Manufacture of iridescent pigment formulation, iridescent pigment formulation and method for using the same

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to a method for producing a pearl photopigment preparation as a pre-product of a printing ink containing a pearl photopigment.

【0002】

[Conventional technology]

Pearl photopigments are usually commercially available in powder form. In the production of printing inks, pearl light pigments are mixed with a binder solution and, in some cases, conventional printing additives are added to adjust the mixture to the viscosity required for printing. In order to obtain the soft brilliance effect generally possessed by the pearl light pigment of the printing ink, it is necessary to disperse the pearl light pigment in the binder as evenly as possible and let it blend in.

【0003】

High shear forces should basically be avoided in the treatment of pearl photopigments. Therefore, the pearl photopigment must be pretreated with a solution (so-called sumping) for several hours before the dispersion treatment is performed in order to actually produce the printing ink.

【0004】

[Problems to be Solved by the Invention]

However, this pretreatment is time consuming and therefore costly. Even if "samping" and stirring are performed, the desired uniform dispersion is not always obtained, and as a result, printing may not be sufficiently satisfactory.

【0005】

Therefore, an object of the present invention is to provide a pearl light pigment which can considerably simplify and simplify the actual production of a printing ink and can achieve a particularly desired print quality, that is, an excellent pearl light effect.

【0006】

[Means for solving problems]

In the present invention, in a method for producing a pearl light pigment preparation as a pre-product of a printing ink containing a pearl light pigment, the pearl light pigment is made into a paste together with a binder and optionally a solvent and / or an additive. (However, all of these components are suitable for printing inks.) Then, the paste is made into a compressed grain shape and then the solvent is removed in that form, or the paste is first removed of the solvent and then made into a compressed grain shape. The present invention relates to a method for producing a pearl photopigment preparation, which is characterized by the above.

【0007】

In this case, the binder used may be a cellulose compound selected from the group consisting of cellulose nitrate, alkyl cellulose, hydroxy cellulose, hydroxyalkyl cellulose, and cellulose acetobutyrate.

【0008】

Further, the paste may be in a coarse grain shape.

【0009】

Further, the paste molding operation may be performed by tableting, pelletizing, granulating, spray granulating or extruding.

【0010】

Further, the paste molding operation may be performed by dropping or by mold molding.

【0011】

Further, 0.5 to 45% by weight, preferably 2 to 15% by weight, of a binder may be used with respect to the pearl photopigment.

【0012】

Further, the solvent removal performed before or after compression may be performed by drying under reduced pressure and / or temperature rise.

【0013】

The drying operation may at least partially sinter the particles.

【0014】

Also, the pearl photopigment used is based on mica, preferably muscovite, and is TiO.₂And / or Fe₂O₃A standard pigment may be coated with B, Al, Cr, Si, Sn, Zn, Zr or Ce-based metal oxide layer as an option.

【0015】

Further, the pearl photopigment used may be a standard pigment based on mica, preferably muscovite, and coated with titanium suboxide and / or titanium oxynitride and / or titanium nitride.

【0016】

Further, the pearl light pigment used may be a standard pigment based on mica, preferably muscovite, coated with a metal oxide, and further coated with a coloring pigment or a dye.

【0017】

Further, it may be a mixture of a pearl light pigment having a pearl light pigment component of 80 to 99.5% by weight and a metal effect pigment having a pearl light pigment component of 0.5 to 20% by weight based on Al, Cu, Zn, Sn and their alloys. ..

【0018】

Further, the pearl photopigment preparation may also contain a coloring pigment or dye in the range of 0.1 to 30% by weight based on the pearl light pigment.

【0019】

The present invention also relates to a pearl photopigment preparation in the form of a fluidable solvent-removed granule and a binder.

【0020】

In this case, the granule particle size may be 0.2 to 80 mm.

【0021】

Further, the present invention relates to a method of using the pearl photopigment preparation according to claim 14 or 15 as a printing ink, particularly an intaglio printing ink.

【0022】

BEST MODE FOR CARRYING OUT THE INVENTION

In the present invention, in a method for producing a pearl light pigment preparation as a pre-product of a printing ink containing a pearl light pigment, the pearl light pigment is made into a paste together with a binder and optionally a solvent and / or an additive. (However, all of these components are suitable for printing inks.) Then, the paste is made into a compressed grain shape and then the solvent is removed in that form, or the paste is first removed from the solvent and then made into a compressed grain shape. Thereby, a pearl photopigment can be produced, and a granular pre-product of a printing ink is provided.

【0023】

Surprisingly, if the pearl photopigment particles are prewetting with the necessary or desirable binder for the printing ink to be produced, the pigment particles will be printed very quickly and uniformly in the actual printing. We have found that it disperses in the binder used in ink production. From the user's point of view, this saves time, increases adaptability in connection with it, and significantly improves the pearl light effect in terms of printing. Surprisingly, given that the pearl photopigment formulation is present in the form of coarse particles, it is expected that a stronger mixing operation will be required to achieve uniform dispersion. Important in this regard, it seems surprising that the pre-wetting of the pigment particles with the corresponding binder remains even when the paste is transformed into a compact grain shape. Obviously, pressing or compressing the paste also results in a particularly dense prewetting of the pigment particles and the binder.

【0024】

The binder that can be used to pre-wet the pearl photopigment is any binder or mixture of binders normally used in printing inks, which is the same as or at least the binder used in the production of printing inks in the subsequent process. It suffices if they are equivalent. For example, cellulose, polyacrylate polymethacrylate, alkyd, polyester, polyphenol, urea, melamine, polyterpene, polyvinyl, polyvinyl chloride and polyvinylpyrrolidone resins, polystyrene, polyolefins, kumaron inden, hydrocarbons, ketones, aldehydes and aromatic formaldehyde resins, Binders based on hydrocarbons, polystyrenes, and epoxies, polyurethanes and / or natural oils or derivatives of these substances can be used. In the pearl photopigment preparation according to the present invention, particularly good redispersibility was obtained when cellulose or a cellulose compound was used as a binder. Obviously, cellulose or cellulose compounds cause dense pre-wetting of pearl photopigment particles, thus making it possible to make pre-printing ink products that can be rapidly dispersed in comparable binder solutions in printing ink production. This is especially true for cellulose compounds, which clearly promote the binding effect of pearl photopigment particles on the one hand and the formation of the paste from which the formulation is produced in the form of compressed particles on the other hand.

【0025】

A group of cellulose or cellulose compounds particularly suitable for the method according to the invention includes cellulose nitrate, alkyl cellulose, hydroxy cellulose, hydroxyalkyl cellulose, and cellulose acetobutyrate.

【0026】

The amount of binder used is not important, but is in the range of 0.5 to 45% by weight, preferably 2 to 15% by weight.

【0027】

What is important is the viscosity of the mixture, which can be adjusted by adding a solvent to the binder prior to molding into a compressed grain shape. This is because if the solvent concentration in the mixture is too high, the pearl photopigment tends to separate from the binder solution, and if the viscosity is too high, the wetting effect becomes incomplete and the granulation work becomes considerably difficult. Because.

【0028】

The conversion of the pearl photopigment paste to the compressed grain form can be carried out by using various methods well known to those skilled in the art, such as tableting, pelleting, granulation, spray granulation or extrusion. In any of these cases, pressure is applied to the paste, which is in a more or less viscous state, and the pressure promotes pre-wetting of the pigment particles and the binder. Thus, the particles are tablets, briquettes, pellets, granules, balls, small sausages, and other corresponding coarse particles. Pressing or extrusion is particularly preferred as the compression method used.

【0029】

Small sausage-like particles are obtained by pressing the mixture of the pearl photopigment paste and the binder solution in a batch with a piston or continuously with an extruder using a plate with small holes. .. By appropriately adjusting the viscosity of the mixture, the particle length that is cut or cut from the perforated plate is automatically adjusted. Particle formation by dividing an elongated object coming out of a perforated plate can also be performed by a known mechanical method, for example, by rotating a cutting blade. Pelletization or granulation can be performed by a known method using a pellet plate or a granulation container, and the preparation becomes spherical. The particles formed by pressing with a perforated plate can be further post-molded into pellets or granules. Tableting and briquetting can be performed by appropriately pressing the paste with a mold.

【0030】

By essentially removing the solvent contained in the binder during the drying process after molding the formulation particles, the formulation particles, on the one hand, exhibit sufficient mechanical strength to retain their shape during handling and transportation, and on the other hand, they are bound. When it comes into contact with the coating solution, it breaks rapidly and disperses even with a small amount of mechanical action (stirring).

【0031】

If the binder has sufficient viscosity to compress the paste in the form of particles even after removing the solvent, it is possible to remove the solvent from the paste by drying before the compression operation. .. Optionally, the viscosity can be reduced by increasing the paste temperature for compression work.

【0032】

The nature of the drying operation of the paste or the drying operation of the particles produced by the compression and the effect of the solvent removal carried out by it essentially depend on the nature of the solvent used. Most of the solvents mentioned in the present specification are volatile below the softening point of the binder, especially when the binder is cellulose, so that the drying operation can be performed at a high temperature. In that regard, in the drying operation, selecting a temperature near the binder softening point can cause sintering to at least the edge layers of the pearl photopigment particles coated or pre-wetted with the binder. This improves the shape stability of the formulation particles during handling and during transfer.

【0033】

The present invention is based on mica such as muscovite, biotite or synthetic mica, and is TiO.₂And / or Fe₂O₃It is also related to the pearl photopigment coated with. As an option, an additional B, Al, Cr, Si, Sn, Zn, Zr or Ce-based metal oxide layer can be additionally included. Similarly, it is also possible to use a pearl photopigment coated with titanium suboxide, titanium oxynitride, titanium nitride or a mixture thereof.

【0034】

In addition to coating the metal oxide, the pearl light pigment can also be coated with a coloring pigment or dye. It is also possible to achieve coloring by mixing a coloring substance with a pearl light pigment in a paste forming operation.

【0035】

According to the method according to the present invention, it is also possible to produce a mixture of a pearl light pigment and a metal pigment in a desired ratio. This is because it has been found that some metal pigments do not adversely affect the pre-wetting with the binder. However, the proportion of metal pigments should not exceed 20% by weight relative to pearl light pigments. Suitable metal pigments are any metal currently used in the field of effect pigments, such as aluminum, copper, zinc, tin and alloys thereof, with aluminum and gold bronze pigments being particularly preferred.

【0036】

[Effect of the invention]

As described above, according to the present invention, the actual production of the printing ink can be considerably simplified and simplified, and a particularly desired print quality, that is, an excellent pearl light effect can be achieved. obtain.