DESCRIPTION

Title: Ready-to-use joint and/or bonding composition

The present invention relates to a ready-to-use joint and/or bonding composition, based on a particulate component and an organic binder comprising both an alkyd resin and a film-forming polymer different from an alkyd resin.

Ready-to-use tile grout compositions are pastes mainly based on mineral particles, usually sand, a polymer binder and water. The polymer binder is generally a thermoplastic and/or elastomeric polymer which is in the form of a latex (aqueous emulsion). The curing of such a ready-to-use tile joint composition is essentially done by evaporation of the aqueous solvent and coalescence of the latex particles.

Ready-to-use joint compositions - such as hydraulic binder-based joint compositions - are spread using a spatula or rubber squeegee over the entire tiled surface, so as to make the composition in the spaces between the tiles and at the same time scrape off the excess material. This operation leaves a fairly thin film of grout composition on the surface of the tiles. This unsightly film must then be removed by wiping.

In the case of the ready-to-use joint compositions marketed by the Applicant, this thin film on the surface of the tiles proved difficult to remove after only a few minutes of drying. This difficulty in wiping is attributed to the fact that the polymeric organic binder quickly forms, by drying and coalescence of the latex particles, a polymer film which adheres strongly to the surface of the tiles and can no longer be removed by simple wiping with with a damp sponge. This same technical problem arises to a lesser extent for the compositions used to bond the tiles and the plates for facades, or even for the mastics.

This type of ready-to-use joint and/or bonding composition therefore requires almost immediate wiping of the residual film, which requires great speed and dexterity from the applicator.

The object of the present invention is to provide a ready-to-use joint and/or bonding composition which can be wiped off more easily and longer after application, without the mechanical properties of the hardened joints being degraded.

This goal was achieved by adding an alkyd resin to the known joint and/or bonding composition.

The Applicant has in fact found, surprisingly, that the addition of a few percent by weight of alkyd resin to a tile joint composition made it possible to significantly extend the “open” time of the composition. The elongation observed is between a few minutes and several tens of minutes depending on the quantity of alkyd resin added. The thin residual film of grouting composition on the surface of the tiling tiles can thus be removed by simply wiping with a damp sponge up to approximately 30 minutes after application. This considerably facilitates the application because the operator can thus fill the joints of much larger tiled areas without worrying about the immediate wiping of the residual film.

The alkyd resin, although a reactive component, need not be added to the composition immediately before use. In other words, the joint and/or bonding composition of the present invention advantageously remains a single-component composition and does not become a two-component composition, which is more difficult to use.

The replacement of a significant part of the polymer binder of a joint and/or bonding composition by an alkyd resin also results in a reduction in the production cost of the composition. Indeed, alkyd resins are generally less expensive than latexes of organic polymers such as commonly used acrylic, styrene-acrylic or polyurethane latexes.

Partial replacement of the usual polymer binder with an alkyd resin also advantageously results in a reduction in the amount of coalescing agent, a volatile organic compound (VOC) frequently present in latexes to reduce the minimum film formation temperature ( MFFT, from English minimum film temperature training).

Finally, the Applicant has found that the addition of an alkyd resin to a ready-to-use gasket composition does not result in a degradation of the mechanical properties of the hardened gasket material. This could be due to the phenomenon of drying of the oily component of the alkyd resin.

The subject of the present application is therefore a paste-like, ready-to-use joint and/or bonding composition, comprising

(a) a particulate component formed from fillers and/or pigments,

(b) an organic binder comprising

- a first film-forming polymer which is a alkyd resin, and

- a second film-forming polymer, different from an alkyd resin, and

(c) water.

Advantageously, the organic binder is free of non-film-forming organic polymers and then consists of a first film-forming polymer which is an alkyd resin and a second film-forming polymer other than an alkyd resin.

Film-forming polymer is understood to mean a polymer whose minimum film formation temperature (MFFT) is lower than 20°C, preferably lower than 15°C and in particular lower than 10°C.

The composition of the present invention has a pasty consistency. It therefore does not flow freely when applied to the tiled area, but has a plasticity that allows it to easily enter the spaces between the tiles using a spatula or squeegee.

The composition of the present invention is a ready-to-use single-component composition. This means that it is not necessary to add another component, for example water or a reagent, and that it contains all the ingredients necessary for the formation of durable tile joints with mechanical resistance. compatible with the intended use.

The foregoing does not exclude that, in certain embodiments, the composition reacts with components of the atmosphere after its placement in the joints. This is the case, for example, when the alkyd resin contains drying oils containing ethylenic unsaturations which react slowly with the oxygen (O2) in the air.

The composition of the present invention can be a composition for forming joints between floor tiles or between facade panels. It can also be used to glue tiling tiles or facade panels to the support. The composition of the present invention can also be a putty. It is preferably a tile joint composition.

The first component of the composition of the present invention is a particulate component formed from fillers and/or pigments.

The fillers are preferably mineral fillers. Their main function is to give consistency to the composition and reduce its costs.

The mineral fillers are for example chosen from the group formed by sand, crushed dolomite, crushed limestone rock, crushed barite and crushed marble. The mineral fillers preferably have dimensions less than 4 mm. They preferably comprise sand.

The term "sand" means alluvial mineral aggregates having dimensions less than 4 mm. Preferably use silica sand.

Pigments include organic and inorganic pigments. They preferably have dimensions similar to those of the fillers. Their function is mainly to color the joint.

The content of particulate component formed of fillers and/or pigments of the ready-to-use composition is advantageously between 70 and 85%, expressed by dry weight relative to the total weight of the composition.

The particulate component is advantageously composed of particles having a size (determined by sieving) of between 70 μm and 3.0 mm, preferably between 75 μm and 1.0 mm and in particular between 80 μm and 500 μm. The particle size of the particulate component is ideally between 90 µm and 300 µm.

The second component of the composition of the present invention is an organic binder formed from at least two types of polymers, namely a film-forming alkyd resin and another film-forming polymer, different from an alkyd resin.

These two types of film-forming polymers are preferably introduced and present in the composition in the form of aqueous dispersions, also called latexes.

Component (b) of the composition is therefore advantageously a mixture of an alkyd resin latex and a latex of another film-forming synthetic organic polymer.

The amount of organic binder, expressed as dry weight of organic binder relative to the total weight of the composition, is advantageously between 4 and 15%, preferably between 5 and 11%, and in particular between 6 and 10%.

Finally, the water content of the composition is generally between 5 and 20% by weight relative to the total weight of the composition, this aqueous fraction including the water of the latexes of the first and second film-forming polymers of the organic binder.

Alkyd resins are thermosetting polyesters modified by the addition of fatty acids generally in the form of oil (triglycerides). The oil content, also known as the oil length of an alkyd resin, can range from about 30% to about 70%, thus alkyd resins are classified into short oil, medium oil and long oil resins.

The alkyd resin used in the present invention preferably has an oil length between 35 and 55%.

The hardening of alkyd resins is done by esterification, but also by drying when the oils contain unsaturated fatty chains. Siccativation is a known phenomenon that includes the oxidation of ethylenic unsaturations with oxygen in the air and the formation of covalent bonds between fatty chains. The oils capable of such a polymerization/crosslinking reaction are called “drying oils”, this term encompassing in the present application the oils

driers with conjugated double bonds and semi-drying oils with non-conjugated double bonds.

Advantageously, an alkyd resin based on soybean oil will be used.

The alkyd resin may additionally contain a drying agent whose function is to accelerate the drying reaction.

Aqueous dispersions of alkyd resins are known as such and their preparation is described for example in applications WO2001 092378. WO2013/056162 or EP 2 395 058. They are commercially available, for example under the name URADIL AZ-765 ( DSM), Synaqua 2080 from Arkema, InoKem 1105 from Ecoat.

The alkyd resin (first film-forming polymer of the organic binder) is always used in combination with a second film-forming polymer which is not an alkyd resin. Like the alkyd resin, this second film-forming polymer is preferably an aqueous dispersion, in other words a latex.

The chemical nature of this second film-forming polymer is not decisive and this second film-forming polymer can be chosen from a wide variety of film-forming organic polymers.

Mention may be made, by way of examples of film-forming polymers other than alkyd resins, of those chosen from the group formed by acrylic polymers, styrene-acrylic polymers and polyurethanes.

Preferably, an acrylic polymer, in particular an acrylic latex, will be used.

To have a significant effect on the open time of the tile grout composition of the present invention, the alkyd resin should be present in a concentration at least equal to 1% by weight, preferably at least equal to 2% by weight and in particular at least equal to 3% by weight, expressed as dry weight of resin relative to the total weight of the tile joint composition. Its concentration generally does not exceed 10% by weight, and is preferably less than 9% by weight, in particular less than 8% by dry weight relative to the total weight of the ready-to-use composition.

The weight ratio of the alkyd resin to the second film-forming polymer is advantageously between 20/80 and 80/20, preferably

between 30/70 and 70/30, more preferably between 40/60 and 60/40, expressed as dry matter of each of the components.

The compositions of the present invention may also contain one or more additives chosen in particular from coalescing agents, dispersing agents, thickening agents, coloring agents and preservatives (biocides).

These additives preferably do not represent more than 4% by weight of the tile joint composition, in particular at most 3% by weight.

Example

Two ready-to-use tile grout compositions A and B are prepared from the ingredients in Table 1

[Table 1]

(1) URADIL AZ-765 from DSM emulsion with 53% dry extract

(2) PLIOTEC PA05 from Omnova Solutions, acrylic emulsion with 48% dry extract

(3) Water-insoluble microcrystalline cellulose

(4) dipropylene glycol butyl ether (coalescent)

(5) dipropylene glycol methyl ether (coalescent)

(6) Aqueous Defoamer Silicone Emulsion

(7) antifungal/antialgae

(8) preservative (bacteria, fungi and yeasts)

(9) non-ionic polyether-urethane, combination thickener

(10) dispersing agent (polyelectrolyte)

(11) 2-amino-2-methyl-1-propanol with 10% water

The two compositions A and B are used to fill the joints of a square made of sixteen tiles using a rubber squeegee.

After five minutes, wipe a first quarter of the square with a damp sponge. Then a second shift after 10 minutes, a third shift after 20 minutes and the last shift after a total drying period of 30 minutes.

Figure 1 shows the result obtained with comparative composition A. It can be seen that after only five minutes of drying (upper left quarter) the thin whitish film of joint composition formed on the surface of the tiles is not removed by simple wiping with a damp sponge.

On the other hand, as shown in Figure 2 obtained with composition B according to the invention, even after a total drying time of 30 minutes (lower right quarter), the surface of the tiling tiles cleaned with a damp sponge is perfectly clean.

The presence of approximately 3 - 4% by dry weight of alkyd resin dramatically retards the drying and coalescence of the latexes and advantageously prolongst the open time of the ready-to-use joint compound.

CLAIMS

1. Pasty, ready-to-use joint and/or bonding composition, comprising

(a) a particulate component formed from fillers and/or pigments,

(b) an organic binder comprising

- a first film-forming polymer which is an alkyd resin, and

- a second film-forming polymer, different from an alkyd resin,

(c) water.

2. Composition according to claim 1, in which the first and second film-forming polymers are present in the form of aqueous dispersions.

3. Composition according to claim 1 or 2, in which the content of particulate component formed from fillers and/or pigments is between 70 and 85%, expressed by dry weight relative to the total weight of the composition.

4. Composition according to one of the preceding claims, in which the fillers are mineral fillers preferably chosen from the group formed by sand, crushed dolomite, crushed limestone rock, crushed barite and crushed marble.

5. Composition according to one of the preceding claims, in which the amount of organic binder is between 4 and 15%, expressed as dry weight of organic binder based on the total weight of the composition.

6. Composition according to one of the preceding claims, in which the water content is between 5 and 20% by weight relative to the total weight of the composition.

7. Composition according to any one of the preceding claims, in which the alkyd resin has an oil length of between 35 and 55%.

8. A composition according to any preceding claim, wherein the oil of the alkyd resin is a drying oil.

9. Composition according to claim 8, characterized in that the oil of the alkyd resin is soybean oil.

10. Composition according to any one of the preceding claims, in which the alkyd resin is present in a concentration at least equal to 1% by weight, preferably at least equal to 2% by weight and in particular at least equal to 3% by weight, expressed as dry weight of resin relative to the total weight of the tiling joint composition, the concentration of the alkyd resin not exceeding 10% by dry weight relative to the total weight of the ready-to-use composition.

11. Composition according to one of the preceding claims, in which the second film-forming polymer, other than an alkyd resin, is chosen from the group formed by acrylic polymers, styrene-acrylic polymers and polyurethanes.

12. Composition according to one of the preceding claims, in which the second film-forming polymer, other than an alkyd resin, is an acrylic polymer.

13. Composition according to one of the preceding claims, in which the ratio by weight of the alkyd resin to the second film-forming polymer is between 20/80 and 80/20, preferably between 30/70 and 70/30, more preferably between 40/60 and 60/40, expressed as dry matter of each of the components.

14. Composition according to any one of the preceding claims, characterized in that it also contains one or more additives chosen in particular from coalescing agents, dispersing agents, thickening agents, coloring agents, preservatives (biocides ).

15. Composition according to any one of the preceding claims, characterized in that it is a tile joint composition.