ES2289916B1 - COLLOIDAL DISPERSION OF CERAMIC PIGMENTS. - Google Patents

Abstract

Colloidal dispersion of ceramic pigments. The present invention relates to a colloidal dispersion of ceramic pigments characterized in that it comprises: - at least one ceramic pigment, - at least one non-polar solvent, - a solids content of between 20% and 80% by weight and - a viscosity between 5 and 100 cp, said dispersion having an average colloidal particle size between 0.3 and 2 microns; as well as its use in the field of decoration, especially in ceramic products, glass, and metal, as well as its use in posters, posters and panels for outdoor use.

Description

Colloidal dispersion of ceramic pigments.

Technical Field of the Invention

The scope of these dispersions covers any field of decoration, especially in products ceramics, glass, and metal, as well as its use in posters, posters and  panels for outdoor use, where ceramic pigments they can provide greater resistance to light exposure than the organic pigments currently used.

State of the art prior to the invention

The dispersion of pigments in solvents has It has been a necessity since time immemorial, from the moment they were used in any decorating technique or for contribute pigment to a dough to color (plastic, cement, paper, ceramics. etc.).

Two are the main problems encountered So far and to which the present invention provides a solution:

The dispersions of concentrates of color, with high solids content, has a high viscosity, especially the smaller the particle size (by the specific surface increase).

Obtaining dispersions of pigments with very low viscosity (µ <20 cp) have strong stability, syneresis and sedimentation problems, especially when the pigments are inorganic and therefore they have high densities (4 to 8 gr./cc.).

Thus, the present invention relates to dispersions of ceramic pigments with high solids content and very low viscosities (10-20 cp), susceptible of being used as color concentrates for mass contribution to Coloring, such as plastics or MasterBach, decoration systems by high resolution screen printing (fabrics of more than 180 meshes / cm), flexographic rollers, and for their special characteristics They are also susceptible to being used in InkJet technology.

The use of pigment dispersions ceramic, object of the present application, by technology InkJet, have been treated in previous patents, for the decoration of ceramic and glass products from the first attempts to steal Bosch (P 3434334.2 (1984)) and especially since that in April 1987, W. Roberts in his presentation "Methods of decoration for the future "before the convention" Institute of Ceramics Convention ", published in 1988 by Journal Gr.Cer.Soc. 87 (1) 1988 and by L'Industrie Cérammique n ° 827, 5/88, 307-311, speak clearly of the possibilities and the limitations of the decoration of ceramic products by InkJet technology.

Subsequently, several patents have gone providing different approaches to problem solving, or they have merely raised working hypotheses, until reaching the level of knowledge necessary for the decoration currently industrial ceramic products using InkJet sea technology a reality through the use of InkJet (KeraJet) machines and suitable inks (Ferro Corporation).

For example, WO9215648, EP0573476, US5407474, GB2268505, requested by BRITISH CERAMIC RES LTD (CROOKS, AIREY & BRETT) about "Ink jet printer ink for printing on ceramics or glass ", published on 1995-04-18 and number of priority: GB19910004171 19910227; refers to "A pigmented usable ink in an ink jet printer in which the maximum particle size of the pigment is sufficiently small not to block the nozzles or the filters of the printer and the particle size range is sufficiently narrow for the ink to have a low viscosity for the printer to operate. The ink is particularly suited for printing on ceramics or glass ".

Additionally, other patents (Crooks Mark E., US 5,407,474 (1994)) propose the use of pigment suspensions of particle size between 0.2 and 2 microns (0.2 x 10-6 m and 2 x 10-6 m), suffering from major drawbacks, namely: the minimum pigment size without it breaking its reticulum and solving two problems fundamentals inherent to InkJet technology: the stability of the suspension and abrasion over the injector holes, which every day they tend to get smaller to reach levels resolution offered by other techniques (paper printing, UV inks, etc.).

On the other hand, Alan Atkinson (GB-2,274,847 (1993)) suggests the possibility of use, for the InkJet decoration of ceramic products, a pigment formed by atomization and subsequent calcination of a colloidal solution or dispersion thereof, obtaining particles of pigment between 0.2 and 0.4 microns (0.2 x 10-6 m and 0.4 x 10-6 m). This patent is very generic and does not provide results different from those easily attainable by grinding by dry route (Jet Mill), that is, products similar to those obtained by calcination of traditional formulations.

Additionally, Maasaichi Murota et al. (WO-02/02347 A1 (2000)) propose the use of a dispersion of ceramic agglomerates of nanoparticles as print media coating (paper and other surfaces) without specifying the use of this principle in the inks.

Also US-5,273,575 (1992) of Pierre de Sant Romain talks about the use of soluble salts in polar solvents of Zr, Cr, Mn, Co, Fe. Although it does not solve the problem of obtaining four-color, also presents the problem of penetration that in an uncontrolled way have the  inks soluble in polar solvents or in water, depending on residual moisture, temperature and enameled surface of the piece to decorate. Later Sant Romain (EP-0.572.314-A1) (1993) resolves in part of the problem necessary for the formation of titanates Cr and Ni yellows in the presence of Sb, Ce or W.

It has been found that the presence of Titanium in enamels negatively affects development and, especially, to the color purity of Cyan, magenta and black, while the use of this additive causes a coloration yellowing of the enamels after cooking, which affects negatively to the aesthetic effects of the final product, in addition to a different behavior in the development of enamel color and inks dependent on the different degree of solubilization of the titanium and the different cooking conditions.

To solve some of the problems previously described, the applicant filed the ES 2 patent 209 634 as of 2002-09-19 and published on 2004-06-16 with the title of "New yellow ink for decorating items ceramic and glass using Inkjet technology "which claimed, among other matters, the use of titanium oxide in solid state, introduced as microdispersion in a non-solvent polar. This application is incorporated herein as reference.

Since the mere introduction of said additive Titanium to get a yellow ink, gives rise to numerous problems of color development and ink stability, the applicant has continued to investigate in order to obtain some inks exempt from such inconveniences.

Brief description of the figures

Figure 1 shows the loss of value chromatic in b * (yellow component) of the pigment when the size Average of the particles is less than 1 micron (1 x 10-6) m).

Figure 2 shows the relationship between the color capacity and particle size; in the process of particle size reduction, the energy applied obviously modify the surface penetration of the inks by application of a "fixative" before the application of inks

On the other hand, several authors have suggested the use of metal salts to obtain yellow colors on ceramic support, but through the use of complex techniques "traditional" application of pigments / dyes (Grazziano Vignali, US-6,132,672 (1997)), EP-0.940.379 A1 (1999)).

Some author has patented the use of salts soluble metals for use in technical products not decorative to be applied on glass (Boaz US 5,091,003 (1990)), while other authors are have referred to the use of metal carboxylates in technology InkJet as welding products (Enokida Kiyomi JP-63.278.983 (1988)), or as binders in inks of textile printing (Paul Held Robert US-5,853,861 (1998)), or as conductive electrodes in microelectronics (Shaikh Aziz US-5,897,912 (1999)) or semiconductor layers (Oyama Hideaky and others US-5,920,798 (1999)), may or may not use InkJet technology as the basis of your application, but in any case outside of any relationship with the object of the present invention and its scope.

Application WO 00151573-A1 of The applicant himself refers to a set of inks that allows the obtaining the four basic colors of the CMYK four-color process (Cyan Magenta Yellow and Black) and, by mixing the separate prints of individual inks, get shades intermediates such as green (by yellow / Cyan combination), or oranges (by combination of yellow and magenta). That request finds despite the results disclosed in it, important difficulties in getting an acceptable yellow ink in this technical field.

The formation of the precise yellow color of the use of enamels to which oxides of titanium in order to incorporate the crystalline phase Rutile-anatase granulometric distribution obtained, modification that affects the coloring power and values chromatic pigment.

Figures 3 and 4 show the mechanism of performance of dispersants used as low weight polymers molecular and multiple functional groups that produce a stabilization by steric impediments.

Figures 6 and 7 show how at casualties velocities (1500 rpm), the average particle size decreases with the increase in the size of the grinding media, while in the case of high speeds (3500 r.p.m.) the situation is radically different and more in line with expectations.

Figure 8 shows the reflectance of a sample with 80% solids, perfectly stable,

Figure 9 shows the behavior of a Sample with a grinding energy of 1 Kwh.

Figure 10 shows the result of the analysis of the same formulation as in figure 9, but ground with a Total applied energy of 1.5 Kwh.

Figure 11 shows the results obtained by InkJet application of the dispersions obtained according to the examples.

Inks appear from left to right obtained yellow, blue, black, magenta and green along with the maximum intensity obtained with inks based on WO-00151573 A1 of the applicant, shown in the piece located at the right end of the figure.

Description of the invention

The present invention relates to a colloidal dispersion of ceramic pigments characterized by understands:

- at least one ceramic pigment,

- at least one solvent non-polar,

- with a solids content of between 20% in weight, and 80% by weight,

- a viscosity between 5 and 100 cp,

said dispersion having an average colloidal particle size between 0.3 and 2 microns (0.3 x 10-6 m
2 x 10-6 m).

These dispersions are characterized essentially because they allow to reach very high concentrations in solids, preferably between 45% and 80% and more preferably even between 60% and 80% by weight, in solvents not polar.

The viscosity is preferably less than 20 cp. and the densities of solids are preferably relatively high (4-6 gr / cm3).

According to particular embodiments of the invention, said pigments are selected from pigments vanadium-zirconium-silica blues (such as PB-71, which refers to the "Color Index Pigment Blue 71 "), cobalt-alumina (such as PB-72) and of cobalt-silica (such as PB-73).

According to additional particular embodiments of the invention, said pigments are selected from magenta iron-zirconium-silica (such as PR-232) and chromium-tin-calcium (such as PR-233).

According to additional particular embodiments of the invention, said pigments are selected from pigments yellows of praseodymium-zirconium-silica (such as PY-159), nickel-titanium-antimony (such as PY-53), and chrome-titanium-antimony (such as PBr-24).

According to additional particular embodiments of the invention, said pigments are selected from pigments blacks of cobalt-nickel-iron-chromium (such as PBk-27).

According to additional particular embodiments of the invention, said pigments are selected from pigments chrome-alumina greens and chrome-silica

According to additional particular embodiments of the invention, said pigments are selected from pigments brown iron-chromium-zinc (such as PBr-).

Ceramic pigments suitable for dispersions object of the present invention are so Especially preferred, ceramic pigments, manufactured by Ferro Corporation and its subsidiaries, preferably and in a manner not exclusive:

Blues :

Vanadium Zirconium Silica (PB-71)

Cobalt Alumina (PB-72)

Cobalt Silica (PB-73).

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Magenta :

Iron Zirconium Silica (PR-232)

Chrome Tin Calcium (PR-233)

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Yellows :

Praseodymium Zirconium Silica (PY-159)

Nickel Titanium Antimony (PY-53)

Chrome Titanium Antimony (PBr-24)

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Blacks :

Cobalt Nickel Iron Chrome (PBk-27)

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Greens :

Alumina Chrome, Silica Chrome

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Brown :

Chrome Zinc Iron (PBr-33)

All these pigments are known for for a long time and are likely to be able to obtain, for mixture, a wide range of colors, just as the use of colors that met the properties of the basic colors of the four-color, with the special contribution of brown colors and greens to complement the combinations magenta-yellow and blue yellow.

The non-polar solvent is selected from one or more aliphatic hydrocarbons, dearomatized isoparaffinic hydrocarbons, glycol ether, esters, ethers, isoparaffinic hydrocarbons, aromatic hydrocarbons with terminations of OH groups, mixture of aliphatic hydrocarbons and diisopropylnaphthalene isomers, normal hydrocarbon mixture-, iso-, cycloparaffins and diisopropylnaphthalene isomers, mixture of  normal hydrocarbons-, iso-, cycloparaffins and isomers of monoisopropylnaphthalene, mixture of diisopropylbiphenyl isomers, mixture of monoisopropylnaphthalene isomers and diisopropylnaphthalene, ketones, such as 2,6,8-trimethyl-4-nonanone, an alkyl derivative of nitrogen heterocyclic compound, aromatic hydrocarbons with ester group terminations, alkyl carbonate, dimethylsulfoxide, alkyl acid phosphate, and combinations thereof.

Concrete examples of non-polar solvents are those belonging to the families indicated below, with mention of some of the references used and the manufacturer or  provider of these:

dearomatized aliphatic and isoparaffinic hydrocarbons :

EXXSOL

D110 EXXON

EXXSOL

D120 EXXON

EXXSOL

D140 EXXON

VARSOL

D110 EXXON

VARSOL

D120 EXXON

VARSOL

D140 EXXON

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Glycol ether :

2- (2-ethylhexyloxy) ethanol

ALDRICH

Butildiglimaldiglima

CLARIANT

POLYGLYME

Dow

TETRAGLYME

Dow

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Ester :

COASOL

CHEMOXY

DBE

DUPONT

DBE-3

DUPONT

DBE-6

DUPONT

EXXATE 1000

EXXON

bis (2-ethylhexyl) adipate

MERCK / BAYER

bis (2-ethylhexyl} sebacate

MERCK

Butildiglimalo Lactate

ALDRICH

DiButildiglimalsebacato

ALDRICH

Triethyl citrate

MERCK

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Aromatic hydrocarbons with terminations of OH groups :

Wheels LK-7020

RKS

Wheels LK-5251

RKS

Wheels LK-6030

RKS

Wheels RT-4332

RKS

Wheels RT-4030

RKS

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Isoparaffinic hydrocarbons :

ISOPAR M

EXXON

ISOPAR P

EXXON

ISOPAR V

EXXON

NORPAR 15

EXXON

Other hydrocarbons can also be served with various structures and functional groups, such as those indicated at continuation:

100

101

The colloidal dispersion of ceramic pigments It may also comprise one more dispersant. Substances used  as dispersants they also act as humectants and are therefore both, also used for the purpose of also taking advantage of their moisturizing action Consequently, every time in the present memory appears the term dispersant, is referring simultaneously to "humectant" and all substances named as dispersants, they are equally moisturizing.

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Such dispersants are selected from: alkylammonium salts of a polycarboxylic acid, acid salts polyamine amide polycarboxylic, alkylammonium salts of a unsaturated fatty acid, combination of anionic surfactants and amphoteric, salts of a polymer with acid groups, acid ester hydroxy functional carboxylic acid copolymer, acrylic copolymer, salts of a hydroxyalkylamine of a block copolymer, polymer dispersants, polyurethane modified unsaturated carboxylic acid modified with groups hydroxyl, salts of acid esters and unsaturated polyamide, polyether aliphatic with modified acid and polyether groups. All substances named in this paragraph are equally moisturizing, as explained above.

The colloidal dispersion of ceramic pigments according to the invention preferably comprises a distribution of particle sizes between 0.6 and 1 microns (0.6 x 10 - 6 m and 1 x 10-6 m).

The dispersion has a resulting viscosity at the application temperature preferably between 9 to 20 cp.

The colloidal dispersion of ceramic pigments it has a density difference between solids and the solvent preferably of at least 3 g / cc.

The colloidal dispersion of ceramic pigments according to the invention it has a surface tension with values preferably between 20 and 50 dynes / cm.

One of the limitations in the stability of these dispersions are governed by the degree of sedimentation, which should be avoided and its relation to the particle size, the density of this and the viscosity of the dispersing medium and is by this the critical phase of this development, is defined by the tendency of dispersions of solids to settle, sedimentation whose speed is defined by the law of Stoke:

V = d2 \ \ Delta \ rho \ g \ / \ 18 \ \ mu

where "d" is the average diameter of the particle, "\ Delta \ rho" is the difference of densities between the solvent and the solid and "µ" is the viscosity of solvent

So it would be clear enough that a very small particle size and high viscosity would clearly favor the stability of the dispersion.

The present invention thus constitutes a important novelty, since the objective is to obtain dispersions stable with very low viscosity of order 10-20 centi poises (cp), a high solids content (between 20 and 80%) and a difference in densities between the dispersed phase and the dispersant of at least 3 gr./cc.

On the other hand, the influence of the variation of the particle size and therefore the particle size, in the chromatic performance, both for destruction of the reticulum crystalline, as by increased reactivity and dissolution in the vitreous phase of enamel is especially critical in applications of pigmented inks for ceramic use, both in monocoction as in bicoction or third fire, so it has conducted an exhaustive study of these phenomena, which show the delicate process of dispersion by micro-nano  grinding.

In this way, this study has allowed to limit the maximum grinding grade applicable to ceramic pigments without that there is a loss of intensity greater than desirable and limit also desirable particle size distributions such as "maxims" in the development of nano and micro pigments to which Mention was made in the previous point.

Thus, the grinding of a PrZrSi pigment (PY-159), internally referenced in Ferro as B-0473, with an average particle size of 6 microns (6 x 10-6 m), at resulting granulometries expressed in the following table (table 1)

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TABLE 1

one

Chromatic values correspond (once homogenized, applied and cooked, a mixture of transparent enamel of porous monocoction and 5% of the ground and dry pigment), whose results are indicated in the
table-2:

TABLE 2

2

These results, expressed graphically (figure 1), show the considerable loss of color value in b * (yellow component) of the pigment when the average size is less than 1 micron (1 x 10-6 m). This relationship between the color capacity and particle size is sufficiently illustrated in figure 2.

For this reason, the choice of additives and solvents, as well as dispersants and size distribution of final particle, are critical phases, being used, by the non-polar characteristics of solvents used, a stabilization by steric impediments by low molecular weight polymers and multiple functional groups, whose mechanism of action is reflected in the figures (figures 3 and 4).

So they have been tested as dispersants:

- Alkylammonium salt of an acid polycarboxylic (Anti-Terra-203)

- Polyamide amide polycarboxylic acid salt (Anti-Terra-204 / -205)

- Alkylammonium salt of a non-fatty acid saturated (Anti-Terra-206)

- Combination of anionic surfactants and amphoteric (BykOplast LO-100)

- Salt of a polymer with acid groups (Disperbyk-106)

- Hydroxy functional carboxylic acid ester Disperbyk-108

- Copolymer with acid groups (Disperbyk-111)

- Acrylic copolymer Disperbyk-116

- Salt of a hydroxyalkylamine of a copolymer block (Disperbyk-180)

- Polymeric dispersants: (Solsperse 3000, Solsperse 13940, Solsperse 28000, Solsperse 36600, Solsperse 38500)

- Modified polyurethane (Efka-4009, Efka-4010, Efka-4015, Efka-4047)

- Unsaturated carboxylic acid modified with hydroxyl groups (Efka-5207)

- Salts of acid esters and unsaturated polyamide (Efka-5244)

- Modified polyether (Efka-7500)

- Aliphatic polyether with acid groups (Efka-6230).

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The present invention also relates to the use of a colloidal dispersion of pigments as defined, in  A decorating technique.

Such decorating technique can be a product decoration technique selected among products ceramics, glass, metal, signage and panels.

It can also be a decorating technique of ceramic products, selected from monocoction, bicocción and third fire

It can also be a decoration technique of pavements and coverings.

Among the decoration techniques can be cited a technique selected from screen printing, offset gravure e inkjet

The ceramic pigments of the invention are liable to be used in any field of decoration, especially in ceramic products, glass, and metal, as well as in posters, posters and panels for outdoor use, where ceramic pigments can provide greater resistance to light exposure than the organic pigments used currently.

In accordance with the above, all the compositions indicated in table 3 can be considered realization examples and allow to obtain dispersions of ceramic pigments usable in any decoration technique, having been verified its use by InkJet application in a printhead XJ-500 by Xaar Ltd. on material ceramic and on paper.

Embodiments of the invention

The conditions of preparation of dispersions unequivocally define the results of stability and fineness obtained in various test series, as well therefore, using the same initial formulation and the same team of  dispersion, in this case a LabStar Mill from Netzsch, the difference between using grinding media (ZiY microballs) of different sizes (0.4-0.6 mm, 0.5-0.8 and 1.0-1.2 mm) at different stirring speeds, for the same total energy applied, they are extremely different and critical and are illustrated in the figure 5.

More explicitly, at the same energy applied, it is easy to verify that the relationships between the size of average expected particle, is delimited, more by the effects of shear stresses that due to impact at low speeds, while these take on more prominence at high speeds of agitation.

Figures 6 and 7 show that low speeds (1500 rpm), the average particle size decreases with the increase in the size of the grinding media, while in the case of high speeds (3500 r.p.m.) the situation is radically different and more in line with what expected.

So, in the process of size reduction of particle, the applied energy obviously modifies the granulometric distribution obtained, modification that affects the coloring power and the chromatic values of the pigment, having being definitely evidenced in figure 2.

As indicated above, Stoke's law it also says that the sedimentation rate is directly proportional to the square of average particle size e inversely proportional to the viscosity of the medium, so a average particle size reduction of 6.0 microns (6.0 x 10-6 m) (calcined pigment starting size) at a size 0.6 micron particle medium would reduce the speed of sedimentation to the hundredth part, but as already demonstrated, this particle size would provide a coloring power of the pigment considerable minor.

Moreover in the dispersions strongly colored, agglomeration processes are difficult to appreciate, syneresis and sedimentation, and thus, an analyzer has been used optical stability of liquid dispersions (TurbiScan Lab Expert) that allows measurements to be made every 40 microns (40 x 10 - 6) m) along 80 mm of scanner on the measuring cell, with the in order to analyze the transmittance and reflectance of the sample and so by analyzing backscatering (reflectance), characterize the suitability of the dispersions.

In an explanatory way, the figures show the reflectance of a sample with 80% solids, perfectly stable (figure 8), the behavior of a sample with a grinding energy of 1 Kwh (figure 9) and the result of the analysis of the same formulation but ground with total energy 1.5 Kwh applied (figure 10).

In this way multiple trials have been prepared which are reflected in tables 3A and 3B.

TABLE 3A

3

4

5

6

7

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TABLE 3B

8

9

10

eleven

12

13

14

fifteen

16

17

18

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In all cases of composition shown in Table 3, the preparation has followed the following steps:

1. Addition to a capacity vessel Sufficient solvent chosen.

2. Addition of dispersant and / or stabilizer selected.

3. Stirring and homogenization of the mixture by high shear agitator.

4. Adding with agitation of the pigment according to the chosen formulation.

5. Stirring until homogenization of the Mix for a period of time between 30 minutes and 2 hours.

6. Grinding and dispersion by mill microballs in a NetSsch LabStar device, controlling the stirring speed, recirculation flow and energy applied per kilogram of pigment introduced.

7. Determination of physical properties of product resulting from grinding.

8. Filtration by depth filter Sartopure of 5 microns of Sartorius.

9. Stability study through TurbiScan LabExpert

10. Application of the resulting dispersion by Xaar XJ-500 printhead on paper and glazed ceramic support.

11. Cooking ceramic support (for example a tile) and data analysis.

The results can be seen in figure 11 obtained by InkJet application of the dispersions obtained according to The examples cited. In that picture you can see from the left on the right the inks obtained yellow, blue, black, magenta and green together with the maximum intensity obtained with the inks based on WO-00151573 A1 of the applicant, shown in the piece located at the right end of the figure.

Claims (19)

1. A colloidal dispersion of ceramic pigments characterized in that it comprises:

-

to the less a ceramic pigment,

-

to the minus a non-polar solvent,

-

a solids content between 60% and 80% by weight, excluding the value 60% and

-

a viscosity between 5 and 100 cp,

said dispersion having a size colloidal particle medium between 0.3 x 10-6 m and 2 x 10-6 m. 2. A colloidal dispersion of ceramic pigments according to claim 1, characterized in that said pigments are ceramic pigments selected from blue pigments of vanadium-zirconium-silica PB-71, cobalt-alumina PB-72 and cobalt-silica PB-73. 3. A colloidal dispersion of ceramic pigments according to claim 1, characterized in that said pigments are ceramic pigments selected from iron-zirconium-silica magenta PR-232 and chromium-tin-calcium PR-233. 4. A colloidal dispersion of ceramic pigments according to claim 1, characterized in that said pigments are selected from yellow pigments of praseodymium-zirconium-silica PY-159, nickel-titanium-antimony PY-53, and chromium-titanium-antimony PBr-24 . 5. A colloidal dispersion of ceramic pigments according to claim 1, characterized in that said pigments are selected from black cobalt-nickel-iron-chromium pigments PBk-27. 6. A colloidal dispersion of ceramic pigments according to claim 1, characterized in that said pigments are selected from green chromium alumina and chromium silica pigments. 7. A colloidal dispersion of ceramic pigments according to claim 1, characterized in that said pigments are brown iron-chromium-zinc pigments PBr-. A colloidal dispersion of ceramic pigments according to one of claims 1 to 7, characterized in that the non-polar solvent is selected from one or more aliphatic hydrocarbons, dearomatized isoparaffinic hydrocarbons, glycol ether, esters, ethers, isoparaffinic hydrocarbons, aromatic hydrocarbons with terminations of OH groups, mixture of aliphatic hydrocarbons and diisopropylnaphthalene isomers, mixture of normal hydrocarbons-, iso-, cycloparaffins and isomers of diisopropylnaphthalene, mixture of normal hydrocarbons-, iso-, cycloparaffins and isomers of monoisopropylnaphthalene diphenyl, mixture of of isomers of monoisopropylnaphthalene and diisopropylnaphthalene, ketones, an alkyl derivative of nitrogenous heterocyclic compound, aromatic hydrocarbons with terminations of ester groups, alkyl carbonate, dimethylsulfoxide, alkyl acid phosphate, and combinations thereof. 9. A colloidal dispersion of ceramic pigments according to claim 1, characterized in that it comprises one or more dispersants. 10. A colloidal dispersion of ceramic pigments according to one of claims 1 to 8, characterized in that the dispersants are selected from: alkylammonium salts of a polycarboxylic acid, polycarboxylic acid salts of polyamine amides, alkylammonium salts of an unsaturated fatty acid, combination of anionic and amphoteric surfactants, salts of a polymer with acidic groups, hydroxy-functional carboxylic acid ester, copolymer with acidic groups, acrylic copolymer, salts of a hydroxyalkylamine of a block copolymer, polymeric dispersants, modified polyurethane modified unsaturated carboxylic acid with groups hydroxyl, salts of acid esters and unsaturated polyamide, aliphatic polyether with acid groups and modified polyethers. 11. A colloidal dispersion of ceramic pigments according to one of claims 1 to 10, characterized in that it comprises a particle size distribution of between 0.6 x 10-6 m and 1 x 10-6 m. 12. A colloidal dispersion of ceramic pigments according to one of claims 1 to 11, characterized in that it has a resulting viscosity at the application temperature between 9 to 20 cp. 13. A colloidal dispersion of ceramic pigments according to one of claims 1 to 12, characterized in that it has a density difference between the solids and the solvent of at least 3 g / cc. 14. A colloidal dispersion of ceramic pigments according to one of claims 1 to 13, characterized in that it comprises a surface tension with values between 20 and 50 dynes / cm. 15. Use of a colloidal dispersion of pigments defined in any one of the preceding claims in A decorating technique. 16. Use of a colloidal dispersion according to claim 16 in a product decoration technique selected among ceramic products, glass, metal, signage and panels. 17. Use according to claim 16, characterized in that the decoration is a technique of decorating ceramic products, selected from monocoction, bicoction and third fire. 18. Use according to claim 17, characterized in that the decoration is a floor and wall decoration technique. 19. Use according to claim 15, characterized in that the decoration is a technique selected from screen printing, offset gravure and inkjet.