DE20111670U1 - Binder for loose solids - Google Patents

Description

Binder for loose solids

The invention relates to binding agents for loose solids, in particular for the production of molds, models or objects from mixtures of binding agents and loose solids, especially for crafting, modeling and designing sculptures, reliefs, pictures and other hobby, creative or artistically designed objects.

Binding agents for loose solid particles are known in principle.

For example, according to [1], according to company publications “UNIVEST 43.03.063/08.91: Product information from Hüls on “UNIVEST T ^w” , mixtures of liquid polybutadiene as a binding agent and sand as a loose solid are used for surface fixings in building construction or as level screed and in road construction. These mixtures generally harden at room temperature in around 24 hours. The disadvantage here is that an unpleasant smell develops when the binding agent-solid mixture hardens and also later, and the long time it takes for the polybutadiene to harden. Another disadvantage is that such binding agent-solid mixtures should not come into contact with the skin if possible and cannot be hardened using known acceleration methods, such as microwave energy.

From [2] DE 200 20 012 Ul, decorative material is known which consists of a mixture of water, coloured sand or shell granulate and a binding agent, whereby inorganic substances such as clay or bentonite are proposed as binding agents.

Dyes or pigments used for coloring can also be bound in a fast-curing plastic, preferably on a two-component basis. This material should be malleable by adding water and, for example,

harden within 24 hours. The articles produced with this method can be softened again by adding water after drying and can be made malleable again. The disadvantage here is that no permanently solid bodies are available and that it takes a relatively long time for the molded bodies to harden.

Furthermore, it is also known from [3] DE 40 08 980 C2 to produce and use plastic masses for kneading, modeling, handicrafts and decorating, which, in addition to organic plasticizers and other fillers, are said to contain polyalkyl methacrylate (PAMA), in particular polymethyl methacrylate (PMMA), polyethyl methacrylate (&Rgr;&Egr;&Mgr;&Agr;), polypropyl methacrylate (PPMA) or polybutyl methacrylate (PBMA), as a binder, filler and/or further additive.

Since organic plasticizers are often problematic for the use of materials for children and sensitive people and since they usually cannot be used to create quickly curing products, these materials can only be used in certain areas and are not universally suitable.

The object of the invention is therefore to propose binding agents for loose solids, in particular for materials for crafting, modeling and creating sculptures, reliefs, pictures and other hobby or artistically designed objects, which do not have the disadvantages mentioned and which can be quickly hardened in particular by using microwave energy. It is also the object of the invention that the binding agents according to the invention are easy for the user to process, ie that the binding agents should be easy to mix with the loose solids to be bound. In addition, preferred applications should be shown.

These objects are achieved with the features included in claims 1 and .

Advantageous design and further training of the

The solutions according to the invention are covered by the further claims and presented in the examples.

The particular advantages of the binders according to the invention lie in the possibility of drastically shortening the curing times of the binder itself and of the mixtures of the binder with the loose solids, as well as the products and structures of various kinds produced therefrom, in particular when microwave energy is supplied.

The binders according to the invention for loose, granular solids are universally usable plastic dispersions based on acrylate or urethane, to which other additives can be added or mixed if necessary. The binders according to the invention made from plastic dispersions based on acrylate are preferably dispersions of a copolymer of acrylic acid esters or a polyacrylate or a mixture of the two in different mixing ratios. Water is generally used as a carrier substance for these plastic dispersions. The solids content of plastics in the dispersions is preferably between 20 and 50 percent by weight of the binder. The binder dispersions can also contain small amounts of surfactants, glycols, organic solvents, preservatives and other substances as further additives.

Instead of acrylate dispersions, polyurethanes (PUR) can also be used as binders, in particular so-called PUR prepolymers or MDI prepolymers = diphenylmethane diisocyanate, can be used in dispersed form or in solution.

The binders according to the invention can also be colored as desired with colorants, such as pigments or soluble dyes, whereby differently colored binders or mixtures of binders with solids can be mixed or blended with one another.

Colored binders with small amounts of added solid particles can also form a type of three-dimensional paint, preferably in liquid to viscous form. Images made with these can then also be hardened using microwave energy. It should be noted that the colorant content should preferably not exceed 10% by weight of the binder. The colorant content is particularly favorable at 2% by weight. The pigments can be used pure, as pigment pastes or as - preferably aqueous - pigment preparations. Differently colored binders can also be mixed with one another without any problem. The curing times are not extended, or not significantly extended, by the addition of colorants such as pigment pastes. They can be, for example, 2-3 minutes at 800 W in the microwave or alternatively 2-3 hours in the oven at 60 ^° C or 16-20 hours at room temperature.

Examples of a variety of possible pigments that can be added to the binder include Colanyl violet, Flexonyl blue or Unisperse yellow. As an alternative to the pigments, dyes such as cochineal red can also be added.

Various granular materials, pure or mixed with one another, can be used as loose solids, which may be used to produce plastic products as mixtures with the binding agent, such as sand, natural sand or decorative sand, e.g. of fine to medium grain, hollow microspheres made of glass or plastics and/or kaolin, grit, fine gravel or other granules, powder or chips, e.g. also made of various metals or plastics. Furthermore, organic biomaterials can also be used as loose solids, such as coffee powder, coffee grounds, wood chips or wood dust.

Also fibertnaitJeTiali-ejn «ocfer *cotton ä£tigfe:*3to£fE "Jcönnen

can be easily mixed with the binding agent, shaped and then cured. Fiber mats, textiles or parts of these can also be processed with the binding agent and, after curing, receive a solid or flexible structure.

However, it is also possible that various loose solids, such as natural sand and hollow microspheres, are mixed and processed and cured together with the binder according to the invention in the same batch.

The invention will be explained in more detail using some examples.

Framework example (binder/starting components/BM-X) :

70 -100 wt.% plastic dispersion(s), 0-10 wt.% colorant, 0-30 wt.% water (additional), 0 - 5 wt.% other additives.

Formulation example 1 (binder/BM-I) : 100 wt.% copolymer of acrylic acid ester.

Formulation example 2 (binding agent/BM-2) : 80 wt.% copolymer of acrylic acid ester, 20 wt.% polyacrylate dispersion.

Formulation example 3 (binder/BM-3) : 30 wt.% copolymer of acrylic acid ester, 70 wt.% polyacrylate dispersion.

Formulation example 4 (binder/BM-4) : 30 wt.% copolymer of acrylic acid ester, 58 wt.% polyacrylate dispersion, 05 wt.% pigments,
07% by weight water.

Formulation example 5 (binder/BM-5):

100 wt.% B^?-prep ^: alymQr-Ö5.spserg»ipn.'cSddr MEJI*prepolymer.

The dispersions of the mixtures are brittle dispersions in the case of the copolymers made of acrylic acid esters and soft, sticky dispersions in the case of the dispersions made of polyacrylate.

Depending on the mixing ratio when different dispersions are present, the properties the product should have before and after curing can be adjusted. For example, a product with BM-2 according to recipe example 2 is not very sticky before curing and has a stable shape after curing.

A product containing BM-3 according to formulation example 3, on the other hand, is more sticky before curing and more flexible after curing.

It should also be noted that up to 30% by weight of water can be added to recipe examples 1 to 4 in addition to the water that is already present in the dispersion. The other components are then reduced proportionately by this water content. If the water content is more than 15% by weight on average, the adhesive properties deteriorate noticeably, making the shapes or structures more unstable, i.e. tending to crumble at the edges.

An anionic surfactant can also be added to the binder as an additive to ensure better wetting.

The invention will be explained in more detail using examples of use (P-X to P-6). Here, molds, models, or objects made from mixtures of the binding agent with loose solids are filled, formed or modeled and then cured.

Example of use (frame example/PX) :

5-98 wt% solids,

2-95 wt% binder,

0-20 wt% colorants and/or other additives.

Example of use 1 (plastic moldings/P-1) :

100g of coarse sand is mixed with 4g of binding agent mixture according to BM recipe example 2 and placed in a mold. The mass is then hardened in a microwave oven for about 3 minutes at 600 watts. After hardening, the molded body can be removed from the mold. Inadvertently exceeding the energy supply time in a microwave oven usually has no negative effects on the hardened molded body. The finer the grain of the sand or other solid used, the sharper and more precise the contours can be. Excellent results can also be achieved in this example if, for example, only 50g of sand is used as a base instead of 100g of sand.

Application example 2 (light body/P-2) :

Flaky, fibrous, light and/or cotton-like material based on silicate is mixed into the binding agent in a ratio of 1:1 according to BM recipe example 3. This mixture of the binding agent with loose fibrous solids is hardened after about 1 minute of energy input in the microwave at about 600 ⁰ C. The resulting and hardened product is as light as a feather. To achieve an optical marble effect, colorants can be stirred into the not yet hardened mixture.

Example of use 3 (moldable mass/P-3) :

A combination of different solids, such as 50g of cellulose fibers and 15g of hollow microspheres are mixed with 150g of the binding agent according to BM recipe example 3. The resulting kneadable mass feels very pleasant and dry, swells slightly during heat treatment in the microwave and can be removed from the microwave and demolded after just 1 to 2 minutes. The products obtained in this way are soft but stable and feel a little more compact than Styrofoam. They can also float in liquid media for weeks.

Application example 4 (sand body/P-4) :

Sand blocks are produced for playing in the sandpit. To do this, 250 g of fine, non-impregnated sand and around 20 ml of liquid binding agent (according to BM recipe example 3) are mixed together. The resulting mixture is pressed into molds and immediately turned out. The sand bodies are dry to the touch after around 10 to 20 minutes. They are solid, but not hardened; they can be crumbled or trampled. Children can use the blocks or other bodies made with them to build excellent sand castles or other sand constructions. Such sand bodies can also be hardened using microwave energy, which makes the sand blocks more stable and more dimensionally stable.

Usage example 5 (wooden body/P-5) :

2 parts of wood sawdust and 5 parts of the liquid binding agent are mixed or blended according to BM recipe example 3. Structures made from the mixture are solid after about 2 minutes of microwave treatment at 600 watts. However, it is important to note that if the energy supply is too long or too high, the sawdust may glow.

Mixtures from the application examples PX to P-5 produce moldable and partially kneadable masses for modeling, crafting and decorating before hardening, as are often used in the hobby sector. Figures, other plastic representations, model bodies, jewelry, relief images, holders and holders for flowers, candles or the like can be made.

These malleable masses can also be used in the fields of industrial design and art to produce prototypes, models or arts and crafts articles or everyday objects of all kinds.

Usage example 6 (paint/P-6) :

In this example, the mixture of the binder with loose solids has a rather pasty or viscous to liquid character and can be used as a three-dimensional

Paint can be described as three-dimensional paint. Three-dimensional paint is understood to be a mass that can be applied with a brush or spatula or through nozzles or tubes, e.g. on a plastic bottle, and which, due to its consistency and solid particles, enables the creation of a third dimension protruding from the plane of the medium.

150g of polyacrylate, a component of BM formulations 2 and 3, is mixed with 8g of hollow microspheres and 14g of cellulose fibers, as well as small amounts of mica. The resulting paint can be applied to textiles or other substrates, to paper and to the surfaces of any object.

This liquid mixture of binding agent and loose solids can be applied in a controlled manner to various textiles or other surfaces using a flexible plastic bottle with a dosing tip attached. After just 3 minutes of exposure to a microwave oven at around 600 watts, the paint is firmly bonded to the textiles and cannot be washed out even after repeated use.

It has been shown that cured molds or models produced according to the above examples do not dissolve in water and therefore also have a high level of weather resistance.

Mixtures of the binding agent according to the invention with loose solids such as wood or stone powder can also be used for repairs and for repair work on wood or stone. The advantage here is that the exact color of the object to be repaired can be adjusted by adding dyes or pigments. The desired consistency of the mixture can also be easily adjusted by varying the binding agent content.

Since the binders according to the invention have good adhesive properties, they are also suitable as "adhesives".

10

This can also be used to fix paper or napkins to objects that have not yet hardened, or the binding agent alone can be used to fix such materials to a wide variety of surfaces.

Dried leaves, flowers or grasses can also be fixed to non-hardened surfaces in this way and then coated or sealed with the binding agent. To seal the leaves or grasses, the binding agent can be painted over in crystal clear or colored form. In this case, the clear or colored binding agent should be an acrylic paint that can be used to paint or coat a wide variety of objects.

The firmness of the uncured mass or the overall mixture can usually be adjusted to the desired consistency by adding water and mixing thoroughly.

Claims (9)

1. Binder for loose solids, powder, granules, flakes or in chip form, in particular for sand, such as natural sand or decorative sand, for chippings, kaolin, fine gravel, for hollow spheres, such as hollow microspheres made of glass or plastic, for metals or various plastics, for organic biomaterials, such as coffee powder, coffee grounds, wood chips or wood dust, fiber materials, textiles and/or for other fibrous or cotton-like materials, pure or mixed with one another, characterized in that it is a plastic dispersion based on acrylate or urethane. 2. Binder according to claim 1, characterized in that the acrylate-based plastic dispersion is a dispersion of a copolymer of acrylic acid esters, a polyacrylate or a mixture thereof. 3. Binder according to claim 1 or 2, characterized in that the plastic dispersion is an aqueous dispersion and that the solids content of plastic particles in the dispersion is between 20 and 50 wt.%. 4. Binder according to one of the preceding claims, characterized in that it contains pigments or dyes as colorants and that the colorant content does not exceed 10% by weight. 5. Binder according to one of the preceding claims, characterized in that it
70-100 wt.% plastic dispersion
0-10 wt.% colorant
0-30 wt.% other additives. 6. Binders according to one of the preceding claims and loose solids as a kneadable or moldable mass for molds, models or any objects. 7. Binders with loose solids, as a liquid or pasty three-dimensional painting medium for painting textiles, surfaces of objects, paper or other surfaces. 8. Binders with loose solids, where
5-98 wt% solids,
2-95 wt% binder,
0-20 wt.% colorants and/or other additives are mixed together. 9. Binder or a binder mixture with loose solids, whereby the strength of the uncured mass or of the total mixture is adjusted to the desired consistency by adding water.