Process for preparing high ortho novolac resins

Claim 1

In a process for the production of phenol-aldehyde novolac resins of the class which is characterized by having a preponderance of ortho/ortho methylene bridges and which is prepared by an acid aqueous reaction mixture containing a material selected from the group consisting of phenol and metaalkylphenols in molar excess with a source of formaldehyde, conducting said reacting in the presence of a catalyst comprising: (A) a divalent electropositive metal compound selected from the group consisting of oxides, hydroxides and organic acid salts selected from the group consisting of formates, lactates, acetates and benzoates or mixtures thereof wherein the improvement comprises conducting said reacting with said catalyst in combination with (B) a divalent electropositive metal salt selected from the group consisting of sulfonates and fluoroborates or (C) acids selected from the group consisting of sulfonic and fluoroboric and mixtures thereof, said reacting being carried out under aqueous reflux conditions, with a phenol to formaldehyde molar ratio of about 1.20:1 to 2.0:1, said ortho/ortho methylene bridges being present in an amount of 75 to 100%.