherein additives are included to the binder.

4. The process according to claim 3, wherein the additives are mineral fillers, and in particular kaolin, quartz flour, limestone and/or alumina.

5. The method according to claim 4, wherein the mineral fillers have an average grain size d.sub.50 from 10 nm to 250 m, more preferably from 300 nm to 100 m and most preferably from 500 to 900 nm.

6. The method according to claim 4, wherein the mineral fillers are added in an amount of 5 to 150% by weight based on the mass of the solids content of the resin in the liquid binder, preferably 10 to 100% by weight and most preferably 35-90% by weight.

7. The method according to claim 1, wherein the mineral wool fibers have a fiber length of 60 to 700 m, preferably 80 to 600 m and most preferably 100 to 500 m.

8. The method according to claim 1, wherein the step of pressing the glued fibers takes place at temperatures between 130-180 C., preferably 140-160 C. and preferably a specific pressing pressure of 15 to 35 bar.

9. The method according to claim 1, wherein the ratio of binder, based on the solids content of the resin in the binder, to mineral wool fibers is 10 to 30% by weight, preferably 12-30% by weight and most preferably 14 to 25% by weight.

10. The method according to claim 1, wherein the gluing of the mineral wool fibers with binder is carried out in a blow line.

11. The method according to claim 1, wherein the mineral wool fibers are glued with binder by means of mechanical gluing.

12. The method according to claim 1, wherein the pressing is carried out in a continuous double-belt press.

13. The method according to claim 1, wherein the binder is liquid phenolic resin.

14. The method according to claim 1, wherein after pressing, the mineral wool board thus obtained is further processed into a floor panel.

15. The method according to claim 1, wherein the glued fibers are pressed using heat and pressure in such a way that the resulting board has a density of more than 700 kg/m.sup.3, preferably more than 900 kg/m.sup.3 and most preferably more than 1,000 kg/m.sup.3.

16. A mineral wool board comprising: mineral wool fibers with a fiber length of 50 to 800 m; binder in the form of cured resin, in particular cured phenolic resin; mineral fillers with an average grain size d.sub.50 of 10 nm to 250 m, wherein the mineral wool board has a density of more than 500 kg/m.sup.3.

17. The mineral wool board according to claim 16, wherein the mineral fillers comprise caoline, quartz flour, limestone and/or aluminium oxide.

18. The mineral wool board according to claim 16, wherein the mineral fillers have an average grain size d.sub.50 of 10 nm to 250 m, more preferably of 300 nm to 100 m and most preferably of 500 to 900 nm.

19. The mineral wool board according to claim 16, wherein the mineral wool fibers have a fiber length of 60 to 700 m, preferably 80 to 600 m and most preferably 100 to 500 m.

20. The mineral wool board according to claim 16, wherein the ratio of binder, based on the solids content of the resin of the binder, to mineral wool fibers is 10 to 30% by weight, preferably 12 to 30% by weight and most preferably 14 to 25% by weight.

21. The mineral wool board according to claim 16, wherein the mineral wool board has a density of more than 700 kg/m.sup.3, preferably more than 900 kg/m.sup.3 and most preferably more than 1,000 kg/m.sup.3.

Description

DESCRIPTION OF PREFERRED EMBODIMENTS

[0030] In the following, the present invention is explained in more detail with reference to the attached figures, whereby:

[0031] FIG. 1 is a schematic block diagram of a sequence of an inventive process; and

[0032] FIG. 2 schematically shows a plant for carrying out the process or for producing a mineral wool board.

[0033] FIG. 1 shows a schematic flow chart of an example of the inventive method for producing a mineral wool board. In step S1, mineral wool fibers with a fiber length of 50 to 800 m are provided. This can be done, for example, by shredding commercially available rock wool to the desired fiber length. In step S2, a binder is provided which comprises a mixture of liquid resin and mineral fillers. The fillers should have an average grain size d.sub.50 of 10 nm to 250 m. Steps S1 and S2 do not necessarily have to be carried out in the specified sequence, but can also be carried out simultaneously or in a different sequence. The addition of fillers is optional but preferred. In step S3, the binder, which essentially consists of the liquid resin and the mineral fillers, is subjected to an ultrasonic application, whereby the fillers are distributed in the liquid resin and preferably agglomerates of the fillers are destroyed or reduced in size. Step 3 is optional, however preferred, if fillers are used, since the application of ultrasonic energy results in a very gut dispersion of the fillers. In step S4, the mineral wool fibers provided are glued with the binder. The fibers must necessarily be glued after steps S1, S2 and S3, as ultrasonic application only makes sense as long as the mineral wool fibers have not been added to the binder. In addition, step S4 should take place immediately after step S3, as the fillers dispersed by the ultrasonic application can otherwise settle again in the liquid resin. As the last of the steps in step S5, the glued fibers are pressed using heat and pressure to form a mineral wool board.

[0034] FIG. 2 shows schematically a plant for the production of an inventive mineral wool board or for the execution of the inventive method. Reference number 10 refers to a mixer in which liquid resin and fillers are introduced and mixed via a supply 14 for liquid resin and a supply 16 for mineral fillers. Processing takes place in batches. After feeding and mixing the desired quantities of resin and fillers, ultrasound is applied to the binder by means of an ultrasound probe 12. This results in a good distribution or dispersion of the fillers in the liquid resin and a reduction or destruction of agglomerates of fillers. Ultrasound can be applied for a few minutes, such as 5 to 15 minutes. The intensity or strength of the ultrasonic application depends on the materials used, such as the viscosity of the liquid resin and the size and consistency of the mineral fillers. The intensity of ultrasonic application should be selected so that the fillers are well distributed in the liquid resin and larger agglomerates of fillers are effectively crushed or destroyed.

[0035] Reference number 20 refers to a shredder which can be fed with mineral wool or mineral wool fibers via a supply 22. In the shredder 20 the mineral wool fibers are shredded to a fiber length of 50 to 800 m. The correspondingly shortened fibers are fed via a feed 24 to a gluing device 30. The binder, consisting of the liquid resin and the mineral fillers, is fed from mixer 10 to gluing unit 30 via a supply 18. The fibers should be glued immediately after application of the ultrasound. In gluing unit 30 the fibers are glued with the binder. The fibers glued in this way are dried, if necessary, after the gluing device 30 and then fed to a double belt press 40. The dried and glued mineral wool fibers are spread onto a conveyor belt and form a glued fiber mat 42. the fiber mat 42 is fed through the double belt press 40 and pressed into a mineral wool board 44 under the effect of heat and pressure. In this case, the mineral wool board 44 is available as a long strand, which can then be cut to size and further processed if desired.

REFERENCE CHARACTER LIST

[0036] 10 Mixer

[0037] 12 Ultrasonic probe

[0038] 14 Supply of liquid resin

[0039] 16 Feed for fillers

[0040] 18 Binder feed

[0041] 20 Shredder

[0042] 22 Mineral wool supply

[0043] 24 Supply of fibers

[0044] 30 Glue application device

[0045] 40 Double belt press

[0046] 42 Glued fiber mat

[0047] 44 Mineral wool board