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Metallic Effect Pigmentsfor Automotive Coatings
S p a r k l e S i l v e r ® P r e m i e r
S p a r k l e S i l v e r U l t r a ™
P l a t i n u m S i l v e r ™
S I L B E R L I N E®SMT
“AquaTech Solutions” For Waterborne Coatings Silberline has developed two “world class” inhibition technologies
including our SilBerCote® AQ and AquaPaste® product lines. For more information on our SilBerCote AQ and AquaPaste products or to
request a copy of our “AquaTech Solutions” brochure, contact your local Silberline sales office or visit our website at www.Silberline.com.
Silberline, the global supplier of effect pigments
for over 40 years, has been committed to the development
and supply of the highest quality aluminum effect pigments
to the automotive industry. Through our advanced
manufacturing technologies, our aluminum pigments provide
automotive stylists and coatings formulators with brighter and
more dazzling metallic effects as well as superior degradation
resistance. Because of Silberline’s reputation for supplying the
highest quality aluminum pigments, our products have for
these many years been formulated into automotive coatings
and have contributed to the elegance and overall design
impact of motor vehicles.
The aesthetic effect achieved by an automotive coating
depends in part on pigment particle size, pigment shape,
and the degree and method of polishing the flake, all
of which contribute to the coating’s brightness, sparkle
and metallic travel.
Silberline is proud to offer the following product lines to
meet your styling and performance needs: Sparkle Silver® Premier, Sparkle Silver Ultra™ and introducing our new Platinum Silver™ line.
S I L B E R L I N E®SMT
A Wide Range of Metallic Effect Pigmentsfor Automotive Coatings
Though fineness and brightness typically trend in opposite directions with aluminum pigments, Silberline designed the flakes in Sparkle Silver Premier pigments to have more uniform surfaces, smoother edges and controlled particle size distribution. This unique “Silver Dollar” technology broke the “fineness or brightness” paradigm and gave designers whiter, brighter and cleaner polychromatic effects. Silberline’s Sparkle Silver Premier grades include SSP 354, 454, 554 and 695.
Sparkle Silver Ultra grades are highly polished, extremely bright lenticular flakes, offering a smooth patina at the fine end of the spectrum and a narrow particle size distribution. SSU grades allow the formulator to create very smooth, brilliant masstones or clean, vibrant colors. Sparkle Silver Ultra pigments are designed to achieve the highest level of metallic effects and creativity and include SSU 6704, 6756, 6605 and 6555. More recent innovative additions to the Sparkle Silver Ultra line include SSU 7908, 7807, 7806 and 6656.
Platinum Silver is the newest addition to Silberline’s superior line of silver dollar type pigments offering a highly polished appearance with exceptional brightness, excellent opacity, a “high flop index,” and a more silky smooth patina. Silberline’s “new” Platinum Silver aluminum pigments provide a wide range of metallic effects from bright silver to chromatic and include PS 008, 010, 012, 014, 016 and 018.
The above graphic details the effect of median particle size and Particle Size Distribution (PSD) on the brightness and degradation resistance properties among our more sophisticated families of effect pigments. “Head on Brightness” (HOB), or amount of colorless light reflected at the near specular L*15 angle, increases not only with increasing D50 between grades in any particular family, but is also shown to increase from one family to the next, at the same median particle size, as the particle size distribution narrows.
Degradation resistant aluminum pigments provide consistent metallic appearances in automotive coatings that are subjected to the shearing forces associated with OEM recirculation systems. By carefully selecting the proper raw materials, controlling the median particle size, and narrowing the PSD, we were able to develop grades that demonstrate dramatic improvements in resistance to circulation damage. This is illustrated in the above graph by the increased slope of the trend lines for the “HOB after Circulation” values between families.
Platinum Silver™ (PS)
Sparkle Silver® Premier (SSP)
Sparkle Silver Ultra™ (SSU)
Comparison by Grade and Family
Please consult the following tables for a product that meets your requirements.
All of the information used for comparing aluminum
pigments was generated from coatings applied over metal
utilizing Bell-Bell electrostatic equipment with dual-axes
control capabilities.
I N T R O D U C I N G
SSP 695
25
20
15
10
5
0
O r g a n i z a t i o n B a s e d O n F a m i l y
D (5
0)
L* Va
lue a
t 15 d
egre
es
Grade by Family
150
135
120
105
90
75
60
45
30
15
0SSP 554
SSP 454SSP 354
PS 008PS 010
PS 012PS 014
PS 016PS 018
SSU 7908
SSU 7807
SSU 7806
SSU 6704
SSU 6756
SSU 7605
SSU 6656
SSU 6605
SSU 6555
Grade HOB HOB after Circulation
A Wide Range of Metallic Effect Pigmentsfor Automotive Coatings
Aluminum effect pigments are plate-like particles with directional light reflectance and/or scattering characteristics.
They present variation in lightness (colorless reflection) or saturation (chroma) with changes in the viewing angle.
The brightness of these effect pigments can be described as lighter, brighter, grayer and darker, all of which are related to particle size and particle size distribution. The lightness is measured by integrating the amount of colorless light reflected back from the surface of the flakes, using a reflectometer or goniospectrophotometer, and given a numeric value L* on the L*a*b* color scale.
Comparison of Grades by Brightness
Comparison of Brightness by Particle Size
When we speak of particle size, we generally mean the average (median) diameter of the flakes, expressed as the D50. For most new automotive coating applications, the D50 usually falls within the range of 8–25 microns. Generally speaking, the smaller particles yield better hiding, appearance, and improved distinctness of image (DOI). The larger particles yield higher sparkle and brightness.
SSU 6555
30
25
20
15
10
5
0
O r g a n i z a t i o n B y B r i g h t n e s s A t 1 5 D e g r e e s
D(50
)
L* V
alue
at 15
deg
rees
SSP 354PS 018
SSP 454SSU 6656
PS 016SSU 6605
SSU 7605
SSU 6756
PS 014PS 012
SSP 554SSU 6704
PS 010SSP 695
SSU 7806
SSU 7807
PS 008SSU 7908
160
140
120
100
80
60
40
20
0
Grade
30
25
20
15
10
5
0
O r g a n i z a t i o n B a s e d O n P a r t i c l e S i z e
D(50
)
L* V
alue
at 15
deg
rees
160
140
120
100
80
60
40
20
0
Grade
SSU 7908
PS 008SSU 7807
SSU 7806
PS 010SSU 6704
SSP 695PS 012
SSU 6756
SSU 7605
SSU 6656
PS 014SSU 6605
SSP 554PS 016
SSU 6555
PS 018SSP 454
SSP 354
Aluminum effect pigments are plate-like particles with directional light reflectance and/or scattering characteristics.
They present variation in lightness (colorless reflection) or saturation (chroma) with changes in the viewing angle.
Comparison by Metallic Travel and Flop Index
The above graphic ranks the products in order of greatest to least Travel and also includes the corresponding Flop Index for each grade.
Coatings containing aluminum pigments have the ability to reflect varying intensities of light with changes in observation angles. Generically speaking, the observational angles are grouped into three categories: “Face” (near specular), “Mid Specular” (or diffuse), and “Flop” (far specular) and correlate to the instrumental viewing angles on a goniospectrophotometer as follows:
Near specular - 15 or 25 degrees Mid specular - 45 degreesFar specular - 75 or 110 degrees(Instrumental angles are determined by reference to the specular angle which is 45 degrees from normal.)
Metallic travel is described as the difference in extent to which the “Face” (also synonymous with HOB) appears a bright silver chroma when compared to the darker, grey “Flop.” The mathematical expression is given by T = L*15–L*110 using absolute values in L*a*b* color space.
Another expression for the observed changes in intensity is given by the Flop Index. The Flop Index is the measurement of the change in reflectance of a metallic color as it is rotated through the range of viewing angles. A flop index of 0 indicates a solid color, while a very high flop metallic basecoat color may have a flop index of 15–17. Flop Index is mathematically defined by:
FI = 2.69 (L*15 – L*110)1.11 / (L*45)0.86
The particle size distribution (PSD) is equally as important as the average particle size. The PSD is defined as the range in particles sizes from the smallest to the largest. The PSD is usually a Gaussian curve; however, special processes may yield a narrower range or a translated distribution.
As a rule, a grade that has a broad distribution will consist of both more fine and large flakes. A grade with more “fines” will have improved opacity but will be darker on the face angles and lighter on the flop angles. A grade that has a narrower or more controlled distribution will appear brighter on the face and darker or “cleaner” on the flop angles. This clean appearance allows for better chromatic color development in tint bases.
Precisely controlled grades such as PS and SSU can be designed to have a smoother patina* or yield greater sparkle depending on median particle size.
*Patina is an attribute of aluminum pigments described as the smoothness or silkiness (fineness) of the pigment grain. It is a visually subjective comparative term that is used to express the appearance of coatings and described by expression such as coarse, grainy, medium, fine, smooth and silky.
SSU 6555
120
100
80
60
40
20
0
O r g a n i z a t i o n B y M e t a l l i c T r a v e l A n d F l o p I n d e x
Trav
el
Flop
Inde
x + D
(50)
PS 018SSP 354
SSP 454PS 016
SSU 6656
SSU 7605
SSU 6605
SSU 6756
PS 014PS 012
SSP 554SSU 6704
PS 010SSP 695
SSU 7806
SSU 7807
PS 008SSU 7908
30
25
20
15
10
5
0
Grade
Grade Travel Fl
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S I L B E R L I N E®SMT