Additives for Coatings
Innovation in Formulation
Holiday Inn Conference Centre, Frankfurt
20-21 May, 2008
Programme
Tuesday 20 May 09.45 - 12.15
08.30 - 09.30: Registration and Coffee
09.30 - 09.45: Opening Remarks
Session 1:Technology Trends
Moderator: David Sykes, PRA
1. Progress in the Development and Evaluation of Coating Additives
Jon Graystone
PRA, UK
The development and evolution of coatings has been accelerated in the past decade by
impending legislation, including the Solvent Emissions Directive, which is now having a
real impact on the choice of coatings technology, and the constraints under which it operates.
In parallel with this are operational and economic pressures and a market drive for
innovative products. Few if any modern coatings are viable without additives, which enable
the potential of any coating formulation to be delivered, confer additional properties and
are instrumental in reducing operational problems. This review considers examples of
developments that have been necessary for additives to maintain their crucial role in the
current climate. The potential for combinatorial and service life prediction techniques,
in speeding development, is also considered.
2. The European Coating Dispersant Market
Yana Charushkina
Frost & Sullivan, UK
Coating dispersants are the speciality additives class chemicals which are applied to
coating formulations to enhance the dispersion process, stabilise pigments in coating
formulations and improve compatibility between ingredients. Dispersants significantly
reduce manufacturing costs for coating formulations and upgrade final products. The
dispersants are divided by product type into high-molecular weight dispersants, low-molecular
weight dispersants and surfactants. The dispersant range in the market is represented by
acrylics, polyurethanes, polycarboxylates, vinyl acetate esters, polyphosphates, ethoxylates,
lecitins, sulphates and fatty acid derivates. The technological developments in the market
are driven by legislation and demand towards aqueous and high-solids systems, high-performance
and high-molecular weight dispersants, environmentally-friendly compounds. The research
covers coating dispersants applied to the following three major sectors: automotive,
industrial and decorative coatings.
3. Specialty Anionic Wetting Additives for Low VOC Aqueous Coatings
Gerald Krätschmer
Troy Chemie, Germany
The development of VOC compliant, aqueous coatings has increased the need for wetting additives.
The absence of solvent has affected critical coating properties such as substrate wetting
and adhesion, surface flow and levelling, gloss and colour uniformity. The use of a
unique, anionic, low surface tension additive to improve these coating properties is featured
in this presentation. Performance of a no VOC version of the wetting additive is presented.
The presentation compares the performance of low VOC aqueous coatings with various wetting
additive chemistries.
4. Optimising Performance with Tailored Pigment Dispersing Technology
Wim Stout* & Mike Peck
Air Products, The Netherlands
The dispersion of pigments and their performance properties are critical factors for
many coatings applications, from automotive and industrial systems to decorative coatings.
Improvements in this area offer a coatings formulator options to decrease cost, improve quality,
or differentiate their product to achive competitive advantage. Dispersants play a vital
function in maximizing the performance of pigments in aqueous systems, but their
use can be difficult and time consuming to optimize due to the diversity of pigment
chemistries and grades available, as well as the competitive interactions often seen
with other functional additives. Compounding this issue is the often proprietary nature
of the dispersants themselves, limiting the ability of a formulating chemist to use
fundamental theory and forcing greater reliance on trial and error methodology. A solution
to this dilemma is the development of surface active additives which are essentially
pre-optimized for specific performance needs. Through tailoring the affinic characteristics
for maximum interaction with targeted pigment chemistries, significant reductions in
competitive behaviour can be achieved and destabilization issues such as shock in
letdown are minimized. Additional optimization of the stabilization mechanisms can yield
robust dispersion resistance to flocculation with efficient additive levels and minimal waste.
This paper will describe the methodologies employed and the results achieved in the
development of this type of additive solution.
Tuesday 20 May 13.30 - 16.30
Session 2: Wetting and Dispersing Agents
Moderator: Jon Graystone, PRA
5. New Siloxane Based Superspreaders for Excellent Substrate Wetting
Karl-Heinz Kaesler* S, Rajaraman, A. Lejeune, G. Policello, & M.Leatherman
Momentive Performance Materials
One of the major issues for coatings development and applications is the adhesion to
various substrates, particularly of water based systems. Adhesion highly depends on several
factors like wetting of the substrate, interfacial relation (surface tensions), or chemical
bonding. This paper will focus on substrate wetting and show how to control the wetting with
specific siloxane-copolymers. Trisiloxane alkoxylates are a unique class of silicone surfactants
that exhibit a very interesting phenomenon called superspreading. Low surface tension (20.7 mN/m)
and adynamic surface tension gradient setup by the unique structure of trisiloxane alkoxylates
in dilute aqueous solutions results in a greater than 100x increase in spread area as
compared to water. This has resulted in enhanced wetting (Contact angles <1°) on non-polar
substrates and flow-leveling benefits in many coatings formulations. An issue with the
trisiloxane alkoxylates was the limited hydrolytic stability outside a narrow pH
window (6.5-7.7) that has limited its acceptance in many coatings and inks formulations with
operating pH's in 8-10 range.
To address this serious pH stability issue, this presentation will introduce two new
superspreading silicone surfactants that have enhanced hydrolytic stability of pH 6-11
respective of pH 6-8 stable. Their excellent performance as wetting additives in various
coatings formulations will be discussed.
6. Surface Modification and Characterization of Nano TiO2 Particles as an Additive
in a Polyurethane Clear Coating
Dr Mojtaba Mirabedini* M. J. Zohuriaan-Mehr & M. Sabzi
Iran Polymer & Petrochemical Institute, Iran
Surface modification and characterization of nano TiO2 particles as an additive in a
polyurethane clear coating were investigated. For improvement of nano particles dispersion,
and increasing interactions between nano particles and polymer matrix, the surface of the
nano particles was modified with APS silane. Equivalent amount of APS for monolayer formation
on the nano particles surface was determined by means of elemental analysis (CHN). The grafting
of APS on the nano TiO2 particles surface was characterized with TGA and FTIR techniques.
Mechanical properties of coatings containing various amount of nano TiO2 particles, were
evaluated with DMA technique and tensile strength measurement. The light stability of coatings
with different levels of nano particle has been tested in an accelerated QUV weather-o-meter.
The results showed that surface treatment of nano TiO2 particles with APS, improves nano
particles dispersion, mechanical properties and UV protection of urethane clear coating.
7. New Polymeric Dispersant Technology for Universal Colorants
David Cartridge
Lubrizol Advanced Materials, UK
Due to legislative pressure to eliminate alkyl phenol ethoxylates from general use and
the new restrictions on the VOC content of decorative coatings, the re-formulation of
universal colorants has been a priority for specialist producers and paint manufacturers
over the last 3 -5 years. There is a continuing requirement for cost effective polymeric
dispersants that can suitably replace the traditional technology. The paper describes the
development of a new range of polymeric dispersants for this application field and the
formulating approaches that can be used to combat the common issues of paint compatibility
and tinter stability.
8. Silicone Surfactants for Aqueous Coatings
Janos Hajas
BYK-Chemie, Germany
Silicone surfactants (polyether modified oligosiloxanes) with various molecular
weight and molecular composition have been synthesized and tested for substrate wetting
properties and overall coating performance in aqueous coatings. Surface tension reduction,
leveling, intercoat adhesion, foam stabilization and recoatability have been evaluated in
comparison with classic types of substrate wetting additives ( polyether modified
polysiloxanes, fluorosurfactants, acetylene glycol derivatives). Silicone surfactants
provide a good balance of substrate wetting and leveling properties, together with a
low level of foam stabilization, and they are in many cases an environmentally friendly
alternative to fluorinated surfactants.
9.New, Fully Mineralizable Fluorosurfactants as Coating Additives
Dr Wofgang Hierse*, E. Claus, N. Fichtner, P. Kirsch, M. Kleineidam, E. Montenegro, S. Schellenberger,
M. Seidel, M. Peschka, T.P. Knepper & R.D. Wilken
Merck, Germany
Fluorinated surfactants are important additives in coating formulations, especially
as high-performing wetting and leveling agents. During the last few years, however,
the environmental behaviour of fluorosurfactants has become an issue of concern. Highly
persistent fluoroorganic residues in the environment, coupled with bioaccumulative and
toxic behaviour in some instances, have led to legal substance restrictions and an
intensive search for environmentally benign alternatives.
Our research has identified fluorinated end groups that combine verified pathways of
full biomineralization (i.e. decay to fluoride) with high surface activity. Prototype
surfactants based on these fluorinated end groups have been shown to provide strong
levelling performance in commercially relevant coatings. We believe that this discovery
could lead to non-persistent fluorosurfactant products of significant technical potential.
Conference Reception & Dinner
19.00: Reception: Sponsored by BYK-Chemie GmbH
19.30: Dinner
Wednesday 21 May 09.00 - 12.30
Session 3: Additives for Unique Performance
Moderator: Karl-Heinz Kaesler, Momentive Performance Materials
10. Relating Performance to Claims for Antimicrobial Coatings
Peter Askew
Industrial Microbiological Service (IMSL), UK
With conventional coatings equipped with antimicrobial agents, designed to protect a
paint film from spoilage in service, relating the claim to the effect seen is relatively
straight forward. Durability and performance are easily modelled and field exposure can generate
data in which the effects can be clearly observed. With coatings designed to produce hygienic
benefits, the effects are less clear and the relationship between efficacy data, claim and
demonstrable benefit can be complex and difficult to establish. This paper discusses the
manner in which realistic claims can be established and how such an approach can help with the
design of coating systems that address the control of hygiene in a number of end uses in a
realistic and credible manner. The way in which supporting data can be generated and the
manner in which field evaluations should be performed is discussed.
11. Influence of the Additives Loading on Fire Retardant Coatings
Mohd Yusof Keton*, Dirk Kruse & Barbora Deppe
Fraunhofer Institute/ WKI, Germany
Intumescent fire retardant coatings reduce the flame spread and the fire risk through the
formation of a voluminous char protective layer. WKI research focuses on the development of
intumescent fire retardant coatings capable of providing sufficient char layer with enhanced
mechanical properties by introducing specific additives without compromising the fire retardant
performance. The influence of added additives on the fire retardant performance has been
studied via lab scale fire testing. Char strength was determined according to a method
developed by WKI. It was indicated that combinations of different additives have significantly
enhanced fire retardant performance and the char strength.
12. Durability of an Anti-microbial Coating on a Hydrophobic Surface
Allen Chasteauneuf
Nano Hygiene Coatings, UK
This paper presents a demonstration of the efficacy, durability and longevity of an
actively anti-microbial coating on a hydrophobic surface. Hydrophobic surfaces are largely
non-stick when dry and are self-cleaning when wet. When augmented with an anti-microbial
additive, the combined effects produce a coating with rapid biocidal efficacy and long
lasting properties.
13. Oxime Free Anti-skinning Agents
Dr Andrew Mason
Rockwood Pigments, UK
The best know and most widely used anti-skinning agent MethylethylKetoxime (MEKO) is a
known class 3 carcinogen and as such will be in the first phase of testing in the REACH
process. Based on the results of earlier testing it is possible that MEKO will be
reclassified as class 2, which will seriously restrict its usage. New Oxime free
anti-skinning agents have been developed as effective alternatives to MEKO. Earlier
alternatives to MEKO have often shown the required anti-skinning performance but have
been unacceptable due to a negative impact on other film properties such as drying,
colour and hardness development. The latest developments overcome these problems by
balancing the requirements of anti-skinning against those of other film properties.
14 Enhancing Productivity in Coil Coatings
Carlo Testa.
Eastman, UK
Sophisticated analytical instruments are vital for pursuing research in many areas
of modern science and technology. Confocal imaging techniques provide detailed images
of coating surfaces whilst multi angled spectrophotometers are ideal for measuring colour
differences at various angles. In conjunction with each other these techniques have
enabled Eastman to differentiate between coating additives and understand the effect
that molecular weight of cellulose esters has on the level of metallic flake alignment
in coil coatings. This understanding should enable coil producers to increase production
through fewer rejects and reduce the need for re-coating whilst substantially improving
metallic flake alignment.
15. Optimising the Rheology of Waterborne Coatings: New Non-ionic Rheology Modifier
Technology for Reducing Viscosity Loss on Tinting and Improving Sag Resistance
Dr Marie Bleuzen*, Dr Daniel Saucy & Dr Barrett Bobsein
Rohm and Haas, France
Strongly tinted paints are growing in popularity world-wide. While the best overall
performance is delivered by non-ionic associative rheology modifiers, coatings thickened
this way often have excessive loss of viscosity and low sag resistance when tinted.
A new technology for such thickeners offers significant improvements in these performance
parameters.
Wednesday 21 May 13.30 - 16.30
Session 4 Functional Minerals
Moderator: Jonathan Bourne, PRA
16. Evaluation of Chromate Based and Chromium-free Polyurethane Primers for Coil
Coated Strip Building and Construction Applications
Dr Siva Bohm1*, Pete Longdon1, Hefin Dafydd1, Bernadette Gerhartz-Quirin2 and Beate Baumbach2
1 Corus UK Ltd
2 Bayer Material Science, Germany
Coil-coating systems involving the use of chromate-based pretreatments and primers are
still widely used for building and construction applications. In the future, however,
customers and/or legislation are likely to demand a switch to chromium-free alternatives.
The aim of this study was to evaluate the protective capabilities of some chromium-free
polyurethane (PU) primers that are already available commercially or that are presently
undergoing development, and to identify products that may be acceptable alternatives to
conventional chromium-based products. Different commercial chromium-free primer and Bayer
and Corus in-house development Cr-free primer pigments were evaluated. The performance
of each primer was evaluated by means of Electrochemical Impedance Spectroscopy (EIS)
and accelerated testing. EIS studies showed a clear difference between different primer
systems and water permeability. The results of EIS studies are compared and contrasted with
data generated using accelerated tests.
17 New Findings for Nanosilica Particles in UV Coatings
Marco Yann Heuer
Nanoresins, Germany
The topics covered in this paper will include:
- Improvements of the nanoparticles for uv-curing plastic clear coats
- Limitations for improvements of uv-curing plastic clear coats
- Additional benefits for nanocomposite containing UV-curing plastic clear coats
18 The Influence of Nanoadditives on Surface, Permeability and Mechanical Properties
of Self-organised Organic-inorganic Nanocomposite Coatings
Dr Milena Spirkova* Libuse Brozova, Adam Strachota, Jiri Kotek & Miroslav Slouf
Institute of Macromolecular Chemistry, Czech Republic
Transparent and colorless nanocomposite coatings featured by high degree
of self-assembly of the organic - inorganic matrix were prepared from
functionalized organosilicon precursors and oligomeric diamine or triamine.
Unmodified and chemically modified montmorillonite, bentonite, laponite or
colloidal silica was used as coating nanoadditives, differentiating in the
shape, size, and origin. The concentration of nanoparticles in coatings was
mainly units of percent. The influence of the kind and concentration of
additives on surface properties (surface roughness, surface hardness
determined from nanoindentation experiments or as the scratch resistance),
on permeability and on mechanical properties (static and dynamic mechanical
analysis) will be discussed.
19 New Concepts in Matting Agents
Dr Uwe Ferner
Grace, Germany
Silica technology is well known in the coatings industry as a base for efficient and
universal to be used matting agents. Modern industrial coatings and new applications
challenge the formulator to improve paint properties that are related to film surface or
interaction with chemicals from the environment. This requires also matting agents with
additional benefits. Furthermore a matting agent interacts with other formulation components
which raises the need to modify to avoid negative impact on film properties and processing of
the liquid paint. In this presentation new developed matting agents that fulfill these
needs are presented.
20 Organosilanes and Sol-Gel Technology for Optical Coating Applications
Dr Pierre Chevalier*& Ana Marques
Dow Corning, Belgium
Higher performance coatings with improved visual quality while being environmentally
compliant have become of prime importance in growing areas such as primers, automotive,
architectural, and industrial maintenance applications. As such, the organosilane
technology - alone or in combination with other materials as additives has proven to
be effective at improving the performance of a variety of coating systems, owing to the
unique ability of organosilane molecules to form covalent bonding between inorganic and
organic compounds along with the inherent stability and flexibility of the siloxane bond.
This paper will review the fundamentals of organosilane chemistry including sol-gel
technology and its relevance to various coating applications, focusing onto optical
properties.
16.30 End of Conference
Note: The organisers reserve the right to change papers and speakers, if necessary.