GB2114557A - Amorphous, layered silica particles of large specific surface area - Google Patents
Amorphous, layered silica particles of large specific surface area Download PDFInfo
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- GB2114557A GB2114557A GB08303427A GB8303427A GB2114557A GB 2114557 A GB2114557 A GB 2114557A GB 08303427 A GB08303427 A GB 08303427A GB 8303427 A GB8303427 A GB 8303427A GB 2114557 A GB2114557 A GB 2114557A
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- acid
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- mineral
- leached
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- 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
- C09C1/28—Compounds of silicon
- C09C1/30—Silicic acid
- C09C1/3009—Physical treatment, e.g. grinding; treatment with ultrasonic vibrations
- C09C1/3027—Drying, calcination
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/113—Silicon oxides; Hydrates thereof
- C01B33/12—Silica; Hydrates thereof, e.g. lepidoic silicic acid
- C01B33/18—Preparation of finely divided silica neither in sol nor in gel form; After-treatment thereof
- C01B33/187—Preparation of finely divided silica neither in sol nor in gel form; After-treatment thereof by acidic treatment of silicates
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/20—Silicates
- C01B33/32—Alkali metal silicates
-
- 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
- C09C1/28—Compounds of silicon
- C09C1/30—Silicic acid
-
- 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
- D21H19/00—Coated paper; Coating material
- D21H19/36—Coatings with pigments
- D21H19/38—Coatings with pigments characterised by the pigments
- D21H19/40—Coatings with pigments characterised by the pigments siliceous, e.g. clays
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/02—Amorphous compounds
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/20—Two-dimensional structures
- C01P2002/22—Two-dimensional structures layered hydroxide-type, e.g. of the hydrotalcite-type
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/50—Solid solutions
- C01P2002/52—Solid solutions containing elements as dopants
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/20—Particle morphology extending in two dimensions, e.g. plate-like
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/30—Particle morphology extending in three dimensions
- C01P2004/32—Spheres
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/50—Agglomerated particles
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/51—Particles with a specific particle size distribution
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
-
- 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
-
- 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
- C01P2006/12—Surface area
-
- 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
- C01P2006/14—Pore volume
-
- 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
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Dispersion Chemistry (AREA)
- Silicon Compounds (AREA)
- Silicates, Zeolites, And Molecular Sieves (AREA)
- Paper (AREA)
Abstract
The invention provides amorphous, layered, porous silica particles having a large specific surface area and containing less than 15% by weight of impurity cations. Such particles are prepared by leaching a finely-ground mica-type silicate mineral with an acid. Owing to their purity and porosity, such particles can be used as paper coating pigments.
Description
SPECIFICATION
Amorphous, layered silica particles of large specific surface area
The present invention relates to amorphous, layered, porous silica particles having a large specific surface area, a method for preparing such amorphous, layered silica particles by leaching a finelyground layered silicate mineral by means of an acid in order to dissolve the ions of its octahedron layer, and the use ofthe amorphous, layered, porous silica particles thus obtained.
Silica, SiO2.XH2O, appears in crystalline, amorphous, hydroxylated and hydrolysed forms. With the exception of silica of plants and siliceous earth, the amorphous silicas in nature are impure.
It is previously known to prepare synthetically amorphous silica particles which have a very large specific surface area and which can, furthermore, be obtained in a very pure state. Precise control of the synthesis conditions has, however, proven to be difficult, and therefore it is difficult to obtain synthetic silica particles having certain specific properties. The production methods are therefore complicated, and the synthetic amorphous silica particles thereby obtained are very expensive.
The object of the present invention is thus to produce amorphous, porous silica particles which are at least as pure and have at least as large a specific surface area as the above-mentioned previously known synthetically prepared amorphous silica particle, but their preparation is simpler and less expensivethan previously.
It is previously known that certain layered silicates, such as natural clays, have absorptive properties which can be improved by a thermal treatment or by leaching part of the cations by means of acids. A thermal treatment removeswaterfrom the pores of silicate minerals, whereby their porosity and specific surface area increase. An acid treatment, for its part, dissolves the ions of an octahedron layer, whereby the layered silicate becomes porous and electrochemically more active as the cation sites are taken up by hydrogen ions. However, the layered structure of such a silicate collapses at the latest at the stage when about 85% by weight of the octahedron layer has dissolved, at which time the porosity and large specific surface area produced by means of leaching disappear.The use of porous materials of this type is thus limited mainly to various absorption applications, in which very high purity is not required ofthe absorbing material itself.
The present invention provides an amorphous, layered porous silica particle which has a large specific surface area, and more particularly a specific surface area at least as large as that ofthe layered silica particles prepared from the above-mentioned layered silicates, but has a higher degree of purity, and in particular contains less than 15% by weight of cations.
It has thus been suprisingly observed that it is possible to prepare amorphous, layered silica particles having a large specific surface area and a high degree of purity, by reaching a mica-type silicate mineral by means of an acid in orderto dissolve the ions of its octahedron layer in such a way that the amount of impurity cations remaining is less than 15% by weight. It was surprising to observe that the layered structure of such a mica-type silicate mineral did not collapse even though practically all cations were leached out from the octahedron layer.By means of the invention it has thus been possible to combine the advantageous properites of the previously known amorphous synthetic silica particles and the layered silica particles prepared from natural clays, and at the sametimeto avoid their adverse properties, i.e. the high price ofthe amorphous synthetic silica particles and the relatively high degree of impurity of the amorphous, layered silicate particles.
Amorphous, layered, porous silica particles prepared by the method according to the invention can thus be used for applications in which a very high degree of whiteness is required, e.g. as a paper coating pigment.
The typical properties of the product to which the invention relates include:
1. layered, sheet-like particle form
2. large specificsurface area, at minimum 300 m2/g 3. large pore volume, at minimum 0.25 cm3/g
4. pores mainly micro- and meso-pores
5. purity above 85%; when necessary, even above 99.5%
6. whiteness
7. reactivity
All ofthe above properties can be adjusted by means of the preparation conditons.
When amorphous, layered silica particles according to the invention are prepared, a mica-type silicate mineral is leached advantageoulsy in a mineral acid ora mixture of mineral acids, in which case an acid excess of at least 10% by weight is preferably used in proportion to the cations ofthe octahedron layer. The leaching is preferably carried out in several stages and at an elevated temperature, preferably about 100-105"C, using a mineral acid ora mineral acid mixture having a concentration of 5-50%, preferably 10-45%, by weight. The leached, finely-ground layered silica is washed and, when necessary, wet-ground and/or dried. The drying can be carried out by spray drying, whereby spherical agglomerates are obtained, in which the layered property of the primary particles is, however, retained.
Very good amorphous, layered silica particles having a large specfic surface area have been obtained by leaching phlogopite or biotite, which are 3-layer silicates having a trioctahderal metal hydroxide layer between tetrahedral silicic acid layers.
Layered silica particles according to the invention are prepared from mica-type silicate mineral such as phlogopite by leaching ground phlogopite by means of a mineral acid our a mixture of mineral acids, until the desired degree of dissolving has been reached.
The leaching conditions, such as the type, concentration, amount, temperature and mixing ofthe acid, can be varied, depending on the equipment available, the prices of the various acids and the quality of the desired final product. Factors speeding up the dis solving include high temperature, strong acid, excess acid, reduced particle size of the phlogopite, and oxidizing conditions. Complete dissolving of the cations of coarse phlogopite (d50 > 1 mm) takes a few days at normal temperature, i.e. the reaction temperature, and a few hours at 1 00 C. In addition, it is advantageous to use an acid excess of at least 10%.
Even though itis possible to leach phlogopite under many types of conditions, certain conditions are economically and technologically more profitable.
The use of dilute acids, less than 5%, diminishes the economical exploitation ofthe dissolved metals or the reuse of the acid, whereas the slurry obtained for leaching when using strong acids, over 50%, is too thick and difficult to handle. On an industrial scale it is worth while to use a multiple-stage leach operated according to the countercurrent principle, in which casethe amount of acid can be minimized and the leaching time and the temperature can be regulated in the desired manner. In selecting the mixing method it should be taken into account that the product obtained breaks easily. A product ground to a high degree causes treatment difficulties during the final stages of the leaching process, i.e. the washing and the filtration. Washing the final product clean of the mother liquor can be carried out either by slurrying or as a filter cake.In washing a cake, the efficiency of the wash, and thereby also the number ofwashings and the amount of water, are substantial ly governed by the density ofthe cake. According to experience, the flow resistance of a cake pressed/ suction-dried to a compact state is very high.
If the above-mentioned factors are taken into consideration, an economical and technologically high usable method of preparing the product accod ingto the invention is as follows: Phlogopite is leached using 10-45% mineral acid, most advan tageously nitric acid or a mixture of nitric acid and sulfuric acid, in a multiple-stage system operated according tothe countercurrent principle and atthe reaction temperature until the desired degree of dissolving has been reached. At each leaching stage the necessary mixing is used, taking into consideration the degree of grinding of the product. The mother liquorisfiltered off, taking precautions not to compact the cake. The result ofthe filtration can be improved by blowing air through the cake.The wash is carried out in the manner of displacement wash, making sure that the cake is not pressed. The clean washed cake is pressed as dry as possible, to a moisture content usually over 50%, and is dried, and, when necessary also ground by means of a spray, ball, or rod mill. The particle size of the unground product is nearly the same as that ofthe initial material, phlogopite; the particle size of the product ground to a high degree is 95% less than 2 ,am, as measured by the settling method. If thd ground product is used as a slurry, it is advantageous to grind thefilter-dry product while wet, prior to drying, since the undried product is very easyto grind.The dried productwithstands mechanical treatment well.Wet- ground productslurry can be dried, for example, by means of a spray drier, whereby spherical particles are obtained which are better suited for certain purposes and in which the layered nature of the primary particles is, however, retained.
Owing to their purity and their large specific surface area, amorphous, layered silica particles accordingtotheinventioncan beusedforthesame purposes as the currently known synthetic silica particles, for example as a dulling agent in lacquers, a filler material in rubber, a special pigment in paper coatings, an adsorptive material, etc. Owing to their specific properties the layered, porous silica particles according to the invention are, however, better suited forcertain purposes such coatings than are the previously known synthetic silica particles. In addition, they can be used for creating certain specific properties when they are used as auxiliary pigments in paper coating.
Owing to their large reactive surface area, the layered silica particles according to the invention are aiso well suited for the production of various silicate compounds. They are readily soluble in warm sodium hydroxide at normal pressure. The conventional silicate production methods (sand + soda) consume a great amount of energy. When the layered and very pure silica particles according to the invention are used,the consumption of energy is considerably lower, in addition to which the price of the layered silica particles according to the invention is relatively low, and therefore, taking into account the savings of energy, they are aconomically profitable to useforthe production of silicates.
The invention is described below in greater detail with the aid of examples.
Example 1
60 g of phlogopite was slurred in 371.2 ml of 30-percent(byweight) nitric acid at room tempera
ture. The mixture was maintained at this temperature
while mixing. Samples were taken from the mixture at 4 hours, 1 day and 3 days. The undissolved solid was separated, washed and dried at 1 05 C. The specific surface area and the pore distribution ofthis product were analysed. The potassium, iron, magnesium and aluminum ofthefiltratewere analysed .The results are presented in Table 1.
Table 1
Dissolving of the cations of phlogopite at 25"C in 30-percent (byweight) nitric acid.
Table 1
Dissolving of the cations of phlogopite at 25 OC in
30-percent (by weight) nitric acid
Leaching X Fe,Mg, Al SpET time r 8 e m2/5 cm m2/g cin /g
4 h 77 29 145 0.139
1 d 88 77 435 0.271
3 d 99 96 622 0.432
Example 2
30 g ofphlogopitewasslurried in 185.6 ml of
30-percent (by weight) nitric acid at 1 00 C. Samples
were taken from the mixture at 10 minutes, 20
minutes and 5 hours. The sample was filtered,
washed and dried. Potassium, magnesium, iron and
aluminum of the filtrate were analysed. The specific
surface area and the pore distribution ofthe solid
material were measured. The results are presented in
Table 2.
Table 2
The dissolving ofthe cations of phlogopite in
30-percent (by weight) nitric acid at 1 000C Table 2
The dissolving of the cations of phlogopite in 30-percent (by weight) nitric acid at 100 OC Leaching K Fe, Mg, Al 5 V time BET TOT m2/g cm3/g 10 min 86 85 544 0.312 20 " 94 93 622 0.381
5 h 100 100 396 0.345
Example 3
Phlogopite was leached by means of 30-percent (by weight) nitric acid at 25"C until all cations had dissolved. The residue obtained consisted of white (whiteness 97% of magnesium oxide) layered silica particles, which were filtered and washed usiing water.The filter cake was bathed into a disperser and was dispersed for about 45 minutes, whereby a slurry was obtained in which the particle size measured by means of a pipette contrifuge was about 30% less than 2 ,am. This slurry was ground in a bead mill,wherebyaslurrywasobtained inwhich the particle size was about 70% less than 2 jim, and this slurry was mixed with purified waste gypsum at a weight ratio of 1:10 and was ground into a pigment mixture in a bead mill.
Mixture pigments were also prepared, with gypsum, from sodium aluminum silicate and barium suifate, which are conventionally used for paper coating, at mixing ratios of 1:9 and 1:6. Coating pastes were prepared from thethree mixture pigments and from gypsum alone. A reference paste was prepared from a calcium carbonate pigment of which at least 85% by weight had a particle size less than 2 jim. Of the gypsum, at least 40% by weight had a particle size lessthan2jim. In the accompanying figuretheopacityvaluesmeasuredfrom coated papersamples are presented as a function of the amount of coating of the above-mentioned pastes.It can be seen from thefigurethat, even though the gypsum contains less silica than it contains sodium aluminum silicate or barium silicate, clearly the highest degree of opacity is obtained using a mixture of layered silica and gypsum according to the invention.
Example 4
Dull-finish coating of wood-free base paper was experimented with using wet-ground gypsum pigment both alone and together with certain auxiliary pigments. The results were compared with the results obtained using commercial calcium carbonate pigments.
The experiments were performed by means of a
Dixon coating apparatus using the blade coating method, and 12 parts by weight of styrene butadiene latex and 1.5 parts by weight of carboxy-methyl cellulose were used as bonding agents in the coating pastes, the total amou nt of the pig ments being 100 parts by weight. The pH value of the pastes was 7.5.
The following pigment alternatives were stdied:
1. Wet-g rou nd calcium carbonate, over85% by weight less than 2 pm.
2. Wet-groundgypsum,40% byweight less than 2jim.
3. 85 parts byweightofgypsum + 15partsby weight of a commercial barium sulfate pigment.
4. 90 parts byweight of gypsum + 10partsby weight of a commercial sodium aluminum silicate pigment.
5. 10% byweightofa layeredsilica pigment according to the invention mixed with gypsum, the mixture being ground bythewet method under conditions as close as possible to those for the gypsum of point 2. A study using a microscope showed that the silica particles where sheet-like, most of them having a particle size less than 2 jim, and the gypsum was similartothat in point2.
The test papers were calendered under mutually simila r conditio ns. The gloss of the test sam ples (Hunter 75Q) is presented as a function ofsmoothness (Fogra 2.54 MPa) in Figure 2. The numbering of the curves in Figure 2 corresponds to the numbering of the above-mentioned pigment alternatives.
It was shown that the layered silica pigment according to the invention has an effect which facilitatesthecalendering and increases the smoothness of paper. It can, however, be seen in Figure 2 that, when the layered silica pigment according to the invention was used, the gloss ofthe paper did not increase in the normal manner in spite ofthe increased smoothness, even though the pigment was finely-divided and had a sheet-like particle shape.
This is a desired property in various dull-finish paper applications, such as base paper or base cardboard forwallpaper.
In addition, it was observed that an unexpectedly great improvement in the opacity values of paper was achieved using the new layered silica pigment, as seen in Figure 1.
In addition to all this, the new layered silica pigment absorbs copying color, and when it was used as an auxiliary pigment it was possible to produce a clearly readable trace on the copy.
Example 5
The usability ofthe test papers described in the previous examples as sheets receiving copying color was tested by writing on the sheets through conventional self-copying bankforms. The results shown in
Table 3were thereby obtained. The numering ofthe sample sheets corresponds to the numbering ofthe curves in Figure 2.
Table 3
Sample sheet Trace on the copy 1 No trace 2 No trace 3 No trace 4 Hardly readable trace 5 Clearly readable trace
Claims (14)
1. An amorphous, layered, porous silica particle having a large specific surface area and containing less than 15% by weight of cations.
2. Asilica particle according to claim 1, having a specific surface area of at least 300 m2/g, a purity of at least 99.5%, and a whiteness of at least 95% of that of magnesium oxide.
3. A method of preparing amorphous, layered silica particles having a large specific surface area which comprises leaching a finely ground mica-type silicate mineral with an acid to dissolve the ions of its octahedron layer.
4. A method according to claim 3, in which the mica-type silicate mineral is leached by means of a mineral acid or a mixture of mineral acids.
5. A method according to claim 4 in which the acid is used in an acid excess of at least 10% by weight in relation to the cations of the octahedron layer.
6. A method according to claim 4 or Sin which the mica-type silicate mineral is leached in several stages and atan elevated temperature using a mineral acid ora mineral acid mixture having a concentration of 5-50% by weight.
7. A method according to claim 6 in which the mineral acid has a concentration of 10.4% by weight.
8. A method according to any of claims 4-7, in which the mica-type silicate mineral is leached with nitric acid or a mixture of nitric acid and sulfuric acid.
9. A method according to any of claims 3-8, in which finely-ground phlogopite or biotite is leached.
10. A method according to any of claims 3-9, in which the leached, finely-ground layered silica is washed and furtherwet-ground, when necessary, before drying.
11. A method according to claim 10 in which the leached, finely-ground, layered silica is spray-dried to form spherical agglomerates.
12. A method according to claim 3 substantially as hereinbefore described.
13. Amorphous layered silica when produced by the method of any of claims 3 to 12.
14. Paper comprising, as a coating pigment, amorphous layered silica as claimed in claim 1,2 or 13.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FI820487A FI66821C (en) | 1982-02-12 | 1982-02-12 | AMORFA SKIKTADE KISELDIOXIDPARTIKLAR MED STOR SPECIFIK YTA SAETT ATT FRAMSTAELLA DESSA SAMT DERAS ANVAENDNING |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB8303427D0 GB8303427D0 (en) | 1983-03-16 |
| GB2114557A true GB2114557A (en) | 1983-08-24 |
| GB2114557B GB2114557B (en) | 1985-08-29 |
Family
ID=8515117
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB08303427A Expired GB2114557B (en) | 1982-02-12 | 1983-02-08 | Amorphous layered silica particles of large specific surface area |
Country Status (6)
| Country | Link |
|---|---|
| DE (1) | DE3304298A1 (en) |
| FI (1) | FI66821C (en) |
| FR (1) | FR2521575B1 (en) |
| GB (1) | GB2114557B (en) |
| NO (1) | NO156645C (en) |
| SE (1) | SE459858B (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0287354A1 (en) * | 1987-04-14 | 1988-10-19 | Kemira Oy | Coated silicate particles |
| EP0325484A1 (en) * | 1988-01-22 | 1989-07-26 | Kemira Oy | A colored nacreous pigment and a method for its preparation |
| US4915923A (en) * | 1986-06-13 | 1990-04-10 | Mizusawa Industrial Chemicals, Ltd. | Filler for ink jet recording paper |
| FR2699162A1 (en) * | 1992-12-10 | 1994-06-17 | Luzenac Talc | Method for manufacturing a microporous lamellar silica with a high specific surface, and silica obtained. |
| WO1999022860A1 (en) * | 1997-11-05 | 1999-05-14 | Engelhard Corporation | Mesoporous silicoaluminate products and production thereof by controlled acid extraction of aluminum from calcium bentonite clay |
| WO2000005452A1 (en) * | 1998-07-22 | 2000-02-03 | Security Transfer B.V. | Paint and paper coated with said paint |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116440855B (en) * | 2023-06-16 | 2023-09-05 | 格林斯达(北京)环保科技股份有限公司 | Purification material and preparation method and application thereof |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA679192A (en) * | 1964-02-04 | Bedard Laurent | Porous silica from micaceous minerals and method of producing it | |
| US1898774A (en) * | 1931-01-26 | 1933-02-21 | William J Mohr | Treatment of vermiculite and the like |
| DE2036892A1 (en) * | 1970-07-24 | 1972-02-03 | Huber, Dr. Otto, 8022 Grunwald | Lacquers - for surface finishing of paper |
| FR2122696A5 (en) * | 1971-01-20 | 1972-09-01 | Raffinage Cie Francaise |
-
1982
- 1982-02-12 FI FI820487A patent/FI66821C/en not_active IP Right Cessation
-
1983
- 1983-02-08 GB GB08303427A patent/GB2114557B/en not_active Expired
- 1983-02-09 DE DE19833304298 patent/DE3304298A1/en not_active Ceased
- 1983-02-09 FR FR8302056A patent/FR2521575B1/en not_active Expired
- 1983-02-09 SE SE8300676A patent/SE459858B/en not_active IP Right Cessation
- 1983-02-11 NO NO830475A patent/NO156645C/en unknown
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4915923A (en) * | 1986-06-13 | 1990-04-10 | Mizusawa Industrial Chemicals, Ltd. | Filler for ink jet recording paper |
| EP0287354A1 (en) * | 1987-04-14 | 1988-10-19 | Kemira Oy | Coated silicate particles |
| US4883539A (en) * | 1987-04-14 | 1989-11-28 | Kemira Oy | Coated silicate particles |
| EP0325484A1 (en) * | 1988-01-22 | 1989-07-26 | Kemira Oy | A colored nacreous pigment and a method for its preparation |
| FR2699162A1 (en) * | 1992-12-10 | 1994-06-17 | Luzenac Talc | Method for manufacturing a microporous lamellar silica with a high specific surface, and silica obtained. |
| WO1994013585A1 (en) * | 1992-12-10 | 1994-06-23 | Talc De Luzenac | Method for producing microporous laminar silica |
| WO1999022860A1 (en) * | 1997-11-05 | 1999-05-14 | Engelhard Corporation | Mesoporous silicoaluminate products and production thereof by controlled acid extraction of aluminum from calcium bentonite clay |
| WO2000005452A1 (en) * | 1998-07-22 | 2000-02-03 | Security Transfer B.V. | Paint and paper coated with said paint |
Also Published As
| Publication number | Publication date |
|---|---|
| FI66821B (en) | 1984-08-31 |
| GB8303427D0 (en) | 1983-03-16 |
| NO830475L (en) | 1983-08-15 |
| SE8300676D0 (en) | 1983-02-09 |
| NO156645C (en) | 1987-10-28 |
| DE3304298A1 (en) | 1983-08-25 |
| FI820487L (en) | 1983-08-13 |
| GB2114557B (en) | 1985-08-29 |
| FR2521575A1 (en) | 1983-08-19 |
| SE459858B (en) | 1989-08-14 |
| FR2521575B1 (en) | 1988-06-24 |
| FI66821C (en) | 1984-12-10 |
| SE8300676L (en) | 1983-08-13 |
| NO156645B (en) | 1987-07-20 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 19930208 |