Durable antimicrobial coating
based on silver
ag+care®
Silver
+
CCVD
Antimicrobial coating
for glass, ceramic,
enamel, stainless steel
(combustion chemical
vapor deposition)
Silver
Silver
+
CCVD
Antimicrobial
coating
Widespread use of silver compounds
• Medicine
• Dressing
• Desinfectant
• Cosmetics
• Food packaging
• Clothings…
Effectiveness of
silver
• Efficient against many kinds of bacteria, fungi, algae, and
even viruses
• No toxicity to humans
Mode of action: multiple mechanism
• Inactivating oxygen-transporting enzymes
• Chemical reacting with thiol groups of the protein
• Locking the cell membrane
Choice of silver compound
Silver salts
Elemental silver
H2O
Ag+
Silver compound is
responsible for
Concentration of Ag+
determines
• Colour
• Efficiency
• Concentration of Ag+
• Toxicity
• Rate of release of
Ag+
• Colouring
Silver
nanoparticles
Advantages of silver nanoparticles
Ag+
Ag+
Ag+
• Diameter < 25 nm
Ag+
• High specific surface
Ag+
Ag+
• Extremely small quantity of silver
Ag+Ag+ Ag+
A
g
Ag+
Ag+
Ag+
Ag+
Ag+
Ag+Ag+
• Controlled generation of Ag+
• Reservoir of silver in the core Low concentration of silver
Long lasting antimicrobial
effect
CCVD
Silver
+
CCVD
(combustion
chemical vapor
deposition)
Antimicrobial
coating
CCVD
Antimicrobial
coating with CCVD
Gas burner
Silicon compound
Silver compound
Silver
Particle
SiOx agglomerates
Silica/silver
layer
flame
Substrate
CCVD – flow chart
SiOx / Ag layer
CCVD
Technical data:
Speed: 3-5 m/min
1 step production
Antimicrobial coating
Silver
+
CCVD
Antimicrobial coating
ag+care®
R2
R3
O2
Si OR
flam
1
R4
e
O2
Ag-particle
flam
e
SiO2 + H2O + CO2
Ag-particle
Layer thickness: < 60 nm
substrate
SiO
2
Ag-particle
Surface structure
Silica / silver layer
Silica layer
µm
µm
40
20
0
µm
nm
No difference in AFM (atomic force
microscopy)
µm
Optical property - Transmission
%T
nm
Optical properties – L*a*b*
Cromaticity coordinate
glass
uncoated
L*
a*
b*
96.1
-0.8 (± 0.1)
-0.1 (± 0.1)
glass coated
with ag+care
95.5
-0.9 (± 0.1)
0.1 (± 0.1)
No colour change
Antimicrobial test
Test organism:
Escherichia coli
Staphylococcus aureus
Storage conditions: 35°C, 24h
Calculation:
%reduction = (T0-T24,Pr) / T0 x 100
log reduction = log (T24,Ref / T24,Pr)
T0 = Germ number/sample immediately after inocolation
T24,Pr = Germ number/sample after 24h incubation on the sample
T24, Ref = Germ number/sample after 24h incubation on the reference
Antimicrobial test
Test organsism: Escherichia
coli
Floatglass
uncoated
Floatglass
coated with
ag+care®
Antimicrobial effect
Test for antimicrobial effectiveness
Substrate: floatglass
According to JIS Z 2801:
antimicrobial efficacy: log. reduction >
2
Coating:
ag+care®
% reduction
log.
reduction
standard
deviation
Escherichia coli
> 99.99
> 5.61
0.48
staphylococus
aureus
> 99.99
> 5.21
0.54
Antimicrobial effect
Test for antimicrobial effectiveness
According to JIS Z 2801
Substrate:
floatglass
coating: ag+care®
log.
Reductio
n
Test
Test conditions
abrasion test
25.000 cycles with sponge in
water
leaching test
1 week in water
2.5
alkaline detergent ("Mr. Proper");
dilution 1:10 pH: 9,8; 24h at RT
2.5
acid detergent (Frosch")
dilution 1:10; pH 2,7; 24h at RT
3.5
chemical resistance test
3
conclusion
Silver
+
CCVD
Antimicrobial coating
• High antimicrobial impact
• Long lasting effect
• No coloring
• High mechanical stability
• Chemical resistance against detergents
• Easy to apply
• Low costs