Omya International Ag

Basf Se Corporation

Ciba Specialty Chemicals Corporation

Coatex

Saint-gobain Glass France

(cnbm) Bengbu Design Research Institute for Glass Industry Co. Ltd

Marc Maurer

Mathieu Skrzypczak

Holger Spiegel

Joe Wenk

Christian Jacquemet

Patrick A C Gane

Philippe Bugnon

Catherine Jean Ridgway

George Saunders

Thomas Schmölzer

Wolfgang Kreuger

Robert Pirker

Michael Dalton

Aaro Salonen

Hans-Werner Kuster

Guenther Schall

Walter Schreiber

Thomas Ruch

Thomas Eichenberger

Karl-Josef Ollfisch

Volker Probst

Lothar Schmidt

André Fuchs

Stefan Ziegler

Leonhard Feiler

Ariane Weissler

Thomas Schlotterbach

Jürgen Beyrich

Ursula Luterbacher

Laura De Miguel

Thomas Raimann

Alain Cremaschi

Christoph Krebs

Carole Baubet

Max Hügin

Sebastien Hervieux

Ariane Blanchard

Ulrich Veith

Wolfgang Höpfl

Bruno Inderbitzin

Gerhard Giger

Ralf Bauer

Céline Vairon

Sascha Gysin

Luis Pedroso

Jan Grünert

Niklaus Raetzo

Paolo Balliello

Hermann Calwer

Lalit Sharma

Javier Camargo

Francine Karl

Gaëlle Mohler

Iñigo Sesma Pardo

Martin Melcher

Laure Dupuy-Naulet

The present invention is directed to a process for producing precipitated calcium carbonate with improved resistance to structural breakdown, wherein the milk of lime is carbonated in the presence of at least one gas other than carbon dioxide, or the carbonation is carried out in the presence of a static gas bubble comminution unit as well as to precipitated calcium carbonate obtained by such a process.

Precipitated calcium carbonate with improved resistance to structural breakdown

The present invention relates to a process for producing an aqueous suspension of precipitated calcium carbonate, an aqueous suspension of precipitated calcium carbonate and a precipitated calcium carbonate obtained by the process, a product comprising the aqueous suspension of precipitated calcium carbonate or the precipitated calcium carbonate as well as its use.

High solids precipitated calcium carbonate with copolymeric additive

The present invention relates to a process for the preparation of precipitated calcium carbonate allowing for a more sustainable and cost-efficient use of milk of lime. The obtainable products show good optical properties as well as fine particle size distributions.

Process for the production of precipitated calcium carbonate

The present invention relates to a process for producing an aqueous suspension of precipitated calcium carbonate, an aqueous suspension of precipitated calcium carbonate and a precipitated calcium carbonate obtained by the process, a process comprising the precipitated calcium carbonate and its use.

High solids precipitated calcium carbonate with cationic additive

The present invention provides a process for preparing a precipitated calcium carbonate product comprising the steps of: (a) preparing an aqueous suspension of precipitated calcium carbonate seeds by carbonating a suspension of Ca(OH)in the presence of 0.005 to 0.030 moles of Sr, in the form of Sr(OH), per mole of Ca(OH), (b) dewatering and dispersing the precipitated calcium carbonate seeds prepared in step (a) to obtain an aqueous suspension of precipitated calcium carbonate seeds having a dof less than or equal to 0.1 to 0.3 &#x3bc;m and a BET specific surface area of 10 to 30 m/g, and (c) forming an aqueous suspension of a precipitated calcium carbonate product by carbonating a slurry of Ca(OH)in the presence of 0.5 to 5% by dry weight of the precipitated calcium carbonate seeds obtained in step (b), wherein the precipitated calcium carbonate seeds have a dthat is less than the dof the precipitated calcium carbonate product and the precipitated calcium carbonate seeds have an aragonitic polymorph content greater than or equal to the precipitated calcium carbonate product obtained in step (c) characterized in that the dewatering of step (b) is carried out by the use of a tube press.

Process for obtaining precipitated calcium carbonate

The present invention is directed to a process for producing an aqueous suspension of precipitated calcium carbonate, wherein a milk of lime is prepared by mixing water, a calcium oxide containing material, at least one water-soluble polymer having a molecular weight Min the range from 200 to 6500 g/mol, and at least one slaking additive, and subsequently, the milk of lime is carbonated to form an aqueous suspension of precipitated calcium carbonate.

Production of PCC

The present invention provides a process for preparing a precipitated calcium carbonate product. The process comprises the steps of preparing slaking quick lime to obtain slaked lime; and subjecting the slaked lime, without agitation, without prior cooling in a heat exchanger, and in the absence of any additives, to carbonation with carbon dioxide gas to produce PCC. The newly prepared product develops better performance thanks to improved resistance during processing.

Process for preparing scalenohedral precipitated calcium carbonate

The present invention provides a process for preparing a precipitated calcium carbonate product. The process comprises the steps of preparing slaking quick time to obtain slaked lime; and subjecting the slaked lime, without agitation, without prior cooling in a heat exchanger, and in the absence of any additives, to carbonation with carbon dioxide as to produce PCC. The newly prepared product develops better performance thanks to improved resistance during processing.

The present invention relates to a process for the production of precipitated calcium carbonate, comprising the following steps: a) providing a reaction vessel containing an aqueous phase at an initial temperature; b) injecting a carbon dioxide generating compound into the aqueous phase until the pH of the aqueous phase is in the range of around 5 to around 7; and c) subsequently adding a calcium hydroxide slurry at an initial temperature to the reaction vessel while continuing the injection of the carbon dioxide generating compound, in order to obtain an aqueous slurry of the precipitated calcium carbonate. The addition rate of the calcium hydroxide slurry to the reaction vessel in step c) is such that an average electrical conductivity of the reaction contents in the reaction vessel during the reaction is in a range of 100 to 6,000 &#x3bc;S/cm.

Process for the production of precipitated calcium carbonate, precipitated calcium carbonate and uses thereof

The present invention relates to a process for the production of precipitated calcium carbonate, comprising the following steps: a) providing a reaction vessel containing an aqueous phase at an initial temperature; b) injecting a carbon dioxide generating compound into the aqueous phase until the pH of the aqueous phase is in the range of around 5 to around 7; and c) subsequently adding a calcium hydroxide slurry at an initial temperature to the reaction vessel while continuing the injection of the carbon dioxide generating compound, in order to obtain an aqueous slurry of the precipitated calcium carbonate. The addition rate of the calcium hydroxide slurry to the reaction vessel in step c) is such that an average electrical conductivity of the reaction contents in the reaction vessel during the reaction is in a range of 100 to 6 000 &#x3bc;S/cm.

Pigment compositions containing organic pigments with an outstanding migration-free property and an excellent rheology at high concentration, and derivatives thereof containing heterocyclic substituents. The pigment compositions contains (a) carbon black or an organic pigment containing a chromophore Qof the following formula, wherein Zand Zare O or N&#x2014;, C&#xb7; is a carbon atom with an electron in a p orbital, and n is an integer from 1 to 4; and (b) a compound containing a chromophore of the following formula (II), wherein Qis an m-valent residue of carbon black or of the chromophore Q; Gis preferably and R, R, R, R, R, R, and Rare preferably all H; m is an integer from 1 to 4. The pigment compositions can be used as rheology modifiers, preferably for pigmented coating compositions.

Surface-modified pigment compositions

A process for preparing a black colorant, preferably a black pigment, characterized in that a compound of the Formula (I) is reacted with a compound of the Formula (II) in a molar ratio of 1:2, in the presence of a catalyst which in water at 25&#xb0; C. has a pK&#x2266;4.5. For the definition of Rto R, refer to the description; preferably all are H. Likewise claimed are new crystal polymorphs obtainable by this process, and preferably single-phase mixed crystals. Also claimed are synergistic compositions. These compositions exhibit increased light stability in plastics stabilized with basic light stabilizers when they are pigmented with colorants of the invention rather than with known black pigments such as carbon black. The specification also relates, furthermore, to the use of the black colorants of the invention for coloring paints, printing inks and plastics in the mass, and to mulch film, instrument panels, woven fabrics, garden furniture items or elements for the construction industry that are pigmented with said colorants. 

Organic black pigments and their preparation

The present invention relates to a photochromic ink, the process for its preparation which is based on a spiropyran powder obtainable by melting, cooling and crushing, and to a new form of a spiropyran obtainable thereby. Said process to prepare a photochromic ink comprises the steps of a) heating and melting the spiropyran at a temperature below 250 C, b) cooling the melt to obtain a solidified spiropyran, c) crushing the solidified spiropyran to obtain a powder, d) optionally adding the powder to a binder providing the basis for the photochromic ink.

Preparation of a photochromic ink

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Village-Neuf, France

Marc Maurer