The reaction of urea with aromatic aldehydes (X - CHO, X =H, Br, Cl, NO₂, OCH₃) was carried out in alcohol using potassium hydroxide as a catalyst. In the reaction of urea with aliphatic aldehydes alkylol ureas have been obtained, but in this work the reaction products were alkylethers of p-substitutedbenzylol ureas. and only in the reaction of urea with p-nitrobenzaldehyde at room temperature p-nitrobenzylol urea was obtained. The reaction path was also investigated by thin layer chromatography. From these results, it is assumed that owing to K⁺and the electron attracting nature of p-substitutedphenyl nuclei the etherification between p-substitutedbenzylol urea and alcohol used as the reaction solvent arises more easily in the reaction of urea with aromatic aldehyde than with aliphatic aldehyde.

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Non-catalytic reaction of hydroxymethylation has been studied. It has become clear that its reaction concern_ing formaldehyde may be described as a pseudo first order reaction. The effective rate constant of the reaction concerning formaldehyde (K_ef) has a simple mathematical relation to ratios of its components. At the smaller molar ratios, the effective rate constant is expressed by the following equation :
K_ef = K (n_o- K_a) (m_o -K'_a) = Knm= Kp where K-characteristic rate constant of the system
Ka, K'a-constants n_o= [L] ₀/ [A] ₀, m_o= [S] ₀/ [L] ₀, P_o= [S] ₀/ [A] ₀
A-formaldehyde
S-component, subjected to hydroxymethylation (substrate)
L-solvent
[X] ₀-initial concentration of component X
In the present work, starting from the equation (1) and applying the molar ratio method to the concentrated systems, a method for the determination of the actual concentration of formaldehyde and substrate participating in the hydroxymethylation reaction, immediately according to the data given by the study of kinetics of hydroxmethylaion reaction, has been introduced.

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First 20 papers of the K. Hultzsch school on the phenolformaldahyde resins are listed up and then 6 papers of them, related to the quinone methids theory, are abstracted. Secondly the constitutional formulae of “Resite”, developed by F. Raschig, M. Koebner, N. J. L. Megson, K. H. Meyer, H. Mark and R. Houwink, are mentioned historically. While these formulae have only methylene bridges, A. Zinke, H. v. Euler and K. Hultzsch postulated the formation of other bridges-i.e. dimethylene-ether, quinone methid, diphenyl ethaneetc. Mentioning the point aimed at the research of those three schcools, the present author sets a high value on their originality.

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The foundry technology is one of the important metal molding technology, which has been applied for various metal products, for example automobil parts, valves and iron casting pipes. The foundry mold is mainly produced by sand and its binder.
Among various kinds of inorganic and organic binder, thermosetting resin is preferably used from the viewpoints of the productivity and the easiness in sand reproduction.
Thermosetting resin for foundry use, of which the quantity reaches approximately 50 thousands tons anually in Japan, should be considered one of the important application field among thermosetting resins.
They are phenol formaldehyde formaldehyde resin, furane formaldehyde resin, polyurethane resin and other miscellaneous resins, and they are selected by the requirements of each foundry process.
They have the common characteristics in high density crosslinking net work, high heat deformation temperature and strong adhesion to sand.
The basic properties of each thermosetting resin for various foundry process are discribed in this paper.

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