Method of analysing a temperature indicating paints using a marker paint

A method of analysing a temperature indicating paint using a marker paint comprising applying an irreversible temperature indicating paint to a component of a machine, applying a marker paint to the component of the machine, the irreversible temperature indicating paint having one or more changes of colour at one or more known-temperatures, these colour changes of the irreversible temperature indicating paint indicate the temperature to which different parts of the component have been subjected, the marker paint does not change colour, operating machine for a predetermined period of time such that the component of the machine reaches its operating conditions, viewing the irreversible temperature indicating temperature paint and the marker paint on the component to produce an image of the component, analysing the image of the component to determine if any debris and/or dirt has deposited on the marker paint and to determine the amount of debris and/or dirt and analysing the image of the irreversible temperature indicating paint to determine the temperature at different regions of the component taking into account the amount of any debris and/or dirt deposited onto the marker paint,

• wherein the marker paint comprises a pigment, a binder and a solvent, the pigment comprising cobalt titanium oxide, titanium nickel antimony oxide, cobalt aluminum oxide or cadmium sulphide selenium, and
• wherein the marker paint comprises 42 wt % to 52 wt % pigment, 31 wt % to 37 wt % acrylic resin and 17 wt % to 21 wt % silicone resin excluding solvent.