Hasil untuk "Paints, pigments, varnishes, etc."

O. Medennikov, M. A. Egorova, N. Shabelskaya et al.

زهرا مختاری شوریجه, مهدی ارجمند, نیازمحمد محمودی et al.

این مطالعه به بررسی سنتز ZIF-67 مبتنی بر کبالت با استفاده از متانول، اتانول و ایزوپروپانول به‌عنوان حلال‌ها می‌پردازد. تأثیر این حلال‌های الکلی بر اندازه ذرات، ریخت‌شناسی و ویژگی‌های ساختاری ZIF-67 با استفاده از روش‌های پراش اشعه ایکس (XRD)، طیف‌سنجی تبدیل فوریه فروسرخ(FTIR)  و میکروسکوپ الکترونی روبشی (SEM) مورد تجزیه و تحلیل قرار گرفت. نتایج نشان داد که انتخاب حلال تأثیر قابل توجهی بر اندازه و یکنواختی ذرات دارد. از بین حلال‌های مورد استفاده، ZIF-67 سنتز شده با ایزوپروپانول بالاترین ظرفیت جذب رنگزای متیلن بلو را با مقدار 1/29 میلی‌گرم بر گرم نشان داد، در حالی که ZIF-67 سنتز شده با اتانول و متانول به ترتیب ظرفیت‌های جذب 94/22 میلی‌گرم بر گرم و 37/19 میلی‌گرم بر گرم داشتند. این آزمایش‌ها تحت شرایط بهینه جذب انجام شدند که شامل pH برابر با ۷، دوز جاذب 02/0 گرم، غلظت اولیه متیلن بلو ۷ میلی‌گرم بر لیتر و زمان تماس ۱۸۰ دقیقه بود. تحلیل ایزوترم لانگمویر، مدل سینتیکی شبه‌مرتبه دوم و ترمودینامیک فرایند نشان داد که فرایند جذب، گرماگیر، خودبه‌خود و مطابق با سازوکار جذب تک‌لایه است. این مطالعه اهمیت انتخاب دقیق حلال در سنتز  ZIF-67  و تأثیر آن بر ویژگی‌های جذب را برجسته می‌کند.

O. Medennikov, M. A. Egorova, N. Shabelskaya et al.

The paper investigates the possibility of thermal processing of waste from the chemical industry – phosphogypsum. It is shown that when phosphogypsum is dried, partial dehydration of dihydrous calcium sulfate occurs, and when calcined at temperatures of 600…1200 °C, complete dehydration occurs. It was found that after heat treatment below 800 °C, the samples actively absorb moisture. During the heat treatment of phosphogypsum in the presence of a reducing agent, two endothermic effects are observed associated with the sequential dehydration of CaSO4·2H2O, and a wide peak of the exothermic effect associated with the thermal destruction of the reducing agent and the formation of calcium sulfide from phosphogypsum. Phosphogypsum samples heat-treated in the presence of a reducing agent acquire the ability to emit a yellow-orange glow under the influence of ultraviolet radiation. Synthesized pigments can be used to produce water-based paints and varnishes.

Andrea Poliszuk, Laura Gelabert, Gabriel Ybarra et al.

Contemporary outdoor mural paintings have been recognized as artistic expressions closely connected with urban communities. These artworks are prone to suffer deterioration due to exposure to harsh environmental conditions. Therefore, knowledge on painting materials used by street artists is mandatory for the preservation of these paintings. In this study, for the first time, the composition of white household paints of three brands from the local market is investigated. Organic and inorganic components are identified by a multianalytical approach using scanning electron microscopy with energy‐dispersive X‐ray spectroscopy, thermogravimetric analysis, attenuated total reflection‐Fourier transform infrared spectroscopy, and X‐ray diffraction. The paints contain a styrene–acrylic copolymer and titanium white in the rutile phase as pigment. Then, two mural paintings are selected to collect samples in order to perform a stratigraphic study and characterize their materials and painting technique. In the mural “Toad on the wrong way,” the use of an acrylic resin as varnish contributes to its conservation. In the red sample of “CIDEC factory,” the identification of Pigment Red 149 (PR149) allows us to attribute the fading of the red areas to the photo‐oxidation reaction of this synthetic organic pigment.

Abed Haddad, Ken Sutherland, Silvia A. Centeno et al.

The richly decorative and imaginative works by French artist Séraphine Louis (1864–1942) have long elicited fascination, and her working methods have often eluded art historians and conservators alike. Working in secret and outside established art circles, Séraphine employed materials such as natural resin varnishes and was said to have used household paints in addition to traditional artists' oil paints. In this study of six works in the collections of the Musée d'Art et d'Archéologie, Senlis (MAA), The Museum of Modern Art, New York (MoMA), and The Metropolitan Museum of Art, New York (MMA), attention was given to Séraphine's choice of colors and paints, in addition to identifying possible additions to or manipulations of painting media by the artist. Technical imaging was carried out using UVF to visualize the extent of Séraphine's use of natural resins. Analysis of the palette relied on XRF techniques and limited sampling for analysis by Raman and µ-FTIR spectroscopies. Overall, the following pigments were identified: lead white, zinc white, carbon-based black, red and brown ochres, umber, vermilion, alizarin lake, rhodamine B lake, Prussian blue, cobalt blue, ultramarine blue, chrome green, emerald green, viridian, cadmium yellow, and lead chromates, including chrome yellow deep and light, zinc yellow, and chrome orange. THM-Py-GCMS analysis of selected samples supported the documentary evidence of Séraphine's use of household oil paints; a single instance of a cellulose nitrate enamel paint was additionally determined by µ-FTIR. The chromatographic analysis also indicated a natural plant resin in her varnishes, probably dammar in combination with pine resin. Overall, this material investigation, accompanied by the art historical record, better reveals the techniques of an experimental painter whose works have come to epitomize French outsider artists of the early twentieth century.

سید علی نظام زاده, رضا امینی, پونه کاردر

محافظت در برابر خوردگی فلزات، سال‌‌‌ها دغدغه‌‌‌ی پژوهشگران بوده است. در نتیجه برای گسترش کاربرد فلزات، از روش‌‌‌های گوناگونی برای افزایش مقاومت به خوردگی آن‌‌‌ها استفاده می‌‌‌شود. در این پژوهش، از میان فناوری‌‌‌های اصلاح سطحی، پوشش‌‌‌های تبدیلی به دلیل تشکیل رسوب یکنواخت بر روی سطح فلز، بهبود چسبندگی لایه‌‌‌ی اعمالی بعدی، کاربری آسان و به‌‌‌صرفه بودن، بیشتر مورد توجه قرار گرفته است. همچنین این پوشش‌‌‌ها مانند یک سد فیزیکی میان زیرلایه و محیط عمل می‌‌‌کنند و علاوه بر محافظت در برابر خوردگی، با افزایش انرژی سطحی، چسبندگی پوشش‌‌‌آلی به زیرآیند فلزی را بهبود می‌‌‌بخشند. در سال‌‌‌های اخیر تلاش شده است تا با اضافه نمودن انواع افزودنی‌‌‌ها، ویژگی‌‌‌های پوشش‌‌‌های تبدیلی بر روی سطوح فلزی بهبود داده ‌‌‌شود. در این راستا افزودنی‌‌‌ها به صورت عناصر خاکی کمیاب (به دلیل سازگاری با محیط‌زیست) به پوشش تبدیلی افزوده شدند تا مقاومت آن را در برابر خوردگی افزایش دهد. اما عیب بزرگ این پوشش‌‌‌ها، تشکیل ترک در پوشش نهایی است. بنابراین، در این تحقیق، به بررسی راه‌‌‌حل برای ازبین‌‌‌بردن ترک در پوشش‌‌‌های تبدیلی، پرداخته شده است.

A. Kolosova, Yaroslav Kudryavcev, A. Tereshko

To produce paints and varnish coatings, there is an opportunity to use a waste of metallurgical production of Yakovlevsky mining and processing complex, Cherepovets, Russia. This waste contains iron oxide as iron oxide pigment. It could be used as an analogue to iron oxide pigment already existing on the market. The authors studied the pigment properties of the waste and the opportunity of using it as a raw material for the synthesis of red iron oxide pigment. The article gives recommendations on the use of the obtained product and shows the opportunity of its application for paint and varnish coatings.

G.A. Eliazyan, S. Margaryan, A. K. Khorozian

Coating compositions for leather finishing consist of film formers, as the main components of the coating film, pigments, plasticizers, solvents and several auxiliary materials (dispersants, stabilizers and others). We have previously shokrn the expediency of using polyethylene acrylate as a film former for hydrophobic finishing of leather compositions (PEA) with "Dali" brand organosilicate preparation, ensuring the film's strength, elasticity and water resistance. In the present work, the pigment concentrate is first prepared in the casein solution, which is mixed with other components of the coating composition. Natural materials are mainly used in the processing of ancient leather (of animal and plant origin) soybean oil, fish oil, casein, beeswax, etc. One of the main requirements for the quality of the coating on leather is the strength of its attachment to the leather, that is, high adhesion with it, both in dry and wet conditions. The amount of adhesion depends both on the chemical nature of the deposited coating and the physicochemical characteristics of the leather surface and its degree of unevenness (after grinding). Adhesion of acrylates in leather is conditioned by Van der Waals forces, in addition, the formation of hydrogen bridges and hydrophobic bonds is possible. The introduction of carboxyl, nitrile, amide and epoxy groups into the composition of polyacrylates significantly increases the adhesion of the coating on the skin. Coating paints based on emulsion film formers are prepared using pigment concentrates and binders (casein, shellac, emulsion film formers, etc. ). In this work, unicolored grounds are used to determine the full coverage of the pigment concentrate in the coating paint. A certain amount of water-soluble or dispersible binders (casein, shellac, wax, emulsion, etc.) are added to the pigment concentrate with the selected color of the finished sample.

M. Ghirardello, A. Candeo, B. Ardini et al.

علی محمدصادق, مهرناز قراگوزلو, سعیدرضا اله کرم

امروزه پوشش‌های نانوساختار به‌عنوان یکی از پرکاربردترین حوزه‌های فناوری نانو مورد توجه قرار گرفته‌اند. عوامل مخرب مانند اصطکاک، سایش و شرایط محیطی در ابزار و بخش‌های صنعت پزشکی باعث تخریب سطح می‌شوند. بنابراین، برای حل این چالش، محققان با استفاده از مهندسی سطح و اعمال نانو پوشش‌ها، درصد تخریب اجزا را کاهش داده‌اند. ایمپلنت های ارتوپدی و دندان به دلیل موفقیت بالایشان به طور فزاینده‌ای در زمینه پزشکی مورد استفاده قرار می‌گیرند. با این حال، عفونت های مرتبط با ایمپلنت هنوز هم رخ می‌دهند و درمان آن دشوار است. استفاده از پوشش فعال روی سطح ایمپلنت برای جلوگیری از عفونت در قسمت‌های پزشکی توصیه می‌شود. در این مقاله مروری به انواع مواد پزشکی مورد استفاده به ویژه خواص آلیاژ فولاد ضد زنگ  L316 و بهبود خواص مقاومت در برابر خوردگی آن با پوشش با نانوذرات کیتوسان و ژلاتین به روش الکتروفورتیک اشاره شده است. همچنین اثر نانوذرات نیز بررسی شده است. مشاهده شد که افزودن نانومواد باعث کاهش میزان رسوب می‌‌شود، اما به دلیل افزایش کیفیت سطح و کاهش تخلخل در پوشش، مقاومت به خوردگی را افزایش می دهد.

V. Sezonov, Krystyna Dikevych

This article analyzes the component composition of inks, paints and dyes, and also gives a general description of one or another type of ink or dye and a classification of some of them. The historical aspect of the manufacture of inks and their components is highlighted. Writing ink was first made in ancient Egypt and China around 2500 BC. The features of paints depending on the type of printing (high, gravure, flat offset, screen) are studied and examples of their application are given. Flat offset inks used in newspapers are usually simple in composition. As for letterpress, although this type is gradually being replaced by other printing processes, it is still used in the production of money, most paper-based forms in printing serial numbers, etc. Gravure inks are similar to flexographic inks, except that ketones and aromatic hydrocarbons can be used as solvents, allowing much greater freedom in the choice of binders. This type of ink for inkjet printing, such as solvent ink, is considered in detail. Solvent ink is a complex physical and chemical system for inkjet printing, consisting of pigment, polymer, film former, solvent and special additives. The structural composition of solvents is characterized, which, getting on paper, undergoes a number of changes over a fixed period of time, as a result of which the dye dries on paper. Ethanol, benzyl alcohol and many other solvents can also be used as carriers. The choice of solvent or solvents often depends on the properties of the writing instrument. The so-called «invisible» ink (UV ink, thermosetting ink, etc.) was studied separately as a kind of protective element. This type of ink is mainly used in steganography, anti-counterfeiting and currency security features, packaging authenticity indicators, brand protection, and secret messages. Conclusions are drawn, emphasizing that understanding the principle of operation of one or another element of protection allows forensic experts of forensic technical examination of documents to effectively identify forgery.

T. Pugacheva, G. V. Malkov, A. Ilyin et al.

Core/shell pigments allow for the combination of the active anti-corrosion effect of the shell and the barrier effect of the core. This makes it possible to obtain anti-corrosion pigments, with a high—protective effect and low toxicity. Thus, the need for a comprehensive study of the properties of these pigments grows more urgent, before their application to paints and varnishes. The hiding power of core/shell pigments comes close to the one of pure polyaniline (PANi), when the PANi content in the pigment reaches 50 wt.%, with sulfuric and phosphoric acids used as dopants. This paper, also, shows that the blackness value of core/shell pigments with 10 wt.% PANi is around 35 and constant; for pure PANi, their blackness value is 40. When PANi content is 5 wt.%, kaolin-based pigment shows the lowest blackness, which happens due to a generally higher whiteness of kaolin. However, when the PANi content surpasses 10 wt.%, there seems to be no influence on the blackness of the core/shell pigments. The core/shell pigment with a 20 wt.% PANi is, optically, identical to a black-iron-oxide pigment. An increase in the PANi content of the core/shell pigment leads to an increase in the oil absorption of the samples. It was found that the dispersion process would be the most energy efficient for core/shell pigments, containing kaolin and talc as a core.

R. Pause, I. D. van der Werf, Klaas Jan van den Berg

There is little information on the actual use of early synthetic organic pigments (SOPs) in art objects, especially those from before 1950. Their presence can, however, pose a challenge to conservation because their chemical composition, as well as their lightfastness and sensitivity to solvents, are often unknown. Here, a study on the non-invasive identification of SOPs in historic pre-1950 varnished paint-outs from artists’ materials manufacturer Royal Talens is presented. The paints were analysed using a handheld Raman device. Spectra were evaluated by recording the spectra of the same samples with a benchtop instrument. This study demonstrated that the identification of SOPs in varnished oil paints with a non-invasive approach is possible and rather straightforward. The handheld Raman device allowed us to identify fourteen SOPs from eight pigment classes. Besides the occurrence of expected and the known SOPs of this time period, there were also some surprising results, like the detection of the triarylcarbonium pigments PG2 and PB8, and the monoazo Mordant Yellow 1.

S. Divya, Subrata Das

T. Poli, O. Chiantore, E. Diana et al.

Metal soaps formation is a well-known issue in oil paintings. Along the lifetime of the painting, carboxylic acids coming from drying oil (free fatty acids, acids from hydrolysis of triglycerides and from oxidation processes) can react with cations of some pigments (in particular, smalt, lead white and zinc white) forming the related carboxylic salts. As observed by many authors, the formation of these carboxylates, with the tendency to migrate and to aggregate, not only modifies the behavior and the aspect of the paint film but also complicates the cleaning approach. In previous works we have demonstrated that a similar pigment reactivity is possible even in presence of natural resins (such as colophony, dammar, mastic, etc) historically used as final varnishes on paintings. In this case, in the reactions the terpenic acids, among the main components of the resins, are involved. In this work, the carboxylates formation kinetics has been studied starting from two representative acids (palmitic and abietic) of painting oils and natural varnishes. Successively, the reactivity of the palmitic acid with the potassium abietate and of the abietic acid with the potassium palmitate has been verified. This investigation aims at clarifying in which way terpenic acids can be involved in the metal soaps reactivity confirming that also surface varnishes may play a significant role in the carboxylates formation and reactivity. It is important to keep in mind that a finishing varnish can be removed and reapplied many times during the lifetime of a painting, thus renewing the provision of reactive terpenic acids at the interface of the painted layers.