RU2443737C2 - Titanium dioxide based pigment, methods of producing titanium dioxide based pigment and pigment obtained using one of said methods, decorative paper, method of making decorative paper, method of making decorative coating materials and decorative coating materials - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: titanium dioxide based pigment, containing titanium dioxide particles, has a coating layer containing aluminium phosphate and aluminium oxide, and said layer additionally contains hollow particles. To obtain said pigment, aqueous suspension of titanium dioxide is prepared first, and aluminium- and phosphorus-containing components are then added, after which hollow particles are added and pH of the suspension is brought to 4-9. Also, aqueous suspension of titanium dioxide can be obtained at pH not lower than 10, and aluminium- and phosphorus-containing components can then be added while maintaining pH of at least 10, after which hollow particles are added. Further, pH of the suspension is brought to 4-9 and an aluminium oxide coating is then applied at pH from 4 to 9.

EFFECT: invention increases opaqueness and retention of pigment when making decorative paper.

22 cl, 1 dwg, 1 tbl, 1 ex

Description

FIELD OF THE INVENTION

The invention relates to a pigment based on titanium dioxide with good opacity and to a method for its preparation and use in the manufacture of decorative paper and decorative foil.

State of the art

Decorative paper or decorative foil is the main part of decorative thermosetting coating materials, which are mainly used for decoration of furniture surfaces, for laminated floors and for interior decoration. Laminate is a laminated product pressed from several materials, for example, compressed multilayer impregnated paper, or paper and hard fiber, or chipboard. Thanks to the use of special synthetic resins, extremely high heat resistance, resistance to scratches, impact, and chemicals are achieved.

The use of decorative paper (all of the following should also be applied to decorative foil) makes it possible to obtain a decorated surface, while decorative paper serves not only as a coating, for example, of an unattractive chipboard, but also as a carrier for synthetic resin.

The requirements for decorative paper include, among others, opacity (hiding power), light fastness (resistance to darkening), color fastness, moisture resistance, impregnation ability and printing properties.

The validity of the new method for producing decorative paper is determined, first of all, by the degree of opacity of the pigment in the paper. To achieve the necessary degree of opacity of decorative paper, a pigment based on titanium dioxide is a fundamentally suitable basis. In papermaking, titanium dioxide-based pigment or a suspension containing titanium dioxide-based pigment is typically mixed with a suspension of cellulose. In addition to the introduced pigment and cellulose materials, as a rule, it is necessary to add auxiliary substances, for example, substances that impart moisture resistance, in some cases it is necessary to introduce other additional substances as fillers. The interaction of individual components (such as cellulose, pigment, auxiliary and additional substances, water) among themselves favors the production of paper and is determined by a parameter such as retention of the pigment. By retention is meant the ability of all inorganic compounds in paper to remain in a homogeneous state upon receipt. An important role is played by the surface charge of the pigment in relation to the cellulose fiber.

It is known that one of the ways to achieve improved opacity is a special modification of the surface of the particles of titanium dioxide pigment.

US Pat. Nos. 5,942,281 and US 5,665,466 describe a method for modifying the surface of pigment particles. According to this method, in the first stage, the particles are coated with aluminum oxyphosphate at a pH of from 4 to 6. Then, in the next stage, a second layer of aluminum oxide is deposited on the pigment particle at a pH of from 3 to 10, preferably at a pH of about 7. Improvement retention value is achieved by applying a third layer consisting of magnesium oxide. Thus, a characteristic feature of the obtained pigment is that its particles contain three coating layers, following each other: aluminum oxyphosphate, aluminum oxide and magnesium oxide.

US Pat. No. 6,962,622 describes a pigment based on titanium dioxide as a mixture. It consists of a pigment with high resistance to darkening (A-type pigment) and a pigment with a modified surface coating, which has a high content of silicon oxide and alumina (B-type pigment).

US Pat. No. 6,143,064 describes the deposition of calcium carbonate onto pigment particles, wherein the calcium carbonate particles have a size of 30 to 100 nm. Paper made using titanium dioxide coated with a layer of calcium carbonate has a high degree of opacity. The particles of calcium carbonate provide a certain gap between the pigment particles, which leads to an improved distribution of pigment particles in the paper. The minimum distance between the pigment particles should correspond to the size of the pigment particles. US patents Nos. 5886069 and 5650002 describe a pigment containing TiO ₂ , the particles of which have both a solid inorganic coating and a coating of individual inorganic particles with a diameter of 5-100 nm. Particles can be of any shape, with coatings applied in any order. The pigment is obtained by mixing a colloidal suspension of individual particles with a suspension of TiO ₂ .

U.S. Application No. 2003/0024437 A1 describes a pigment in the form of a mixture of particles of various pigments onto which surface spherical particles of calcium carbonate, silica, alumina, zirconia and titanium oxide are deposited on the surface.

Disclosure of invention

The objective of this invention is to create alternative titanium dioxide pigments with good opacity and retention to create decorative paper. Another objective of the invention is the expansion and development of methods for producing such titanium dioxide pigments.

The solution to the first problem is that the titanium dioxide pigment contains titanium dioxide particles, on the surface of which there is a layer comprising aluminum phosphate, aluminum oxide and hollow particles.

A further solution to the problem consists in a method for producing a titanium dioxide pigment with a modified coating, according to the following stages:

a) obtaining an aqueous suspension of still uncovered particles of titanium dioxide;

b) the addition of aluminum and phosphorus-containing components;

c) the addition of hollow particles;

g) adjusting the pH of the suspension to 4 ÷ 9.

Further embodiments of the invention are described below.

Brief Description of the Drawings

1 is a photograph of a titanium dioxide-based pigment particle having a layer including aluminum phosphate, alumina and hollow particles.

The implementation of the invention

Hereinafter, the word "oxide" will mean an oxide containing water, that is, respectively, a hydrate. All subsequent data on pH, temperature, concentration in mass% and volume% cover all values that lie in the field of the corresponding measurement accuracy known to specialists. The indication "significant amount" or "significant part" within the framework of this patent refers to the minimum amount of a component above which, within the framework of a given measurement accuracy, a change in the properties of the mixture occurs.

A distinctive feature of the pigment obtained according to the present invention is the use of hollow particles. Hollow particles are understood as hollow bodies of various shapes: microspheres and other particles. Hollow particles are used, according to the invention, in the final stage of processing. Hollow particles are deposited on the surface of the pigment particles, and serve as a kind of interlayers between the pigment particles. Hollow particles can be made from both organic substances and inorganic substances. Their diameter averages 5–1000 nm. Hollow particles are characterized by the fact that they include air inclusions, and these inclusions appear in this case only after drying. Organic hollow particles are typically used as a filler in paints. Hollow particles serve as interlayers between pigment particles. It should be emphasized that hollow particles contain air inclusions. A specific refractive index between the pigment and the air increases the opacity (see "Improving the Quality of Ropaque ^™ Opaque ^™ Polymer to Improve Varnishes and Paints", Phanomen Farbe 2/98, 1/99). To obtain hollow organic particles, they are guided by the publication "Hollow latex particles: synthesis and applications" (McDonald et al., Advances in Colloid and Interface Science, 2002, 99: 181-213). The preparation of hollow inorganic particles is described in "Nanoengineering of Inorganic and Hybrid Hollow Spheres by Colloidal Templating" (Caruso etal., Science, 1998, 282: 1111). International publication WO 02/074431 A1 discloses a method for producing hollow inorganic particles and their use in catalysis and fiber optics.

According to the method proposed in this invention, a layer containing aluminum and phosphorus compounds mixed with hollow particles and aluminum oxide is deposited on the surface of TiO ₂ particles. The composition of this mixture depends on the loaded amount of aluminum and phosphorus-containing components. In the future, this layer is simplistically considered as hollow particles of aluminum oxyphosphate. Subsequent treatment, based on the present invention, is based on aqueous, preferably wet, grinding of a suspension of TiO ₂ (step a). Wet grinding is carried out in this case in the presence of a dispersant.

Titanium dioxide TiO ₂ is understood to mean uncoated particles of TiO ₂ , that is, the main substance TiO ₂ obtained either by the sulfate (SP) or chloride (CP) method. This basic substance is generally stabilized. In the CP method, for stabilization, an aluminum-containing component is added in an amount of from 0.3 to 3 wt.% In terms of Al ₂ O ₃ and titanium tetrachloride is oxidized to titanium dioxide with excess oxygen (2-15%) in the gas phase. In the SP process, stabilization is carried out by adding a small amount of Al, Sb, Nb or Zn. In the preparation of TiO ₂ particles, a chloride process is preferably used.

The process is carried out at a temperature below 80 ° C, preferably at 55 ÷ 65 ° C. The suspension in step a) can have either an alkaline or acidic reaction with a pH of preferably> 9 or <4. In step b), aluminum and phosphorus-containing components are added.

Suitable aluminum-containing components for the surface modification method of the present invention are the corresponding water-soluble alkali or acid salts, for example sodium aluminate, aluminum sulfate, aluminum nitrate, aluminum chloride, aluminum acetate, etc. It should not be considered that the above list is limited to the listed substances. The aluminum-containing component should be added in an amount of from 1.0 to 5.0 wt.%, Preferably from 1.5 to 4.5 wt.% And particularly preferably 2.0 wt.% In terms of Al ₂ O ₃ (relative to TiO ₂ particles).

Suitable phosphorus-containing components are inorganic compounds such as alkali metal phosphates, ammonium phosphate, polyphosphates, phosphoric acid, etc. It should not be considered that the above list is limited to the listed substances. Most suitable is sodium phosphate monoxide (Na ₂ HPO ₄ ) or phosphoric acid. The phosphorus-containing component is added in a concentration of from 1.0 to 5.0 wt.%, Preferably from 1.5 to 4.0 wt.%, Particularly preferably from 2.0 to 3.0 wt.% In terms of P ₂ O ₅ (relative to TiO ₂ particles). Aluminum and phosphorus-containing components can be added to the suspension in any sequence - simultaneously or in turn. In the next step c), organic or inorganic hollow particles with an average diameter of from 5 to 1000 nm, preferably from 400 to 600 nm, are added.

Suitable organic hollow particles are, for example, the Ropaque ^™ product from Rohm & Haas. The product Ropaque ^TM should be understood as hollow particles of a styrene-acrylic copolymer in the form of spheres. Hollow spheres made of latex or other polymers are also suitable. It should not be considered that the above list is limited to the listed substances. Essentially essentially any hollow organic particles having a desired diameter in the range of 5 to 1000 nm and which are stable at appropriate pH values. Inorganic hollow particles are currently considered glass hollow particles and ceramic hollow balls, as well as hollow balls made of TiO ₂ . It is also important that any kind of hollow inorganic particles are applicable according to the present invention if they have the required average diameter of 5 to 1000 nm, since they are stable at the pH values used. Based on predetermined factors, such as technological properties, price, etc., specialists can select suitable hollow particles. Hollow particles are added in an amount of from 1 to 15 wt.% Relative to the mass of uncoated particles of TiO ₂ . In a subsequent step d) the pH of the suspension is adjusted to 4 to 9 by the addition of a pH adjusting component. The pH adjusting component used may be acidic or alkaline. As the acids, for example, sulfuric, hydrochloric, phosphoric or any other suitable acid may be used. In addition, it is possible to use, instead of acids, the corresponding salts having an acid reaction, for example aluminum sulfate. You can also use acidic solutions of metal salts: cerium, titanium, zirconium, so that there is a joint deposition of a layer of Ti, Ce, Zr compounds, hollow beads and aluminum oxyphosphate on the surface of the pigment particles. Sodium hydroxide is preferably used as alkali. Alkaline salts are also suitable. Suitable pH adjusting compounds are known to those skilled in the art. It should not be assumed that in the above examples all possible substances are listed.

It turned out to be beneficial, at the next stage e) to apply a layer of aluminum oxide on a layer of hollow balls and aluminum oxyphosphate; This can be done in several ways. Firstly, by the parallel addition of alkaline and acidic aluminum-containing components (for example, sodium aluminate and aluminum sulfate). Secondly, by adding an alkaline aluminum-containing component, such as sodium aluminate, and an acid, such as sulfuric or hydrochloric. Secondly, by adding an acidic aluminum-containing component, such as, for example, aluminum sulfate together with an alkali, for example NaOH. In all three cases, the pH is maintained in the range from 4 to 9. In addition, the components can be added in two ways: 1) so that the pH remains constant in the range from 4 to 9 or 2) the components are added so that the pH in the course of addition ranged from 4 to 9. Those skilled in the art will know the appropriate sequence of actions. In order to adjust the pH, in particular alkalis and acids (for example, NaOH and H ₂ SO ₄ ) or solutions of salts with alkaline or acidic properties (for example, sodium aluminate and aluminum sulfate) are suitable. As it turned out, the treatment carried out at a pH established in step d) is particularly favorable.

If necessary, at stage e) the pH is adjusted in the range from 5 to 8, for example, using alkalis (NaOH, etc.) or acids (H ₂ SO ₄ , HCl, etc.). In addition, at this stage, for adjusting the pH, aqueous solutions of salts having acidic or alkaline properties are suitable, for example a solution of sodium aluminate or aluminum sulfate.

The amount of aluminum-containing compounds introduced in stages d), e) and e) is converted to Al ₂ O ₃ and taken into account already in stage b). The total aluminum-containing component in terms of Al ₂ O ₃ introduced into the suspension in stages b) to e) relative to the mass of uncoated particles of TiO ₂ should be from 1.0 to 9.0 wt.%, Preferably from 3.5 to 7, 5 wt.% And particularly preferably 5.5 wt.%. Also, the amount of the phosphorus-containing component introduced in steps d) and e) is converted to P ₂ O ₅ and taken into account in step b). The total phosphorus-containing component in terms of P ₂ O ₅ introduced into the suspension in stages b) to e) should be from 1.0 to 5.0 wt.%, Relative to the mass of uncoated particles of TiO ₂ , more preferably from 1.5 up to 3.5 wt.% and particularly preferably from 2.0 to 3.0 wt.%.

Also, some metal salts, for example, cerium, titanium, zirconium, zinc, as well as silicon compounds, which are then precipitated together with a layer of hollow balls and aluminum oxyphosphate in the form of the corresponding phosphates or oxides, can be added to the suspension together with aluminum and phosphorus-containing components.

Further, it is possible to apply the following inorganic layer to the pigment particles. This can be done both before stage d) and after stage d), using well-known technologies (for example, a layer of zinc-, titanium- and silicon-containing compounds can be applied).

According to the invention, in the proposed method, it is preferable to use an alkaline suspension of TiO ₂ . For this, in step a), a suitable alkaline component, for example NaOH, is added to the suspension in order to set the pH to at least 10. This is desirable if wet grinding is carried out, which is the best method of homogenization.

At stage b), aluminum and phosphorus-containing components in the form of aqueous solutions are successively added to the suspension. When adding the components, it is preferable to maintain the pH of the suspension at least 10, preferably 10.5, and particularly preferably 11.

Sodium aluminate is particularly suitable as an alkaline aluminum-containing component. By adding acidic components, such as, for example, aluminum sulfate, the pH drops below 10; to eliminate this effect, compounds with alkaline properties, for example sodium hydroxide, are added. Suitable compounds having alkaline properties are known to those skilled in the art, and the required amount is necessary to maintain a pH of at least 10.

In the case of adding phosphorus-containing components, it is also possible to lower the pH below 10, in order to eliminate this effect, add compounds with alkaline properties, for example sodium hydroxide. Suitable compounds having alkaline properties and the necessary amount thereof are known to those skilled in the art to maintain a pH below 10.

Aluminum and phosphorus-containing components can be added to the suspension in any order. In the next step c) organic or inorganic hollow particles with an average diameter of from 5 to 1000 nm, preferably from 400 to 600 nm are added, while the pH of the suspension should not fall below 10, preferably not lower than 10.5, particularly preferably not lower than 11 .

In the next step d), a pH adjusting component is added so that the pH is in the range of 4 to 9.

According to an alternative method of the present invention, the modification of the surface of the pigment can be carried out at acidic pH values.

According to this method, in step b) aluminum and phosphorus-containing components are added so that the pH of the suspension becomes less than 4. The person skilled in the art can choose to acidify the suspension in step a) using a suitable acid or in step b) using a combination of aluminum and phosphorus-containing components; in any case, the pH should be less than 4. Examples of suitable combinations of aluminum and phosphorus-containing components may include the following combinations: phosphoric acid and sodium aluminate or disodium hydroorthophosphate and aluminum sulfate. The components may be added to the suspension in any order.

In step c), only hollow particles are used which are stable at acidic pH values.

In step d), the pH adjusting component is again added so as to maintain the pH from 4 to 9.

The surface-modified TiO ₂ pigment is isolated from the suspension using known laboratory techniques; after filtration, the raw pigment is washed to remove water-soluble salts. In order to improve the light fastness of the pigments in the laminate, inorganic nitrates, for example, KNO ₃ , NaNO ₃ , Al (NO ₃ ) ₃ in an amount of 0.05 to 0.5 wt.% In terms of NO ₃ , are added to the pigment freshly washed on the filter paste. what to produce drying. During the final grinding, for example, using a ball mill, an organic compound can be added to the pigment from a number of substances commonly used in the preparation of the TiO ₂ pigment and which are well known in the art, such as polyalcohols (trimethylolpropane). An alternative to the addition of nitrate-containing compounds before or during the drying process may be the addition of these compounds during grinding.

The pigment obtained by this method exhibits high opacity with respect to the reference sample and is best suited for the manufacture of decorative paper. Decorative paper can be used to make decorative coating materials.

The method for modifying the surface of the pigment particles claimed in this invention is usually carried out as a batch process. It is also possible to carry out the modification process continuously, with the help of suitable mixing devices known to those skilled in the art. This mixing device must be guaranteed to carry out the necessary mixing.

Examples of carrying out the invention

The following are examples of the invention, contributing to a better understanding.

Example (according to the invention)

NaOH to pH = 10 is added to a suspension of TiO ₂ -rutyl obtained by the chloride method with a TiO ₂ concentration _of 350 g / L at 60 ° C and ground to a sand state. With stirring, sodium aluminate was added in an amount of 2.0 wt.% In terms of Al ₂ O ₃ . After 15 minutes of stirring, disodium hydrogen phosphate was added as a solution up to 2.4 wt.%, Calculated as P ₂ O ₅ . It was kept under stirring for another 15 minutes. In the next step, a 30% Ropque Ultra emulsion (polymer hollow microspheres from Rohm & Haas) is added to the suspension so that the content of the active component in the form of a styrene-acrylic copolymer relative to titanium dioxide is 2 wt.%. After this was mixed for another 15 minutes In the next step, an aluminum sulfate solution is added to the suspension, so that the amount of aluminum in terms of Al ₂ O ₃ is 2.6%, and the pH becomes approximately equal to 5. Then, aluminum-containing components are added to the resulting suspension in an amount of 0.7 mass .% in terms of Al ₂ O ₃ ; for this, simultaneous addition of solutions of sodium aluminate and aluminum sulfate is carried out, so that pH = 5.

After 30 minutes of stirring, the pH of the suspension was adjusted to about 5.8 by the addition of an alkaline solution of sodium aluminate. Then filter and wash the solid residue on the filter to remove water-soluble salts. 0.25 wt.% NaNO ₃ in terms of NO _{3 is} added to the pigment paste freshly washed on the filter, after which the dry pigment is dried and crushed in a ball mill.

Studies using a transmission electron microscope showed that hollow microspheres are contained on the surface of the pigment particles.

Comparative experiment

NaOH to pH = 10 is added to a suspension of TiO ₂ -rutyl obtained by the chloride method with a TiO ₂ concentration _of 350 g / L at 60 ° C and ground to a sand state. With stirring, sodium aluminate is added, to a content of 2.0 wt.% In terms of Al ₂ O ₃ . Stirred for 15 minutes and add disodium hydrogen phosphate in the form of a solution up to 2.4 wt.%, In terms of P ₂ O ₅ . Mix for another 15 minutes. In the next step, a solution of aluminum sulfate is added to the suspension until the aluminum content in terms of Al ₂ O _{3 is} 2.6 wt.%, The pH becomes approximately equal to 5. Then, aluminum-containing components are added to the resulting suspension in an amount of 0.8 wt. % in terms of Al ₂ O ₃ ; for this, solutions of sodium aluminate and aluminum sulfate are simultaneously added, so that pH = 5.

Stirred for 30 minutes, then the pH of the suspension was adjusted to about 5.8 by the addition of an alkaline solution of sodium aluminate. Then filter and wash the solid residue on the filter to remove water-soluble salts. 0.25 wt.% NaNO ₃ in terms of NO _{3 is} added to the pigment paste freshly washed on the filter, then dry pigment is dried and ground in a ball mill.

Test method.

To evaluate the optical properties of decorative paper and the quality of a pigment based on titanium dioxide, it is necessary to compare the ash content of decorative paper samples. For this purpose, sheets of decorative paper are made with a sheet density of 80 g / m ² and an ash content of 30 g / m ² . The sequence of actions and the auxiliary materials used are known to those skilled in the art.

The content of titanium dioxide (ash) in the sheets of paper, as well as the retention of the pigment is determined by the following methods.

a) Ash

To determine the content of titanium dioxide in the manufactured paper, a certain sample of the test paper is taken and converted into ash using a device for determining the ash content of paper with rapid heating to 900 ° C. Mass loss determines the mass fraction of TiO ₂ (ash) in wt.%. To calculate the ash content, the following formula is used:

Ash content [g / m ² ] = (ash [mass% -%] * weight per unit area [g / m ² ]) / 100 [%]

b) Retention

By retention is meant the ability of all inorganic substances to be retained in a sheet of paper on a grid of a paper machine. The so-called one-pass retention, which is defined here, is characterized by a part (in percent) of inorganic substances held during a single loading of the paper machine. The percentage of ash relative to the mass of pigment used in the total solid phase of the suspension characterizes the retention:

c) Optical properties

The optical properties of the pigments are determined in the laminate.

To do this, the decorative paper is impregnated, using a modified melamine glue, pressed into the laminate. The resin-coated sheets are completely dipped in melamine glue, then twice drawn through the squeegee to guarantee the application of a certain layer of resin and, immediately after that, they are placed for preliminary drying in a chamber dryer with circulating air at 130 ° C. The applied resin layer makes up from 120 to 140% of the mass of the sheets. The sheets had a residual moisture content of about 6 wt.%. The dried compacted sheets are pressed together with a paper base impregnated with phenolic resin, and with a white or black paper substrate. To evaluate the test pigment, an 11-layer laminate is made: decorative paper, white-black backing, paper backing, paper backing, paper backing, white backing, paper backing, paper backing, paper backing, white-black backing, decorative paper. The laminate preform was pressed on a Wickert Laminat-Presse Tur 2742 press at a temperature of 140 ° C and a pressure of 900 N / cm ² , with a pressing time of 300 seconds.

The optical properties of the laminate were measured with a standard spectrophotometer.

To evaluate the optical properties of the laminates, the color components of decorative paper (CIELAB L ^* , -a ^* , -b ^* ) were determined according to DIN 6174 using an ELREPHO ^® 3000 colorimeter, on a white and black substrate.

Opacity is a characteristic of the transparency or light transmission of paper. The following are selected as opacity values: CIELAB L ^* _black , reflectivity of the laminate measured for a black paper substrate, opacity L [%] = (Y _black / Y _white ) × 100, determined from the Y value of the decorative paper measured for black paper substrate (Y _black ), and the Y value measured for a white paper substrate (Y _white ).

results

Table 1 shows the test results for the laminate. These results were obtained for a pigment prepared according to the method of the present invention (example) and according to the method described in the comparative experiment. The pigment obtained according to the method proposed in this invention exhibits improved opacity characteristics relative to the pigment obtained in the comparative experiment.

Table 1 Pigment Opacity Retention L ^* _black L [%] [%] Example 90.3 91.1 69 Example (comparative) 90.1 90.7 71

Claims (22)

1. A titanium dioxide-based pigment comprising titanium dioxide particles having a coating layer comprising aluminum phosphate and alumina, characterized in that the layer further comprises hollow particles. 2. The pigment according to claim 1, characterized in that the hollow particles are characterized by an average diameter of from 5 to 1000 nm. 3. The pigment according to claim 1, characterized in that the layer comprises an aluminum-containing component when contained in terms of aluminum oxide (Al ₂ O ₃ ), wt.%: 1.0 ÷ 9.0. 4. The pigment according to claim 1, characterized in that the layer includes a phosphorus-containing component when contained in terms of P ₂ O ₅ , wt.%: 1.0 ÷ 5.0. 5. A method for producing a pigment based on titanium dioxide, the particles of which are coated with a layer, characterized in that first an aqueous suspension of the starting titanium dioxide is obtained, then aluminum-containing and phosphorus-containing components are added, then hollow particles are added and, finally, the pH of the suspension is adjusted to 4 ÷ 9 . 6. The method according to claim 5, characterized in that when receiving an aqueous suspension of the initial titanium dioxide and adding aluminum-containing and phosphorus-containing components maintain a pH of at least 10. 7. The method according to claim 5, characterized in that when the aluminum-containing and phosphorus-containing components are added, the pH of the suspension is kept below 4. 8. The method according to claim 5, characterized in that it uses hollow particles, characterized by an average diameter of from 5 to 1000 nm. 9. The method according to claim 5, characterized in that it further includes applying a layer of alumina at a pH of from 4 to 9. 10. The method according to claim 5, characterized in that the aluminum-containing components are added to the content in terms of aluminum oxide (Al ₂ O ₃ ), wt.%: 1.0-9.0. 11. The method according to claim 5, characterized in that the phosphorus-containing components are added to the content in terms of P ₂ O ₅ , wt.%: 1.0 ÷ 5.0. 12. The method according to claim 5, characterized in that, simultaneously with the addition of aluminum-containing and phosphorus-containing components to the suspension, solutions of salts such as Ce, Ti, Si, Zr or Zn salts are additionally added. 13. The method according to claim 9, characterized in that it further includes bringing the pH of the suspension to 5 ÷ 8. 14. The method according to claim 5, characterized in that in it, when adjusting the pH to 4 ÷ 9, acidic solutions of metal salts, such as Ce, Ti or Zr salts, are used. 15. The method according to claim 5, characterized in that it further includes processing the pigment particles with nitrates to a nitrate content in the finished pigment from 0.05 to 0.5 wt.%. 16. The method according to claim 5, characterized in that it further includes grinding the pigment particles with the addition of organic substances. 17. A method of producing a titanium dioxide-based pigment, the particles of which are coated with a layer, characterized in that an aqueous suspension of the starting titanium dioxide is first obtained at a pH of at least 10, then aluminum-containing and phosphorus-containing components are added while maintaining a pH of at least 10, then added components containing hollow particles, after which the pH of the suspension is adjusted to 4–9 and, finally, an aluminum oxide coating is applied at a pH of 4 to 9. 18. A pigment based on titanium dioxide, characterized in that it is the obtained method according to claim 5. 19. The use of a titanium dioxide-based pigment according to any one of claims 1 or 18 as a means in the manufacture of decorative paper. 20. Decorative paper, characterized in that it includes a pigment based on titanium dioxide according to claim 1 or 18. 21. The use of decorative paper, including a titanium dioxide-based pigment according to claim 1 or 18, as a means in the manufacture of decorative coating materials. 22. Decorative coating materials, characterized in that they contain decorative paper according to claim 20.

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