Process for preparing diallyl phthalate latex

A process for preparing a diallyl phthalate latex which comprises using in proportions of a total of 30 - 100 weight parts of monomer and a total of 0.3 - 10.0 weight parts of an anionic surfactant derived from a nonionic surfactant to a total of 100 weight parts of water, and (I) carrying out an emulsion polymerization using an emulsion polymerization system containing a mixture of

• a. water in an amount of 50 - 70 weight % of the total amount of water to be used,
• b. monomer in an amount of 10 - 20 weight % of the total amount of monomer to be used, said monomer being selected from the group consisting of a diallyl phthalate monomer and a diallyl phthalate-containing monomeric mixture wherein at least one member is selected from the group consisting of alkyl acrylate having 1-8 carbon atoms, alkyl methacrylate having 1-8 carbon atoms or a mixture thereof contained in a mole ratio to diallyl phthalate of not more than 3:1, and
• c. said surfactant in an amount of 10 - 20 weight % of the total amount of surfactant to be used;
• and
• Ii. adding at one time the entire amount of a radical catalyst;
• and then
• Iii. at a period after the degree of polymerization has reached at least 50 weight % and before completion of the polymerization, continuing the emulsion polymerization reaction while adding an additional emulsion polymerization system containing the following components and without said radical catalyst:
• a. water remaining of the total amount to be used,
• b. monomer remaining of the total amount to be used, and
• c. said surfactant remaining of the total amount to be used.