1. Features of BLACK 700 series
- Excellent ozone crack resistance
- Excellent polar solvent (Ester and Ketone base) resistance
- Excellent chemical resistance
2. Hardness and color
- Hardness: 40・50・60・70・75・80 (JIS-A)
- Color: Black
3.Physical Data of Black 700 series
| BLACK 740 | BLACK 750 | BLACK 760 | BLACK 770 | BLACK 780 | |||
|---|---|---|---|---|---|---|---|
| Original Physical Properties | Hardness | JIS-A | 40 | 50 | 60 | 69 | 78 |
| 100% Tensile stress | MPa | 1.1 | 1.7 | 2.9 | 5.0 | 5.0 | |
| 200% Tensile stress | MPa | 2.2 | 4.1 | 6.7 | 12.0 | 9.5 | |
| 300% Tensile stress | MPa | 3.6 | 7.0 | 11.3 | 18.5 | 14.8 | |
| Tensile strength | MPa | 15.9 | 17.5 | 17.9 | 19.2 | 21.7 | |
| Elongation | % | 800 | 600 | 450 | 310 | 420 | |
| Tearing srength | N/mm | 30.6 | 27.5 | 29.6 | 25.5 | 39.8 | |
Schob impact resilience | % | 42 | 42 | 34 | 30 | 24 | |
JIS impact resilience | % | 60 | 58 | 47 | 43 | 35 | |
| Physical Properties after anging | Hardness | JIS-A | 43 | 52 | 65 | 74 | 81 |
| 100% Tensile stress | MPa | 0.9 | 1.5 | 3.3 | 5.9 | 7.2 | |
| 200% Tensile stress | MPa | 2.1 | 4.4 | 8.0 | 14.3 | 13.6 | |
| 300% Tensile stress | MPa | 4.3 | 7.4 | 13.2 | - | - | |
| Tensile strength | MPa | 15.3 | 14.3 | 16.3 | 18.1 | 19.2 | |
| Elongation | % | 730 | 500 | 370 | 240 | 290 | |
| Tearing srength | N/mm | 25.5 | 22.4 | 23.5 | 20.4 | 31.6 | |
Schob impact resilience | % | 43 | 42 | 36 | 31 | 22 | |
Abrasion resistance by Akron tester | cc | 0.378 | 0.368 | 0.196 | 0.164 | 0.101 | |
| Gravity | 1.09 | 1.1 | 1.12 | 1.14 | 1.26 | ||
| Compression set | % | 22 | 18 | 18 | 22 | 33 |
【Test method】
Physical properties were tested in accordance with JIS Standard.
Abrasion resistance by Akron tester: Load=6 lb, 1000 revolutions
Compression set: Compressibility 25% 70°C×22H
Aging condition: Temperature 100°C×48 hours
4.Chemical resistance of BLACK 700 series
| BLACK 740 | BLACK 750 | BLACK 760 | BLACK 770 | BLACK 780 | |||
|---|---|---|---|---|---|---|---|
| Chemical Test | Rubber solvent | 2Hours | 45 | 40 | 34 | 30 | 23 |
| 5Hours | 71 | 62 | 54 | 45 | 37 | ||
| 24Hours | 101 | 87 | 81 | 72 | 71 | ||
| 48Hours | 93 | 81 | 77 | 70 | 75 | ||
| 50°Cdry | -27 | -23 | -18 | -13 | -1 | ||
| MEK | 2Hours | -2 | -1 | 1 | 1 | 1 | |
| 5Hours | -2 | -1 | 1 | 2 | 2 | ||
| 24Hours | -4 | -3 | 1 | 2 | 4 | ||
| 48Hours | -6 | -5 | -1 | 3 | 5 | ||
| 50°Cdry | -14 | -12 | -8 | -5 | -2 | ||
| Ethyl acetate | 2Hours | 0 | 0 | 0 | 2 | 2 | |
| 5Hours | 0 | 0 | 2 | 3 | 4 | ||
| 24Hours | -3 | -1 | 2 | 4 | 6 | ||
| 48Hours | -5 | -3 | 2 | 5 | 7 | ||
| 50°Cdry | -15 | -12 | -9 | -5 | -1 | ||
| Toluene | 2Hours | 45 | 40 | 34 | 30 | 25 | |
| 5Hours | 72 | 63 | 55 | 48 | 42 | ||
| 24Hours | 91 | 84 | 80 | 73 | 74 | ||
| 48Hours | 95 | 77 | 75 | 70 | 76 | ||
| 50°Cdry | -30 | -25 | -20 | -15 | -3 | ||
| Ozone Test | Static Test | 1Hour | NC | NC | NC | NC | NC |
| 2Hours | NC | NC | NC | NC | NC | ||
| 4Hours | NC | NC | NC | NC | NC | ||
| 6Hours | A1 | NC | NC | NC | NC | ||
| 1Day | A1 | NC | NC | NC | NC | ||
| 2Days | A1 | NC | NC | NC | NC | ||
| Dynamic Test | 1Hour | NC | NC | NC | NC | NC | |
| 2Hours | NC | NC | NC | NC | NC | ||
| 4Hours | NC | NC | NC | NC | NC | ||
| 6Hours | A1 | NC | NC | NC | NC | ||
| 1Day | A1 | NC | NC | NC | NC | ||
| 2Days | A1 | NC | NC | NC | NC |
【Test method】
Chemical test: Sample... 1 gram cube Temperature... 20°C
Ozone Test: Ozone density... 50pphm Temperature... 40°C
Static tension rate... 20% Dynamic tension rate... 20%
【Judging standard of Ozone test】
| Number of cracks | Size and depth of cracks |
|---|---|
| A: Few | 1: Visible by tenfold magnifying lens |
| B: Many | 2: Visible by naked eyes |
| C: Countless | 3: Deep and rather big (within 1mm) |
| NC: None | 4: Deep and big (1mm-3mm) |
| e*: Crack on sides | 5: Bigger than 3mm or almost cut off |