DE19526541A1 - Recyclable fibre-reinforced composite material for building applications - Google Patents

Abstract

Mineral, fibre-reinforced composite material which contains 10-60 (14-45)% casein, 20-70 (40-64)% limestone powder and cellulose fibres, esp. 5-50 (15-24)% paper.

Description

The invention relates to mineral, fiber-reinforced Ver composite materials and processes for their production. The like composite materials are used for example in the interior construction as insulation and wall cladding panels but also outside half closed rooms and can be used in plat tenform also as shaped stones or filler or putty are used.

DE-A1-35 45 001 describes a composite material the ground newsprint, vegetable or animal Natural fibers, water-soluble natural glue and a fire retardant mende, putrefactive, preferably borax and boric acid containing component. Furthermore describes the DE-U1-92 00 610 a cellulose-containing, through a hardens  bondable composite material, in which Also use lactic acid casein as a hardenable binder can find.

DE 36 11 080 C1 describes a composite material with a Contains up to 65% by weight of marl and limestone on shredded paper, especially waste paper, the to increase the strength, especially the wet strength, Cement is added. To increase the breakage and bending lines This composite material can still be sawn or Wood chips are added. Due to the content of Ze ment, on formaldehyde contained in sawdust and shavings and on needed for the production of chipboard, in Solidifiers containing sawdust and shavings are those in disclosed in this document, with cement or saw and Wood chips only stabilized composite materials to a limited extent recyclable.

It is an object of the invention to provide a composite material which improved properties and yet recyclable, and a method for producing such a composite to provide material.

According to the invention, a solution is a composite material Containing casein, limestone flour and cellulose fa and manufacturing processes according to the characteristics of Claims 18, 20 and 22 provided.

Calcium-containing materials with a small grain with a carbo nat content between 85% and 100% and a magnesium carbonate are below 5% than in the composite according to the invention limestone powder contained in the material. It understands that calcium carbonate instead of limestone flour containing materials, such as. B. limestone marl, dolomite, Marl, advantageous as components of the invention Composite can be used.  

The material containing cellulose fibers can, for example Hemp, flax, straw (preferably chopped), sisal, coffee fairy or cocoa bean shells, rice bowls, cardboard or pa pier, especially waste paper, as well as all other be knew starting materials for the provision of cellulose fa sern, especially - as recycled material - invented the inventive composite material itself, and any combination tions or components of the aforementioned starting materials include. These materials containing cellulose fibers, in particular the waste paper, can be added to the Composite material removable by the prior art Procedures to be cleaned.

In particular coffee or cocoa bean shells or rice bowls len occur in large quantities. Coffee beans fall here bowl, silver skins surrounding the coffee beans, and Cocoa bean husks as waste when roasting. Rice bowls are obtained as rice feed flour when peeling rice.

Casein is a phosphorus protein, which e.g. B. in the form of Caseinogen colloidally dissolved as calcium salt in mammalian milk is. By adding acid or rennet, or by one Lactic acid fermentation process precipitates casein. By on acid casein with calcium carbonate can casein glue are produced as wood glue, label glue and serve for paper gluing. Putties for fiberboard and Floor coverings made from casein glues with the addition of Fillers such as sand or cement, but not composite substances of the type according to the invention are known per se.

The composite material according to the invention has a high Bending tensile strength as well as high elasticity, even with a thickness of 3 to 4 mm. The composite material can be Process well, especially screw well and break when Do not unscrew.  

The low weight and high bending tensile strength give hen the composite material according to the invention good transport properties. By increasing the proportion of cellulose fibers, or paper, the specific Reduce the weight of the composite material according to the invention.

By adding cement, the durability of the Composite material against water, weather influences, rot nis, fungal and insect attack and heat resistance increase in an advantageous manner. It has been shown that the properties of the composite material already Add 6% by weight of the added dry matter in desired improvement and the composite material this makes it particularly water-resistant. The relative small amount of cement to achieve this before is added, increases the specific weight of the Composite material advantageously only slightly.

Against moisture absorption can the invention Composite material borates, and / or bromine but also extinguished or coated lime. The addition of Borates - the salts of boric acids - and / or bromine is used further disinfection, which among other things Mold infestation can be avoided - the disinfectant effect of the borates, or the bromine itself is known -, and also advantageously increases the heat resistance of the composite material according to the invention.

The addition of non-slaked lime is also water-repellent and germicidal. Likewise, the composite material, preferred wise untreated, sheep's wool can be added. The lano Lin or wool grease from sheep's wool is particularly effective in water repellent. The sheep's wool can advantageously Gerü Dismantle the surface and have a bacteria-inhibiting effect.  

For the production of the composite material according to the invention the cellulose fiber containing material and the other ingredients, especially limestone powder and the casein, mixed and then added water, preferably kneaded in small units. It ver it is clear that instead of kneading, all other suitable ones Mixing processes can be used advantageously. It can be advantageous to add the cellulose fibers before to crush the slurry. It can also be beneficial be the cellulose fibers before adding them to this one to clean slurry.

Advantageously, it contains water before starting give the other dry mix Materials in the desired concentration, which the Ver should have bundled material after its manufacture. Ins The dry mix can be special even before the water addition of cement included.

The addition of an unnecessarily large amount of water to the ver bundwerkstoff at the end of the manufacturing process with a lot Effort would have to be removed again by the addition of water in small quantities is prevented. This is particularly advantageous if the dry mix contains unlime lime because doing so is excessive strong reaction of the dry mix or lime with the added water can be avoided. In this case the amounts of water added are dosed so that sets a temperature of approx. 70 ° C. After completion of the Reaction is quenched with water and the slurry mixed up. The slurry thickens when it cools.

According to a second, advantageous manufacturing process material containing cellulose fibers Limestone powder slurried by water. The amount of water is adjusted to the amount of material. In order not to use too much water  So much water has to be added that a kneadable mass is formed. This mass is preferred processed only after a certain time to a process of limestone separating the cellulose fibers letting flour take place like he did for a batch Cellulose fibers, glue and inorganic material e.g. B. is known from DE-A1-29 16 101. Only then will added the casein.

It can also be an advantage after a certain time to give up this slurry of cement. It is conceivable that Slurry, at least during the the cellulose fibers separating process by a mixing or stirring device keep moving. Depending on the chosen process flow however, this process separating the cellulose fibers behaves expire relatively quickly, so that the selected time period can be chosen very short.

After the mixing process, the slurry is pressed. By the pressure applied here can be the density of Cellulose fibers, or the water content of the Ver regulate the material. The denser the storage of the Cellulose fibers, or the lower the water level after pressing the higher the strength of the composite material according to the invention.

The pressed material can then luftge overnight be dried. Of course there are also others Dry process conceivable. It was observed that the he post-curing composite material according to the invention tet. However, it is conceivable that not all waterbe constituents of the composite material according to the invention Pressing and drying can be removed.

To avoid mold and infestation with Bacteria benefit from the aqueous slurry  Add vinegar, preferably apple cider vinegar. A composite plant material, in particular a composite material according to the invention, which consists of a water content Slurry is obtained and this aqueous slurry contains vinegar, preferably apple cider vinegar, is particularly resistant to mold and behaves insensitive to bacterial infestation. Due to the content of apple cider vinegar, the invention Slurry has a crumbly consistency, which is beneficial in further processing of the slurry. As well however, it is also conceivable for the composite according to the invention material according to its shape from the outside with vinegar or treat with apple cider vinegar. Furthermore, it can be from above reasons mentioned be advantageous, the invention Composite pre-treated apple pomace admit.

It is understood that the composite material according to the invention all fungicides or pe which can be found in the prior art Sticides can advantageously contain to this to protect against infestation by organisms of any kind. Here, these fungicides or pesticides can be used during each suitable process step, advantageously, in the composite material are introduced or on the Surface to be applied. Furthermore, it goes without saying that the composite to any suitable process step all known substances to increase the heat or water resistance serve - such as cement - Advantageously added or applied to this can.

In the production of the composite material according to the invention fes, in particular according to the methods described above, can ver the production of polluting industrial waste water be avoided. The added water can be after pressing  be recovered and recycled to the slurry mung can be used.

The advantageous recyclability of the Ver bundwerkstoffes makes it possible in particular for To use coffins. In particular, this composite fabric, possibly using veneers or suitable coloring, also for furniture, especially for Kitchen furniture, find use. It is understood that the composite material according to the invention also for all others, known types of use of generic composite materials can be used advantageously.

Various designs are exemplary in Tables I to III Examples of composites according to the invention their percentage of dry matter or their percentage of water or apple cider vinegar in the aqueous Slurry described above Manufacturing processes were produced and the above be have written, advantageous properties.

In the exemplary embodiments 1 to 4, 9, 10 and 12 to 38 dry casein was used as the starting material. The Casein had a grain size of 30/60 in the execution play 9, 10 and 33 to 38, while the grain in the Embodiments 12 to 32 90/110 was.

In the exemplary embodiments 5 to 8 and 11, fresh, that is, water-containing casein and a necessary amount of rest ge of water used as a starting material.

In the embodiments 3, 4, 34 and 37 was considered off a limestone flour with a grain size of 0.1 used. In the exemplary embodiments 6, 8 to 33, 35, 36 and 38 had the limestone used as the raw material flour a grain size of 0 to 0.09, while the rest  Embodiments different types commercially available of limestone flour were used without grain size.

The embodiments of apple cider vinegar Apple cider vinegar used was in a concentration of approx. 5% in front.

To produce the be in the embodiments 1 to 4 The first composite material to be written was limestone flour and paper slurried in water before the casein was added.

In the described in the other embodiments Composites were the first to be manufactured Weighed dry components of the composite and mixed. With the addition of small amounts, the dry Mix the liquid with kneading. The amount of liquid was metered in such a way that the up slurry had a dough-like consistency. Subsequently the composite material was created in this way dene slurry pressed into the desired shape as well dried.

For example, the composite material according to the invention in Form of plates are formed. For this, the on slurry z. B. on a sheet with 1 to 2 mm in size, about 0.5 to 1.5 cm spaced drain holes which is laterally limited by a frame. Then apply the slurry applied with a second similar sheet covered. Between the sheets and the slurry can each have a layer of filter paper or the like may be arranged to separate the Composite material after pressing or after drying to facilitate. Using screw clamps, the two Sheets joined together for a period of approx. 12 hours presses. Then the composite material at about 30 ° C.  dried for about 24 hours. Against faults can the composite material during the drying process, e.g. B. with Weights are loaded.

It goes without saying that for the production, in particular for industrial manufacturing, other manufacturing processes can be used advantageously.

It shows that the cement or lime samples - Embodiments 9 to 11, 13, 20 to 23 and 37 and 38 - are waterproof and resistant to mold. There against the Ver described in embodiment 28 too low a proportion of cement, which at this embodiment must be approximately doubled to a waterproof and mold-resistant composite to obtain material. Also the composite with borax materials of the embodiments 18, 19, 26, 27, 29 to 31 and 36 prove to be relatively mold-resistant dig. The version made with the addition of apple cider vinegar Example 12 to 14, 24, 25, 34 and 35 also show increased resistance to mold.  

Table I

Table III

Claims (23)

1. Mineral, fiber-reinforced composite material, characterized by a content of casein, limestone powder and cellulose fiber containing material. 2. Composite material according to claim 1, characterized by a content of 10% to 60%, preferably 14% to 45%, Casein. 3. Composite material according to claim 1 or 2, characterized by a content of 20% to 70%, preferably 40% up to 64%, limestone flour. 4. Composite material according to one of claims 1 to 3, ge characterized by a content of paper. 5. Composite material according to claim 4, characterized by a content of 5% to 50%, preferably 15% to 24% Paper. 6. Composite material according to one of claims 1 to 5, characterized by a coffee bean content len. 7. The composite material according to claim 6, characterized by a content of 5% to 30%, preferably 7% to 25%, Coffee bean shells. 8. Composite material according to one of claims 1 to 7, characterized by a content of rice husks.   9. The composite material according to claim 8, characterized by a content of 10% to 60%, preferably 18% to 43%, Rice bowls. 10. Composite material according to one of claims 1 to 9, characterized by a content of, preferably ge chopped straw, preferably about 13%. 11. Composite material according to one of claims 1 to 10, characterized by a content of fungicides and / or pesticides. 12. Composite material according to one of claims 1 to 11 characterized by a content of cement. 13. The composite material according to claim 12, characterized by a content of 3% to 25%, preferably 6% to 20%, Cement. 14. Composite material according to one of claims 1 to 13, characterized by a content of borax. 15. Composite material according to claim 14, characterized by a content of 2% to 30%, preferably 3% to 15%, Borax. 16. Composite material according to one of claims 1 to 15, characterized by a content of slaked lime, of preferably about 19%. 17. Composite material according to one of claims 1 to 16, characterized by a content of, preferably untreated, sheep's wool.   18. Composite material according to claim 17, characterized by a content of 2% to 10%, preferably 4% to 5%, preferably untreated sheep's wool. 19. Process for producing a mineral, fiber reinforced composite, especially after a of claims 1 to 18, characterized, that at least casein, limestone flour and zel Material containing lulose fibers in the desired condition composition mixed dry, the dry mix then water, preferably in small amounts units, added with kneading and this way resulting slurry pressed and dried becomes. 20. Manufacturing method according to claim 19, characterized records that the dry mix contains cement. 21. Process for producing a mineral, fiber reinforced composite, especially after a of claims 1 to 20, characterized, that initially cellulosic material at least slurried with water from limestone powder, after a pro separates the cellulose fibers added casein for a selected time and the slurry formed in this way is pressed as well is dried. 22. Manufacturing method according to claim 21, characterized records that the cellulose fibers and limestone flour containing slurry, after expiry of a cell process for a chosen Time cement is abandoned.   23. Process for producing a mineral, fiber reinforced composite, especially after a of claims 1 to 22, wherein the composite fabric from a water content Slurry is obtained characterized, that the aqueous slurry contains a vinegar content, preferably apple cider vinegar.