Breakthrough voltage varies non-linearly with thickness, or in other words, breakthrough field strength is not a constant, especially at very small distances like with foils. It increases as thickness decreases. Therefore the BF listed in the Foil Table may differ from the one listed in the Solid Table. Additionally, in the Foil Table is noted at which thickness the BF was measured.
Material | BF | SR | VR | e50 | e800 | e1M | d50 | d800 | d1M |
plastics | |||||||||
*ABS | 40 | -- | -- | 2.4-5 | -- | 2.4-3.8 | 30-80 | -- | 20-150 |
Celluloseacetate (CA) | 20-40 | 10e11 | 10e11-10e13 | -- | 4-7 | 4.3-4.8 | -- | 100-230 | -- |
Polyethylen (PE) | 40-60 | >10e14 | 10e16 | 2.3 | 2.3 | 2.3 | 2-10 | 2-10 | 2-10 |
*LDPE | 37 | -- | -- | 2.29 | -- | 2.28 | 1.5 | -- | 0.8 |
*HDPE | -- | -- | -- | 2.35 | -- | 2.34 | 2.4 | -- | 2.0 |
*Polypropylen (PP) | 24 | -- | -- | 2.27 | -- | 2.25 | 4.0 | -- | 5.0 |
Polyamide (PA) | 25 | 4*10e11 | >10e8 | >4 | >4 | >3.5 | >200 | >200 | >300 |
*PA-6 (Nylon-6) | 40 | -- | -- | 3.8 | -- | 3.4 | 100 | -- | 300 |
*PA-66 (Nylon-66) | 60 | -- | -- | 8 | -- | 4 | 1400 | -- | 800 |
Polyisobutylen | 23 | -- | 10e15 | -- | 2.3 | -- | -- | 4 | -- |
*PC (Lexan) | 38 | -- | -- | 3.0 | -- | 2.9 | 7 | -- | 100 |
*PET (Mylar) | 42 | -- | -- | 4.0 | -- | 4.0 | 20 | -- | 200 |
*PI (?) | 56 | -- | -- | 3.5 | -- | 3.4 | 20 | -- | 50 |
Polymethylmethacrylate (PMMA, Plexiglas, Perspex) |
40 | -- | 10e15 | 4 | 3.5 | 3 | 550 | 500 | -- |
*PMMA | 14 | -- | -- | 3.3-3.9 | -- | 2.2-3.2 | 400-600 | -- | 40-400 |
*POM | 40 | -- | -- | 3.7 | -- | 3.7 | 50 | -- | 50 |
Polystyrene (PS) pure | 50-55 | >10e14 | 10e15-10e17 | 2.5-2.55 | 2.5-2.55 | 2.5-2.55 | 3 | 2 | 3 |
Polystyrene (PS) mod. | 40-50 | >10e14 | >10e14 | 2.5-3.1 | 2.5-2.8 | 2.5-2.8 | 3-100 | 2-100 | 3-100 |
*PS | 20-30 | -- | -- | 2.5 | -- | 2.5 | 1-4 | -- | 0.5-4 |
Polytetrafluoroethen (PTFE, Teflon) |
20-35 | -- | >10e16 | 2.0 | 2.0 | 2.0 | 2 | 2 | 2 |
*PTFE | 48 | -- | -- | 2.1 | -- | 2.1 | 2 | -- | 2 |
Polychlorotrifluoroethen (PCTFE, Hostaflon) |
25-40 | 10e13 | 10e18 | 2.4 | 2.3 | 2.1-2.3 | 200 | 250 | 80 |
*PCTFE | 55 | -- | -- | 2.3-2.8 | -- | 2.3-2.5 | 10 | -- | 200 |
Polyurethane (PUR) | 20 | 10e12-10e13 | 10e13-10e15 | -- | 3.6-4.7 | 3.3-3.9 | -- | 140-550 | 300-460 |
*PUR-linear | >30 | -- | -- | 5.8 | -- | 4.0 | 1200 | -- | 700 |
*PUR-thermoset | 24 | -- | -- | 3.6 | -- | 3.4 | 500 | -- | 500 |
*PUR-thermoplas. | 30 | -- | -- | 6.6 | -- | 5.6 | 300 | -- | 600 |
Polyvinylacetal (PVAC) | 15-20 | -- | 10e11-10e14 | 3.6-3.7 | -- | 3.0 | 70 | -- | 200 |
Polyvinylcarbazol | 50 | -- | 10e16 | 3.0 | 3.0 | 3.0 | -- | 4 | 4 |
Polyvinylchloride (PVC) | 40-100 | -- | 10e15 | 3.4 | 3.4 | 3.1 | 200 | 180 | 150 |
*PVC-plasticized | 27 | -- | -- | 4-8 | -- | 4-5 | 800 | -- | 1200 |
Rubbers | |||||||||
Hard rubber (natural) |
15-40 | -- | -- | 3.2-4 | -- | 2.5-3.5 | 30-150 | 50-150 | -- |
Soft rubber (natural) |
15-50 | -- | -- | 3.5-5 | -- | -- | 20-800 | -- | -- |
Silicone rubber | 20-30 | -- | -- | 2.5-3.2 | 2.5-3.2 | -- | 4-25 | 3-10 | 20-50 |
cast resins etc. | |||||||||
Epoxy resin (EP) | 25-45 | -- | 10e15-10e17 | 3.5-3.9 | -- | 3.6 | 35-90 | -- | 150-200 |
Bitumen | 20-40 | -- | 10e15 | -- | -- | -- | -- | -- | -- |
Erdwachs (Ceresin) | 25-30 | 10e15 | 10e15-10e17 | 2.2 | -- | 3-7 | 2 | 0.5 | -- |
Synth. Wachs (Nibren-Wachs) |
15-30 | -- | 10e14-10e15 | 4-5 | -- | -- | 1-2 | -- | -- |
Polyester cast-resin (UP) | 25 | 10e12-10e14 | 10e13-10e15 | -- | 3.5-5 | 3.4-4.8 | -- | 80-300 | 120-400 |
Schellack | 10-15 | -- | 10e15-10e16 | -- | 3-4 | -- | -- | -- | 100-400 |
Material | Frequency (Hz): | 10e2 | 10e3 | 10e4 | 10e5 | 10e6 | 10e7 | 10e8 | VR | |
Good mineral oil | epsilon | 2.16 | 2.16 | 2.16 | 2.16 | 2.16 | 2.16 | 2.16 | 20°C: 5-100 |
60°C: 5-100 |
tg delta *10e4 | 0.8 | 0.8 | 0.4 | <3 | <3 | 3 | 10 | |||
Good synth. oil | epsilon | 2.22 | 2.22 | 2.22 | 2.22 | 2.22 | 2.22 | 2.20 | 20°C: 50-100 |
60°C: 5-10 |
tg delta *10e4 | 4 | 1 | 1 | <5 | <5 | 8 | 48 | |||
Hydriertes Terphenyl (HB 40) |
epsilon | 2.59 | 2.59 | 2.59 | 2.59 | 2.58 | 2.57 | 2.54 | 20°C: >50 |
60°C:
>1 |
tg delta *10e4 | 1.3 | 0.4 | 0.4 | <5 | 13 | 76 | 155 | |||
Chloriertes Biphenyl (Clophen A 50) |
epsilon | 5.05 | 5.05 | 5.05 | 5.05 | 4.30 | 2.90 | 2.75 | 20°C: 2 |
60°C: 0.2 |
tg delta *10e4 | 2 | 3.5 | 30 | 550 | 2040 | 1050 | 170 | |||
Hexachlorbutadien (Tripen) |
epsilon | 2.55 | 2.55 | 2.55 | 2.55 | 2.55 | 2.55 | 2.55 | 20°C: 22 |
60°C: 4.7 |
tg delta *10e4 | 3 | 1.5 | 1 | 1 | 1 | 2 | 16 | |||
Silicone Oil | epsilon | 2.76 | 2.76 | 2.76 | 2.76 | 2.76 | 2.76 | 2.76 | 20°C: 100 |
100°C: 100 |
tg delta *10e4 | 0.8 | 0.8 | 0.6 | 0.8 | 1 | 3 | 8 |
Material | Frequency (Hz): | 50 | 10e2 | 10e3 | 10e4 | 10e5 | 10e6 | 10e7 | 10e8 | BF | VR |
Polyethylen (PE) |
epsilon | 2.25 | 2.25 | 2.25 | 2.25 | 2.25 | 2.25 | 2.25 | 2.25 | 80 (0.1mm) |
>10e15 |
tg delta *10e14 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | |||
Polystyrene (PS, Styroflex) |
epsilon | 2.55 | 2.55 | 2.55 | 2.55 | 2.55 | 2.55 | 2.55 | 2.55 | 100 (0.1mm) |
>10e15 |
tg delta *10e14 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | |||
Polyvinylchloride (PVC) |
epsilon | 3.3 | 3.18 | 3.10 | 3.02 | 2.96 | 2.88 | 2.87 | 2.85 | 95 (0.06mm) |
>10e14 |
tg delta *10e14 | 130 | 130 | 185 | 225 | 210 | 160 | 115 | 81 | |||
Polytetrafluoroethylen (PTFE, Teflon) |
epsilon | 2.1 | 2.1 | 2.1 | 2.1 | 2.1 | 2.1 | 2.1 | 2.1 | 80 (0.07mm) |
>10e15 |
tg delta *10e14 | <5 | <5 | <3 | <3 | 2 | 2 | 2 | 2 | |||
Polychlorotrifluoroethylen (PCTFE, Hostaflon) |
epsilon | 2.72 | 2.72 | 2.63 | 2.53 | 2.46 | 2.42 | 2.35 | 2.30 | 100 (0.1mm) |
>10e15 |
tg delta *10e14 | 200 | 210 | 270 | 235 | 135 | 82 | 70 | 60 | |||
Cellulosetriacetat | epsilon | 3.8 | 3.82 | 3.77 | 3.76 | 3.53 | 3.42 | 3.30 | 3.22 | 100 (0.1mm) |
>10e11 |
tg delta *10e14 | 100 | 95 | 150 | 200 | 230 | 230 | 210 | 210 | |||
Hydratcellulose (Zellophan) |
epsilon | 4 | - | - | - | - | - | - | - | 40 (0.1mm) |
10e8-10e10 |
tg delta *10e14 | 3000 | - | - | - | - | - | - | - | |||
Polyterephtalsäureglykol- ester (Mylar) |
epsilon | 3.5 | - | 3.4 | 3.4 | 3.3 | - | - | - | 100 (0.03mm) |
>10e15 |
tg delta *10e14 | 24 | - | 55 | 180 | 160 | - | - | - | |||
Paper, dry (4 layers) |
epsilon | 1.7-2.3 | - | - | - | - | - | - | - | 7.5 | >10e14 |
tg delta *10e14 | 2.5 | - | - | - | - | - | - | - | |||
Paper, oil soaked (4 layers) |
epsilon | 3.5-4 | - | - | - | - | - | - | - | 58 | >10e14 |
tg delta *10e14 | 30 | - | - | - | - | - | - | - | |||
Paper, clophen soaked (4 layers) |
epsilon | 5.4 | - | - | - | - | - | - | - | 60 | >10e14 |
tg delta *10e14 | 40 | - | - | - | - | - | - | - |