Methylolmelamine (MM) has a 1, 3, 5-triazine ring and three amino groups which are substituted by the methylol group. Therefore, MM acts as a proton donar and a proton acceptor on the hydrogen bond formation. In this paper the hydrogen bond formations between MM's were studied by the CNDO/2 method. In the present calculation, methanol was adopted for one of MM's in order to save the memory storage of computer and computing time, because the hydroxyl group of methanol is approximately equal to the methylol group of MM in hydrogen bonding strength. With respect to the hydrogen bond between MM and methanol N atom of MM ring plays an important role in hydrogen bond with methanol more than its methylol group. The hydrogen bonding strength of N atom of MM ring is enhanced by the adjacent amino groups, but at the same time is disturbed by the nearest neighbour methylol group substituted in the amino group.
Therefore, the hydrogen bond formation between N atom of MM ring and methnol was classified as the following three cases.
(1) The two H atoms at the 4- and 6-positions of the amino groups (refer to text) are free from the methylolization.
(2) One H atom at the 4- or 6-position is free from the methylolization.
(3) The two H atoms at the 4- and 6-positions are methylolized.
In the case (1), the stable hydrogen bond formation is possible and it gives the largest hydrogen bond energy among the three cases. In the case (2), the hydrogen bond formation depends on the configuration of the methylol group and methanol to avoid the steric hindrance between them. In the case (3), the hydrogen bond formation may be difficult. The hydrogen bond energy between methylol group and methanol is approximately equal to the hydrogen bond energy of methanol dimer. This result suggests that the methylol group of MM acts in the similar manner of the hydroxyl group of methanol in the hydrogen bond formation.

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Free urea, monomethylol urea, dimethylol urea and methylene diurea in urea-formaldehyde resins (UFR) were separated by reversed phase partition chromatography.
The analyical condition were as follows : 20 μ1 of w/v % aqueous sample solution was injected to liquid chromatograph equipped with UV detector using a column packed with Hitachi Gel 3011-0 which is porous polystyrene gel with hydroxyl end group. column size; 8 mm in diameter, 10 cm in length, detective wave length; 195 nm, eluent; water, flow rate; 1 ml/min.
An elution volume of urea peak was about 4.5 min. The amount of free urea was determined from peak area correspponding to urea with a reproducibility of 2.2 % as the coefficient of variation, The precision of the present method was comparable to that by gel chromatography using column packed with Sephadex LH-20 with dimethylformamide as an eluent.
This chromatographic procedure took about 20 min.
It was found that the elution volume of monomethylol urea is larger than that of dimethylol urea and the content of dimethylol urea in UFR prepared under the condition that the molar feed ratio of formaldehyde (F) /urea (U) =2/1 is larger than that in UFR prepared that F/U=1.5/1.

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The paper reviews the recent development of UV curable resins. Emphases are placed especially on the curing characteristics and physical properties of the cured reins. They are affected strongly by the species and compositions of resin components such as oligomers, multifunctional monomers, reactive diluents, photo iniciators and other additives.

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Continuously the final 15th paper of the H. v. Euler school on “the formation of phenol-formaladehyde resins” is abstracted. The most important point of the paper is the introduction of “quinone methids chemistry” into the resol-hardening reaction. But just at the same time K. Hultzsch reported independently on the completely same idea. On the other hand K. Fries and coworkers studied thoroughly “quinone methids” from the standpoint of organic chemistry. For the history of phenolic reins it is so important and interesting to study the works of those schools that the papers of Hultzsch and Fries are also abstracted in the present review.

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The structures of carbonized compounds yielded by heat treatment of organic materials have been studied mainly by X-ray diffraction in various ways. On the other side, the development of electron microscope technology offers directly and exactly to observe microstructures of these carbonized compounds, and it becomes quite useful for study of carbonizing behaviours about organic materials.
It is keenly interested in the behaviours of carbonization about phenolformaldehyde resins because these resins have widely been utilized for practical carbonizing sources.
Therefore, it is discussed at first in this report about carbonization and graphitization of organic materials, and secondarily about structural behaviours at carbonization and graphitization which are observed at heat treatment of phenol-formaldehyde resins. Then, succeedingly it is discussed about such physical properties as shrinkage and tensile strength of carbonized compounds, or their inherent properties like residual carbon content derived from change in average molecular weight and hexamine content. Furthermore it is discussed about kinds and quantity of emitted gas under various experimental conditions of heat treatment. These results are shown in the followings with several references and literatures.

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