A device to trace the evaporation of solvents was investigated by using a thermal conductivity cell as a detector. Some factors affecting solvent evaporation were discussed. The materials used are Epikote 1001, 1004 and 1009 as film forming materials, and rutile titanium dioxide and phthalocyanin blue as pigments. The solvents are ethyl acetate, methyl ethyl ketone and n-butyl acetate. The factors and the results are as follows : 1) The molecular weight of polymer : As the molecular weight increased, the rate of evaporation decreased and the transition concentration at which the rate determining step of evaporation changes from the barrier vapor phase diffusion to the inner solution diffusion decreased. 2) Gas flow rate : Under the higher flow rate of gas, resin concentration dependence of evaporation was observed from lower resin concentration than under the lower gas flow rate. 3) The quantity of sample didn't have an effect on the transition concentration. 4) Temperature : The transition concentration increased as the temperature raised. 5) Pigment : The presence of pigment retarded the evaporation, and lowered the transition concentration.
The fate of maleic anhydride during the synthesis of linoleic acid modified (Oil length : 65%) alkyd resins employed both maleic and phthalic anhydrides, and maleic anhydride only as the dibasic acid was discussed. Each components in obtained alkyd resins was detected by GLC method after hydrolysis of the resin. It was found that the considerable amounts of maleic anhydride was transmitted to the esters of fumaric acid and adducts of linoleic acid, and the formation of the maleic acid ester was small. Therefore, molecular weight and viscosity of maleic alkyd resins was higher than phthalic alkyd resin. In the resin using only maleic anhydride as dibasic acid, their effects was considered significant, such as the linoleic acid adducts of 40. 6% was formed and the resin was gelled at high acid value. Fumaric acid showed similar behavior to maleic anhydride but the transformation to maleic acid ester wasn't found. Succinic anhydride was ineffective on obtained resin properties such as viscosity and molecular weight.
It is well known that the dark and photo-decay of coronacharged photoconductor-polymer dispersion layers are given experimentally as the Inoue's equation V (t) =Voexp (-a √t), and Iida found that the plot between log V (t) and t has a linear relation in which the gradient of this linear line is proportional to the square root of the absolute temperature. There are many explanations and estimations on this coronacharging phenomena. For example, the capacitance and the resistance of the layer change non-linearly with the increase of accumulation of charges in the layer. And, it is also estimated that the surface states of photoconductor change with the temperature and it gives the non-linear effects on the layer's capacitance and resistance. However, it is considered that these assumptions are so complicated that neither the formation of Inoue's equation nor experimental proof will be easily obtained. So, we considered a model in which corona ions diffuse across the layer along an electrical field after chemisorbing into the layer's surface. Then the differential equations which are derived from the transportation theory of nonequilibrium thermodynamics are calculated. And, the solution of these equations satisfies not only the linearity between log V and, √t but also the linearity of the line gradient against the square root of the absolute temperature. Many experimental results support this solution consistently. Therefore, we inferred that corona ions diffuse into the layer and this difiusion speed determines the rate of the dark decay of coronacharging processes. In the case of dark decay process, it seems that the charges of the corona ions, which diffuse to the reverse side of the layer, are neutralized by the positive charges, and they are deposited in the air regions of the grain boundary, or excluded to the outside of the layer. However, in the case of photo-decay process, the electrons-and-holes, which are generated by the light irradiation, neutralize the charges of corona ions at the each surface of photoconductor. It is explained that the corona ions are neutralized rapidly without traveling a long distance. The rate is determined by the diffusion speed along the thickness of around 0. 1, a, then the corona potential decays rapidly in the case of the photo-decay.
Since it has been suggested in the earlier paper that there are two types of desensitizations caused by dyes, namely, (I) desensitization by electron traps and (II) desensitization by positive hole traps, studies have been made on their dependences upon electronic structures of dyes, pAg of (photographic) emulsions and I- addition to emulsions. Characteristic differences between phenosafranine and 9-methylthiacarbocyanine which are thought to cause I and II respectively on the basis of their electronic structures have been observed in their dependences upon the added amounts of dyes, latent image distribution, pAg of emulsions and I- addition to emulsions, and have supported the above-mentioned mechanisms of two types of desensitizations by photographic dyes.
A selective synthesis of 4-nitro-1-naphthylamine, which is a raw material for N-acetyl4-nitro-1-naphthylamine, an excellent sensitizer for poly (vinyl cinnamate), was investigated. Although the original method had been given in Organic Syntheses (ref. 4) the reaction condition was not adequate to the industrial purposes. In the present method, the amounts of hydroxylamine hydrochloride, potassium hydroxide and solvent, required for the preparation of the same amount of the product, are O. 27, 0.29 and O. 18, respectively, and the reaction time is 1/2, compared with those in the original method, although that of 1-nitronaphthalene is 1. 35. The revised synthesis was as follows : potassium hydroxide (5 g) dissolved in methanol (20 ml) is added at once to the ethanol (40 ml) solution of 1-nitronaphthalene (5 g) and hydroxylamine hydrochloride (2. 5 g) maintained at 45°C on stirring. After the stirring for one hour at 50-60°C, the reaction mixture is poured into ice water (500 ml) and the coagulated solid was collected and washed thoroughly with water. The crude product is decolourized by active carbon (3 g) and recrystallized from the ethanol (120 ml) solution. Yield of the purified product is 33. 5% for 1-nitronaphthalene and 27. 9% for hydroxylamine, compared with 45. 8% and 7. 4%, respectively, in the original method. M. P. 195-196°C. Discussions were made on the reaction mechanism using the results obtained by Hückel molecular orbital calculations on π-electron systems. The results, however, did not prove that the present method was selective synthesis of 4-nitro-l-naphthylamine.
1-hydroxylimidazoles were synthesized by the action of ammonia on an equimolecular solution of the aldehyde and the cz-dione monoxime, and also its oxides were prepared by the condensation of two moles of hydroxylamine hydrochlopide with an equimolecular solution of the aldehyde and the c-dione. Among them, it was found out that 1-hydroxy 2- (6-methyl-2-pyridyl) 4, 5-dimethylimidazole only had the photochromic behavior. Therefore, the film prepared by addition of the imidazole to the chlorinated rubber also showed the photochromism and its rate constant was 0. 9 x 10-2 sec-1. The hydroxyl function in 1-hydroxylimidazoles and their oxides was treated with acrylic chloride to the acryloxy group. The copolymers between acryloxyimidazoles or oxides and styrene were obtained. From the results of the immersion tests and the adhesion tests after exposure of the painted specimens, it was recognized that the introduction of imidazole ring to system could improve the both qualities.