EP0000415B1 - Procédé pour la préparation de suspensions aqueuses contenant au moins 65% en poids de carbonate de calcium - Google Patents
Procédé pour la préparation de suspensions aqueuses contenant au moins 65% en poids de carbonate de calcium Download PDFInfo
- Publication number
- EP0000415B1 EP0000415B1 EP78200085A EP78200085A EP0000415B1 EP 0000415 B1 EP0000415 B1 EP 0000415B1 EP 78200085 A EP78200085 A EP 78200085A EP 78200085 A EP78200085 A EP 78200085A EP 0000415 B1 EP0000415 B1 EP 0000415B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- calcium carbonate
- process according
- polyelectrolyte
- alkali metal
- concentrate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D17/00—Pigment pastes, e.g. for mixing in paints
- C09D17/004—Pigment pastes, e.g. for mixing in paints containing an inorganic pigment
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
- C01F11/00—Compounds of calcium, strontium, or barium
- C01F11/18—Carbonates
- C01F11/182—Preparation of calcium carbonate by carbonation of aqueous solutions and characterised by an additive other than CaCO3-seeds
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
- C01F11/00—Compounds of calcium, strontium, or barium
- C01F11/18—Carbonates
- C01F11/182—Preparation of calcium carbonate by carbonation of aqueous solutions and characterised by an additive other than CaCO3-seeds
- C01F11/183—Preparation of calcium carbonate by carbonation of aqueous solutions and characterised by an additive other than CaCO3-seeds the additive being an organic compound
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
- C01F11/00—Compounds of calcium, strontium, or barium
- C01F11/18—Carbonates
- C01F11/185—After-treatment, e.g. grinding, purification, conversion of crystal morphology
-
- 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
- C09C1/02—Compounds of alkaline earth metals or magnesium
- C09C1/021—Calcium 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
- D21H19/00—Coated paper; Coating material
- D21H19/36—Coatings with pigments
- D21H19/38—Coatings with pigments characterised by the pigments
- D21H19/385—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
- D21H19/00—Coated paper; Coating material
- D21H19/36—Coatings with pigments
- D21H19/44—Coatings with pigments characterised by the other ingredients, e.g. the binder or dispersing agent
- D21H19/52—Cellulose; Derivatives thereof
-
- 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
- C01P2004/60—Particles characterised by their size
- C01P2004/62—Submicrometer sized, i.e. from 0.1-1 micrometer
Definitions
- the subject of the present invention is the preparation of concentrated aqueous suspensions of calcium carbonate, by crystallization of calcium carbonate in an aqueous medium.
- concentrated aqueous generally containing 65 to 80% by weight of crystals.
- This known method has the disadvantage of requiring an expensive grinding operation. This is in fact imposed by the need to break up the numerous coarse agglomerates of calcium carbonate crystals present in the wet calcium carbonate concentrate. In addition to its unfavorable influence on the cost of the process, this grinding operation has the drawback of giving rise to the formation of calcium carbonate fines, which are generally not suitable as a filler.
- the filter cakes obtained by this known process are in the form of aqueous suspensions of fine crystals, very suitable as a filler in stationery, in plastics and in paints.
- concentration of calcium carbonate crystals in these aqueous suspensions is generally insufficient to allow them to be stored and handled economically, so that it is necessary to concentrate them by evaporating them.
- the Applicant has now found that by carrying out the crystallization under special conditions, it is possible to obtain concentrated aqueous suspensions of fine and regular crystals of calcium carbonate, generally containing more than 65% by weight of dry matter, without requiring grinding or evaporation.
- the invention therefore relates to a process for the preparation of aqueous suspensions containing at least 65% by weight of calcium carbonate, according to which crystalline calcium carbonate in dilute aqueous medium is separated from the dilute aqueous suspension of calcium carbonate resulting, a wet calcium carbonate concentrate and said calcium carbonate concentrate is fluidized and homogenized in the presence of a dispersing agent, the crystallization of the calcium carbonate being carried out in the presence of a water-soluble polyelectrolyte and the separation of the wet concentrate from the diluted aqueous suspension being carried out by mechanical means.
- polyelectrolyte is understood to mean a polymeric substance whose monomeric units have ionizable groups, and which is composed, on the one hand, of a macroion formed from ionic groups of the same sign, linked together by chemical bonds and, on the other hand, a series of counterions of charge opposite to that of the macroion (Encyclopedia of Polymer Science and Technology - John Wiley & Sons - 1969 - Vol. 10, p. 781).
- polyacids or their salts, which are polyelectrolytes which, by dissociating, give rise to polymeric anions (polyanions) and to elementary cations such as, for example, protons or monovalent cations derived from alkali metals (Op. cit., p. 781 to 784).
- Polyacids with a weak acid character are preferably used, defined as being polyacids whose pK, measured on a 0.01 N solution in pure water, is greater than 4, preferably 6 (Op. Cit., p. 787 to 788).
- Polyacids with a weak acid character which are very suitable in the context of the invention are those derived from polymers comprising at least one carboxylic group per 10 carbon atoms.
- polyacids which can be used in the process according to the invention mention may in particular be made of polymers derived from acrylic, methacrylic and alpha-hydroxyacrylic acids, copolymers of maleic acid, carboxylated derivatives of cellulose ethers, and their alkali metal salts.
- particularly advantageous polyelectrolytes include the alkali metal salts of polyacrylic acids and their derivatives such as poly-alpha-hydroxyacrylic acids, more particularly that known under the name of Polysel CA (BASF) which is based on sodium polyacrylate.
- BASF Polysel CA
- the crystalli sation of calcium carbonate in an aqueous medium can be carried out by any means known per se, for example by reacting a solution of ammonium carbonate or alkali metal.
- the crystallization of calcium carbonate is advantageously carried out by carbonating a milk of lime, preferably by means of a gas containing CO 2 .
- a lime milk titrating between 25 and 350, preferably between 50 and 250, kg of CaO per m 3 which is prepared in a manner well known per se , by dispersing quicklime in water from the calcination of limestone in a lime kiln.
- a gas poor in C0 2 for example boiler fumes containing 5 to 15% by volume of C0 2 .
- a gas rich in C0 2 containing more than 30% of CO z , such as the gas recovered from lime kilns.
- the respective amounts of milk of lime and carbonation gas must be sufficient to ensure as complete carbonation of the lime as possible. These quantities obviously depend on the respective concentrations of the milk of lime and of the gas, as well as on the working conditions, and they can, in each particular case, be easily established by experience.
- the crystallization is preferably carried out at a temperature of the order of 25 to 60 ° C., for example close to 30 to 50 ° C.
- the amount of polymer incorporated into the aqueous medium depends on various factors, including the working conditions during crystallization and the nature of the polymer used; it can be easily determined by experience, in each case.
- the calcium carbonate is crystallized by carbonating a lime milk
- calcium carbonate concentrate is understood to mean a wet cake of calcium carbonate, which has been formed from the abovementioned dilute aqueous suspension of calcium carbonate.
- essentially mechanical separation means are used.
- a mechanical separation means it is possible, for example, in accordance with the invention, to use filtration, wringing or decantation of the dilute aqueous suspension, which are techniques well known per se. As a variant, it is also possible to combine two or more separate mechanical separation means.
- filtration which is a technique well known per se, the filter cake collected on the filter then constituting the aforementioned wet concentrate.
- filtration of the diluted suspension is advantageously carried out under pressure, for example between 0.5 and 15 kg / cm 2 , and it is optionally followed by compression of the filter cake under a pressure between 1 and 20 kg / cm 2 and a sweep by a current of air under a pressure of 0.5 to 6 kg / cm 2.
- the temperature at which filtration is carried out as well as any compression and sweeping is not have not been shown to have a significant influence on the filtration result.
- it can for example be carried out between 15 and 50 ° C, advantageously at room temperature.
- the fluidization of the calcium carbonate concentrate consists in subjecting it to mechanical work which transforms it into a fluid, pumpable aqueous suspension. It is generally carried out, in a manner known per se, by mixing the concentrate, for example by means of a paddle, disc or rotary cone mixer.
- the homogenization has the function of ensuring an efficient, homogeneous dispersion of the calcium carbonate crystals in the above-mentioned fluid aqueous suspension resulting from the fluidization operation. It is generally obtained by subjecting it to turbulence or intense shearing work by means of a high-speed disperser, for example of the paddle, disc or knife type.
- the fluidization and the homogenization are preferably carried out separately.
- the function of the dispersing agent used during fluidization and homogenization is to facilitate the dispersion of the calcium carbonate crystals, by avoiding the formation of crystal agglomerates.
- It can for example consist of an inorganic dispersing agent, such as the commercial dispersing agent known under the name of Calgon (Calgon Corp.), which is based on polyphosphate of alkali metal.
- the dispersing agent can also consist, at least partially, of an organic dispersing agent, for example a dispersing agent chosen from polyelectrolytes, preferably polyacids.
- dispersing agents which have been found to be particularly effective are those known as Polysel CA (BASF) which is a dispersing agent based on sodium polyacrylate and die Dispagil (Rhône-Progil) which is a dispersing agent based on polyphosphate and alkali metal polyacrylate.
- BASF Polysel CA
- Rhône-Progil die Dispagil
- the dispersing agent is preferably added to the calcium carbonate concentrate before carrying out the fluidization and homogenization. It can optionally be added to the dilute aqueous suspension of calcium carbonate, before separation of the calcium carbonate concentrate. However, it has been observed in practice that it is preferable to add the dispersing agent to the calcium carbonate concentrate, after having separated it from the aqueous suspension, since this results, all other things being equal, a decrease in the amount of dispersing agent required.
- the amount of dispersing agent used to fluidize and homogenize the calcium carbonate concentrate depends on various factors, including the nature of the dispersing agent, the particle size of the calcium carbonate crystals and the calcium carbonate content of the concentrate. It can be easily determined by experience in each case. Generally, it is advantageously between 2 and 10 g, preferably 4 and 8 g, per kg of calcium carbonate from the concentrate.
- the process according to the invention makes it possible to obtain easily, quickly and economically, concentrated, stable aqueous suspensions of regular crystals of calcium carbonate, generally containing at least 65%, preferably from 68 to 75%, by weight of crystals, without the need for expensive evaporation treatment or grinding.
- These co-centered suspensions lend themselves well to long-term storage and handling:, without their stability being affected.
- the calcium carbonate crystals they contain are well formed and regular and are well suited as a filler in stationery, paints and in the manufacture of plastics.
- a milk of lime was carbonated with a gas containing CO 2 .
- the dilute aqueous suspension of calcium carbonate thus obtained was then filtered under a maximum pressure of 4.5 kg / cm 2 , the filter cake obtained was compressed under a maximum pressure of 17 kg / cm 2 to wring it out, then subjected to an air sweep under pressure equal to 5.3 kg / cm 2 for 10 minutes, thus providing a wet concentrate of calcium carbonate.
- This calcium carbonate concentrate was then fluidized and then homogenized by passing successively through a kneader and then through a disperser, thus providing an aqueous suspension of calcium carbonate.
- Examples 1 and 2 relate to tests in accordance with the invention.
- Polysel CA which is a commercial polyelectrolyte based on sodium polyacrylate, was introduced into the milk of lime, which titrated approximately 120 kg of CaO per m 3 .
- the amount of Polysel CA introduced into the milk of lime was adjusted so that it corresponds approximately to 2.5 g of Polysel CA per kg of crystallized calcium carbonate.
- the milk of lime was then carbonated with a gas containing between 23 and 27% of CO 2 , at a rate of 1350 m 3 / h, for 7 h 15 min. The temperature was maintained at 37 ° C.
- the calcium carbonate concentrate collected on the filter was fluidized and homogenized in the presence of Calgon which is a commercial dispersing agent based on sodium polyphospliate. 7 g of Calgon were used per kg of calcium carbonate in the concentrate. There was thus obtained a concentrated aqueous suspension containing 68% of regular crystals of calcium carbonate. This aqueous suspension remained stable for more than 30 days.
- Example 1 The test of Example 1 was repeated, using a milk of lime titrating about 120 kg of CaO per m 3 and a gas containing between 29 and 32% of CO2 The carbonation, carried out at 32 ° C, lasted 7 h 35 min., with a gas flow of between 1200 and 1350 m 3 / h. The amount of Polysel CA was adjusted to correspond to 5 g per kg of calcium carbonate.
- the concentrated aqueous suspension of calcium carbonate obtained contained 71.7% by weight of calcium carbonate crystals; it remained stable for more than 30 days.
- Example 3 On the other hand, immediately reveals the advantage of the process according to the invention which makes it possible to obtain easily, without evaporation, by simple filtration, stable aqueous suspensions containing at least 68% by weight of calcium carbonate crystals.
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Wood Science & Technology (AREA)
- Health & Medical Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
- Application Of Or Painting With Fluid Materials (AREA)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
LU77723 | 1977-07-11 | ||
LU77723A LU77723A1 (fr) | 1977-07-11 | 1977-07-11 | Procede pour la preparation de suspensions aqueuses concentrees de carbonate de calcium |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0000415A1 EP0000415A1 (fr) | 1979-01-24 |
EP0000415B1 true EP0000415B1 (fr) | 1981-04-29 |
Family
ID=19728635
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP78200085A Expired EP0000415B1 (fr) | 1977-07-11 | 1978-07-07 | Procédé pour la préparation de suspensions aqueuses contenant au moins 65% en poids de carbonate de calcium |
Country Status (12)
Country | Link |
---|---|
US (1) | US4242318A (ru) |
EP (1) | EP0000415B1 (ru) |
JP (1) | JPS5418498A (ru) |
AT (1) | AT372695B (ru) |
BG (1) | BG49609A3 (ru) |
DE (1) | DE2860643D1 (ru) |
DK (1) | DK308478A (ru) |
ES (1) | ES471586A1 (ru) |
FI (1) | FI62272C (ru) |
IN (1) | IN147648B (ru) |
IT (1) | IT1099568B (ru) |
LU (1) | LU77723A1 (ru) |
Families Citing this family (29)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3004611A1 (de) * | 1980-02-08 | 1981-08-13 | Hoechst Ag, 6000 Frankfurt | Hochkonzentrierte fuellstoffslurries |
JPS5826031A (ja) * | 1981-08-05 | 1983-02-16 | Mitsubishi Gas Chem Co Inc | 分散性の良い炭酸カルシウムの製造方法 |
DE3275717D1 (en) * | 1982-11-10 | 1987-04-23 | Allied Colloids Ltd | Calcium carbonate dispersions |
GB8305346D0 (en) * | 1983-02-25 | 1983-03-30 | Ciba Geigy Ag | Particulate calcium carbonate |
US4756897A (en) * | 1986-06-23 | 1988-07-12 | Kerr-Mcgee Corporation | Process for preparing concentrated byproduct nitrate solutions |
US4732748A (en) * | 1986-12-10 | 1988-03-22 | Cyprus Mines Corporation | Finely divided calcium carbonate compositions |
US4888308A (en) * | 1987-02-10 | 1989-12-19 | Chemical Products Corporation | Glass manufacture using dense, unsintered, granular alkaline earth metal carbonates |
US5000871A (en) * | 1987-06-24 | 1991-03-19 | Maruo Calcium Company Limited | Gycol dispersion of calcium carbonate |
US5275650A (en) * | 1987-10-23 | 1994-01-04 | Coatex S.A. | Agent for grinding lime to augment its reactivity |
US5181662A (en) * | 1989-01-27 | 1993-01-26 | Coatex S.A. | Process for grinding calcium carbonate in aqueous media |
US5593488A (en) * | 1995-08-24 | 1997-01-14 | Ecc International Inc. | Acid resistant calcium carbonate composition and uses therefor |
US5531821A (en) * | 1995-08-24 | 1996-07-02 | Ecc International Inc. | Surface modified calcium carbonate composition and uses therefor |
US5593489A (en) * | 1995-10-20 | 1997-01-14 | Ecc International Inc. | Acid resistant carbonate composition containing an aluminum or magnesium hydroxide methods of preparation and uses therefor |
US5711799A (en) * | 1996-03-13 | 1998-01-27 | Ecc International Inc. | Acid tolerant calcium carbonate composition and uses therefor |
US5653797A (en) * | 1996-04-26 | 1997-08-05 | National Gypsum Company | Ready mixed setting-type joint compound and method of making same |
KR100190596B1 (ko) * | 1996-05-03 | 1999-06-01 | 규 재 유 | 0.1-1.0 마이크로미터의 탄산칼슘 제조법 |
US6083317A (en) * | 1996-11-05 | 2000-07-04 | Imerys Pigments, Inc. | Stabilized calcium carbonate composition using sodium silicate and one or more weak acids or alum and uses therefor |
GB9624085D0 (en) * | 1996-11-20 | 1997-01-08 | Ecc Int Ltd | Precipitates and their production |
GB9627002D0 (en) * | 1996-12-27 | 1997-02-12 | Ecc Int Ltd | Dispersed aqueous suspensions |
US6228161B1 (en) * | 1996-12-30 | 2001-05-08 | Minerals Technologies Inc. | Use of calcium carbonate in an acidic aqueous media |
ATE261912T1 (de) | 1998-12-23 | 2004-04-15 | Imerys Minerals Ltd | Herstellung von konzentrierten carbonatsuspensionen |
US6251356B1 (en) | 1999-07-21 | 2001-06-26 | G. R. International, Inc. | High speed manufacturing process for precipitated calcium carbonate employing sequential perssure carbonation |
US7048900B2 (en) | 2001-01-31 | 2006-05-23 | G.R. International, Inc. | Method and apparatus for production of precipitated calcium carbonate and silicate compounds in common process equipment |
US6937153B2 (en) * | 2002-06-28 | 2005-08-30 | Appleton Papers Inc. | Thermal imaging paper laminate |
FR2894846B1 (fr) * | 2005-12-20 | 2008-02-01 | Coatex Sas | Utilisation de dispersants pour concentrer des matieres minerales dans l'eau, dispersions obtenues et leurs utilisations. |
US7468101B2 (en) * | 2006-08-17 | 2008-12-23 | Specialty Minerals (Michigan) Inc. | UV varnish gloss performance using novel pigment and process for making same |
EP2292701B2 (en) * | 2009-07-01 | 2017-01-25 | Omya International AG | Method for improving opacity |
JP5748763B2 (ja) | 2009-11-27 | 2015-07-15 | ビーエーエスエフ ソシエタス・ヨーロピアBasf Se | ポリマー含有被覆の製造方法 |
JP6296984B2 (ja) | 2011-10-05 | 2018-03-20 | ソルヴェイ(ソシエテ アノニム) | 沈降炭酸カルシウム粒子及びその使用 |
Family Cites Families (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2709160A (en) * | 1953-06-24 | 1955-05-24 | Wyandotte Chemicals Corp | Amine-coated calcium carbonate pigments |
US3245819A (en) * | 1962-07-30 | 1966-04-12 | Wyandotte Chemicals Corp | Stabilization of calcium carbonate slurries |
US3347624A (en) * | 1965-05-26 | 1967-10-17 | Diamond Alkali Co | Method of preparing calcium carbonate |
GB1204511A (en) * | 1967-03-14 | 1970-09-09 | English Clays Lovering Pochin | Improvements in or relating to pigments |
GB1285891A (en) * | 1968-10-15 | 1972-08-16 | English Clays Lovering Pochin | Improvements in or relating to the treatment of minerals |
BE755970A (fr) * | 1969-09-10 | 1971-02-15 | English Clays Lovering Pochin | Pigment mixte se composant d'un pigment a l'argile et d'un pigment au cabonate de calcium |
JPS5112319B2 (ru) * | 1972-08-01 | 1976-04-17 | ||
GB1447566A (en) * | 1974-02-14 | 1976-08-25 | Ici Ltd | Production of calcium carbonate |
US3945843A (en) * | 1974-07-22 | 1976-03-23 | Nalco Chemical Company | Acrylic acid copolymer as pigment dispersant |
GB1472701A (en) * | 1975-01-03 | 1977-05-04 | English Clays Lovering Pochin | Production of aqueous calcium carbonate suspensions |
LU71867A1 (ru) * | 1975-02-17 | 1977-01-05 |
-
1977
- 1977-07-11 LU LU77723A patent/LU77723A1/xx unknown
-
1978
- 1978-06-12 BG BG040051A patent/BG49609A3/xx unknown
- 1978-06-15 IN IN448/DEL/78A patent/IN147648B/en unknown
- 1978-06-21 FI FI781991A patent/FI62272C/fi not_active IP Right Cessation
- 1978-07-04 JP JP8140778A patent/JPS5418498A/ja active Granted
- 1978-07-07 EP EP78200085A patent/EP0000415B1/fr not_active Expired
- 1978-07-07 DE DE7878200085T patent/DE2860643D1/de not_active Expired
- 1978-07-10 ES ES471586A patent/ES471586A1/es not_active Expired
- 1978-07-10 AT AT0496878A patent/AT372695B/de not_active IP Right Cessation
- 1978-07-10 DK DK783084A patent/DK308478A/da not_active Application Discontinuation
- 1978-07-10 US US05/923,195 patent/US4242318A/en not_active Expired - Lifetime
- 1978-07-11 IT IT25558/78A patent/IT1099568B/it active
Also Published As
Publication number | Publication date |
---|---|
FI62272C (fi) | 1982-12-10 |
FI781991A (fi) | 1979-01-12 |
FI62272B (fi) | 1982-08-31 |
IT7825558A0 (it) | 1978-07-11 |
AT372695B (de) | 1983-11-10 |
JPS5418498A (en) | 1979-02-10 |
DK308478A (da) | 1979-01-12 |
US4242318A (en) | 1980-12-30 |
JPS6317771B2 (ru) | 1988-04-15 |
BG49609A3 (en) | 1991-12-16 |
ATA496878A (de) | 1983-03-15 |
EP0000415A1 (fr) | 1979-01-24 |
IN147648B (ru) | 1980-05-17 |
DE2860643D1 (en) | 1981-08-06 |
ES471586A1 (es) | 1979-01-16 |
LU77723A1 (fr) | 1979-03-26 |
IT1099568B (it) | 1985-09-18 |
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