Document 71d3xg7nr3aEbwXpgx7nb9506
Public comments on the draft European PFAS regulation
(Use for clean room air conditioning and semiconductor equipment)
Cambridge Filter Corporation
June 30, 2023 Cambridge Filter Corporation
1
Air filters for clean rooms and semiconductor equipment
Since the air taken in and circulated to semiconductor manufacturing equipment must be extremely clean, a HEPA/ULPA class filter is essential.
Impurities and foreign matter during semiconductor manufacturing may lead to defects, and if the collection efficiency is low, it will lead to a decrease in yield and poor characteristics.
Electronics and pharmaceutical manufacturing require a clean environment, and a clean room with a high-performance air filter of HEPA or better is essential.
If the PTFE membrane filter media is replaced with glass fiber filter media, the filter pressure loss (resistance) will be approximately doubled in order to ensure the collection performance. It is estimated that the energy required to circulate the same amount of air will be approximately doubled, increasing the impact on the environment. (P5, P6)
If the collection efficiency of the air filter cannot be maintained at a high level, the products manufactured in the clean room will be contaminated, leading to loss of product functions and a decrease in yield. It is required to suppress the decrease in collection efficiency during long-term use. When electret non-woven filter media is used as a substitute, HEPA or higher collection efficiency cannot be maintained from the beginning to the end of use, making it difficult to apply to clean room applications. (P7)
When glass fiber (glass fiber) filter paper is used instead of PTFE membrane filter paper, the amount of outgas emitted from the components is increased by 10 times or more. In addition, since impurities such as boron that are harmful to the manufacturing of various products are detected, the risk of defects in manufactured products due to contamination from filters increases. (P8, P9)
Cambridge Filter Corporation
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Characteristics comparison (overall)
PTFE filter is the only material that satisfies all the properties required for high-performance air filters in a well- balanced manner.
PTFE Filter Glass Filter
Cambridge Filter Corporation
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Characteristic comparison coverage area of air filters by material
High Glass Filter
Pressure Loss
PTFE Filter
Low Sub HEPA
HEPA Efficiency
ULPA
PTFE Filter Glass Filter
Efficiency HEPA
HEPA
ULPA
PTFE Filter
Low
Glass Filter
High Contaminant
Cambridge Filter Corporation
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Pressure loss comparison
Glass-HEPA has almost the same collection efficiency as PTFE-HEPA, but the pressure loss is more than doubled.
Cambridge Filter Corporation
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CO2 emissions
Filter Grade
PTFE_HEPA Glass_HEPA PTFE_ULPA Glass_ULPA
Filter Size
mm
1230X1230X65
1230X1230X65
Q(Rated flow rate) m3/min
40.0
40.0
40.0
40.0
Q(Rated flow rate) P(Pressure drop) H(Operation time)
m3/sec Pa Hr
0.67 46.0 8760.0
0.67 90.0 8760.0
0.67 71.3 8760.0
0.67 145.2 8760.0
(Airflow efficiency)
-
0.76
0.76
0.76
0.76
Power consumption
CO2 conversion/unit
(1000)
kWh/yr 353.5
691.6
547.9
1115.7
kg /yr ton/yr
175.0
342.3
271.2
552.3
175.0
342.3
271.2
552.3
Power consumption (kWh)=(QXPXH)/(X1000) 1kWh = 0.495 kgCO2 Converting power consumption to CO2 emissions based on Saitama Prefecture ordinance values.
When 1000 filters are operated for one year, the pressure loss difference is about 170 tons for HEPA
type,The ULPA type emits about 270 tons of CO2 and has a large impact on the environment.
Cambridge Filter Corporation
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Performance persistence
Static elimination method (IPA immersion)
Air Dry
Filter
IPA
evaluation
ISO16890-4 Minimum collection efficiency after static elimination is required according to the static elimination test method for ventilation air filter units.
There is no change in the collection efficiency of the glass filter and PTFE filter before and after static elimination.
Cambridge Filter Corporation
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Low impurities (Outgassing)
< Outgassing data >
Outgassing
PTFE filter
Normal Glass
Bibutyl PhthalateDBP
ND
1,100
Methyl Ethyl Ketone Oxime
ND
1,000
Methyl Isobutyl Ketone Oxime
ND
210
Fluoro Alkyl Alcohol
ND
1,240
Etc.
461
4,310
Amount of total outgassing [g/m2]
461
7,860
UNIT : g/m2
NDNot Detectable
Method : GC-MS (Heating condition 125deg.C for 1hr)
Evaluation method
Glass filters generate 10 times more outgassing than PTFE filters
CnH2n+2, MEKO
GC-MS
Cambridge Filter Corporation
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Low impurities (does not contain boron)
< Impurities Concentrations data >
UNIT:PPM
Element
B Na Mg Al K Ca Cr Fe Ni Cu Zn
PTFE filter
ND 2 ND ND 23 ND ND ND ND ND ND
Normal Glass 53 500 3.2 0.4 36 12 ND ND ND ND 0.4
Low Boron Glass 0.8 2230 49 0.8 60 234 0.1 2.5 ND 0.1 4.4
< Condition of Analisys> Sample size: 20mm X 20mm/p Method : ICP-MS
1) Soaking in pure water(80ml) 2) Keeping for 3days at room temp.
ICPMS
C, O, Ca, Na, Cl
Boron (B) is not detected from the PTFE filter, and the effect of contamination is smaller than that of the low-boron glass filter media.
Cambridge Filter Corporation
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Annual consumption (PTFE filter media)
PTFE filter media are used for particle filtration in air filters, but since they exist in fibrous form, their annual usage volume is small.
(m2) PFAS(kg)
2020 309,066
361.6
2021 549,160
642.5
2022 648,066
758.2
90g/m2PFAS1.3%
Cambridge Filter Corporation
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