pH colour indicator for use with agricultural compounds

Abstract

This invention discloses a new class of pH indicators suitable for use in agricultural compounds. The class comprises naturally occurring substances which are extracts from grape skins, cabbage and lecithin. Safety concerns are now causing regulatory bodies to prohibit use of chemical pH indicators in compounds which are used for crops and animals. The naturally occurring compounds of this invention satisfy these concerns of the regulators and function as well as chemical indicators of the prior art.

1 . A naturally occurring pH indicator for use in a concentrate for preparing an agricultural compound which comprises an extract from grapes, cabbage or lichen.  
     
     
         2 . A concentrate comprising a mixture of a pH modifying agent and a naturally occurring pH indicator for colouring water, which concentrate can be diluted with water and added to an agricultural chemical for application to crops, soil or animals, the agricultural chemical having an activity that varies with the pH of the water and having an acceptable agricultural activity at a pH within the range of 4-6, wherein the proportions of pH modifying agent and pH indicator in the concentrate are such that when the concentrate is diluted with water and the pH of the water is modified by the pH modifying agent, the pH indicator indicates visually when the pH of the water is in the range of from about 4 to about 6.  
     
     
         3 . A concentrate as claimed in  claim 2  wherein said pH indicator is selected from the group comprising extracts of grape skins, cabbage and lecithin.  
     
     
         4 . A concentrate as claimed in  claim 3  wherein said pH indicator is an extract of grape skin.  
     
     
         5 . A concentrate as claimed in  claim 4  wherein said pH indicator is present in a concentration of about 10 to about 25%.