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Predecessor
Volume 56, Issue 6
Displaying 1-10 of 10 articles from this issue
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Catalytic Activity of Pigments for Castor Oil Oxidation by Differential Thermal AnalysisHiroshi FUKUI, Tsutomu SAITO, Muneo Tanaka1983 Volume 56 Issue 6 Pages 349-355
Published: June 20, 1983
Released on J-STAGE: November 20, 2012
JOURNAL FREE ACCESSOxidation of castor oil by the pigments was discussed with oxygen gas flow-DTA. The pigments were classified into three groups by the oxidation behavior of castor oil.
Group 1. The type of pigments which promotes the oxidation of castor oil ; Hydrated Chromium Oxide, Red Iron Oxide, Yellow Iron Oxide, Black Iron Oxide, Prussian Blue
Group 2. What has no influence for the oxidation of castor oil ; Zinc Oxide, Kaolinite, Mica, Ultramarine Blue, Silica
Group 3. What inhibits the oxidation of castor oil ; Talc, Titanium Dioxide
The pigments promoting the oxidation of castor oil were the color pigments with the transition elements such as chromium, iron, manganese. The oxidation activity is considered to have no relation to acid-base sites of pigments surface. Moreover, this oxygen gas flow-DTA method was in good agreement with the active oxygen method (AOM).View full abstractDownload PDF (785K) -
Noboru TAKEI, Toyohiko YOSHIDA1983 Volume 56 Issue 6 Pages 356-363
Published: June 20, 1983
Released on J-STAGE: November 20, 2012
JOURNAL FREE ACCESSAccording to Kubelka-Munk theory, optical properties of pigments are indicated by scattering coefficient (S) and absorption coefficient (K). Although there are many reports on the values of S and its applications, data published on S and K values of tinting pigments are seldom2-8).
The values of K and S are affected by particle size, PVC and interaction with vehicle components etc. Although, they are not substantial as refractive index, the knowledge of shapes and magnitude of S, K.-wavelength curves give very useful information on the color, hiding power and transparency of coating films.
Authors determined S and K values with 23 typical tinting pigments including white used in paint and ink industry. The pigments were prepared as 10% PVC nitrocellulose lacquer, then mixed with white base in several concentration and spectral reflectance of its films were measured. The reflectance are corrected by Saunderson' s equation (k1= 0. 04, k2= 0. 4). With modified Duncan's equation, Kt/Sw and St/Sw (t : tinting pigment, w : white) were calculated. From these values and S of white base, St and Kt were determined. These data are shown on Fig. 9-14.View full abstractDownload PDF (672K) -
Mikio IDEI, Noboru TAKEI, Toyohiko YOSHIDA1983 Volume 56 Issue 6 Pages 364-373
Published: June 20, 1983
Released on J-STAGE: November 20, 2012
JOURNAL FREE ACCESSIt is well-known that the color locus from the mixture of some color pigment and white pigment follows loop or curve on the chromaticity diagram. However, it is not clarified why they follow loop or curve. The purpose of the study is to analyze these color loci using Kubelka-Munk theory.
The following results were obtained.
1) A color locus in a mixture of any tinting pigment and white pigment could not be explained from spectral reflectance curve of the tinting pigment. Considering the distributions and the additivity of K (absorption coefficient) and S (scattering coefficient), color loci of their mixtures could be explained.
2) By the simulation of color change for mixture of white pigment and colored pigment which had the model distribution of K and S, the change of chromaticity were explained well.View full abstractDownload PDF (849K) -
Takashi MATSUNO, Hiroaki TAKAYANAGI, Kimio FURUHATA, Masumi KOISHI, Ha ...1983 Volume 56 Issue 6 Pages 374-380
Published: June 20, 1983
Released on J-STAGE: November 20, 2012
JOURNAL FREE ACCESSThe single crystals (0. 2-2. 0 mm) of CaSO3.4 H2O were synthesized in the agar gels at 4°C. Calcium hydroxide suspension and sulfurous acid were used as the reactants. The single crystals of CaS03. 4 H2O were obtained by adding small amounts of sodium citrate to the calcium hydroxide suspension and the agar gels as an additive. The chemical composition of the CaS03.4 H2O single crystal agreed very closely with the calculated values. The density of CaS03.4 H2O single crystal was 1.88 g·cm-3, which was determined by the flotation method. The crystal parameter of CaS03.4 H2O has been determined by the single-crystal X-ray diffraction method. The cell constants were determined by the least-squares procedure from the 2 θ values of 21 reflections measured on a diffractometer using monochromated CuKa radiation.
CaSO3·4 H2O crystal system belongs to monoclinic (a=19. 385 (11) Å, b=11. 192 (4) Å, c=11. 449 (10) Å, β=124. 34 (4) °, Z=12) and hexagonal (aH=19. 390 (10) A, cH=28. 363 (20) Å, Z=54) as shown in Table. 2View full abstractDownload PDF (1198K) -
Radiation-induced emulsion polymerization of methyl methacrylate at low temperatureKeizo MAKUUCHI, Akio KATAKAI, Hiroshi ITO, Naohiro HAYAKAWA, Kunio ARA ...1983 Volume 56 Issue 6 Pages 381-388
Published: June 20, 1983
Released on J-STAGE: November 20, 2012
JOURNAL FREE ACCESSMethyl methacrylate was polymerized in emulsion by Co-60 γ-rays below 19°C a batch reactor by using sodium lauryl sulfate as emulsifier. The conversion-time curves of the polymerization system showed two rate regions, i. e., a fast conversion rate in early stage, and a much slower rate in latter stage. The change in rate occurred at about 70% conversion. The molecular weight of product polymer decreased with increasing conversion during the course of polymerization in latter stage, in contrast to the behavior in early stage. The distribution of the monomer in emulsion in latter stage was evaluated by nuclear magnetic resonance technique. The decrease of the molecular weight with conversion is due to the radiation-induced degradation of product polymer accelerated by the monomers absorbed in the polymer particles.View full abstractDownload PDF (891K) -
Radiation-induced emulsion polymerization of methyl methacrylate at high temperatureRadiation-induced emulsion polymerization of methyl methacrylate at high temperatureKeizo MAKUUCHI, Akio KATAKAI, Miyuki HAGIWARA, Kunio ARAKI1983 Volume 56 Issue 6 Pages 389-394
Published: June 20, 1983
Released on J-STAGE: November 20, 2012
JOURNAL FREE ACCESSMethyl methacrylate was polymerized in emulsion at high temperature by radiation to make clear the features of radiation-induced emulsion polymerization. The viscosity and pH of emulsion obtained decreased with increasing the polymerization temperature. These indicated the formation of acidic products during polymerization at high temperature. From the facts that the acidic products were removed easily by dialysis and the emulsifier used was stable for heat treatment, the acidic products were found to be formed by hydrolysis of low molecular weight polymethyl methacrylate adsorbed on the surface of emulsion particles. The water resistance of emulsion film decreased by the presence of the acidic products.View full abstractDownload PDF (709K) -
Interaction of the three Inorganic Pigments and the Linseed Oil Modified Alkyd ResinKyo TAKAOKA1983 Volume 56 Issue 6 Pages 395-402
Published: June 20, 1983
Released on J-STAGE: November 20, 2012
JOURNAL FREE ACCESSThe interaction of inorganic pigment and synthetic resin was estimated for the degree of the thermal degradation of the linseed oil modified alkyd resin (abbreviated as resin) on the inorganic pigments (Si02, PbCrO2, PbO) by the method of the thermal gravimetric analysis (abbreviated as TGA) and the IR spectrophotometric analysis.
The subtracting curve of the TGA's curve of the coated resin on the Si02 from the TGA's curve of the 100% resin was indicated the effect of the thickness of the coated resin on the Si02 at thermal oxidation reaction, because of the surface of the Si02 was nonreactive.
This subtracting curve of the 10% coated resin on the Si02 (weight ratio of 10% resin to 90% Si02) was indicated to degradated at lower temperature from 50 to 97°C than the degradation tempera-ture of the 100% resin at the same residual weight ratio by TGA.
The effect of thickness of the 1% coated resin was larger from 22 to 24% than the 10% coated resin on the Si02.
The subtracting curve of the TGA's curve of the 10% coated resin on the Si02 from the TGA's curve of the 10% coated resin on the PbCrO4 was revealed the interaction of the coated resin and the PbCrO4, and by this effect, the degradation took place at lower temperature.
Because of the larger interaction of the resin and the PbCrO4, the degradation temperature of the 1% coated resin on the PbCrO4 was so lower downed from 28°C to 34°C.
As the results of this analysis of the same process, the degradation of the resin on the PbO was occurred at three steps.
The ester group of the 1% coated resin on the PbCrO4 was decomposed to 20% at 210°C and was violently decomposed at the upper temperature.
By the reaction of the resin and the PbO, the ester group was decomposed and the carboxylic anion group was produced in the 1% coated resin on the PbO at 120°C.View full abstractDownload PDF (995K) -
X-ray Deterioration Behavior of Polyvinyl Chloride Resin FilmEiki TAKESHIMA, Toshinori KAWANO, Hisao TAKAMURA, Katsumasa AWA1983 Volume 56 Issue 6 Pages 403-411
Published: June 20, 1983
Released on J-STAGE: November 20, 2012
JOURNAL FREE ACCESSIn order to develop a method of predicting the service life of the steel sheet coated with polyvinyl chloride resin within a short time, the deterioration of the coating of polyvinyl chloride resin by continuous X-ray radiation was studied. The results show that
(1) The coating, when radiated with X-ray, is blackened although the surface conditions and gloss thereof substantially remain unchanged. This phenomenon does not happen at the dew cycle weatherometer test.
(2) The dew cycle weatherometer test and the X-ray radiation test are accompanied by extremely different discoloring of coating, leaching of the plasticizer and generation of the coating crack.
(3) The stabilizer of inorganic lead group is different in effect from the stabilizer of organic tin group in that in the case of the former, the hydrogen chloride which is a byproduct of decomposition of the polyvinyl chloride resin is entrapped.
(4) In respect of the dechlorination of polyvinyl chloride resin, decomposition of lead stabilizer and generation of lead chloride, the X-ray radiation test and the dew cycle weatherometer test have a correlationship, the acceleration effect of the X-ray radiation test being much higher. These changes are also affected by X-ray radiation energy and have relations of an exponential function or quadratic function.View full abstractDownload PDF (1316K) -
X-Ray Evaluation of Weathering Resistance of Polyvinyl Chloride Resin FilmEiki TAKESHIMA, Toshinori KAWANO, Hisao TAKAMURA, Katsumasa AWA1983 Volume 56 Issue 6 Pages 412-420
Published: June 20, 1983
Released on J-STAGE: November 20, 2012
JOURNAL FREE ACCESSStudy was made of the coating effect of chrome yellow when applied as a coloring pigment for a polyvinyl chloride resin film and also of the applicability of an X-ray radiation test as an accelerated deterioration test of polyvinyl chloride resin. The results show that :
(1) As compared with the non-coating chrome yellow not subjected to coating treatment, the heavy-coating chrome yellow with the surface coated with alumina and silica is chemically stable. The coating effect is evaluated by the generation of coating crack, discoloring, decomposition of the chrome yellow and generation of lead chloride in the X-ray radiation test and the dew cycle weatherometer test.
(2) In the X-ray radiation test, dew cycle weatherometer test and outdoor weathering test, the decomposition of polyvinyl chloride resin changed with time exponentially, indicating a correlation among them. In the X-ray radiation test, the polyvinyl chloride resin decomposed at a rate 104 times higher than in the outdoor weathering test, which indicates that it is possible by the X-ray radiation test of a very short time to estimate the decomposition rate of polyvinyl chloride resin in the dew cycle weatherometer test or outdoor weathering test.View full abstractDownload PDF (1372K) -
The effect of a low molecular weight additive ins acrylic-melamine resin on curing behaviourTakaharu IZUMO, Satoshi YAMAMOTO1983 Volume 56 Issue 6 Pages 421-425
Published: June 20, 1983
Released on J-STAGE: November 20, 2012
JOURNAL FREE ACCESSIn order to study the effect of low molecular weight additive on curing behaviour of thermosetting resin system, the dynamic viscoelasticity of acrylic-melamine resin with various content of DOP was traced.
The results were as follows.
1) The specific content of DOP accelerates the crosslinking formation.
2) The crosslinking mechanism is not affected by DOP. It is induced that this acceleration is due to the rheological behaviour of curing resin system.
3) These results support the conclusion of our previous report II.View full abstractDownload PDF (512K)
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