Satintone Specialty Extenders for Use in Coatings Applications
Satintone Specialty Extenders for Use in Coatings Applications Calcined kaolin products by BASF have become universally used in latex and solvent-based paints because of their excellent balance of properties and cost performance. BASF offers four uniquely different Satintone calcined kaolin extender pigments to the coatings industry. These four products span a range of particle sizes, oil absorptions, brightness levels, and morphologies (particle shapes) that provide various coating properties. This variety gives paint formulators added latitude to choose the extender pigment with the right combination of properties for their coating needs. This brochure features a comparison of four Satintone products and evaluates their relative performance in latex flat wall paints. The study provides formulators with a guide for selecting Satintone grades for specific formula requirements. Physical Properties All members of the Satintone family of extender pigments are similar in that they are calcined water processed fractions of platy kaolin. Water processing ensures freedom from coarse particles, and, therefore, very low screen residue levels and consistently high Hegman grinds. Calcination, a controlled heat treatment, causes dehydroxylation of the kaolin crystal and produces a very white abrasion resistant pigment particle. Calcination, more importantly, imparts changes in the particle morphology which offer enhanced optical properties to coatings. Table 1 lists the typical physical properties of the Satintone calcined kaolins in order of their average particle size. The areas in which they differ most, in addition to particle size, are oil absorption, brightness, and, in the case of Satintone OP, a lower specific gravity. They are similar in most other respects. All Satintone products are highly pulverized for good dispersion in water or solvent-borne systems and offer a minimum 5 Hegman grind and low 325 mesh residue. Figure 1 plots the typical particle size distributions of the Satintone extender pigments. Satintone 5HB is the finest particle size calcined grade. It is designed for maximum hiding. It has premium brightness and the highest oil absorption. Satintone SPECIAL is a fine particle size high brightness grade with intermediate oil absorption. In coatings, it offers a combination of high hiding and high scrub resistance. Satintone OP is a medium particle-size grade with a lower specific gravity and brightness than other Satintone grades. It also possesses a unique particle morphology which gives excellent hiding, with good sheen control and stain resistance to coatings. Satintone W is a medium particle-size grade with high brightness and the lowest oil absorption. Satintone W offers a balance of good hiding, sheen control, and scrub resistance. This combination of properties and cost-performance has made Satintone W a standard of the coatings industry. page 2 Satintone Specialty Extenders
Table 1: Satintone Calcined Kaolin Extenders for Coatings Applications. Typical Physical Properties Satintone Product Designation 5HB SPECIAL OP W Physical Form Highly Pulverized Powder Special Modifications Dehydroxylated by Controlled Heat Treatment Average Particle Size (µm) (Equivalent Spherical Diameter) 0.8 1.2 1.3 1.4 Hegman Grind, Min. 5+ 5+ 5+ 5+ Oil Absorption Rubout (D-281)** 85-95 55-65 75-85 50-60 Residue. +325 Mesh Wet Screen, % Max. 0.015 0.01 0.02 0.02 Brightness (G.E.) 90-92 90-92 86-88 90-92 ph 5-6 5-6 5-6 5-6 Refractive Index 1.62 1.62 1.62 1.62 Specific Gravity (g/cc) 2.63 2.50 2.63 2.63 Free Moisture, % Max 0.5 0.5 0.5 0.5 Bulking Value kg/ltr 2.6 2.6 2.5 2.6 Bulk Density (kg/m 3 ) Loose 210 260 260 320 Tamped 320 480 480 480 Satintone Specialty Extenders page 3
Relative Paint Performance In general, all of the Satintone products gave good hiding, scrub resistance and tint strength. These features are what make Satintone the extender pigments of choice for flat and egg-shell wall paints. However, differences between Satintone grades are apparent. The greatest differences between paints is generally poorer film integrity between 50 and 65 PVC formulations, regardless of Satintone grade used. The following summarizes the major differences between the Satintone grades for paint performance: Satintone 5HB Satintone 5HB gave the highest hiding and tint strength of all the Satintone grades, and the highest gloss and sheen. This is expected since it has by far the finest particle size distribution. On the other hand, it gave lower scrubbability and holdout, due to its high oil absorption. Satintone 5HB is ideally suited for developing extremely high hiding in both low and high PVC formulas. It is generally recommended at low levels (5%) in combination with other Satintone grades to enhance hiding. In formulations below the CPVC, Satintone 5HB gives the best TiO 2 extension, because of fine particle size spacing effects. It is used in many egg-shell and satin formulas for this reason. Satintone SPECIAL Satintone Special gave an excellent overall balance of properties with very good hiding and tint strength combined with good holdout, (especially at lower PVC) and the best scrub resistance. Sheen was higher than all but Satintone 5HB. Satintone Special is recommended for egg-shell formulas and lower PVC flats where good overall cost performance is required. Satintone OP Satintone OP gave the most interesting performance of all the grades. It has unique morphology which enhances optical properties. Consequently, it gave the second highest hiding, tint strength, and relatively low sheen. Its unique morphology also results in the best touch-up properties and very good holdout. Scrub resistance and reflectance were the lowest of all the Satintone grades. This combination of properties makes it very well suited for low cost, high dry hiding flats where high whiteness and scrub resistance are less critical. It is also used in exterior coatings, such as interior/exterior house paints, where good crack resistance, mud crack resistance, and good hiding are required. Satintone W Satintone W is the most commonly used grade and possesses an overall balance for good hiding, scrub resistance, sheen control, color and holdout properties. It is used in the broadest range of coating applications. Figure 1: Typical Particle Size Distributions Percent Finer Than 100 90 80 70 60 50 40 30 20 10 0 20 2 Equivalent Spherical Diameter in Microns Satintone 5HB Satintone Special 0.2 Satintone OP Satintone W page 4 Satintone Specialty Extenders
Figure 2: @ 38 micron 98.0 Figure 3: Kubelka-Munk spreading rate at 0.98 600 97.5 500 97.0 96.5 96.0 95.5 Opacity (spreading rate) 400 300 200 95.0 100 94.5 5HB Special OP Satintone Grades W 0 5HB Special OP Satintone Grades W 50 PVC 65 PVC 50 PVC 65 PVC Figure 4: Tint Strength (L Reflectance) Figure 5: Scrub Cycles to Failure 79 800 Tint Strength (L Reflectance) 78 77 76 75 74 73 72 71 70 69 Scrub Cycles 700 600 500 400 300 200 100 68 5HB Special OP Satintone Grades W 0 5HB Special OP Satintone Grades W 50 PVC 65 PVC 50 PVC 65 PVC Satintone Specialty Extenders page 5
Formulations and Test Methods The four Satintone products were compared for paint performance in 50 and 65 PVC latex flat wall paint formulas given in Table 2 and 3, respectively. The 50 PVC formula represents a high quality latex flat where good wet and dry hiding, good touch-up, excellent scrub resistance, and excellent holdout are required. The 65 PVC formulation is designed for low cost, high dry hiding and minimum sacrifice in other performance properties. The paint properties are summarized in Table 4 and 5. Several properties are graphically displayed in bar chart form in Figures 2-8. Table 2: 50 PVC Interior White & Light Tint Base Materials Weight % Water 11.79 KTPP 0.09 Dispersant 0.52 Wetting Agent 0.35 Biocide 0.04 Defoamer 0.09 Coalescing Aid 1.22 HEC Thickener 0.26 Propylene Glycol 1.75 Water 4.36 Mix Until Smooth & Add Flat Grade TiO 2 17.46 Calcium Carbonate. 5 µm 8.73 Satintone Calcined Kaolin 10.91 ATTAGEL 40 Thickener 0.61 Disperse at High Speed & Add Defoamer 0.09 Vinyl Acrylic Latex (55%) 26.01 2% HEC Solution 11.35 Hiding was measured using both contrast ratio and Kubelka-Munk (K-M) methods. The K-M method is considered more accurate and equalizes each formulation for film thickness and reflectance. K-M opacity is expressed in spreading rate at complete hiding (0.98 contrast ratio) per unit volume of paint. Scrubbability was measured using the shim method with silica abrasion media. Tint strength was measured using 3 oz/gallon of universal black tint. Film porosity was measured testing % ink holdout (K&N). Touch-up was compared visually by brushing a picture frame pattern over a film of the same paint applied by a roller. Table 3: 65 PVC Interior White & Light Tint Base Materials Weight % Water 19.15 Dispersant 0.21 Wetting Agent 0.26 Biocide 0.09 AMP -95 0.17 Defoamer 0.13 HEC Thickener 0.26 Propylene Glycol 2.15 Water 4.29 Mix Until Smooth & Add Flat Grade TiO 2 6.44 Calcium Carbonate, 5 µm 13.31 Satintone Calcined Kaolin 22.33 ATTAGEL 40 Thickener 0.60 Disperse at High Speed & Add Defoamer 0.13 Vinyl Acrylic Latex (55%) 17.52 2% HEC Solution 12.97 Total 100.00 Water 4.36 Total 100.00 page 6 Satintone Specialty Extenders
Table 4: Paint Performance Properties 50 PVC Latex Paint Properties 5HB SPECIAL OP W Viscosity KU 81 81 80 82 38 microns 97.6 96.1 97.1 95.9 75 microns 99.3 99.0 99.3 98.9 Kubelka-Munk spreading ft 2 /gal 474 395 423 392 rate at 0.98 CR m 2 /liter 11.63 9.69 10.38 9.62 Reflectance White 92.3 91.7 91.4 91.5 Whiteness 82.9 82.7 76.8 82.5 Yellowness 2.5 2.6 3.9 2.7 60 Gloss 2.7 2.6 2.5 2.5 85 Sheen 14.0 7.8 4.9 6.0 % Holdout, K&N Ink 52.4 62.2 61.8 64.0 Scrub Cycles to Failure 420 676 374 682 Touch-Up Good Good Good Good L Reflectance 73.8 72.3 72.7 71.9 Tint Strength a -8.3-8.3-8.4-8.3 b -25.9-27.7-26.6-27.7 Table 5: Paint Performance Properties 60 PVC Latex Paint Properties 5HB SPECIAL OP W Viscosity KU 82 79 84 79 38 microns 97.8 96.6 97.6 96.3 75 microns 99.5 99.1 99.3 98.7 Kubelka-Munk ft 2 /gal 517 391 475 351 spreading rate at 0.98 CR m 2 /liter 12.69 9.60 11.66 8.62 Reflectance White 92.2 91.6 90.7 91.3 Whiteness 79.0 76.9 68.1 76.6 Yellowness 3.6 3.9 6.2 4.0 60 Gloss 3.5 2.8 2.8 2.7 85 Sheen 27.4 13.6 7.4 10.4 % Holdout, K&N Ink 32.9 36.5 41.4 40.0 Scrub Cycles to Failure 66 100 57 85 Touch-Up Fair Fair Good Fair L Reflectance 78.0 75.1 75.5 74.0 Tint Strength a -7.7-8.1-8.4-8.3 b -20.4-24.0-21.2-24.4 Table 6: Comparison of TiO 2 Extension for Satintone Products 50 PVC Latex Paint Pigmentation (parts by weight) 5HB SPECIAL OP W* TiO 2 160 195 185 200 Satintone Products 125 125 125 125 Calcium Carbonate 130 104 111 100 Hiding (38 microns) 95.9 95.8 96.1 95.9 (75 microns) 99.0 98.8 99.0 98.9 * Control TiO 2 Extension An additional series of 50 PVC paints were prepared and tested for opacity to compare the relative cost performance of each Satintone grade as a TiO 2 extender. In this study, Satintone W was considered the control and the TiO 2 level (200 parts) was reduced to a level required to give equal contrast ratio with the other Satintone products. The calcium carbonate level was increased on a volume basis to maintain 50 PVC. The results are given in Table VI and show that Satintone 5HB, OP and Special give better TiO 2 extension than Satintone W. Satintone 5HB is particularly interesting because it required 20% less TiO 2 for equal hiding, thereby offering significantly lower formula costs. Conclusions The broad range of Satintone calcined kaolins available allows paint formulators increased latitude in optimizing cost-performance in latex or alkyd coatings. Each Satintone grade offers a different balance of paint properties, TiO 2 extension, and cost. The PVC level selected by the formulator dramatically affects film properties, in many cases more than the pigmentation. However, proper selection of pigment combinations helps modify and optimize costperformance. Satintone Specialty Extenders page 7
About BASF BASF Corporation, headquartered in Florham Park, New Jersey, is the North American affiliate of BASF SE, Ludwigshafen, Germany. BASF has more than 16,000 employees in North America, and had sales of $19.9 billion in 2011. For more information about BASF s North American operations, visit www.basf.us. BASF is the world s leading chemical company: The Chemical Company. Its portfolio ranges from chemicals, plastics, performance products and crop protection products to oil and gas. We combine economic success, social responsibility and environmental protection. Through science and innovation we enable our customers in almost all industries to meet the current and future needs of society. Our products and system solutions contribute to conserving resources, ensuring healthy food and nutrition and helping to improve the quality of life. We have summed up this contribution in our corporate purpose: We create chemistry for a sustainable future. BASF posted sales of about 73.5 billion in 2011 and had more than 111,000 employees as of the end of the year. Further information on BASF is available on the Internet at www.basf.com. BASF Corporation 100 Park Avenue Florham Park, NJ 07932 USA Contacts BASF kaolin AmericaS Charlotte Technical Center 11501 Steele Creek Road Charlotte NC 28273 USA web: www.kaolin.basf.com E-mail: kaolin@basf.com Europe, Middle East and AFRICA E-mail: kaolin-europe@basf.com ASIA AND PACIFIC E-mail: kaolin-asia@basf.com While the descriptions, designs, data and information contained herein are presented in good faith and believed to be accurate, they are provided for guidance only. Because many factors may affect processing or application/use, BASF recommends that the reader make tests to determine the suitability of a product for a particular purpose prior to use. NO WARRANTIES OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, ARE MADE RE- GARDING PRODUCTS DESCRIBED OR DESIGNS, DATA OR INFORMATION SET FORTH, OR THAT THE PRODUCTS, DESCRIPTIONS, DESIGNS, DATA OR INFORMATION MAY BE USED WITHOUT INFRINGING THE INTELLECTUAL PROPERTY RIGHTS OF OTHERS. In no case shall the descriptions, information, data or designs provided be considered a part of BASF s terms and conditions of sale. Further, the descriptions, designs, data and information furnished by BASF hereunder are given gratis and BASF assumes no obligation or liability for the descriptions, designs, data or information given or results obtained, all such being given and accepted at the reader s risk. = registered trademark of BASF Group. 2013 BASF, Florham Park, NJ 07932. All rights reserved. EU, AP