There have been reported many synthesis methods about Methyl Vinyl Ketone (MVK).
However, the dehydration of 3-keto-butanol (1) synthesized from acetone and formaldehyde is widely used in laboratory.
It is well known that formaldehyde reacts with compounds containing activated hydrogens such as acetone.
Formaldehyde and sodium hydroxide are added from the top of the reaction column, while the rate of addition of formaldehyde and the catalyst, mol ratio of formaldehyde and acetone, and the pH value by wt% of sodium hydroxide were controled.
The excess acetone and water were removed by distillation under a reduced pressure after the gas phase reaction.
Subsequent fractionation of the residual liquid took out a fraction of bp 73-76°C at 13mmHg.
It was identified by IR spectrum, the elemental analysis and the refractive index of 3-keto-butanol (1).
MVK, dehydrated 3-keto-butanol (1) and fractionated in 80-82°C was an colorless, reactive liquid D₄²⁵ 0.8393, n_d²⁵ 1.4084. A mixture of MVK with water (vol. ratio of 85: 15) boils at an azeotropic point 75-78°C.
The MVK synthesized was identified by IR spectrum and elemental analysis, and the best yield of MVK are obtained.

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The polymerization of methyl vinyl ketone (MVK) with benzoyl peroxide (BPO) and azobisisobutyronitrile (AIBN) has been studied in various solvents such as acetone, ethyl acetate, dioxane and chloroform.
The kinetics of the polymerization are discussed.
The degassing was performed in a set of vacuum line at 10^-3mmHg and dry purified nitrogen gas passed through the monomer solution in the glass ample.
The conversion ratio for the polymerization of MVK is very low in ethyl acetate solution and high in dioxane solution.
The overall rate of the polymerization in ethyl acetate is as follow:
Rp=k[BPO]^0.97[MVK]^2.80
Therefore, we considered the heterogeneous radical polymerization of one molecular and two molecular reaction.
From the following equation:
R/I=A+B/[I]^1/2
we obtained A=3.85×10^-3l/sec B=3.19×10^-3mol^1/2/l^1/2sec
These values are satisfactory to the overall rate of the polymerization.

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In this experiment, in order to elucidate the powderless etching mechanism between nitric acid and the fine crystallized plate, we made an experiment on the infrared absorption spectral analysis of generated gas and added to tried a few experiments of the chemical reaction.
Experimental: 1) Analysis of generated gas. The Dia Zinc powder (10g) was used as a sample and was immersed in the etching solution, which consists of 13% nitric acid (500ml) at a constant temperature of 25°C. The gas generated during the etching work was analyzed by the infrared absorption spectrum. Analysis showed that the gas generated was Nitrogen monoxide (N₂O). Fig. 3.
According to the results obtained in these studies, it is assumed that the reaction formula is as follows.
4Zn+10HNO₃=4Zn(NO₃)₂+N₂O+5H₂O
Experimental: 2) The measurment of the plate material temperature in both printing area (nonetching part) and nonprinting area (etching part) during the etching operation, using a thermistor thermomter for that measurement. Fig. 5. We confirmed that the temperature of etched area stood around abowt 35°C and that of printirg area around abowt 26°C, thus providing a suggestion worthwhile to consult for temperature adjustment in the actual etching work.
We are pleased to acknowledge the considerable assistance Professor, Dr., Toshio SAKURAI and Dr., Heihachiro OKABE, Tokyo Institute of Technology.

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Anodic oxidation, brush-graining, ball-graining, and sandblast-graining have been known as the graining procedure of lithographic aluminium plates.
Each graining procedure mentioned above have a different effect on printing, that is, the feature of grained surface seems to change according to these procedures.
We considered that some differerce of contact angle might be found when we measured the contact angle of water drop on various grained surfaces.
We made experiments as follows.
1. Difference of the contact angle on plates by various graining procedure.
2. Relation between contact angle and grain roughness of plates.
3. Variation in contact angle before and after counter-etch.
4. Contact angle of Presensitized plate dissolved out sensitive layer.
Our results are as follows
1. The contact angle does not depend on the roughness of the grained surface but depend the graining procedure.
2. Counter-etching with sodium hydroxide reduces the contact angle, and counter-etching with sulfuric acid seems to have no influence.
3. The contact angle of Presensitized plate free from the light sensitive layer is generally small compared with the other plates. This plate is not affected by counter-etching.
4. We found, it is difficult to find a certain relation between the contact angle and the grained surface roughness.
And many problems has been left about the contact angle on grained surface.

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