Chemical indicating composition, autoclave process indicator and method for preparing autoclave process indicator

A chemical indicating composition, comprising:

• an aqueous resin in a form of polymer emulsion or polymer dispersion, having a molecular weight of 20,000 or more and an acid value of 60 or less, the aqueous resin comprising a first aqueous resin composition having a minimum film-forming temperature of 30° C. or more and a second aqueous resin composition having a minimum film-forming temperature lower than 30° C.;
• a film-forming agent;
• a color changing composition;
• and
• water as a solvent,
• wherein, based on total weight of the chemical indicating composition,
• the solid weight percentage of the first aqueous resin composition is 10-30%,
• the solid weight percentage of the second aqueous resin composition is 0-35%,
• the weight percentage of the film-forming agent is 1-10%,
• the weight percentage of the color changing composition is 15-40%,
• the total weight percentage of the water contained in the aqueous resin and the water as a solvent is 20-70%, and
• the solid content of the aqueous resin and the color changing composition are in a weight ratio of 1:3 or greater.