With this Lineco pH testing pen it is easy to determine if a paper or board is acidic. A simple method to distinguish between a safe (neutral or alkaline) and an acid material. Easy to use, simply draw a small line on the material you wish to test. The chlorophenol red indicator solution in the pen will turn purple on any paper with a pH of 6.8 and above. A clear or yellow colour indicates the material is probably unsuitable for conservation purposes. 

• Quick and easy test
• Turns purple on paper with pH 6.8 and above
• Unreliable results may occur on coloured or coated paper