Effect Of Pigment Concentration Research Articles

Effect of pigment concentration on NMR relaxometry in acrylic paints.

Acrylic emulsion paint is among the most common media employed by 20th century artists. Since early acrylic paintings have begun to require the attention of conservators, scientists are working to characterize the properties of these paints to facilitate conservation efforts. In this study, we report an investigation of the physical and chemical properties of acrylic emulsion paints using single-sided NMR in conjunction with gloss measurements and scanning electron microscopy-energy dispersive spectrometry. Combining the data from these techniques gives insight into pigment-base interactions and the acrylic curing process, showing that as pigment concentration is increased in paints, the amount of acrylic base adsorbed to pigment particles increases, resulting in films with differing relaxation times. This research both emphasizes and contextualizes the utility of NMR relaxometry in studying cultural heritage objects and prompts further study into the effects of pigment concentration on the curing and conservation of paint films.

Effect of the Pigment Concentration on the Dimensional Stability and the Melt Flow Index of Polycarbonate

This study is focused on the effect of pigments on polycarbonate (PC), especially the dimensional stability and flow properties of this material. This polymer is commonly used in the plastics industry and the most common processing of this polymer is injection molding technology. Three different pigments made by Lifocolor company were selected for PC staining. In addition, six different concentrations of aforementioned pigments were used. It is worthwhile to note that the pigments in the polymer matrix acted as a filler. Just like fillers, the pigments also influence the shrinkage of the polymer in both the main and secondary directions. The paper also deals with the effect of pigment concentration on the melt index (MFI). It was shown that the presence of pigments reduces the thermal mobility of the macromolecular chain. Melt flow index changes were also directly tied to the changes of the viscosity, which was also affected by the pigments. It can be expected that the viscosity might not remain the same even at varying shear rates.

Effect of pigment concentration and particle size of TiO2 support on performance of chemochromic hydrogen tape sensor

A chemochromic hydrogen tape sensor has been developed to detect hydrogen leaks using titania (TiO2) supported palladium oxide (PdO) pigments encapsulated within a silicone matrix. This study has been carried out to investigate the effects of pigment (PdO-TiO2) concentration and particle size of TiO2 support on detection performance in terms of color contrast of a chemochromic hydrogen tape sensor. The irreversible hydrogen tape sensors were tested with different concentration from 0.2 wt% to 10.0 wt%. Several pigments were synthesized using three different TiO2 support with particle sizes ranging from 100 nm to 5 μm. The experimental results exhibit that the color of the pigment with 0.2 wt% shows distinctive color change in minimum and the optimal pigment concentration for silicone matrix type irreversible tape sensor is 3.0 wt%. In addition, TEM analysis revealed that the PdO particles become larger and agglomerated as increasing the particle size of TiO2 support. The pigment with Aldrich TiO2 particle size ≤5 μm has a good performance than smaller one.

MarkingBactrocera dorsalis(Diptera: Tephritidae) with Fluorescent Pigments: Effects of Pigment Colour and Concentration

Daylight fluorescent pigment powders are frequently used to self-mark tephritid flies that are released in sterile insect technique programmes and for studies on their population ecology, movement and behaviour. This study was conducted to determine the effects of pigment colour and dose in marking the Oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae). Six pigment colours (Astral Pink 1, Blaze 5, Stellar Green 8, Lunar Yellow 27, Comet Blue 60 and Invisible Blue 70) were applied to pupae at doses of 0, 2, 4, or 6 g/l. Under laboratory conditions, pigment colour had a small but significant effect on the number of partially emerged and deformed adults; the fewest of these were observed when flies were marked with Astral Pink 1. Pigment concentration, on the other hand, had no effect on adult emergence, partial emergence, deformed adults and mortality on the last day of eclosion. There was no significant effect of pigment colour on adult survival under laboratory and semi-field conditions. Under laboratory conditions, however, there was an effect of pigment concentration on adult survival depending on pigment colour. Visibility under an ultraviolet light and persistence of marks was significantly affected by pigment colour and concentration when observed under laboratory conditions, but not under semi-field conditions. Regardless of colour or dose, pigments used in the study were visible for at least 14 days, but began to fade by 21 days after adult eclosion. To mark B. dorsalis under temperate, warmsummer African conditions, all pigment colours tested in this study may be applied at 2–4 g/l pupae. Recaptures of marked and released flies may be underestimated as the flies age.

Effect of Pigment Concentration on Mechanical Properties of Polycarbonate

This experimental study deals with the influence of pigments on the mechanical properties of polymeric polycarbonate material Lexan 923c, which is commonly used in industry and is being processed with injection technology. This material was stained with three different pigments from Lifokolor. It was also stained with 6 different concentrations of selected pigments. Emphasis was placed on measuring the tensile strength, impact strength and hardness of polyurethane mixtures.

Modelling the properties of pigment‐dyed polyester/cotton sheeting fabrics by response surface methodology

The aim of this study was to model the effect of pigment, binder and fixer concentrations on the rubbing fastness, crease recovery, tear strength and stiffness of pigment‐dyed polyester/cotton sheeting fabrics. The design and analysis of experiments were carried out using Minitab® statistical software according to the central composite design of response surface methodology. It was found that an increase in the binder concentration significantly improves the dry rubbing fastness, crease recovery and stiffness of the fabric, with a corresponding decrease in fabric tear strength, without significantly affecting the wet rubbing fastness. An increase in the fixer concentration significantly improves both the dry and wet rubbing fastness and crease recovery, with a decrease in fabric tear strength and stiffness. The effect of binder and fixer concentrations on crease recovery was not linear and there was significant negative interaction between these factors for dry rubbing fastness. The effect of pigment concentration was not found to be statistically significant for the types and range of concentrations of pigment, binder and fixer used in this study.

Evaluation of the corrosion performance of zinc-phosphate-painted carbon steel

Abstract The effect of pigment concentration ( C p ) on the corrosion resistance properties of zinc phosphate paints based on epoxy and chlorinated rubber has been investigated by using accelerated corrosion tests (salt spray, cyclic climatic change) of painted carbon steel samples combined with electrochemical impedance spectroscopy. Results show that all the paints act as a protective layer, and the corrosion behaviour of the painted steel samples was found to be dependent on C p . The physicochemical properties of a zinc phosphate coating are affected by the pigment concentration and the nature of the resin. There is a critical value of C p above which many such properties change abruptly. Characterization of the corrosion products was performed by scanning electron microscopy coupled to energy-dispersive X-ray spectroscopy. This analysis showed the presence of a mixture of iron and zinc oxide, which results from attack of the metallic support and reaction of the pigment.

Spectroscopic investigation of the anisotropy of a liquid crystal matrix doped with photosynthetic pigments: effect of pigment concentration on the deg

The macroscopic order parameters of the homogeneously aligned liquid crystal (MBBA) with dissolved photosynthetic pigments (chlorophyll a, chlorophyll b and β-carotene) were determined using polarized absorption, emission and Raman scattering methods. Assuming the cylindrical symmetry of the pigment orientation around the liquid crystal director, the experimental and calculated values of the order parameter were correlated by using the distribution function of the nematics. It was shown that the order parameter of the matrix is dramatically destroyed by a high chlorophyll concentration (3 × 10 −3 M) whereas over a wide range of concentration the carotene did not change the matrix order.

Model systems for photosynthesis - III. Primary photoprocesses of chloroplast pigments in monomolecular arrays on solid surfaces

By means of the Langmuir-Blodgett technique, monomolecular layers containing chloroplast pigments and lipids have been prepared and transferred from a water surface to solid substrates for spectroscopic study. The absorption spectra of such monolayers of pure chlorophyll a and b have been characterized on several different surfaces. Phytol and M 2+ -1:1 stearate–oleate have been used as inert, transparent layer diluents for the chlorophylls to enable the effect of pigment concentration on the absorption and fluorescence spectra to be studied. Self-quenching of the fluorescence of both chlorophylls has been observed and the chromophore separation at the half-quenching concentration is compared with similar data for monolayers on the surface of water, as well as solid and solution systems. Energy transfer between chlorophyll b and a within a monolayer has also been investigated, and found to involve essentially irreversible transfer of excitation energy from b to a . Experiments involving the quenching of chlorophyll fluorescence by quinones in the monolayer leads to the conclusion that the efficiency of quinone quenching is not enhanced at high chlorophyll concentrations. The monolayer properties of the photosynthetically important quinone, plastoquinone A , were investigated, and it was found to form very unstable layers, unsuitable in the present work.

Optical Properties of Coatings. Effect of Pigment Concentration

Optical Properties of Coatings. Effect of Pigment Concentration

合成樹脂塗料の光沢におよぼす顔料濃度の影響

合成樹脂塗料の光沢におよぼす顔料濃度の影響