1. 48
While paint colour is an important
consideration for paint chemists
and design professionals, paint application
“feel” is key for those doing the painting.
Paint producers understand that the ease
or difficulty of rolling out the paint can
form a lasting impression on consumers
and strongly influence their perceptions of
product quality.
Paint application feel describes how it feels
to roll paint onto a surface. Typically, a
trained evaluator relies on experience to
characterize subjective impressions of a
paint rollout.
Despite the experience of the evaluators,
tests evaluating paint application feel have
been limited in accuracy and reproducibility.
And, because they rely on the evaluators’
judgement, they also can be subjective. To
objectively quantify aspects of paint feel,
Ashland scientists invented a device called
the Application Reader Technology™, or
ART device. The patent-pending ART
device consists of an infrared camera and a
force transducer incorporated between the
extension pole and the roller. It is portable
and can be used on any substrate, so Ashland
can assist manufacturers on site.
The ART of paint
The ART device objectively measures the
parameters that comprise paint application
feel. Unlike subjective evaluation techniques,
the ART device generates and records
quantitative spatial and force data in real
time during a paint rollout. The data
enables formulators to better understand
differences in paint formulations and to
tailor formulations to specific customer
preferences for paint feel. To determine an
objective measure of paint feel, technicians
first roll paint in several directions onto a
smooth wall. The ART device captures the
details of each paint stroke, speed of roller
movement, the work of rolling and the
normal and shear forces generated during
the rollout process. The weight of the paint
applied, painting time and distance are also
recorded.
Using these measurements and in-house
developed software, the ART device
calculates the total work of rolling, which
is expressed in W, the general designation
for work, expressed as J, for Joules; average
speed of rolling, normalized work of rolling;
and average painting force.
These factors reflect how the paint feel
affects how one paints. Changes in paint
formulation also change the rollout
process. By recording spatial and force
data generated during application, the
ART device identifies the changes resulting
from paint formulation differences, and
provides information and insight into
INNOVATION COATINGS
THE ART OF INNOVATION:
Application Reader Technology (ART) device quantifies paint
feel, helps manufacturers understand consumer preferences for
architectural paints.
BY K ABRAHAM VAYNBERG
Chemical Today Magazine | July 2016

2. 49
consumer preferences. The parameters of
paint application feel also serve as a baseline
to help coatings manufacturers maintain
consistency in their formulations.
Proving the ART device
Ashland scientists recently completed
a study using the ART device, in which
11 participants tested 16 commercially
available architectural paints. Half the
paints were geared for contractors, half for
do-it-yourselfers (DIY).
To perform the study, the participants
painted on drywall divided into four 7.5
ft x10 ft sections. Using 9 in (inch) rollers,
they painted each section with a single
paint. At the end of each paint application,
the participants filled out an evaluation
form. They agreed or disagreed to varying
degrees to statements about such aspects of
their painting experience as ease of transfer
from roller to wall, roller pickup, reworking,
quality and personal preference.
The ART device digitally recorded the
painting process, recording the position of
the roller as a function of time, along with the
forces exerted during the painting process.
The collected data was used to calculate dips
of the roller to load paint; paint applied (by
weight, measured by scale), roller strokes,
distance rolled, painting time, roller velocity,
average pressing force and effort.
This study also sought to determine the
paint perception attributes that most impact
overall preference. As expected, quality and
personal preference were the most highly
correlated, followed by reworking and wet
film appearance. Roller pick-up showed a
strong correlation with personal preference,
but the lowest correlation among the
parameters.
Paint characterizations and
correlations
The 16 paints were characterized according
to KU, ICI and Brookfield viscosities,
sag, leveling and open time. There were
no differences in KU viscosities between
contractor and DIY paints. ICI viscosity,
leveling and open time were higher in DIY
formulations than in the contractor paints.
Applied paint properties, such as leveling or
ICI viscosity, are common parameters for
formulating paints. So, Ashland researchers
looked at how these parameters correlate
with consumer preference. They didn’t
find many positive correlations. The data
from correlations between the average
personal preference and various applied
paint properties showed that only open
time correlated positively with personal
preference. Open time measures how long
a paint remains usable in an open can, and
thus fluid enough to allow the painter to fix
imperfections during painting. It is possible
that because DIY paints have longer open
times and were preferred by the participants
over contractor paints that the correlation
was circumstantial.
The data showed a weak positive correlation
between personal preference and ICI
viscosities, suggesting that higher ICI
measurements positively affect consumer
preference. Further, the data showed
only weak statistical correlations between
personal preference and rheological
characteristics of the paints.
Personal preference vs. ART device
data
Unlike applied paint characteristics and
rheology data, ART device data showed
stronger statistical correlations with
personal preference. The data showed
a strong negative correlation between
personal preference and the total number
of dips and length rolled. The negative
correlation indicates the fewer roller dips
into the paint required to cover the test wall
and the shorter the distance rolled, the more
likely a consumer will like the paint.
The number of strokes, painting time, effort
and average velocity all showed significant
negative correlations with personal
preference. The correlations indicate
consumers like fewer strokes, shorter
painting time and less effort. And when they
like a paint, they may paint slower.
Summing up
Paint rheology and applied paint
characteristics each produced only weak
correlations with personal preference, and
therefore are not independent indicators of
consumer preference. The ART device, by
contrast, produced a number of statistically
significant and strong correlations between
ART device-measurable parameters and
personal preference. The strong correlations
validated the ability of the ART device
to predict consumer preference. Paint
manufacturers can use data generated by
Ashland’s ART device to predict which
paints consumers are most likely to prefer.
What’s more, they can use ART device data
to help adjust paint properties to respond to
consumer preferences.
As Ashland’s study demonstrated, paints
that require the least number of dips per
given substrate size, the least distance to roll,
the fewest strokes, the shortest time to paint
with the slowest velocity and the least effort
will most likely be preferred by end users.
And for the architectural coatings market:
the painters in Ashland’s research preferred
the DIY paints over the professional grades
geared for contractors.
Chemical Today Magazine | July 2016
Ashland Drives Innovation with More Novel
Technologies That Enable Better Paint Formulation
In addition to the ART device, Ashland is developing
several new tools to help manufacturers quantify
coating additives performance, evaluate and improve
ingredient choices, streamline production processes
and formulations, and more efficiently develop new
products for market.
“Our new technologies are helping paint producers
take validation to the next level,” said Prachur
Bhargava, Ashland global marketing manager,
coating specialties. “Our customers get consistent
and quantifiable results so they can make more
informed, fact-based decisions and choose raw
materials with confidence.”
Robust and precise measurement systems are
critical for assessment of paint performance, new
product development and benchmarking formulations
against competitive products, said Bhargava. The
paint industry, though, has long relied on qualitative
and subjective evaluation and measurement to
improve product quality, whether it be related to
surface characteristics, paint feel (as described in the
main article), application or stability. Ashland’s new
technologies, Bhargava said, generate quantifiable
and reproducible data to help formulators more
precisely characterize paint properties and to improve
their formulations.
Ashland uses the LumiSizer™, a software-controlled
optically assisted centrifuge, to accelerate stability
assessment of emulsions, liquid-liquid and solid-liquid
dispersion type foam control additives, and complex
polymer-based formulations such as nonionic
synthetic associative thickeners. This accelerated
stability test accurately reflects and measures the
long-term stability of the additives in a much shorter
time frame. “The LumiSizer is a good predictive tool
to determine long-term stability,” said Bhargava.
Digital Optical Imaging with a high-magnification
digital microscope enables scientists to analyze
foam and surface defects in wet and dry films.
Using digital optical imaging, scientists can
identify hydroxyethylcellulose (HEC) and titanium
dioxide (TiO2) grit, roller spatter, dirt and surface
defects. Digital optical imaging yields quantitative
measurements that eliminate subjectivity and improve
differentiation between test paints.
Rollerpatternplaysacriticalroleincoatingappearance
and the visual perception of a paint’s hiding ability.
Current evaluation methods are qualitative, and thus
subjective. 3-D surface profilometry is based on an
axial chromatism technique. Software quantifies
various surface roughness parameters and correlates
them with roller pattern.
Finally, Ashland has developed a new rheology-
based method to measure open time and generate
reproducible results.Atribology attachment measures
torque as the paint dries. The time of the torque jump
is a measure of open time.
“We are establishing these evaluation methodologies
and technologies at our global Centres of Excellence
to serve our customers worldwide,” said Hilbert
Esselbrugge, global technical director, coatings
and construction. “Further, we and our customers
cooperate and share development ideas on a global
basis.”
Author
K Abraham Vaynberg is a Research
Scientist at Ashland Specialty Ingredients,
Ashland Inc, Wilmington, Delaware, US.