SC Coating - Air purification technology powered by SmartCoat™ _V.2022.pdf

Air purification technology powered by SmartCoat™
Version 2022.01
Titanium World Technology Sdn Bhd
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Table of Contents
01 Problem Statement | The air quality problem [Pg: 3]
02 Photocatalytic production of reactive oxygen species (ROS) [Pg: 6]
Volatile organic compound (VOC) degradation by ROS [Pg: 6]
Introduction | SC Coating
03
Scientific papers on the hydroxyl radicals oxidation of Formaldehyde
[Pg: 7]
Scientific papers on Titanium Dioxide versus Formaldehyde [Pg: 7]
Conclusion [Pg: 9]
04 Controlled degradation of limonene by SC Coating [Pg: 10]
Photocatalytic removal of NOx [Pg: 10]
05 Photocatalytical removal of SOx [Pg: 11]
Oxidation of Carbon monoxide [Pg: 11]
06 Field Data for SC Coating [Pg: 12]
07 Removal of Bacteria, fungi and spores [Pg: 13]
08 SC Coating versus air purifiers [Pg: 14]
09 Conclusion | SC Coating [Pg: 16]
10 References [Pg: 17]
IN THIS DOCUMENT THE ABILITY OF SC COATING TO PURIFY AIR WILL BE SHOWN, FURTHER A COMPARISON
TO NORMAL AIR PURIFICATION BY AIR PURIFIERS WILL BE MADE.
02 | SC COATING
This document and all the information contained in it are strictly private and personal to its recipients and should not be copied, distributed or reproduced without authorization.

03 | SC COATING
PROBLEM STATEMENT
nitrogen oxides (NOx) - nitric oxide (NO) and nitrogen dioxide
(NO2)
sulfur dioxide (SO2)
Carbon monoxide (CO)
Volatile organic compound (VOC) – Formaldehyde, Benzene,
Toluene, Ethylbenzene etc.
Particulate matter – this includes all of the above
Clean air is a basic requirement of life. The quality of air inside
homes, offices, schools, day care centres, public buildings, health
care facilities or other private and public buildings where people
spend a large part of their life is an essential determinant of healthy
life and people’s well-being.
Hazardous substances emitted from buildings, construction materials
and indoor equipment or due to human activities indoors, such as
combustion of fuels for cooking or heating, lead to a broad range of
health problems and may even be fatal. Indoor exposure to air
pollutants causes very significant damage to health globally –
especially in developing countries (World Health Organization, 2010).
When looking at air quality some of the critical air pollutants are:
These can have a major effect on the health of humans. Most of
these pollutants have that in common that they all originate from the
same kind of source, which is combustion of material.
On a separate note, cleaning is essential to protecting our health in
our homes, schools and workplaces. However, household and
cleaning products - including soaps, polishes and grooming supplies -
often include harmful chemicals.
Many cleaning supplies or household products can irritate the eyes or
throat, or cause headaches and other long-term health problems,
including cancer. Some products release dangerous chemicals,
including volatile organic compounds (VOCs).
The air quality problem

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PROBLEM STATEMENT
Vehicle exhaust up to 30%
Biomass burning (including seasonal open fires, cooking, and heating) up to 20%
Industries up to 20%
Soil and road dust up to 15%
Diesel generators up to 15%
Open waste burning up to 15%
Power plants up to 5%
Outside the urban airshed up to 20%
Shampoo
Hairspray
Deodorant
Perfume
Air fresheners
Cleaning sprays
Laundry detergent
Disinfectant wipes
Hand sanitizer
Glue
Paint
Looking at Particulate matter, in this case PM2.5 from measurements in Delhi, it is shown that 90.1% of all
particulate matter is created from a sort of combustion, such as generators, waste burning or transport (S.
Guttikunda, 2016).
The sources for pollutants in Delhi have been analyzed through ambient sampling and dispersion modelling-based
studies and show the following max estimates (sum is more than 100% as all upper estimates for the source have
been used) (S. Guttikunda, 2016):
Looking at the air quality, India have set a 24 hour standard of 60 μg/m3 PM2.5 concentration, while the WHO
guidelines suggest a 24 hour standard of 25 μg/m3 PM2.5 concentration.
Looking at the data from the 9th of January until the 13th of January. The 24 hour average in Delhi was between
120-240 μg/m3 (S. Guttikunda, 2016), this is double of the Indian standard and more that 4 times the WHO
standard for the best 24 hour value measured during that period. These problems are not only seen in Delhi but, in
all major cities which have a high density of traffic.
Another rising problem has been shown to be the release of VOCs by consumer products in the Indoor
environment (B. C. McDonald, 2018). Some of the consumer products that have been Identified as releasing
VOCs are:

PROBLEM STATEMENT
These products are assessed to produce 38% of all VOC emissions for the indoor climate (B. C. McDonald, 2018).
This is a higher percentage than what gasoline and diesel cars are emitting.
Therefore, the emissions of these consumer goods and their effect on the indoor climate have to also be
considered.
It is of importance to assure that the air quality indoors is improved and the best way to do this is by purifying the
air inside the buildings, this can be achieved by the use of SC Coating as will be shown in the next sections.
05 | SC COATING

06 | SC COATING
In this section we will take a look at how SC Coating works and how it removes Volatile organic compounds, NOx,
SOx and carbon monoxide. This is shown by literature studies, experimental results and in field results.
Photocatalytic production of reactive oxygen species (ROS)
The natural degradation of biologic material and organic compounds can be dramatically accelerated by the use of
a photocatalyst such as titanium dioxide - TiO2. Upon exposure to light with energy above the TiO2 band gap (3.2
eV), energy rich electron- hole pairs are produced in the oxide structure (eq. 1). Once at the surface of the
material, such charge carriers interact with ambient oxygen and water generating highly reactive superoxide,
hydroxyl radicals and hydrogen peroxide (eq. 2-4). Hydroxyl, superoxide radicals and hydrogen peroxide are the
reactive oxygen species (ROS) ultimately responsible for the biocidal and air purification activity of SC Coating
through non-selective oxidation of biologic material and organic compounds.
TiO2 can be engineered by the addition of transition metals such as silver and copper to partially absorb light in the
visible range, opening to its use in environments lacking UV exposure (i.e. indoor). The catalyst is never consumed
during the reaction, ensuring a continuous process during the service life of the coating.
Volatile organic compound (VOC) degradation by ROS
The hydroxyl radical ∙OH is the primary oxidant responsible for the degradation of volatile organic compounds
(VOCs) into carbon dioxide and water, following the model reaction scheme below:
𝑉𝑂𝐶 + ∙𝑂𝐻 + 𝑂$ → 𝐶𝑂$ + 𝐻$𝑂 (5)
The amount of time required for a VOC to be completely oxidized to CO2 and water will depend on many factors
including illumination intensity and source, type of VOC, ventilation. Unwanted intermediate oxidation products
might be formed in the process; however, it can be expected that these oxidized by-products will also be destroyed
by the hydroxyl radicals in the same fashion as the original VOC.
The degradation of benzene, toluene, Ethylbenzene and o-Xylene by TiO2 coatings was shown by a study created
for the California Energy Commission (Berdahl, 2008). The oxidation rate of all four VOCs where shown to be
between 2.11-2.73 μmol/m2 per hour.
INTRODUCTION
SC COATING

Scientific papers on the hydroxyl radicals oxidation of Formaldehyde
Scientific papers on the hydroxyl radicals oxidation of Formaldehyde Hydroxyl radicals are one of the free radicals
generated on the surface of SC Coating, therefore it is of interest to see if they have the potential of oxidizing
formaldehyde.
A study (W.J. McElroy) investigated the effect that hydroxyl radicals have on formaldehyde in aqueous solutions.
In this experiment hydrogen peroxide (H2O2) was exposed to a photolysis to create the free radical hydroxyl
radical (OH•). After that step the formaldehyde was added to the aqueous solution. The reaction showed to form
formate, which is a product that arises from the oxidation of Formaldehyde. Figure 1 shows the formate generation
over time of an aqueous mixture of H2O2 and formaldehyde, saturared with argorn(Ar).
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INTRODUCTION
SC COATING
Figure 1: Formate concentration vs. time profile following photolysis at 253.7 nm of an Ar-saturated solution containing
1 x10-2 mol dm-3 H2O2 and 1.6x10-2 mol dm-3 formaldehyde (pH 2.2). (W.J. McElroy)
From this figure it is pretty clear to see that the formaldehyde reacts with the hydroxyl radical forming formate. The
reaction mechanism for this and the further reaction of formate will be explained in the next part of this document.
Scientific papers on Titanium Dioxide versus Formaldehyde
There have been made several studies on the effect of titanium dioxide (TiO2), together with UV induced light,
effectiveness on the removal of formaldehyde.
In a paper by S. Sun (S. Sun, 2010). it is described how they send formaldehyde and water through an air system
over a coated and illuminated area to look at the reduction of formaldehyde by TiO2. Through this experiment it
was shown that a significant increase in CO2 was measured, showing that the formaldehyde has been removed
via oxidation over the TiO2 coated surface, further different amounts of water was added through the airflow to
show the effect of humidity on the reaction. A reaction scheme was made to show the reaction steps happening
on the TiO2 Coated surface, see Figure 2.

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INTRODUCTION
SC COATING
During the photocatalytic oxidation of formaldehyde on the TiO2, the formaldehyde is adsorbed by the hydroxyl
groups on the catalyst surface via hydrogen bonding. With UV irradiation, the formaldehyde is rapidly converted to
formate species even on the pure TiO2 at mild conditions. The humidity has a positive effect on the photocatalytic
oxidation of formaldehyde.
The reason is that the introduction of water results in an accumulation of the hydroxyl radical OH• on the catalyst
surface. The hydroxyl radical OH• is an extremely powerful oxidant due to its high redox potential. As a result, the
formation rate of intermediate formate, as well as the final products CO2 and H2O is increased significantly.
In another study by J. Shie (J. Shie) Formaldehyde was used to show the potential of TiO2 surface coating to
remove potential toxic VOCs. In this study a reactors inside was coated with silver doped TiO2 and afterwards a
known volume of formaldehyde was added to the reactor, further water was added to keep the humidity at 50%.
This experiment was done with three different light sources UVA, UVC and UVLEDs. The results of the reduction
of formaldehyde can be seen in figure 3.
Figure 2: Proposed reaction scheme for the photocatalytic oxidation of formaldehyde on the pure TiO2 a superoxide
radical anion O2 as oxidant; b hydroxyl radical OH as oxidant (S.Sun, 2010)
Figure 3: Reduction of formaldehyde on TiO2 coated surface illuminated by a variety of UV
and UVLED lights. (J. Shie et al)

As seen from the figure all illuminations sources have an effect on the photocatalytical reaction of the TiO2
surface, and they all remove formaldehyde over time, reducing them to formate and further breaking them down to
CO2 and H2O, the production of CO2 over time can be seen in figure 4, further showing that the formaldehyde is
broken down into water and carbon dioxide.
09 | SC COATING
INTRODUCTION
SC COATING
Both of these studies clearly show that TiO2 has the potential of removing formaldehyde from the air. For the
effectiveness of the removal it is important that there is a sufficient light source, enough air humidity to accelerate
the process and an air flow so that the coated surface is in contact with a high volume of air over time.
Conclusion
It can be concluded that SC Coating has to potential to not only remove formaldehyde but also other VOC’s.
For the process to be effective it is however important that the conditions are good, meaning that there needs to
be a good illumination source, enough air humidity and a decent air flow, so that a high amount of volume crosses
the coating.
The reduction and removal of formaldehyde leaves behind residue water and Carbon dioxide, thus creating a
cleaner environment than before. With other VOC’s a mineral residue can also be left and thus cleaning of the
surfaces will be necessary over time as to remove these residues.
Figure 4: Conversion of formaldehyde to final product CO2 as the function of irradiation time
under dry conditions. (S. Sun et al)

Controlled degradation of limonene by SC Coating
The efficacy of SC Coating in the degradation of VOCs can be assessed with a simple setup consisting of a UV
source, a bag made of a chemically inert polymer (Tedlar), coated on the nside and filled with limonene, a
reference VOC.
The concentration of the VOC is then monitored over a defined period of time and compared with a control
reference measured in a non-coated bag. As Figure 5 shows, limonene concentration steadily drops over time,
indicating that the coating is able to degrade the model VOC.
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INTRODUCTION
SC COATING
Photocatalytic removal of NOx
NOx is the common term describing the toxic gaseous pollutants NO and NO2, produced by the reaction between
oxygen and nitrogen under high temperatures (e.g. combustion engines). In the recent decades, photocatalytic
materials such as TiO2 have been studied for the ability of degrading pollutants in air including NOx.
TiO2 is able to oxidize NOx to less harmful nitrate that can be removed by water following the mechanism
depicted in Figure 6. Maggos et al. investigated commercial TiO2 photocatalytic paint in a small chamber and
indoor car park, and found that the paint was able to remove a significant amount of both NO and NO2 from the
gas phase (T. Maggos J. B., 2000).
In another study, NOx removal was also observed from TiO2 impregnated tiles in a reaction chamber (Land,
2010). Finally, special photocatalytic cement has been developed with TiO2 to lower the NOx (S. Karapati, 2014).
Figure 5: Concentration of limonene as a function of time; when contained in a bag coated with SC Coating.
Blue Data point have been acquired in a control environment using a non-coated bag.
Surface TiO2 concentration: 7 µg/cm². Bag volume: 25L Illumination: Velleman blacklight (15W, 365nm, 850 lumen),
positioned 50cm from the center of the bag

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INTRODUCTION
SC COATING
Photocatalytical removal of SOx
SOx are a common term for sulfur oxides. The most abundant is SO2. Human emissions of SO2, because of
combustion, cause acid rain and have negative health effects on humans and nature. SO2 is also formed by
combustion of sulfur and by volcanic eruptions. SO2 is found in the air at a concentration of 1 ppb or less.
Like NOx, SO2 gas can be oxidized to sulfate salt or sulfuric acid on the surface of TiO2 based photocatalysts (J.
S. Dalton, 2002). The photocatalytic action of TiO2 products has been found to oxidize and remove SO2 from air
(P. Krishnan, 2013).
In a study by Y. Yuan et al. the simultaneous removal of NOx and SO2 has been observed. (Y. Yuan, 2012)
No found data or observations are reporting that TiO2 is able to create SOx. Sulfur has to be present in order to
make SOx and since the most sulfur present already is SOx at very low concentrations, the only thing TiO2
catalyst is able to do is to lower the concentration by oxidizing it further. TiO2 catalysis is not a combustion but
simply a speeded-up process of the cleaning that happens naturally in the air.
Oxidation of Carbon monoxide
It is known, that in the natural cycle of carbon monoxide, hydroxyl radicals play the defining role in the oxidation
from carbon monoxide to carbon dioxide. Furthermore, a newer study by Parker also shows that it is the hydroxyl
groups that are the factor in the oxidation of carbon monoxides, even at low temperatures (Parker, 2011).
A study by Debono et al. also showed that CO is being oxidized on the nano-TiO2 surface (O. Debono, 2013).
Therefore, it can be concluded that SC Coating will not produce Carbon monoxide and further it has been shown
that it has the potential to remove carbon monoxide and oxidize it to carbon dioxide instead, which is less toxic.
Figure 6: Schematic representation of the photocatalytic removal of NOx by a TiO2 coating.
Figure adapted from (J.S. Dalton, 2002)

Field Data for SC Coating
Looking at field data, SC Coating has shown to have a great effect on the indoor climate. On a whole floor of a
building, measurements where made 24 hours a day first without SC Coating for 12 days and then SC Coating
was applied to all surfaces and another 14 days of testing where done.
The test measured formaldehyde, overall VOC, PM 2.5, PM 10, CO2, humidity and temperature. In this test the
most important results will be for formaldehyde and VOC reduction. While the Data set isn’t completed yet, the first
results show a clear reduction of formaldehyde and VOC in the areas in the times from 8 and onwards, when
there is light both natural and artificial, while you see an increase in formaldehyde and VOC at night when there is
no light source. To show this the results for one day of experiments for formaldehyde and VOC will be shown in
Figure 7 and Figure 8.
12 | SC COATING
INTRODUCTION
SC COATING
Figure 7: Data points for formaldehyde 20th November 2018. Minimum 0 ppm, average 0.055 ppm.
Figure 8:Data points for overall VOC 20th November 2018. Minimum 0.14 ppm, average 0.49 ppm.

Both graphs clearly show that around 8.00 in the morning light is turned on and that SC Coating starts breaking
down formaldehydes and other VOCs, the average load stays low over the period from 8.00-20.00 after which the
concentrations of both start raising again until the next day at around 8.00 where the concentrations again drop.
These results go again for all the other days on which the experiments have been done, after SC Coating has
been applied.
Looking at the daily average for formaldehyde it was 0.138 ppm before the application of SC Coating and 0.070
after the application. The daily average for total VOC was 1.258 ppm before the application of SC Coating and
0.5236 ppm after the application. When looking at these numbers it is clear to see that SC Coating has an effect
on the indoor environment. Once can expect even better results when the surface would be exposed to
illumination all 24hours a day, while they in this experiment on average where exposed 12 hours and some days
even less.
Removal of Bacteria, fungi and spores
Titanium dioxide coating is well known to destroy bacteria, fungi and spores. This has been shown for SC Coating
by passing several European standard tests (EN test).
The list of EN test passed can be seen below:
This list includes the most common indoor bacteria and fungi as well as certain viruses.
Further, in a study (Edward J. Wolfrum, 2002) it was shown that, under comparable conditions and illumination,
99.9% of E. coli where killed in about 1 h while it took 72 h to achieve about 90% killing of A. niger spores by
titanium dioxide coating.
13 | SC COATING
INTRODUCTION
SC COATING

SC Coating versus air purifiers
When looking at the comparison between SC Coating and air purifiers one will need to look at several aspects.
For this case we have looked at some of the most used air purifiers in India which are produced by LG and
Panasonic.
First, we need to look at how air purifiers clean the air. The most commonly used air purifiers use a filter system
where air is sucked in passed through the filter and then exit out the other end. These filters will have to be
cleaned/changed every so often 6-12 months as they lose effectiveness over time. SC Coating is applied to
surfaces and remains active for at least 12 months and the coating is maintained by normal cleaning efforts.
Secondly, we have to look at filter quality. Filters are ranked after the HEPA standard which demands that the
filters must remove at least 99.97% of particles that have a size greater than 0.3 μm. HEPA filters are good at
removing larger particles from the air and trapping them inside the filter. This however also means that the filters
won’t stop all pollutants, smaller pollutants like certain bacteria and viruses can pass through the filter without
problem and microorganisms can accumulate and multiply in the filter and then get released back into the air.
Figure 9 shows the drawbacks of HEPA filters. And visualizes how larger microorganisms get stuck in the filter,
but still are able to grow and release spores to the surrounding and in this way not stopping the spread of bacterial
and viricidal infections. SC Coating on the other hand destroys microorganisms that come in contact with the
coated surface, which therefore ensures a minimal risk of bacteria and viruses spreading and growing.
14 | SC COATING
INTRODUCTION
SC COATING
Figure 9: Illustration of HEPA filters drawbacks (Do, 2017)

Thirdly, while air Purifiers are mostly quiet, they can be noise at times, with up to 60 DB (depending on the air
purifier used) and the size of the air purifier will mean that it can take up useful space from a room/area. Which
can be a disturbance for the ear. SC Coating is a coating and thus will remain unnoticed by customers.
Finally looking at the air purifiers room coverage we can see that the biggest machine can cover an area of 47.5
square meters before it begins to be ineffective. Meaning that one would need multiple air purifiers to keep large
areas covered. SC Coating on the other hand is sprayed on the surfaces and thus can cover any size of room
without problem. Further, SC Coating needs no electricity as the movement of air in the room happens naturally
through people moving in and out, ventilation and so on.
15 | SC COATING
INTRODUCTION
SC COATING

16 | SC COATING
CONCLUSION
Throughout this document it was shown that SC Coating can remove
volatile organic compounds such as formaldehyde, benzene, toluene,
ethylbenzene and o- xylene, and also reduce NOx, SOx and carbon
monoxide.
Studies in field also proved the removal of volatile organic
compounds by showing a clear reduction of formaldehyde and overall
VOC once light was activated compared to no light. Further is
showed lower average formaldehyde and overall VOC compared to
the same area without SC Coating.
It was shown that SC Coating can work as an air purifier compared to
commonly used air purifications machines and that SC Coating even
has advantages compared to commonly used air purifiers.
It was especially clear that SC Coating is a better solution when the
areas that need purification are large, as the biggest air purifier only
covered 47.5 square meters.
SC COATING

B. C. McDonald, J. A. (2018). Volatile chemical products emerging as largest petrochemical
source of urban organic emissions. Science, 760-764.
Berdahl, P. a. (2008). Evaluation of Titanium Dioxide as a Photocatalyst for Removing Air
Pollutants.
California Energy Commission, PIER Energy-Related Environmental Research Program.
CEC-500-2007-112.
Do, V. (2017, March 31). Pros and Cons of HEPA Filter Air Purifiers, Dissected. Retrieved from
molekule.com: https://molekule.com/blog/pros-cons-hepa-filter/
Edward J. Wolfrum, J. H.-C. (2002). Photocatalytic Oxidation of Bacteria, Bacterial and Fungal
Spores, and Model Biofilm Components to Carbon Dioxide on Titanium Dioxide-Coated
Surfaces. Environmental Science & Technology, 3412-3419.
J. Shie. Photodegradation kinetics of formaldehyde using light sources of UVA, UVC and
UVLED in the presence of composed silver titanium oxide photocatalyst,
J. Shie, C. Lee, C. Chiou, CT Chang, CC Chang, CY Chang; Journal of Hazardous Materials
155 (2008) 164–172
J. S. Dalton, P. A. (2002). Photocatalytic oxidation of NOx gases using TiO2: a surface
spectroscopic approach. Environmental Pollution, 120(2), 415-422.
Land, E. M. (2010). Photocatalytic degradation of NOX, VOCs, and chloramines by TiO2
impregnated surfaces. Georgia Tech. Georgia Tech Theses and Dissertations.
O. Debono, F. T. (2013). Gas phase photocatalytic oxidation of decane at ppb levels: removal
kinetics, reaction intermediates and carbon mass balance. Journal of Photochemistry and
Photobiology A: Chemistry, 17-29.
P. Krishnan, M.-H. Z. (2013). Photocatalytic degradation of SO2 using TiO2-containing silicate
as a building coating material. Construction and Building Materials, 197-202.
Parker, S. (2011). The role of hydroxyl groups in low temperature carbon monoxide oxidation.
Chemical Communications, 1988-1990.
S. Guttikunda, P. J. (2016). What’s Polluting Delhi’s Air? Retrieved from Urbanemissions.info:
http://www.urbanemissions.info/blog-pieces/whats-polluting-delhis-air/
S. Karapati, T. G. (2014). TiO2 functionalization for efficient NOx removal in photoactive
cement. Applied Surface Science, 319, 29-36.
S. Sun, J. D. (2010). hotocatalytic Oxidation of Gaseous Formaldehyde on TiO2: An In Situ
DRIFTS Study. Catal Lett, 137, 239–246.
T. Maggos, J. B. (2000). Application of photocatalytic technology for NOx removal. Applied
Physics A, 89(1), 81-84.
T. Maggos, J. B. (2007). Photocatalytic degradation of NOx gases using TiO2-containing paint:
A real scale study. Journal of Hazardous Materials, 146(31), 668-673.
W.J. McElroy. Oxidation of Formaldehyde by the Hydroxyl Radical in Aqueous Solution, W.J.
McElroy and S.J. Waygood, J. CHEM. SOC. FARADAY TRANS., 1991, 87(10), 1513-1521
World Health Organization. (2010). WHO Guidelines for Indoor Air Quality. The WHO European
Centre for Environment and Health.
Y. Yuan, J. Z. (2012). Simultaneous removal of SO2, NO and mercury using TiO2-aluminum
silicate fiber by photocatalysis. Chemical engineering journal, 21-28.
17 | SC COATING
REFERENCES

jasonkuan@smartcoat.com.my
+6019 311 1101
heng@smartcoat.com.my
+6012 283 4298
brendanwong@smartcoat.com.my
+6017 391 5321
lilian.tang@smartcoat.com.my
+6012 228 5217
18 | SC COATING
Titanium World Technology
Sdn. Bhd.

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