Paint Technology Research Articles

Mini articles

Moldflow is fundamental to the concept of Granular Injected Paint Technology (GIPT) for in‐mould painting of injection moulded parts which is at present in an advanced state of development. Funded by the EPIC club of 25 companies, the work is being carried out at the Rover Advanced Technology Centre at Warwick University.

Functional coatings on glass using ORMOCER�-systems

Sol-gel derived ORMOCER® materials (organically modified ceramics) have been developed for the functionalization of glass. The adjusted coating systems can be applied in optical quality by conventional paint technologies. Good long-term adhesion, scratch and abrasion resistance, stability against weathering and resistance towards corrosive delamination are additional outstanding advantages of such coating systems. The ORMOCER® coatings can also carry additional functions. For example, the surface polarity of glass can be modified. Hydrophilic as well as extremely hydrophobic surfaces can be attained. The contact angles measured with water range between 10° and 110°. Furthermore, colouring of glass articles is possible with coatings containing chromophores.

In Pursuit of Protein Folding

Johnson Research Foundation, Department of Biochemistry and Biophysics, University ofPennsylvania School of Medicine, Philadelphia, PA 19104–6059Exploring the “Anfinsen trail,” the pathway by which unstructured proteins spontaneouslyfold to their native functional form, has become a central goal of the protein chemists. Inorder to understand a biochemical pathway, one wants to isolate and describe theintermediate structures that lead from precursor to product. Unfortunately the intermediateforms that define protein folding pathways cannot be isolated or studied by the usualmethodologies, however powerful, because folding intermediates are by definition unstable.Nevertheless, two reports in this issue, one by Miranker et al. on page 896, the other byJennings and Wright on page 892, are able to present fairly detailed structural informationon some kinetic folding intermediates in lysozyme and myoglobin, even though theseephemera only exist for less than 1 s during the folding process (1, 2). A related researcharticle by Mayo and Baldwin on page 873 describes some characteristics of equilibriumunfolding intermediates in ribonuclease A that exist transiently at infinitesimal levels inequilibrium with the native state (3).The folding experiments depend on a recently developed method (4) to obtain kinetic andstructural information on partially folded protein forms that fly by on a millisecond timescale. The intermediates were labeled in-flight in a structurally sensitive way, in essence bywriting on them with a brief pulse of chemical spray paint at any given point of time duringfolding. The painting technology (see figure) relies on the naturally occurring exchange ofhydrogens between water and the peptide group NH hydrogens distributed uniformlythroughout every protein molecule (5).The protein in D

Dielectric properties of a standard epoxy resin

Acta PolymericaVolume 40, Issue 2 p. 134-135 Short Communication Dielectric properties of a standard epoxy resin S. Swarup, S. Swarup Department of Oil and Paint Technology, Harcourt Butler Technological Institute, Nawabganj, Kanpur-208002, IndiaSearch for more papers by this authorS. Chandra, S. Chandra Department of Oil and Paint Technology, Harcourt Butler Technological Institute, Nawabganj, Kanpur-208002, IndiaSearch for more papers by this authorM. Zulfequar, M. Zulfequar Department of Physics, Harcourt Butler Technological Institute, Nawabganj, Kanpur-208002, IndiaSearch for more papers by this authorA. Kumar, A. Kumar Department of Physics, Harcourt Butler Technological Institute, Nawabganj, Kanpur-208002, IndiaSearch for more papers by this author S. Swarup, S. Swarup Department of Oil and Paint Technology, Harcourt Butler Technological Institute, Nawabganj, Kanpur-208002, IndiaSearch for more papers by this authorS. Chandra, S. Chandra Department of Oil and Paint Technology, Harcourt Butler Technological Institute, Nawabganj, Kanpur-208002, IndiaSearch for more papers by this authorM. Zulfequar, M. Zulfequar Department of Physics, Harcourt Butler Technological Institute, Nawabganj, Kanpur-208002, IndiaSearch for more papers by this authorA. Kumar, A. Kumar Department of Physics, Harcourt Butler Technological Institute, Nawabganj, Kanpur-208002, IndiaSearch for more papers by this author First published: February 1989 https://doi.org/10.1002/actp.1989.010400215Citations: 2AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume40, Issue2February 1989Pages 134-135 RelatedInformation

Characterization of phosphate crystal nucleation and growth on cold-rolled steel

The formation of a dense, phosphate crystal coating on a steel surface is of prime importance in paint technology to prevent corrosion and to provide a proper substrate for paint adhesion. Crystal nucleation and growth, from an immersion phosphating bath, was examined in detail by infrared spectroscopy, scanning electron microscopy, x-ray diffraction, and electron spectroscopy. The application of high-spatial-resolution Auger electron spectroscopy, which probes individual crystals and substrate regions between crystals, was especially useful and yielded new information on the growth of phosphate coatings. In the system studied, the 15-nm-thick native oxide layer is removed in the first 5 s of immersion as the iron surface dissolves in the bath. Phosphate crystals are identified as nearly all phosphophyllite [Zn2Fe(PO4)2⋅4H2O], but with surfaces enriched in Ni and depleted in Zn. No precursor species form prior to the phosphophyllite growth, in contrast to observations on other phosphating systems. The combined application of our instrumental characterization techniques, together with our experimental protocol, is a powerful method for examining the initial steps in the formation of many surface coating materials.

Micro‐encapsulation and microcapsules; new tools in paint technology

From time to time a new technique is developed which makes it possible to enahce largely the properties of existing coating materials and, even more important, to develop essentially new organic coatings. A fine example of such a new technique is micro‐encapsulation.

塗料概論

塗料概論

Variations in reflectance of pigmented material with particle size and refractive index: An experimental and theoretical study

The multiple-scattering technique proposed by Mudgett and Richards is the first applicable rigorous theory permitting the computations of reflectance of pigmented surfaces from the size and refractive index of pigments. The validity of this theory is established by comparing the experimental values of the reflectance of four paint samples with the theoretically predicted values. A further theoretical study on the variations in reflectance with particle size and refractive index (real and imaginary part of the refractive index) is carried out covering the range of relevance to paint technology. The study revealed that the error in the real part of the refractive index does not introduce a significant error in reflectance values. A small error in the absorption index, however, considerably changes the reflectance values and the error in particle size significantly affects the results in absorbing systems rather than in non- or weakly-absorbing systems.

People

Peter J Attwood has been appointed area sales manager for Binks‐Bullows Ltd. In his new post Mr Attwood is responsible for sales of all areas of spray painting technology, extending from manual spray guns to large industrial spraybooths, high speed electrostatics and robot painting systems.

Glidden buy British technology from Macpherson

Macpherson PCL, one of Britain's leading paintmakers, have signed a long term licence agreement which will allow the Glidden company of Ohio, USA to use an advanced paint technology, developed by Macpherson in Britain, throughout the USA, Canada and Mexico.

Creative advances in the coating industry

The Paint Research Association's sixth International conference was held in Brussels from November 4th to 6th under the above title. Like its predecessors, it was concerned with developments at the very frontiers of knowledge, and attracted over 200 participants from over 100 companies from Europe, Japan and the United States of America. Most representatives were from paint or raw material manufacturers. Participants, who recieved extended abstract of the papers, were well‐pleased with the Conference, which formed part of the celebration of the P.R.A.'s Diamond Jubilee. The founder‐members would be delighted to see the P.R.A.'s role in bringing together so many distinguished lecturers and important advances in paint technology, described in 17 papers from so many countries; four sessions enabled good time for discussion periods.

Starwars and the paint industry

July 1986 that august body, the Paintmakers Association, met to throw it about in delightful Torquay. It can be said at once they did not foozle but, can it be stated their machinations were of a profound nature? They spoke of teaching modules and moaned about competition from that traditional (and world renowned) centre of paint technology learning, the Polytechnic of the South Bank. They showed a video about young people replete with hackneyed phrases: ‘industry is a rat race; industry is a dirty boring factory.’ (What's new Mr Magoo?) They complimented themselves on their novella Blight. The titanium dioxide boys came up for their monthly dubbing. On a more interesting note Disraeli was resurrected: ‘Change is a constant’ and, perhaps most interesting of all, Mr Julian Oliver of ICI, spoke on effective government lobbying.

Comment

Appearing on page 4 of this issue is an article by Keith Hammond on ‘Star Wars and the Paint Industry’. Apart from administering a mild admonishment to the Paintmakers Association for not leaving paint technology learning to the Polytechnic of the South Bank, the author presents his case for thinking that we might get some paint business through the SDI (star wars) project. However, what we found particularly intriguing were his sideswipes at the EEC, with reference to ‘EEC hit squads are dropping into the most unlikely places’. And in his final paragraph: ‘I'm sorry old boy but it's not possible for you to cross my threshold, let alone cart away my records, without a warrant from a local JP’.

Outlines of paint technology

(1985). Outlines of paint technology. British Corrosion Journal: Vol. 20, No. 2, pp. 60-60.

NEW TECHNOLOGY ANTIFOULING PAINTS: U.S. GOVERNMENT RESEARCH AND ASSESSMENT

ABSTRACTMarine fouling growth on the hulls of ships results in unacceptable increases in drag and consequent increases in fuel consumption. Conventional paints cannot maintain hulls free of fouling for the extended operating cycles now being imposed. Accordingly, new antifouling paints featuring organometallic polymer (OMP) toxicants have been developed at a U.S. Government laboratory in response to these requirements. In addition, commercial paints based on the use of OMP biocides have become increasingly available in the last several years, most of which have ablative properties that enhance antifouling performance and promote retention of smooth surfaces. Screening tests that include static and dynamic panel exposure and laboratory evaluation of coating properties are being conducted to qualify candidate materials for ship trials.This paper describes several ship trials that are now underway on various types of ships. Over twenty different commercial and U.S. Government specification paints have been applied as patches, as bands, on entire hulls, and on exposure test panels mounted on bilge keels. Periodic inspections utilizing diver‐operated still and video cameras are made. The factors of ship power, paint condition, and hull roughness are being correlated for selected test vessels.New trends in antifouling paint technology are also discussed, as are problems associated with application and removal of toxic paint materials.

People

R. J. Woodbridge has been appointed technical manager of Berger Decorative Paints. Since joining Berger 42 years ago, Dick has had wide experience in all fields of decorative paint technology, and been responsible for a number of significant advances in emulsion paints. As a recognised expert in this field, he has presented a number of authoritative papers at international symposia.

Estimation of the Kubelka—Munk scattering coefficient from single particle scattering parameters

Computer colour matching of paints is based on the determination of the Kubelka—Munk absorption (K) and scattering coefficients (S) of pigments. K and S are sensitive to particle size in the range of sizes employed in paint technology. The K—M theory does not provide any guidelines for the correction of the values of K and S with a change in particle size. On the other hand the Mie theory linear scattering coefficient can be calculated from a knowledge of size and refractive index of the pigment. A number of relations correlating the K—M scattering coefficient and the linear scattering coefficient have been proposed in the literature. Attempts are made to estimate the K—M scattering coefficient using a relation suggested by Mudgett and Richards and to make a comparison with experimental values. The Mie theory equations being complex, simplified equations applicable to pigment sizes for the calculation of Mie theory parameters are proposed. The viability of the simplified equations has been established by comparing the results with those obtained using the full Mie equations. The K—M scattering coefficient for titanium dioxide pigments has been determined from reflectance measurements. The particle size of titanium dioxide has been determined by a light scattering method. The K—M scattering coefficient calculated from the linear scattering coefficient obtained using the simplified expressions agrees with experimental results. This suggests a method for the correction of the values of K and S with changes in pigment particle size.

Outline of Paint Technology

Outline of Paint Technology

Electrodeposition coating process for automobile bodies.

The earlier electrodeposition process was mainly pursuited for the quality control in terms of mass production. However, the coating efficiency was picked up to be a serial problem from a standpoint of the harmony between natural circumstances and human's living-life conditions and the recovery usage of the paint was earnestly searched. This trend led to the development in various technical fields.The second impetus on further improvement of electrodeposition paint was due to oil crisis in 1973. The new technology relating to save-energy was developed. In the paint industries, the further improved anti-corrosive performance was strongly demanded. This demand also involved the development of new materials for automobile bodies and even the design of bodies structure.In this report, the introduction of electrodeposition process into automobile industries in Japan is hystrically reviewed and the electrodeposition mechanism and the mechanism which deposited materials from the coating film are briefly explained. As the demand for anti-corrosive performance is increased, the coating system in which the anodic oxidation and the dissolution from the object metal can not occur, was aimed and recently it was rapidly accepted as the superior system. On the other hand, there is an opposite opinion for this trend on the basis of the metal analysis detected in the deposited film. The characteristics of cationic electrodeposition, in particular, the superior corrosion resistance with regard to the metal dissolution in the whole electrodeposition process is explained.In Chapter III, throwing power which is characteristic for electrodeposition process is described. It is referred that throwing power is not necessarily determined by the paint performance. Even the electrodeposition coating system, the areas into which the paint liquid does not intrude can not be coated. And it is pointed out that the design of bodies structure is inevitably necessary as well as the improvement of paint performances.In Chapter IV, the role of the main component, vehicle resin, is introduced. The devices which disperse resin into solvent 'water', and factors which determine the polarity of electrodeposition are explained. And the typical resin structure is shown. The paint performance is greatly effected by the vehicle resin, but it is also deeply related how the paint is produced and how it is coated. Therefore, it is inferred that the paint performances are relatively estimated.In Chapter V, the whole system of electrodeposition coating process is given. The so-called 'closed-loop system' which is remarkably characteristic in electrodeposition process, and which is suitably fitted for mass production of automobile bodies is explained. Besides, the pH control technology of paint bath and the possibility on its future development are referred. The further improvement of the recycle usage technology of paint is pointed out and the possibility to reply for the social needs such as save-energy and less polution is explained.In Chapter VI, the present status of electrodeposition process and various technical problems are explained.The summary of this review and authors' views for future development are given in the final chapter.

The New Painting Technology for the Eighties and Beyond

SummaryA commercially viable alternative to the traditional baking of industrial paint finishes is described wherein a room temperature 10 minute catalysing cycle replaces a typical 30 minute 180°C baking schedule. Specifically formulated acrylics, expoxies, alkyds and urethanes are exposed to a contained, mildly turbulent atmosphere containing controlled parts per million of specific catalysts to achieve rapid room temperature drying. Thus the way is opened for the painting of heat sensitive substrates, plastics, partially and fully assembled items, finally breaking the present industrial tyranny of high temperature paint drying on production lines.