mix liquid citric acid (50%) with the same volume of water. then neutralize under agitation vy slowly adding the sodium hydroxide solution. the neutralization reaction should be done cautiously under agitation, as the reaction is highly exothermic. add sodium xylene sulfonate and sodium silicate to the neutralized citrate solution; blend until dissolved. add the anionic surfactant, the remaining water, the fragrance, dye, and optical brightener. NOTE: the clear liquid has a pH in the range of 9-10 and a viscosity of 100-150 cps. recommended use level: 1/2 cup per full load.