Rheovis CR2 Acrylic polymer Ciba Rheology Modifier/ Thickener >> Associative >> Acrylic/Acrylic copolymer (ASE/ HMASE) Coatings >> Waterborne *HQHUDO RHEOVIS CR2, RHEOVIS CR and RHEOVIS CRX are derivatives of a family of highly effective rheological control additives for water-borne inks and water-borne coating systems. &KHPLFDO 1DWXUH RHEOVIS CR2, RHEOVIS CR and RHEOVIS CRX belong to a family of products which are based on similar acrylic polymer technology with side groups designed to provide an associate thickening mechanism. RHEOVIS CR2, RHEOVIS CR and RHEOVIS CRX are ideal rheological control agents for a wide range of water-borne inks and water-borne coatings. They are most effective over a pH range 7.5-10. The choice between RHEOVIS CR2, RHEOVIS CR or RHEOVIS CRX is dictated by the properties required. RHEOVIS CR2 has been designed to give a more Newtonian rheology. It provides optimum flow and levelling properties for semi-gloss and high-build coatings. (Ciba also offers RHEOVIS PU10 and RHEOVIS PU20, which are products allowing formulations with almost ideal Newtonian rheological profile.) RHEOVIS CR provides an improved thickening effect at low shear rates compared with RHEOVIS CR2. It is recommended for use in matt and semi-gloss coatings. RHEOVIS CRX is the most efficient thickening additive leading to a more thixotropic system. It is often used in coating systems designed for spray applications. The practical use in conventional coatings might be limited to applications where flow and levelling are less critical. In cases where even higher degree of thixotropic behaviour are required then combinations with a complementary additive such as e.g. VISCALEX HV30 is recommended. Typical rheological properties of a paint formulation equipped with the rheological control additives are given in the following graphs. (concentration adjusted to result in comparable curves The three grades RHEOVIS CR2, RHEOVIS CR and RHEOVIS CRX are chemically compatible with each other allowing formulation of blends in any ratio. In a given formulation the products may be combined as to reach the optimum overall performance. Since RHEOVIS CR2, RHEOVIS CR and RHEOVIS CRX are synthetically derived product they are less susceptible to microbiological attack than derivatives of cellulose. Consequently the paint formulator can substantially reduce the level of biocide leading to a broader area of application. Incorporation of RHEOVIS CR2, RHEOVIS CR and RHEOVIS CRX Rheological control additives with associated thickening mechanism should preferably be added at the final stage of manufacturing of the ink or coating – as opposed to addition to the pigment grinding stage - since destabilisation can occur at high shear stress. The liquid form of RHEOVIS CR2, RHEOVIS CR or RHEOVIS CRX makes this post- addition comfortable. As a positive side effect, the post-addition offers the flexibility in viscosity adjustment from batch to batch. After addition, the pH is adjusted with alkali, ammonia or other bases to achieve the full and stable viscosity. Use of volatile agents improves the water resistance properties of the dry film. The pH of the system during manufacturing of the coating should always be kept higher than 7.5 to prevent precipitation and consequent destabilisation of the formulation. In certain cases it may be advisable to dilute and pre-gel with alkali before addition. Recommended dilution factor is 1 part of additive and 5 parts of water. The amount of RHEOVIS CR2, RHEOVIS CR or RHEOVIS CRX required for optimum performance should be determined in trials covering a concentration range. Derivative of a family of highly effective rheological control additives for water-borne coating systems. Belongs to a family of products which are based on similar acrylic polymer technology with side groups designed to provide an associate thickening mechanism. Most effective over a pH range 7.5-10. Designed to give a more Newtonian rheology. Provides optimum flow and levelling properties for semi-gloss and high-build coatings. Less susceptible to microbiological attack than derivatives of cellulose. Consequently the paint formulator can substantially reduce the level of biocide leading to a broader area of application. Recommended usage level: 1.0-3.5% based on total formulation. Should preferably be added at the final stage of manufacturing of the coating – as opposed to addition to the pigment grinding stage - since destabilisation can occur at high shear stress. The liquid form makes this post-addition comfortable. As a positive side effect, the post-addition offers the flexibility in viscosity adjustment from batch to batch. After addition, the pH is adjusted with alkali, ammonia or other bases to achieve the full and stable viscosity. Use of volatile agents improves the water resistance properties of the dry film. The pH of the system during manufacturing of the coating should always be kept higher than 7.5 to prevent precipitation and consequent destabilisation of the formulation. In certain cases it may be advisable to dilute and pre-gel with alkali before addition. Recommended dilution factor is 1 part of additive and 5 parts of water.