Yes, this chemical is one of a family of condensed pyrophosphates that sequester calcium and keep it in solution. Another chemical often used is sodium hexametaphosphate, tradename Calgon.
There is a funny story about Calgon. The Calgon company used to market two forms of this chemical for retail customers. One was the pure chemical and there was also Calgon Bath which contained soap and a perfume. One poster complained that his developer foamed badly with use, but it did smell good.