Technical Information. High Performance Fillers in UV- curing PUR / polyester-acrylate parquet lacquers. High Performance Fillers

Transcription

1 Technical Information High Performance Fillers in UV- curing PUR / polyester-acrylate parquet lacquers High Performance Fillers

2 Introduction: The usage of micronized fillers in UV curing parquet lacquers is not common due to lack of transparency. Nevertheless there is the tendency, to use fillers more and more to increase scratch resistance and for cost reduction reasons. Nano additives are able to increase scratch resistance but the usage cannot be recommended in terms of economic efficiency. A formulation for transparent, micro-fillers on the basis of urethan/ester-acrylat has been developed. A characterization regarding optical and applicable properties as well as different methods of scratch resistance tests were made. The following trials have been carried out with nepheline syenite, quartz, fused silica and white fused alumina in order to test whether these fillers fullfill the specification regarding transparency, applicability and scratch resistance. Quarzwerke MINEX nephelin syenite Quarzwerke SEPASIL EK white fused alumina Quarzwerke SEPASIL silica flours Quarzwerke AMOSIL fused silica <8184> 05/07 2 Technical Information

3 Formulation and Tests The formulation is based on a 100% system of PUR-polyester-acrylate (QW-H4). Due to 0,5% Degussa Aerosil R972 and 0,4% BYK ATU 100 sedimentation is prevented. After a long term storing there is a slight sedimentation of the filler systems, which can be stirred up easily. All micronized fillers were used with wt. 15 % Formulation QW-H4 Laromer LR ,5 LaromerUA 19 T 28,7 DPGDA 20,1 Daracur ,8 BYK ATU 100 0,4 Aerosil R972 0,5 Quarzwerke Filler 15,0 Total 100,00 Firstly the fluid components had been mixed. After that Aerosil and Quarzwerke fillers were disperged 10 minutes with 22 m/sec. Every preparation showed a tendency to frothing. Therefore the finished samples were put into a dark climatic exposure test cabinet (20 C) until processing. Overview of the applied Quarzwerke Fillers Quarzwerke Filler Mineral Surface- Treatment d 50 * [µm] d 10 * [µm] MINEX 4 nepheline syenite none 7,6 10,4 TREMINEX PST nepheline syenite yes 7,6 10,4 MINEX 7 nepheline syenite none 4,0 12,3 TREMINEX PST nepheline syenite yes 4,0 12,3 MINEX 10 nepheline syenite none 2,7 5,2 TREMINEX PST nepheline syenite yes 2,7 5,2 SEPASIL EK 360 white fused corundum none 21,8 31,5 SEPASIL EK 360 PST white fused corundum yes 21,8 31,5 SEPASIL EK 500 white fused corundum none 12,4 24,6 SEPASIL EK 500 PST white fused corundum yes 12,4 24,6 SEPASIL QM 12 quartz none 40,0 65,0 SEPASIL QM 12 PST quartz yes 40,0 65,0 AMOSIL 520 fused silica none 17,7 53,2 AMOSIL 520 PST fused silica yes 17,7 53,2 * CILAS Lasergranulometrie, SEPASIL EK - Sedigraph 5100 <8184> 05/07 3 Technical Information

4 Application / Measurement: Fabrication of test specimens With a clearance applicator of 50 µm (AMOSIL 520 and SEPASIL QM 12 coating knife of 120 µm) films were applied by hand onto BYK opacity charts. With a coating knife of 240 µm the coating was applied onto black plastic panels and aluminium sheet metal. After 2 minutes curing was effected by Hg sand blasting. Test parameters Evaluation of distribution and surface Visual evaluation of the distribution and the surface took place. Evaluation of grindability The evaluation of grindability took place during the slight sanding of the base coat with dry corundum sanding paper 600. Brightness on black (transparency), gloss and haze For the valuation of the gloss the checking device of Byk-Gardner micro-tri gloss was used. The indicator Datacolor-Microflash with gloss-trap was used for brightness on black (transparency). Scratchability The Erichsen scrub resistance tester was used in order to check scratchability of the coatings on black plastic panels. Different steel-wool pades (fine 0) were used. Impact: 150 double stroke The surfaces after impact were evaluated by a) delta L (fading over black) and b) delta gloss (60 ). The samples had been cleaned with ethyl alcohol and fleece before and after impact <8184> 05/07 4 Technical Information

5 Evaluation of Distribution and Surface All formulations H 4 can be classified as faultless regarding flow, leveling and filming. The smooth surfaces of the H 4 formulations including fillers showed no disruption, only bubbles here and there due to the preparation. Evaluation of the Grindability There were no differences in the grindability as all samples showed the same good grindability. Fading over Black (transparency) and Gloss Formulation with Fading over Black L Delta Gloss 60 Delta L (Filled product semi-finished product) Semi-finished product 9,2 88,2 0,0 QW-H 4 (without filler) MINEX 4 12,4 68,6 3,2 TREMINEX PST 12,4 65,2 3,2 MINEX 7 13,1 66,9 3,9 TREMINEX PST 12,3 70,2 3,1 MINEX 10 13,1 68,2 3,9 TREMINEX PST 12,6 72,1 3,4 SEPASIL EK ,8 59,8 4,6 SEPASIL EK 360 PST 13,2 61,1 4,0 SEPASIL EK ,4 69,8 4,2 SEPASIL EK 500 PST 13,1 72,6 3,9 SEPASIL QM 12 11,5 71,0 2,3 SEPASIL QM 12 PST 11,7 68,0 2,5 AMOSIL ,3 64,3 3,1 AMOSIL 520 PST 12,7 62,4 3,5 The transparency of the system depends on the mineral, the grain size and the surface-treatment. The minerals nephelin syenite, quartz and fused silica with wt. 15 % are advantageous regarding the transparency compared to white fused alumina. The volume of quartz in the formulation is even higher (1,5 times) as the volume of white fused alumina taking into account the difference in density. This underlines again the excellent transparency of nephelin syenite (density 2,6 g/cm3), quartz (density 2,65 g/cm3) and fused silica (density 2,2 g/cm3) compared to white fused alumina (density 4,0 g/cm3). It is also evident that the surface treatment of nephelin syenite and white fused alumina is advantageous regarding the transparency (fading over black) compared to non-treated material. The gloss of the semi-finished product can be lowered by 16 to 29 points depending on filler, grain size and surface-treatment. <8184> 05/07 5 Technical Information

6 Scratchability Formulation with fading delta L (after - before Loss of gloss 60 (before - after) Loss of gloss 60 ((before-after) / before) [%] Semi-finished product 0,0 1,1 1,3 QW-H 4 (without filler) MINEX 4 0,0 0,0 0,0 TREMINEX PST 0,0-0,4-0,6 MINEX 7-0,2-2,3-3,2 TREMINEX PST 0,2-0,5-0,7 MINEX 10 0,2-1,2-1,7 TREMINEX PST 0,0 0,6 0,8 SEPASIL EK 360 0,3-0,4-0,5 SEPASIL EK 360 PST 0,0-1,1-1,4 SEPASIL EK 500 0,1-0,6-0,8 SEPASIL EK 500 PST 0,1-0,2-0,2 SEPASIL QM 12 0,1 3,7 4,8 SEPASIL QM 12 PST 0,0 0,6 0,7 AMOSIL 520 0,0 0,0 0,0 AMOSIL 520 PST 0,0-0,8-1,2 After mechanical load with steel-wool (fine 0) the semi-finished product shows a slight loss of gloss. The semi-finished product QW-H 4 is already a formulation with a very hard surface and marginal scratchability. All filled systems except the untreated SEPASIL QM 12 show no loss of gloss or significant fading. The systems with MINEX 7 and SEPASIL EK 360 PST show a slight polishing aspect. <8184> 05/07 6 Technical Information

7 Abstract: An appealing formulation for industrial wood protection laquers based on a 100% PUR/polyesteracrylate system was successfully developped. Quarzwerke fillers are applicable (wt. 15 %) in 100% PUR/polyester acrylate lacquers without loss of transparency. Dependend on the mineral, the grain size and the surface treatment a slight matting effect was noticed The workability and the optical characteristics (flow, leveling, surface and grindability) are excellent. The scratchability could be improved by using fillers. A considerable cost reduction could be achieved by using Quarzwerke fillers in the formulation without disadvantages in optical or technical properties. The values listed in this application technology report have been determined and presented to the best of our knowledge. However, we request your understanding that we assume no liability for the results in individual cases nor for the suitability or completeness of our recommendations and cannot be held responsible, if the protective rights of any third parties are impaired. We are at your disposal for further consultation. <8184> 05/07 7 Technical Information