The specialists of the Neman company have perfectly mastered the technology of applying polymer powder coating to both ready doors, and on non-standard designs. For this you have everything you need - knowledge, experience, strength and desire. Polymer painting is a waste-free and clean technology that allows you to obtain high-quality decorative, protective and decorative coatings.
Note that the appearance is formed from polymer powders applied to the painted part of the product fabric. Next, the product is heated and held at a certain temperature for several minutes. The low polymerization temperature makes it possible to paint glass and metal using this technology. In the last decade, this technology has gained great popularity and is gradually replacing traditional methods of applying paint and varnish coatings.
One of the finishing options offered by the Neman company is Moire. What is this coating? This is the finish front door, offering a special powder coating structure. So, upon completion of the work there will be a special pattern on the canvas. Speaking figuratively, moire can be compared to the effect that gives sandpaper. The main advantages of this type are: practicality, aesthetics and versatility. Typically, such products are used in cases where it is necessary to obtain the maximum practicality possible. It is also effectively used to hide defects in the outer part of a metal door.
What benefits does a consumer receive when choosing moire coloring?
The main point of the painting method is to spray on previously cleaned metal coating powder paint. You need to know what paint particles get electrostatic charge, which allows the particle to stick to an object that has the opposite charge. Particles that have not had time to settle are captured in the spray chamber and can be used again. After this, the product is placed in a polymerization chamber for subsequent baking of the paint at a temperature level ranging from 180 to 200 degrees Celsius. Thus, a reliable, high-quality and safe decorative and protective design for humans is created on the canvas. Metal doors with Moire painting can be used not only for installation in apartments, cottages, but also in industrial facilities.
The production of “moire”, hammer, crackling, and “antique” coatings is based on the ability of certain paint and varnish materials during film formation, form beautiful patterns in the form of wrinkles, embossing or tears. Such coatings based on liquid paints have long been used in mechanical engineering, instrument making, the electrical industry and other industries. IN Lately similar coatings are obtained using appropriate powder paints. Hammer coatings are especially popular, as they have a smooth surface that does not become dusty and weakly retains radioactive contamination.
Moire coatings (Fig. 11.5, A) obtained by using powder epoxy paint P-EP-135 different colors. Similar
Paints are produced by many domestic and foreign enterprises. The corresponding wrinkled pattern is formed due to the presence of a special additive in the paint, which provides different speed curing of the film former along the thickness of the coating. Paints are applied to the surface using electrostatic spraying; coatings (thickness 80-120 microns) are cured at 180 °C for 15 minutes.
Moiré coatings can also be obtained using liquid paints(MA-224 paint on compacted (polymerized) tung or oitis oil). The coating technology in this case is much more complicated. Paints are applied to a pre-primed surface, usually in two layers with an interval of 5-10 minutes. The formation of the coating is carried out in two stages: at the first stage, the pattern is revealed, at the second it is fixed. Identification of the pattern is carried out at 80±5 °C for 25-40 minutes, the fixing operation is carried out at 100-170 °C depending on the type of paint and its color.
Hammer coatings (Fig. 11.5, B) in appearance they resemble characteristic patterns, obtained by minting metal. This effect is achieved by introducing into liquid enamels non-floating (low-grease) aluminum powder and pattern formers, which are organosilicon compounds - silicone oils, SKT rubber, Vaseline KV-EM-1. The latter, by changing the surface tension of the film former, contribute to its “contraction” (collection into drops) on the surface of the substrate and powder particles. In this case, violation of the continuity of the coating is not allowed.
To obtain hammer coatings, the industry produces melamine alkyd (ML-165 and ML-165M), nitrate cellulose (NTs-221), alkyd styrene (MS-160) and other enamels. Along with aluminum powder, they contain small amounts of covering mineral or organic pigments that give the coating a corresponding color tint. Enamels are usually applied by spraying (1-2 layers) onto a previously prepared and primed surface. Before use, a pattern former is introduced into them in the form of a 10% solution in xylene at the rate of 1-10 g per 1 kg of enamel. A drawing (pattern) is formed immediately after applying enamel to the surface. It is fixed (coatings are cured) in the case of ML-165 and ML-165M enamels at 120 °C for 1 hour, NTs-221 - at room temperature for 24 hours.
Powder paints (P-EP-258 and others) have also been developed to form hammer coatings. When using them, pattern formation occurs at the moment of coating formation due to surface effects in the film. They also contain aluminum powder. Depending on the type of color pigment, they form coatings of different colors and shades.
Hammer coatings made from liquid paints are used for finishing metal and wooden products: devices, movie cameras, sewing machines, cases for devices, etc. Powder paint coatings have the same purpose, but they are suitable for painting only heat-resistant substrates.
Cracked coatings (Fig. 11.5, IN) imitate the pattern of crocodile skin. To obtain them, both liquid and powder paints are used. As liquid formulations Nitrate cellulose paints are used, which are highly filled systems that are diluted with highly volatile solvents, such as acetone. Cracking is caused by the low cohesive strength of the resulting films and large internal stresses that arise during the rapid volatilization of solvents.
Paints are applied over a background layer of cellulose nitrate enamels, the color of which is usually chosen to contrast with the color of the cracking paint. In thick layers the paint cracks with large tears, in thin layers it cracks with small ones. Cracking occurs immediately after applying paint to the surface. After drying from solvents, the coating can be covered with a layer of varnish or enamel.
Recently, these paints have practically lost their importance for environmental reasons and fire hazard. This niche has been firmly occupied by powder paints that are more convenient to use. They are obtained by introducing aluminum powder and special structuring additives into thermosetting powder compositions, which, by stretching the powder particles in the surface layer, imitate the state of a cracked film. Unlike liquid paints, powder paints practically do not create a surface relief (it remains smooth), which contributes to the non-contamination of coatings. The size of the pattern depends on the viscosity of the melt.
Cracked coatings have a purely decorative purpose. Sometimes they are used to finish dashboards, cladding slabs and panels indoors.
Textured coatings (Fig. 11.6) create the effect of a surface with a large “shagreen”, similar to coatings made from paints and varnishes with poor spreading. The most widely used coatings are textured coatings based on thermosetting powder paints. Regulation of film texture is achieved purely by prescription - by introducing additives that change
Rice. 11.7. Antique colored coatings:
A- with aluminum powder; B- with bronze; IN- with zinc powder
Viscosity of melts (aerosil, thermoplastic polymers, etc.). Coatings can be different color, containing reflective pigments and not containing them. An example of compositions of this type are epoxy-polyester paints P-EP-259-T-1 and P-EP - 259-T-2, produced by OJSC NPF "Pigment". The macrorelief of the coatings formed from them makes it possible to hide defects in the surface of metals - casting, stamping, small irregularities with a film thickness of 80-100 microns.
"Antiques" (Fig. 11.7). The term “antique” appeared in coating technology with the development of a large number of powder paints containing flaked reflective pigments and fillers - powders made of aluminum, bronze, copper, zinc and other metals, as well as mica, pearlescent pigments, etc. Variation possibilities decorative effect Such coatings are practically unlimited. They are determined not only by the type of reflective component, but also by its dispersion, the method of introduction into the composition, the nature and amount of color pigments, and the presence or absence of structuring agents.
There are basically two methods of introducing flake pigments into powder compositions: before extrusion and after extrusion. In the first case, powder particles are chaotically distributed in the melt of the film former and, due to its high viscosity, lose the ability to float when producing coatings. A high reflective effect is achieved only in the second case, when the powder composition, after extrusion and grinding, is mechanically mixed with powder. Particularly attractive for obtaining compositions is the bonding process (mixing under moderate heat), in which powder particles are firmly attached to film-forming particles. This eliminates the separation of powder compositions when applied in an electric field. Any thermosetting film formers are suitable for producing antique-type coatings. The powder paint manufacturer Ekolon (St. Petersburg) has achieved particularly great success in developing formulations for such compositions.
Among other decorative coatings special attention deserve paint coatings called "chameleon". Their main feature is the change in color when viewed from different angles. Powder varnishes for chameleon-type coatings are produced on the basis of light-resistant polyester film formers with the use of special pigments, which are SiO2 compounds WITH microlayers TiO2, Fe2O3 and 2Yu2. Such pigments are offered by the company "Megsk".
moire, the name of the fabric) is a pattern that appears when two periodic mesh patterns are superimposed. The phenomenon is due to the fact that the repeating elements of the two patterns follow with slightly different frequencies and either overlap each other or form gaps.A moire pattern is observed when superimposed on each other. various parts tulle curtains.
The concept of "moiré" comes from fabric moire, in the finishing of which this phenomenon was used.
Moiré pattern occurs when digitally photographing and scanning reticles and other periodic images if their period is close to the distance between the photosensitive elements of the equipment. This fact is used in one of the mechanisms for protecting banknotes from counterfeiting: a wave-like pattern is applied to the banknotes, which, when scanned, can become covered with a very noticeable pattern that distinguishes the counterfeit from the original.
In everyday life, moire often appears when scanning printed images. This occurs because the scanner re-rasterizes an image that already has the original raster in it. It can be more simply imagined this way: if you take a tracing paper with one ornament and put it on a tracing paper with the same ornament, but depicted from a different angle, then the resulting ornament will differ from both the first and the second. If you put them so that they coincide, then the first ornament will coincide with the second.
The round “rosettes” at the intersection of two rectangles result in image distortion, which is visible in the first picture.
Moire can also occur due to incorrect installation angles between the lines of primary colors when screening. Both are, in fact, the interference of two sets of raster lines. There are several types of moire rosettes, by the appearance of which you can often find out the cause of moire.
Scanning, in fact, is the modulation of signals in the scanner grid nodes by the brightness of the typographic raster nodes. IN general view the result is a product of two modulated sinusoids (gratings) with different periods of spatial oscillations. One harmonic may have a longer period, equal to the sum periods of both gratings, which causes moire. The second always has a period equal to the modulus of the difference between the grating periods and disappears because it cannot be implemented at a given scanning resolution.
When printing with any set of inks, the most intense (dark) ink, which has a value of 30 to 70% over a large area, can produce moire. That is, if in a CMYK photograph the black channel does not dominate (<10-15 %) то вероятность возникновения различимого глазом муара минимальна. Таким образом можно почти не обращать внимание на жёлтый канал CMYK фотографии. Угол поворота растра между самыми проблемными каналами должен быть как можно ближе к 45°.
When printing “solid” (that is, with >95% coverage), the concept of “raster inclination angle” practically disappears (even if we're talking about about photography).
When two systems of contrasting stripes are superimposed, a pattern appears formed by their thickening in places where the stripes of one system fall into the spaces between the stripes of the other system. The occurrence of such patterns is called moire effect.
The simplest moiré pattern occurs when two systems of equidistant parallel stripes (lines) intersect at a slight angle. A small change in the angle of rotation of one of the systems leads to significant changes in the distance between the elements of the moire pattern.
A moire pattern is also formed when two non-intersecting systems of equidistant parallel lines are superimposed, when the step size of one of the systems is slightly different from the other. Moreover, the smaller the difference in pitch, the greater the distance between the moire fringes. This makes it possible to obtain a colossal increase (millions of times) in the difference in the width of the spaces between the lines. In other words, the moire effect makes it possible to visually detect, without the use of optical systems, minute deviations in almost identical periodic structures. Currently, the moiré method is widely used to control the accuracy of dividing devices for the manufacture of diffraction gratings.
Moiré appears in an electron micrograph of two crystals superimposed so that their atomic lattices are almost identical. Any defect that disrupts the regularity of the crystal structure is clearly visible in the moiré pattern. The magnification is such that it allows one to see displacements of atoms, the magnitude of which is less than the diameter of the atom itself.
If two lattices of equidistant parallel straight lines, slightly different in step size, are moved one relative to the other in a direction perpendicular to the lines, then the stripes of the moiré pattern will move at a speed much greater than the relative speed of movement of the lattices themselves. In this case, the direction of their movement coincides with the direction of the relative displacement of the lattice with a smaller step. Thus, a small movement of one of the gratings results in a large movement of the moiré fringes, which is easy to detect and measure.
Application example:
A method for determining deformations from a pattern of moire fringes, characterized in that, in order to increase the accuracy of measuring deformations, the ratio of the speeds of mutual movement of the deformed and reference meshes and the speed of movement of the moire fringe is determined, and the magnitude of the deformations is judged by the value of this ratio.
The described manifestation of the moire effect has long been used in all measuring instruments with nondus, such as a micrometer or caliper.
The moiré effect can be used to visualize minute changes in the refractive index of transparent media by placing them between gratings. For example, you can visually study the dynamics of the dissolution of two substances.
The same principle allows for express analysis of the quality of optical parts. The lenses are placed between the gratings; the presence of a convex lens increases the elements of the moire pattern, while a concave lens decreases them. In this case, both lenses rotate the pattern in opposite directions at an angle proportional to the focal length. In places where the structure or shape of the lenses is inhomogeneous, the pattern lines are distorted.
Another example of optical control:
An interference method for measuring the wedge shape of optical transparent plates, which consists in focusing a beam of light from a laser using a lens into the plane of a hole in the screen, behind which a controlled plate is installed, differing in that, in order to increase the accuracy and productivity of measurements, from the controlled plate with its In a fixed position, a transparent copy of the interference rings is obtained, the plate is rotated in its plane by 180, the interference pattern is superimposed on the copy, and the wedge shape of the platinum is measured using the width of the moiré fringes formed from the overlap.
A variety of moiré patterns can be created by combining lattices formed by a wide variety of lines, such as concentric circles, spiraling wavy or radially radiating lines from a point, and even families of evenly spaced dots. In this way, it is possible to simulate many complex physical phenomena, such as the interaction of electrostatic fields, wave interference, and others. Some problems of architectural acoustics are solved using similar methods.
In Japan, it has been proposed to use the moire effect to compile topographic maps of objects. The object is photographed through a grid of thin threads, casting a clear shadow on it. The shadow is deformed in accordance with the relief of the object and when it interacts with the real lattice, a moiré pattern appears, superimposed on the image of the object. In the photograph, the distance between the moire lines corresponds to the depth of the relief. This method is very effective, for example, in studying the deformation of rapidly rotating parts, in analyzing the flow of a surface layer of liquid around bodies in medical anatomical studies.
The versatility of the moire method, the ease of converting various quantities with its help, close to IFR, high resolution - all this suggests that inventors will turn to the moire effect more than once in their practice.
When two or more grids (rasters) consisting of lines, dots or other geometric elements are superimposed, a picture appears consisting of alternating dark and light stripes. This phenomenon is called moire effect. A moiré pattern occurs if these two rasters are rotated relative to each other by any amount or have a slight difference in pitch (the distance between adjacent light or dark stripes of the same name).
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