Exploiting the Synergy of Fluorine and Silicone for Stain Resistant and Easy-Clean Coatings.

Transcription

1 Exploiting the Synergy of luorine and Silicone for Stain Resistant and Easy-Clean Coatings. Dr. Peter Hupfield, Dow Corning Ltd., United Kingdom Mr. Eiji Kitaura, Dow Corning Toray Ltd., Japan Dr. Tetsuya Masutani, Daikin Industries Ltd., Japan Mr. Masaru Nagato, Daikin Industries Ltd., Japan

2 Advantages - Reduced maintenance costs - Retention of natural appearance of the substrate - Improved weatherability and chemical resistance - Protection of historical architecture

3 luoropolymer Melting point ( o C) Solvent Solubility abrication temperature range ( o C) Reactive PTE 327 Poor No PA Poor No ETE Poor No PVD Moderate No TE Copolymer -- Excellent Room Temperature Yes High melting point High temperature processing Poor solvent solubility Architectural coatings Aircraft coatings Cookware

4 The Unique Properties of luoropolymers Molecular Characteristics - High C- C bond strength - Low dielectric constant - Low Refractive index - Weak intermolecular forces - Small polarizability Physico-chemical Properties Heat resistance Chemical resistance lame retardency Weatherability Excellent dielectric properties Self lubricity Non stick properties Water and oil repellency Applications - Release agents - Lubricants - Textile oil and water repellents - Architectural coatings - Aerospace coatings - Bakeware coatings - Chemical resistant elastomers - Cosmetics - Electronics

5 C C H C H H C Y OH C C H C H H C Z (TEC) Weather resistance Dirt Removability ilm Curing Temperature Room Temperature. High Temperature (~ 130 o C) Cross-linkable Adhesion Crosslinker Type Isocyanate Blocked Isocyanate, Melamine Transparency Solvent solubility Compatibility with resins Compatibility with additives

6 Coating Xylene Marker Dirty motor Mustard Red wine Iodine Coffee Carbon Blue Marker Red oil Water-based Dry wipe EtOH wipe TEC Isocyanate K Acrylic Isocyanate Stains applied to surface for 24 hours - Removal by wiping with a dry cloth - 5 rating is no surface staining - 1 rating is severe surface staining TEC displays poor resistance to solvent based marker

7 PTE Coating TEC Coating EtOH Dry Wipe Dry Wipe

8 The Unique Properties of Silicones Molecular Characteristics - Highly open, flexible and mobile siloxane backbone -Si -O -Si -O -Si -O - - High bond strength 435 kjmol -1 Si-O (cf. 350 kjmol -1 C-C) Physico-chemical Properties High Compressibility Low Surface tension Spreading and wetting Low surface energy Low Pour Points High Gas Permeability Thermal Stability UV Resistance Reactive functionality Excellent weatherability Applications - Release agents - Antifoams - Lubricants - Textile softeners - Coating additives - Slip modifiers - Cosmetics - Hydrophobic

9 luoro Resin OH COOH Release Agent CH 3 CH 3 CH 3 -(SiO) n -(SiO) m -CH 3 UV, Stain Stain, Adhesive agent R-X CH 3 ROS X ilm Cross-linker NCO NCO NCO Adhesion promoter OCN-R-Si(OCH 3 ) 3 Substrate:Stone, Metal, plastic etc Si(OCH 3 ) 3

10 TE CO-POLYMER (TEC) TEC + NROS TEC + ROS Dry Wipe Dry Wipe Dry Wipe Siloxane Type % Siloxane Contact angle (θ) (w/w) Water n-hexadecane ROS NROS NROS ROS NROS NROS

11 Surface analysis of hybrid coating Effect of Curing (ESCA) M A S S % Si% % 0.0 Non Hardener Add Hardner Non Si Evidence for silicone surface segregation

12 Surface analysis of hybrid coating front and back side(esca) M A S S % front side back side Si Siloxane concentration differential in coating

13 Surface Composition and Ease of Marker Removal Mass % Color difference ( E) Si Effect of ROS Siloxane surface saturation occurs at low levels Ease of marker removal related to siloxane surface content

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15 Coating Xylene Marker Xylene Marker Lacquer Red Urethane Iodine Coffee Carbon Red Black Spray Wine Sealant Water Beading Stain Beading Stain Stain Stain Stain Stain Stain Stain TEC Isocyanate TEC+ROS K Acrylic Isocyanate Key beading rating: 1 = no beading on the surface and 5 = excellent surface beading Excellent performance across a broad range of staining agents

16 Marker removability for ROS Relationship between viscosity and functional equivalent on marker removal

17 Coating washed with ROS soluble solvent

18 Solvent resistance (ESCA) Control Solvent wiped Si% % ROS is reacted into the fluororesin network

19 Solvent based marker Motor oil Water based ink Lipstick Untreated Treated

20 Stone Wiped Leather Wall Covering

21 General Coating Characteristics Items Method Results Gloss Pencil Hardness lexibility 2Φ,180 Pass Weather test Gloss retention(%) 84 (lorida exposure) after 10 years Chemical 10%H2SO4 Pass Resistance 10%HCl Pass (Appearance) 10%CH3COOH Pass 10%NaOH Pass Solvent Resistance Xylene 100 double rub Pass Water Resistance 50 C,10days No Change (Appearance) 100 C,8hours No Change

22 Summary Stain Resistant and Easy Clean Coatings Hybrid technology demonstrates excellent stain resistance and easy-clean properties Chemical resistance is not affected by presence of silicone Excellent flexibility, durability, weatherability and thermal stability Primer systems available for a wide range of substrates Room temperature curable HAP s and VOC compliant formulations available Spray or paint application Easy two part formulation Coating thickness of 5 to 10 microns typically Protection for a wide range of substrates

23 Please visit us at the European Coating Show in Nuremberg April 26th-28th 2005 Hall 1, stand number 121.