Neuburg Siliceous Earth in UV-curable Coatings

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1 VM-3/ / Authorship: Siegfried Heckl Hubert Oggermüller Approval: May 2008 VM / Dr. Alexander Risch Neuburg Siliceous Earth in UV-curable Coatings HOFFMANN MINERAL GmbH P. O. Box D Neuburg (Donau) Phone ( ) 53-0 Fax ( ) Internet: info@hoffmann-mineral.com

2 Summary produced excellent results in all tests performed with it. Systems filled with have low abrasion and very high brightness. Discoloration is low and the transparency of the varnish is excellent. also has a very little tendency towards sedimentation. That means that is the optimum filler for UV-cured parquet varnishes. Its competitors, clay, talc and mica have definite disadvantages, both in terms of transparency as well as abrasion. However, to improve sanding, an additional usage of small amounts of talc is recommended for primers. In comparison with the competitors abrasion is lower with AKTISIL EM and AKTISIL VM 56 but discoloration of the varnish system is increased. That means that these AKTISIL types are t suitable for lighter colored woods. The untreated types of Neuburg Siliceous Earth, SILLITIN V 85 and SILLIKOLLOID P 87, results in higher abrasion levels compared to the AKTISIL types, and are therefore t suitable. Advantages of AKTISIL in UV-cured varnish systems Very high transparency ( graying) Good price/performance ratio due to high filling capacity Easily sanded Good adhesion High resistance to scratching Very low abrasion Annual growth has been running at around 10 to 20 % with these systems since the beginning of the 90's due to the increased demand for environmental tolerability (solvent-free) and good mechanical characteristics of UV varnishes. The tests were carried out at BASF Aktiengesellschaft, Ludwigshafen. We wish to thank BASF Aktiengesellschaft for their kind support and assistance. Page 1

3 C O N T E N T 1 Basic characteristics 1.1 AKTISIL types 1.2 Application of UV-cured parquet coatings Surfacer Primer Top coat 2 Laboratory results for parquet coatings 2.1 Abrasion (Taber Abrasion Test) 2.2 Brightness of the coating 2.3 Transparency 2.4 Discoloration 2.5 Sedimentation 3 Suggested formulations: Surfacer and primer 3.1 Translucent, UV-curable surfacer with 3.2 Translucent, UV-curable surfacer with AKTISIL EM 3.3 Translucent, UV-curable primer for wood (TSCA-approved) 3.4 Translucent, UV-curable primer for wood 4 Suppliers of auxiliaries Page 2

4 1 Basic characteristics 1.1 The AKTISIL types The AKTISIL types are activated SILLITIN types, produced by modifying the surface of the raw material by a variety of special coatings. The reaction products released through silane bonding are almost completely removed during the manufacturing process. Undesirable side-effects - such as may occur when directly dosing with silane - are therefore almost completely eliminated. Storage stability is considerably improved compared to liquid silanes. AKTISIL types suitable for UV cured varnishes: Product AKTISIL EM AKTISIL VM 56 Coating epoxy silane vinyl silane methacryl silane 1.2 Application of UV-cured parquet coatings Surfacer Amount used: 50 g/m² Filler content: % Surfacer is necessary to remove any unevenness after sanding and to avoid sharp outlines (black streaking and indentation) in the individual wood elements. Surfacer also ensures that the primer cant penetrate too deeply into the wood. This prevents discoloration. High-quality silicate fillers are essential in order to improve sanding and the mechanical properties of the surfacer Primer Amount used: g/m² Filler content: % The parquet is sanded down in order to remove any unevenness in the wood and to improve adhesion after applying the surfacer. The primer is then applied mechanically by roller. Surfacer and primer mainly influence the mechanical properties (abrasion, scratch resistance, adhesion) Top coat (varnish) Film thickness: a few µm filler A filler-free varnish is applied by roller to provide a high gloss, smooth surface. Page 3

5 2 Laboratory results for parquet coatings Binder: Laromer PO 84F Filler content: 10 % Photoinitiator: Irgacure Abrasion (Taber Abrasion Test) In the Taber Abrasion Test the positive effects of the AKTISIL types were clearly demonstrated with regards to resistance to abrasion. Competitor fillers and untreated Neuburg Siliceous Earth have considerably higher abrasion levels. The unfilled system also had higher abrasion compared to systems with AKTISIL types. without filler Aktisil MAM Aktisil EM Aktisil VM 56 Sillitin V 85 Sillikolloid P 87 Abrasion (Taber Abrasion Test) Binder: Laromer PO 84 F Abrasion 1000 U, 1 kg CS.10 in mg 2.2 Brightness of the coatings,, and produced the lowest reduction in brightness compared to the varnish system without filler. Due to the darker basic material used (SILLITIN Z 86), AKTISIL EM and AKTISIL VM 56 result in lower brightness than (SILLITIN V 88). without filler Aktisil MAM Aktisil EM Aktisil VM 56 Sillitin V 85 Sillikolloid P 87 Brightness of the Coatings Binder: Laromer PO 84 F Brightness (t exposed to light) Page 4

6 2.3 Transparency In terms of varnish transparency, and SILLITIN V 85 have considerably better characteristics than competitor fillers. AKTISIL EM, AKTISIL VM 56 and SILLIKOLLOID P 87 also do t achieve the levels obtained with AKTISIL MAM and SILLITIN V 85. Aktisil MAM Aktisil EM Aktisil VM 56 Sillitin V 85 Sillikolloid P 87 Transparency Binder: Laromer PO 84 F 0 = excellent; 5 = t acceptable Discoloration and resulted in the lowest level of varnish discoloration, while other fillers produce a conspicuous effect. Discoloration of the Varnish Binder: Laromer PO 84 F 0 = ne; 1 = low; 2 = gray; 3 = conspicuous; 4 = high Aktisil MAM Aktisil EM Aktisil VM 56 Sillitin V 85 Sillikolloid P Page 5

7 2.5 Sedimentation Unlike other fillers,, AKTISIL EM and showed propensity to sediment after a 7-day storage period. AKTISIL EM AKTISIL VM 56 SILLITIN V 85 SILLIKOLLOID P 87 Sedimentation after a 1-day storage Sedimentation after a 7-day storage 3 Suggested formulations Surfacer and Primer 3.1 Translucent, UV-curable surfacer, solvent-free Suggested formulation 4054 / 11 (March 1994) BASF Aktiengesellschaft, D Ludwigshafen Laromer LR 8793 Aerosil 380 Soja-Lecithin STA conc. Darocur 1173 (1) (2) (3) (4) (5) 63,0 35,0 1,0 0,5 2,5 Consistency: paste Reactivity (40 to 60 g/m²): approx. 10 to 20 m/min 1 lamp 120 W/cm 3.2 Translucent, UV-curable surfacer, solvent-free (for darker types of wood) Suggested formulation 4054 / 9 (March 1994) BASF Aktiengesellschaft, D Ludwigshafen Laromer LR 8793 AKTISIL EM Aerosil 380 Soja-Lecithin STA conc. Darocur 1173 (1) (2) (3) (4) (5) 63,0 35,0 1,0 0,5 2,5 Consistency: paste Reactivity (40 to 60 g/m²): approx. 10 to 20 m/min 1 lamp 120 W/cm Page 6

8 3.3 Translucent, UV-curable primer for wood (TSCA-approved) highly reactive, without solvents and reactive diluents Suggested formulation 4054 / 5a E (March 1994) BASF Aktiengesellschaft, D Ludwigshafen Laromer LR 8894 X Microtalc AT 1 Irgacure 500 Reactivity: (approx. 20 g/m²): (1) (2) (6) (5) 90,0 7,5 2,5 3,0 approx. 90 to 120 sec approx. 20 m/min 1 lamp 120 W/cm 3.4 Translucent, UV-curable primer for wood, highly reactive, without solvents and reactive diluents Suggested formulation 4054 / 5 E (March 1994) BASF Aktiengesellschaft, D Ludwigshafen Laromer PO 84 F (LR 8812) Microtalc AT 1 Irgacure 500 Reactivity (approx. 20 g/m²): (1) (2) (6) (5) 90,0 7,5 2,5 3,0 approx. 90 to 120 sec approx. 20 m/min 1 lamp 120 W/cm 4 Suppliers of auxiliaries (1) BASF Aktiengesellschaft, Ludwigshafen (FRG) (2) HOFFMANN MINERAL GmbH & Co. KG, Neuburg (Donau) (FRG) (3) Degussa-Hüls, Frankfurt am Main (FRG) (4) Langer & Co., Rittershude-Ihlpohl (FRG) (5) Ciba-Geigy GmbH, Frankfurt am Main (FRG) (6) Norwegian Deutschland GmbH, Bad Soden-Salmünster (FRG) Our technical service suggestions and the information contained in this report are based on experience and are made to the best of our kwledge and belief, but must nevertheless be regarded as n-binding advice subject to guarantee. Working and employment conditions over which we have control exclude any damage claims arising from the use of our data and recommendations. Furthermore, we cant assume any responsibility for any patent infringements which might result from the use of our information. Page 7