BE1022980B1 - FORMULATION FOR CASTABLE RESIN BASED ON NATURAL FILLERS. - Google Patents

Abstract

This invention relates to a casting resin formulation containing a casting resin and one or more fillers, wherein the filler is selected from the group of renewable fillers. Examples of suitable renewable fillers are materials of vegetable, animal or microbial origin or a mixture of two or more of these. The casting resin is preferably also a curable resin of natural origin.

Description

Formulation for a castable resin based on natural fillers.

This invention relates to a casting resin formulation containing a casting resin and one or more fillers, the filler being selected from the group of renewable fillers. The casting resin hardens to a solid material.

In the context of this invention, the visual properties of the cured resin such as the color and the pattern are mainly determined by the fillers, additionally added pigments or dyes hardly play a role in the appearance. In addition to a unique aesthetic effect, some formulations have surprisingly good shock and impact-absorbing properties. These are attributed to the presence of natural fillers in combination with certain resins.

The casting resins described in this invention can be used in numerous applications, for example for casting floors, for tops, for example of tables or countertops, for design objects and can also be processed into sheets that are laminated on various types of substrates and substrates.

State of the art.

Poured floors are traditionally made from synthetic or mineral raw materials. For example, there is the use of epoxy and polyurethane resins, with or without the addition of mineral fillers, but also cement and concrete formulations. Stone carpets, a combination of stones with a synthetic resin, also fall under the category of cast floors. The unique seamless finish is typical of cast floors. The properties can vary greatly depending on the type. For example, epoxy-based screed floors have a very good resistance to all kinds of chemicals, feel hard and have a high impact resistance. On the other hand, they are scratch-sensitive, not suitable for underfloor heating and are susceptible to cracks. Epoxy floors are mainly used in an industrial environment. Polyurethane floors have a higher elasticity, they feel warmer and are suitable for floor heating. Because of their properties, they are used more often in interior applications: private homes, offices, shops, etc. Stone carpets and cement floors have a unique view, often labeled as "industrial". Because of their higher sensitivity to moisture and dirt, they are often covered with an additional finishing layer, based on epoxy or polyurethane resin.

Poured floors containing raw materials of natural origin are still rare. Examples of raw materials of natural origin include polyurethane resins partly derived from vegetable oils. Depending on the technology and product types, these "natural" polyurethanes can contain up to 70% renewable carbon. Epoxy resins that are partly derived from renewable raw materials are also known. The epoxidized oils and epichlorohydrin are known to be of natural origin. Here too, the renewable carbon content, depending on the technology and product, is usually limited to 70%.

Linoleum is a natural alternative to floor systems or surface finishes. This product consists of linseed oil, natural resins (collophane), natural fillers such as wood flour or cork powder, whether or not natural pigments and minerals. Mixing these components produces a paste or dough that is spread over a fiber mat - typically burlap - in a calender. A linoleum sheet is obtained after the paste has dried. The paste is often covered with a finishing layer to reduce the moisture sensitivity. Linoleum contains a high level of renewable carbon (up to> 95%), it is usually offered in the form of a sheet, but not as a casting resin. Linoleum must therefore be fully glued to the surface to be covered.

Other combinations of renewable fillers with thermoplastic or thermosetting resins are also known. For example, wood flour, nut shells, cork powder or other lignocellulose secondary streams are often formulated with thermoplastic resins to obtain a so-called Wood Plastic Composite (WPC). These mixtures or compounds are produced at higher temperatures (> 140 ° C) and can subsequently be processed into articles, by extrusion or injection techniques. These techniques require the compounds to be melted at elevated temperatures. Repeated exposure of renewable fillers to elevated temperatures results in a browning of the renewable fillers. In the case of WPC, this need not be a disadvantage since these materials are positioned as an alternative to wood.

Incorporation of wood flour in WPC also influences the physical properties of the material, such as reduced shrinkage and a higher impact resistance. Also known are combinations of renewable fibers or granules with a thermosetting resin, such as in fiber plates, MDF, OSB, cork plates, flaxen plates ... In these products, the thermosetting resin is used as a binder to convert a large amount of renewable material into a plate. glue. Since the amount of binder is relatively small compared to the amount of renewable material, this does not fall under "renewable fillers".

Description of the invention

Mold-ready formulations according to this invention contain a casting resin and one or more fillers, at least a part of the fillers being selected from the group of renewable fillers. The casting resin of this invention is obtained by mixing a renewable filler with a resin, which may or may not be of renewable origin.

The formulation of this invention may further contain one or more additives to achieve the intended flow, to promote degassing and / or to achieve an optimum dispersion of the fillers in the resin.

Renewable fillers can be of vegetable, microbial or animal origin. Non-limiting examples of vegetable fillers are lignocellulotic by-products from the oil pressing (press cakes), wood flour, bark, straw from various grains, flax loaves, leaves, seeds ... Non-limiting examples of microbial fillers are microalgae, active sludge, microbial waste from fermentation processes. .. Non-limiting examples of animal fillers are bone meal, fish scales, fish bones, shellfish and insect exo skeletons. Typical of the various fillers is that they are not soluble in water or oil and that they are available in granular form. The diameter of the granules can vary from 10-1000 µm, preferably from 100-800 µm and more preferably from 200-600 µm.

Resins can be of petrochemical or natural origin. Curing can take place by chemical reaction or physical interaction between the various components present in the resin. Most suitable are resins that cure chemically irreversibly by reaction between different components, whether or not under the influence of pressure and limited heat. Non-limiting examples of such resins are polyurethane resins and epoxy resins, whether or not of natural origin. Natural polymers such as carbohydrates (starch, hydrocolloids, chitin ...) and proteins can also be used as a resin. What is important for this invention is that the resins can cure at temperatures of 15 ° C-140 ° C, in order to prevent a discoloration of the natural fillers, preferably of 15 ° C-100 ° C.

The fillers are specifically added to the resins for the purpose of giving a color and pattern to the cured resin. To achieve this, fillers with a pronounced color are preferably chosen, due attention is paid to the grain size distribution and the heat input must be limited. Casting resins based on formulations with fillers that themselves provide the desired coloring, once cured show a coloring over the entire thickness of the material, with a surprising color pattern and depth that cannot be obtained by using (synthetic) pigments or dyes .

Due to the relatively low specific gravity of the natural fillers, it is possible to apply a light-weight casting layer. This makes it possible to use a minimum amount of raw materials to obtain a casting floor of suitable thickness.

The relatively low specific gravity and grain size distribution further offer the advantage that the natural fillers used in this invention slowly sediment into the resin and flow uniformly with the resin. This makes it possible to achieve an even distribution of the fillers over the cast surface, in contrast to many mineral fillers.

The use of natural fillers offers the advantage that they are already pigmented by nature, and in particular that they are resistant to discoloration and that the color is stable to ultraviolet light. This property makes the application of an additional UV-stabilizing finishing layer unnecessary. Without wishing to be bound by this, the inventors have formulated the hypothesis that this UV stability is due to the natural presence of polyphenols and terpenoids in the renewable fillers.

By using granular natural fillers, the inventors have established that the casting resins exhibit minimal shrinkage. This is an important advantage for casting applications and allows to fill milled shapes with a casting resin, and then finish the surface to a seamless end result.

Due to the presence of the granular renewable fillers in the resin, it is possible to effect an improved dissipation of the impact energy, whereby the resin composition of this invention has a shock-absorbing effect. Without being bound by theory, the inventors assume that the homogeneous dispersion of the granular fillers in the resin allows for easier dissipation of the impact or vibration energy through the material, thereby obtaining a shock and vibration damping effect.

The casting resin formulation of this invention is particularly suitable for seamless filling of large surfaces, but also for the production of cured resin sheets. If desired, the sheets may be applied to and / or bonded to a support.

The casting resin formulation of this invention is suitable for manufacturing, inter alia, floor surfaces, wall surfaces, areas of use, for example of a table, countertop, cupboard and the like.

The examples below illustrate the invention.

Examples.

Example 1. Casting resin for milled surfaces.

Cork powder with grain size <500 µm was mixed in Component A of a 2-component natural resin with 70% renewable carbon. Component A mainly consists of an epoxidized linseed oil. Additives to accelerate the curing time and to improve the surface properties (venting additives) were blended into a homogeneous mixture.

After adding the crutch powder, the mixture was poured into a milled plank 40 x 40 cm and 2 mm deep. The casting mixture was found to be self-leveling. After leveling had taken place, the casting mixture was cured in a 90 ° C oven for a maximum of 30 minutes. Once cured, the resin surface was sanded to obtain an even, matte effect.

The result was a seamlessly filled volume with a natural pattern.

Example 2. Casting resin for floors.

The formulation of Example 1 was used for a screed floor system. The resin was cured at room temperature. After 4 days the surface is suitable for finishing.

Example 3. Casting resin for sheets.

The formulation of Example 1 was used to cast sheets. Cork filler, raspberry seeds, peat spits and coffee grit were used as filler. The grain size of the fillers varied from 150500 µm.

The formulation was poured into a mold, the walls of which are covered with a silicone layer, to prevent sticking of the cured mixture to the substrate and to allow the cured material to be released as a sheet.

The color of the sheets obtained varied depending on the fillers used. The sheets were flexible. These sheets are suitable for laminating on a surface.

The sheets are, for example, suitable for lamination on a wool felt. After such lamination, a material was obtained that is flexible and resilient.

Another sheet was laminated on a metal plate, giving the metal plate strong vibration-damping properties.

Claims (11)

Conclusions A casting resin formulation containing a casting resin and one or more fillers, the filler being selected from the group of renewable fillers. A cast resin formulation according to claim 1, wherein the renewable fillers are materials of vegetable, animal or microbial origin or a mixture of two or more thereof. A cast resin formulation according to claim 1 or 2, wherein the vegetable filler is selected from the group of lignocellulose secondary streams from the pressing of oil, wood flour, bark, straw from various grains, flax emblems, leaves, seeds, or a mixture of two or more of these A cast resin formulation according to any of claims 1 to 3, wherein the microbial filler is selected from the group of microalgae, active sludge, microbial waste from fermentation processes, or a mixture of two or more of these. A cast resin formulation according to any of claims 1 to 4, wherein the animal filler is selected from the group consisting of bone meal, fish scales, fish bones, shellfish and insect exo skeletons and mixtures of two or more of these ... 10-1000 µm, preferably between 100 and-800 µm, more preferably from 200-600 µm. A cast resin formulation according to any one of the preceding claims, wherein the resin is a synthetic or natural resin, or a mixture of two or more of such resins. A casting resin formulation according to claim 6, wherein the casting resin is a polyurethane resin or an epoxy resin. A casting resin formulation according to claim 6, wherein the casting resin is a carbohydrate, in particular starch, a hydrocolloid or chitin, or a protein. A casting resin according to any one of the preceding claims which is curable at a temperature between 15 ° C and 140 ° C, preferably between 15 ° C and 100 ° C. Use of the casting resin formulation according to any one of the preceding claims for the manufacture of a cover for a surface or a sheet-like product. The use according to claim 10 for manufacturing a floor surface.