Classifications

• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
  • C09C3/00—Treatment in general of inorganic materials, other than fibrous fillers, to enhance their pigmenting or filling properties
  • C09C3/06—Treatment with inorganic compounds
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
  • C09C1/00—Treatment of specific inorganic materials other than fibrous fillers; Preparation of carbon black
  • C09C1/36—Compounds of titanium
  • C09C1/3607—Titanium dioxide
  • C09C1/3653—Treatment with inorganic compounds
  • C09C1/3661—Coating
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
  • C09C1/00—Treatment of specific inorganic materials other than fibrous fillers; Preparation of carbon black
  • C09C1/36—Compounds of titanium
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
  • C09C1/00—Treatment of specific inorganic materials other than fibrous fillers; Preparation of carbon black
  • C09C1/36—Compounds of titanium
  • C09C1/3607—Titanium dioxide
  • C09C1/3653—Treatment with inorganic compounds
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H27/00—Special paper not otherwise provided for, e.g. made by multi-step processes
  • D21H27/18—Paper- or board-based structures for surface covering
  • D21H27/22—Structures being applied on the surface by special manufacturing processes, e.g. in presses
  • D21H27/26—Structures being applied on the surface by special manufacturing processes, e.g. in presses characterised by the overlay sheet or the top layers of the structures
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
  • C01P2004/00—Particle morphology
  • C01P2004/80—Particles consisting of a mixture of two or more inorganic phases
  • C01P2004/82—Particles consisting of a mixture of two or more inorganic phases two phases having the same anion, e.g. both oxidic phases
  • C01P2004/84—Particles consisting of a mixture of two or more inorganic phases two phases having the same anion, e.g. both oxidic phases one phase coated with the other
  • C01P2004/86—Thin layer coatings, i.e. the coating thickness being less than 0.1 time the particle radius
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
  • C01P2006/00—Physical properties of inorganic compounds
  • C01P2006/60—Optical properties, e.g. expressed in CIELAB-values
  • C01P2006/62—L* (lightness axis)
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
  • C01P2006/00—Physical properties of inorganic compounds
  • C01P2006/80—Compositional purity
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
  • D21H17/63—Inorganic compounds
  • D21H17/67—Water-insoluble compounds, e.g. fillers, pigments
  • D21H17/675—Oxides, hydroxides or carbonates
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
  • D21H17/63—Inorganic compounds
  • D21H17/67—Water-insoluble compounds, e.g. fillers, pigments
  • D21H17/69—Water-insoluble compounds, e.g. fillers, pigments modified, e.g. by association with other compositions prior to incorporation in the pulp or paper
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
  • D21H21/14—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties characterised by function or properties in or on the paper
  • D21H21/28—Colorants ; Pigments or opacifying agents
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
  • Y10T428/2982—Particulate matter [e.g., sphere, flake, etc.]
  • Y10T428/2991—Coated

Definitions

• the invention relates to a process for the surface treatment of a titanium dioxide pigment, a titanium dioxide pigment with high light fastness (graying stability) and its
• Decorative paper is a component of a decorative, thermosetting
• Laminates are laminates in which, for example, several impregnated, laminated papers or papers and hardboard or chipboard are pressed together. The use of special resins results in extremely high scratch, impact, chemical and heat resistance of the laminates.
• the requirements for a decorative paper include, but are not limited to: Opacity (hiding power), light fastness (graying stability), color fastness, wet strength, impregnability and printability.
• a pigment based on titanium dioxide is in principle outstandingly suitable.
• a titanium dioxide pigment or a titanium dioxide pigment suspension is usually mixed with a pulp suspension.
• feedstock pigment and pulp come in
• auxiliaries such.
• Additives such as, certain fillers are used.
• the interactions of the individual components (pulp, pigment, auxiliaries and additives, water) with each other contribute to paper formation and determine the retention of the pigment.
• Retention refers to the retention capacity of all inorganic substances in the paper in the Production.
• titanium dioxide pigments for use in decorative paper. Lightfastness is one of the most important properties in addition to good brightness and opacity. Titanium dioxide is known to be photochemically active. A decorative paper pigmented with titanium dioxide exhibits increasing graying under the action of UV radiation in the presence of moisture and oxygen. Lightfastness is understood above all as the resistance of the laminates to graying under the action of UV radiation. To improve the light fastness (graying stability) of decorative paper, the titanium dioxide pigment is usually mixed with aluminum compounds in particular
• US 5,114,486 discloses coating with zinc / aluminum phosphate to improve graying stability.
• US 5,785,748 describes a process for the uniform coating of titanium dioxide with aluminum phosphate, in which a mixture of concentrated phosphoric acid and an aluminum compound is added to a titanium dioxide suspension, and
• Aluminum phosphate is precipitated at a pH of 3.5 or more.
• WO 2004/061013 A2 discloses a titanium dioxide pigment with good graying stability for use in decor paper, which is provided with an aluminum phosphate coating and which has particularly favorable surface properties in terms of isoelectric point and zeta potential.
• the aluminum phosphate layer is precipitated at a constant pH of 7.
• the coated pigment is finally subjected to a heat treatment.
• a titanium dioxide pigment having high graying stability and at the same time improved retention and opacity can be produced.
• the method is characterized in that an aluminum and a phosphorus component are added at a constant pH of at least 10 in a titanium dioxide suspension and then the pH is lowered to below 9 to precipitate aluminum phosphate.
• the object of the invention is to provide a method by which titanium dioxide pigments can be produced with improved grayness stability with respect to the prior art while maintaining high brightness and opacity for use in decorative papers.
• the object is achieved by a process for producing a post-treated titanium dioxide pigment, which comprises the following steps:
• the invention thus relates to an aftertreatment process for titanium dioxide pigments, which leads to pigments having improved graying stability while maintaining high brightness and opacity, furthermore a pigment having these properties and the use of this pigment in decorative paper production.
• oxide should also be understood to mean the corresponding hydrous oxides or hydrates. All of the details disclosed below with regard to pH, temperature, concentration in% by weight or% by volume etc. are to be understood as follows in that all values which are within the range of the respective measuring accuracy known to those skilled in the art are included.
• significant amount or “significant proportion” in the context of the present patent denotes the minimum quantity of a component above which the properties of the mixture in the context of Measuring accuracy can be influenced.
• the invention is based on untreated titanium dioxide particles (titanium dioxide base body), which were prepared by the chloride process or by the sulfate process.
• the titanium dioxide particles are preferably aluminum-doped. Particularly suitable are aluminum-doped titanium dioxide particles produced by the chloride process.
• Aluminum doping is preferably 0.5 to 2.0 wt .-% calculated as Al 2 0 3rd
• a layer of aluminum-phosphorus compounds optionally in a mixture with
• Alumina hydrate deposited The composition is dependent on the amounts of the aluminum and phosphorus components used and the amount of doped Al 2 O 3 present if appropriate. Hereinafter, this layer will be referred to simply as alumina phosphate layer.
• the inventive method is based on an aqueous suspension of untreated titanium dioxide particles, wherein the pH is adjusted to at least 8, preferably to at least 9 (step a).
• the suspension has previously been subjected to wet grinding in an agitating mill, wherein the grinding media known in the field of practice, such as sand or zirconium oxide, can be used.
• the inventive method is carried out at a temperature of less than 80 ° C, preferably at 45 to 65 ° C, in particular at 55 to 65 ° C.
• phosphoric acid H 3 PO 4
• the phosphoric acid preferably has a concentration of about 75%.
• an alkaline or acidic aluminum component may be added to the suspension, for example sodium aluminate or aluminum sulfate, the pH at the end of step b) being preferably 3 or below, more preferably about 2 or below lies.
• step b) of untreated aluminum-doped titanium dioxide particles part of the aluminum was dissolved.
• Al 2 O 3 content of the main body of 1.4% by weight at the end of step b) at a pH of about 2
• an amount of about 0.2% by weight of aluminum is calculated Al 2 0 3 solved:
• Suspension preferably sodium aluminate.
• the pH at the end of step c) is preferably at least 5, in particular at least 7.
• step d) an acidic aluminum component is added, with a pH in the range from 4.5 to 7, preferably in the range from 5 to 6.
• a further aluminum oxide layer is applied to the titanium dioxide particles in a step e), for example by parallel addition of sodium aluminate and aluminum sulfate at a fixed pH of about 5 (so-called "fixed pH” method).
• a pH adjustment to about 6 to 7 takes place.
• the amount of phosphoric acid used in step b) is preferably from 1.0 to 5.0% by weight, in particular from 1.5 to 3.5% by weight and more preferably from 2.0 to 3.0% by weight, calculated as P 2 0 5 and based on Ti0 2 .
• the total amount of aluminum compounds added in steps c) and d) is preferably from 2.5 to 4.0% by weight, calculated as Al 2 O 3 and based on TiO 2 . To this amount is also optionally added before or during step b) alkaline or acidic
• the total amount of the aluminum compounds added in step b) to step e) is preferably 3.0 to 7.0% by weight, in particular 4.0 to 6.0% by weight, calculated as Al 2 O 3 1 5 and based on Ti0 2 .
• the aftertreated TiO 2 pigment is separated from the suspension by filtration methods known to those skilled in the art, and the resulting filter cake is washed to remove the soluble salts.
• Filter cake can be reduced by about 10%.
• the filter cake has a residual moisture content of at least 58% by weight (Moore filtration), whereas with the process according to the invention
• Method preferably can achieve residual moisture content of 52 wt .-% and less.
• the washed filter cake can be used to improve the light fastness of the pigment in the laminate before or during the subsequent drying a nitrate-containing compound, zB0 KN0 3 , NaN0 3 , Al (N0 3 ) 3 in an amount of 0.05 to 0.5 wt .-% calculated as N0 3 and based on pigment are added. Furthermore, the pigment in one of the
• Process steps to improve the flow properties of an organic compound are added from the series of those commonly used in the production of Ti0 2 pigments and which are known in the art, such as Polyalkohole5 (trimethylolethane, trimethylolpropane, neopentyl glycol).
• Polyalkohole5 trimethylolethane, trimethylolpropane, neopentyl glycol.
• the addition of such substances can also take place during the grinding.
• the treated pigment becomes a
• Heat treatment at 200 to 400 ° C, preferably 200 to 300 ° C for about 60 to 180
• the pigment produced by the process according to the invention exhibits improved graying stability with the same brightness and opacity compared with the comparative pigments and is optimally suitable for use in decorative paper.
• the pigment filter cake in comparison to DE 103 32 650 A1 lower residual moisture, resulting in further economic advantages.
• a wet-milled Ti0 2 suspension from the chloride process with a Ti0 2 concentration of 450 g / l, an aluminum doping corresponding to 1, 5 wt .-% Al 2 0 3 and a pH of 10 was 2.5 wt. % P 2 0 5 in the form of 75% H 3 P0 4 added.
• a pH of about 2 a was obtained.
• the suspension was adjusted in the next step by addition of aluminum sulfate (corresponding to 1, 1 to 1, 2 wt .-% Al 2 0 3 ) to a pH of 5. It was then 2.2 wt .-% Al 2 0 3 in the form of a parallel addition of aluminum sulfate and sodium aluminate solution mixed so that the pH was kept at 5 (fixed-pH method). Subsequently, the suspension was adjusted to a pH of 5.5 to 7 with the aid of an alkaline sodium aluminate solution.
• aluminum sulfate corresponding to 1, 1 to 1, 2 wt .-% Al 2 0 3
• the post-treated Ti0 2 suspension was filtered and washed by washing
• the washed filter paste became after addition of approximately Dried 0.18 wt .-% N0 3 as NaN0 3 in a spray dryer and then ground on a jet mill.
• the pigment produced contained the following aftertreatment elements expressed in the form of their oxides: 2.2% by weight of P 2 O 5 and 5.8% by weight of Al 2 O 3 , based in each case on the TiO 2 base body and 0.18% by weight. % N0 3 .
• Example 2 The procedure was as in Example 1 with the difference that in the step "fixed pH method" instead of 2.2 wt .-% Al 2 0 3 1, 0 wt .-% Al 2 0 3 in the form of the parallel addition of aluminum sulfate and sodium aluminate solution.
• the pigment produced contained the following after-treatment elements expressed in the form of their oxides: 2.3% by weight of P 2 O 5 and 4.9% by weight of Al 2 O 3 , based in each case on the TiO 2 base body and 0.18% by weight. % N0 3 . Comparative example
• a wet-milled TiO 2 suspension from the chloride process with a Ti0 2 concentration of 450 g / l, an aluminum doping corresponding to 1, 5 wt .-% Al 2 0 3 and a pH of 10 was 2.0 wt. % Al 2 0 3 added as sodium aluminate. This resulted in a pH of> 12. Thereafter, 2.5 wt .-% P 2 0 5 was added as a disodium hydrogen phosphate solution. The pH of the suspension remained> 2
• Suspension was adjusted in the next step by addition of aluminum sulfate (corresponding to 2.4 wt .-% Al 2 0 3 ) to a pH of 5. Subsequently, 0.9 wt .-% Al 2 0 3 in the form of a parallel addition of aluminum sulfate and sodium aluminate solution was added so that the pH was kept at 5. Subsequently, the suspension was adjusted to a pH of 6.8 with the aid of an alkaline sodium aluminate solution. The post-treated Ti0 2 suspension was filtered and washed by washing
• the washed filter paste was dried, after addition of about 0.18% N0 3 as NaN0 3 in a spray drier and then ground on a jet mill.
• the pigment produced contained the following after-treatment elements expressed in the form of their oxides: 2.1% by weight of P 2 O 5 and 6.0% by weight of Al 2 O 3 , based in each case on the TiO 2 base body and 0.18% by weight. % N0 3 . Test Methods and Test Results Laminate Division (Laboratory Scale)
• the titanium dioxide pigments 5 prepared according to Examples 1 and 2 and Comparative Example were incorporated in decorative paper and then with respect to their optical characteristics
• the titanium dioxide pigment to be tested was incorporated into pulp and produced sheets having a basis weight of about 80 g / m 2 and a Ti0 2 mass fraction of about 30 g / m 2 .
• the titanium dioxide content (ash in [%]) of a sheet was then determined. To determine the titanium dioxide content, a defined amount by weight of the produced paper was ashed with a high-speed asher at 900 ° C. The weight of the residue is used to calculate the mass fraction of Ti0 2 (ash in [%]). The following formula was used to calculate the ash content:
• Ash content [g / m 2 ] (ash [%] x basis weight [g / m 2 ]) / 100 [%]. 5 Further processing of the paper involved impregnation and compression into laminates.
• the sheet to be sealed was completely immersed in a melamine resin solution, then drawn between 2 squeegees to ensure a certain resin application, and then precondensed in a convection oven at 130 ° C.
• the sheet had a residual moisture content of from 5.7% to 6.2% by weight.
• the condensed sheets were soaked in phenolic resin
• the press packs were constructed as follows: decorative paper, white or black underlay paper, 6 core papers, 5 white or black underlay paper, decorative paper.
• the press packs were as follows constructed: decorative paper, 5 sheets of core paper, white underlay paper.
• the packages are pressed using a Wickert Type 2742 laminate press at one
• the measurement of the optical properties and the graying stability of the laminates was carried out using commercial equipment (spectrophotometer, xenotest device).
• the color values (CIELAB L * , -a * , -b * ) according to DIN 6174 are determined using the ELREPHO ® 3300 colorimeter over white or over black underlay paper.
• the opacity is a measure of the translucence or transmission of the paper.
• Test results The table shows the test results for laminates with the invention
• Pigments (Example 1 and 2) and with a comparative pigment (Comparative Example) were prepared. It can be seen that the laminates produced with the pigments according to the invention have a significantly higher graying stability with equal brightness and opacity values in comparison to a laminate which contains a pigment prepared according to the prior art. table

Landscapes

• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Inorganic Chemistry (AREA)
• Paper (AREA)
• Pigments, Carbon Blacks, Or Wood Stains (AREA)
• Inorganic Compounds Of Heavy Metals (AREA)

Priority Applications (12)

Applications Claiming Priority (2)

Publications (1)

Family

ID=45930645

Family Applications (1)

Country Status (18)

Cited By (4)

Families Citing this family (12)

Citations (7)

Family Cites Families (7)

• 2011
  • 2011-04-01 DE DE102011015856A patent/DE102011015856A1/de not_active Ceased
• 2012
  • 2012-03-21 KR KR1020137028518A patent/KR101900250B1/ko not_active Expired - Fee Related
  • 2012-03-21 MX MX2013011383A patent/MX2013011383A/es active IP Right Grant
  • 2012-03-21 MY MYPI2013701787A patent/MY162885A/en unknown
  • 2012-03-21 UA UAA201309612A patent/UA113054C2/uk unknown
  • 2012-03-21 JP JP2014501472A patent/JP5931172B2/ja active Active
  • 2012-03-21 RU RU2013148886/05A patent/RU2586563C2/ru active
  • 2012-03-21 AU AU2012237486A patent/AU2012237486B2/en not_active Ceased
  • 2012-03-21 CN CN201280017407.4A patent/CN103476877B/zh active Active
  • 2012-03-21 WO PCT/EP2012/001229 patent/WO2012130408A1/de not_active Ceased
  • 2012-03-21 PL PL12712223T patent/PL2694599T3/pl unknown
  • 2012-03-21 SI SI201231025T patent/SI2694599T1/sl unknown
  • 2012-03-21 EP EP12712223.2A patent/EP2694599B1/de active Active
  • 2012-03-21 BR BR112013025092-5A patent/BR112013025092B1/pt active IP Right Grant
  • 2012-03-21 ES ES12712223.2T patent/ES2633855T3/es active Active
  • 2012-03-26 US US13/429,512 patent/US8641870B2/en active Active
  • 2012-03-29 SA SA112330411A patent/SA112330411B1/ar unknown
  • 2012-03-30 TW TW101111227A patent/TWI608058B/zh not_active IP Right Cessation

Patent Citations (8)

Also Published As

Similar Documents

Legal Events