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AO-Oil AO-Grease

Watch lubricant is generally applied to watch movements during the manufacturing process.

As it ages, however, lubricant can cause watches to malfunction or stop entirely by gumming up, by corroding metal parts or by sticking to plastic parts.

AO-Oil・AO-Grease is a lubricant that Citizen Watch developed in-house specifically to solve these problems.


What does AO-Oil do ?

  1. 1 Inhibits corrosion of metal and plastic parts
  2. 2 Stops clogging or thickening (maintains long-lasting lubricity)
  3. 3 Inhibits viscosity dependence on temperature (enhances energy efficiency and expands operating temperature range)

What makes AO-Oil and
AO-Grease special ?

  1. 1 Long-lasting with durability of 20-plus years
  2. 2 High corrosion resistance
  3. 3 High versatility: suitable for both engineering plastics and metals
  4. 4 Grease types: paste (AO-G08) and semi-solid (AO-G09)

Used for many years in MIYOTA watch movements, AO-Oil and AO-Grease have earned the trust of our customers with their consistently high quality. They can be used not just for watch movements and parts, but also for other precision components due to their exceptional quality and performance.

AO-Oil: Technical description

Item Unit AO-2
(Low viscosity)
(Medium viscosity)
(High viscosity)
Appearance   Clear Blue Red
Density g/m 0.83 0.83 0.83
Kinematic vicosity at -30 degree mm2/sec 1,700 6,800 14,600
Kinematic vicosity at 0 degree mm2/sec 170 550 1,050
Kinematic vicosity at 20 degree mm2/sec 60 170 300
Kinematic vicosity at 40 degree mm2/sec 25 70 120
Kinematic vicosity at 80 degree mm2/sec 8 20 30
Kinematic vicosity at 100 degree mm2/sec 5.3 12 18.5
Viscosity index   More than 140 More than 170 More than 170
TAN mgKOH/g Less than 0.15 Less than 0.15 Less than 0.15
Flash point degree More than 230 More than 230 More than 230
Pour point degree Less than -40 Less than -40 Less than -40
Surface Tension mN/m 29 29 29
Vaporability wt% 0.01 0.01 0.01
Hygroscopicity wt% 0.05 0.05 0.05
Heat resistance(120 degree/96h)   No change No change No change

Operating temperature range: -40 to +80°C (Store in a cool, dark place)

AO-Grease: Technical description

Item AO-G08 AO-G09
Worked penetration 440-460 300-320
Grease types Paste Semi-solid

Operating temperature range: -40 to +80°C (Store in a cool, dark place)

Example of use

  • Cal.2035

  • Cal.82 Series