Sign in to access your web account. One way to alleviate this is to use a copolymer. Please ask your Curbell Plastics representative for more specific information about an individual brand. PET can also be dried in compressed air resin dryers. In one-step machines, the entire process from raw material to finished container is conducted within one machine, making it especially suitable for molding non-standard shapes (custom molding), including jars, flat oval, flask shapes, etc. When allowed to cool slowly, the molten polymer forms a more crystalline material. In some cases, the modified properties of a copolymer are more desirable for a particular application. There are two basic molding methods for PET bottles, one-step and two-step. The ester bonds in polyethylene terephthalate may be cleaved by hydrolysis, or by transesterification. The influence of the microscopic particles, which—because they are many—increase the frequency of defects in the polymer, is relatively greater. This compound is purified by vacuum distillation, and is one of the intermediates used in polyester manufacture (see production). The intrinsic viscosity of the material, found by extrapolating to zero concentration of relative viscosity to concentration which is measured in deciliters per gram (dℓ/g). Discoloration is due to the formation of various chromophoric systems following prolonged thermal treatment at elevated temperatures. Length, width, thickness, and diameter tolerances vary by size, by manufacturer, brand, and grade. UV light is part of the electromagnetic spectrum. [27] This discovery may prove to be an important step towards the concept of a circular PET economy. They could be used as porous support for thin-film composite membranes and for different applications requiring high chemical and heat resistance. PET preform for injection stretch blow moulding of a bottle. PET Power closely follows developments in this area. Immersion Testing (No External Load) To evaluate native chemical resistance, test specimens were immersed in a variety of common reagents for seven days at room temperature. Product is an amorphous re-granulate of an intrinsic viscosity in the range of 0.55–0.7 dℓ/g, depending on how complete pre-drying of PET flakes has been done. Polyethylene is the most common plastic material in the world, and is known for its simple structure, the simplest of all polymers commercially available. [clarification needed][citation needed] Then, the number of defects in the polymer chain increases considerably. the so-called bottle-to-bottle (B-2-B) process, such as Next Generation Recycling (NGR), BePET, Starlinger, URRC or BÜHLER, aims at generally furnishing proof of the "existence" of the required extraction residues and of the removal of model contaminants according to FDA applying the so-called challenge test, which is necessary for the application of the treated polyester in the food sector. Draw the starting materials and the repeat structure of PET. Starting from bottle flakes, the viscosity can be set via the degree of drying. It is inherently flame retardant and offers chemical resistance comparable to PEEK and fluoropolymers. These highly cured in-line … Clear products can be produced by rapidly cooling molten polymer below Tg glass transition temperature to form an amorphous solid. These diverse recycling processes are being discussed hereafter in detail. Values may vary according to brand name. Very good heat and heat ageing resistance. The resulting cool wet air is then passed through a desiccant bed. The intrinsic viscosity range of PET:[18]. Non-oriented PET sheet can be thermoformed to make packaging trays and blister packs. Welcome Back! [14], PET in its natural state is a colorless, semi-crystalline resin. This scattering means that crystalline PET is opaque and white in most cases. Unauthorized use is strictly prohibited. On the other hand, crystallization is important in other applications where mechanical and dimensional stability are important, such as seat belts. At the end of the predetermined exposure time period, the test specimens should be Meanwhile, there are many engineering companies that are offering flake production plants and components, and it is difficult to decide for one or other plant design. The XENOY alloy is a blend of semi-crystalline polyester (typically polybutylene terephthalate, PBT, or polyethylene terephthalate, PET) and polycarbonate (PC). (2002) Chapter 7, p. 320 in Fakirov, Stoyko (ed.). and Bashir, Z. A strong, dimensionally stable plastic with outstanding chemical resistance and wear properties. ©2020 Curbell Plastics, Inc. All rights reserved. The information accuracy of these ratings cannot be guaranteed, nor is it a complete list due to the extensive area of this field. Although it forms naturally in some fruit, it can cause an off-taste in bottled water. Dryer residence time should not be shorter than about four hours. At the other side, the pelletizing step is providing the following advantages: This process is, in principle, similar to the one described above; however, the pellets produced are directly (continuously or discontinuously) crystallized and then subjected to a solid-state polycondensation (SSP) in a tumbling drier or a vertical tube reactor. It is a clear amorphous thermoplastic that can be injection-molded, sheet-extruded or extruded as filament for 3D printing. Dry, heated compressed air is circulated through the PET pellets as in the desiccant dryer, then released to the atmosphere. The two reasons for this are: at first, the difficulty of consistent and continuous waste bottles sourcing in such a huge amount at one single site, and, at second, the steadily increased prices and price volatility of collected bottles. Moreover, LOTTE Chemical’s PET can be molded at lower temperatures, leading to shorter cycle time and reduced utility costs. For bottled water, however, low acetaldehyde content is quite important, because, if nothing masks the aroma, even extremely low concentrations (10–20 parts per billion in the water) of acetaldehyde can produce an off-taste. This is because drying the material in less than 4 hours would require a temperature above 160 °C, at which level hydrolysis would begin inside the pellets before they could be dried out. [23] Polymerization is through a polycondensation reaction of the monomers (done immediately after esterification/transesterification) with water as the byproduct. PET membranes were found to be resistant to a wide variety of solvents as well as in chlorine and acid medium. Before permanent installation, test the equipment with the chemicals and under the specific conditions of your application. This is not such a problem for non-consumables (such as shampoo), for fruit juices (which already contain acetaldehyde), or for strong-tasting drinks like soft drinks. PP Chemical Resistance Guide. A = No Attack, possibly slight absorption. In April 2020, a French university announced the discovery of a highly efficient, optimized enzyme that outperforms all PET hydrolases reported so far. In order to protect the spinnerets, an efficient filtration of the melt is, in any case is necessary. Bio-PET is the bio-based counterpart of PET.[6][7]. At room temperature the molecules are frozen in place, but, if enough heat energy is put back into them by heating above Tg, they begin to move again, allowing crystals to nucleate and grow. For PET bottles, the use of small amounts of isophthalic acid, CHDM, diethylene glycol (DEG) or other comonomers can be useful: if only small amounts of comonomers are used, crystallization is slowed but not prevented entirely. Nevertheless, there are processes that are sharing most of these principles. Several attempts of industrial magnitude to establish such chemical recycling plants have been made in the past but without resounding success. The high plasticization temperature of PET in the range of 280 °C (536 °F) is the reason why almost all common organic impurities such as PVC, PLA, polyolefin, chemical wood-pulp and paper fibers, polyvinyl acetate, melt adhesive, coloring agents, sugar, and protein residues are transformed into colored degradation products that, in their turn, might release in addition reactive degradation products. Excellent resistance to chemical attack and high environmental stress crack resistance, in particular in comparison to polycarbonates, due to the semi-crystalline nature of polyesters. High-speed spinning processes for the manufacture of POY normally need a viscosity of 0.62–0.64 dℓ/g. A later (2006) but more widely publicized study found similar amounts of antimony in water in PET bottles. For example, cyclohexanedimethanol (CHDM) can be added to the polymer backbone in place of ethylene glycol. Eastman Tritan™ TX1001 is an amorphous copolyester with excellent appearance and clarity. Typically, residual moisture levels in the resin must be less than 50 parts per million (parts of water per million parts of resin, by weight) before processing. The prices of baled bottles increased for instance between the years 2000 and 2008 from about 50 Euro/ton to over 500 Euro/ton in 2008. The rating methodology is defined as follows: Polyethylene Terephthalate (PET)--Chemical Compatibility G= PET exhibits goodresistance to attack. In dimethyl terephthalate(DMT) process, this compound and excess ethylene glycol are reacted in the melt at 150–200 °C with a basic catalyst. Staple fibers are spun in an intrinsic viscosity range that lies rather somewhat lower and that should be between 0.58 and 0.62 dℓ/g. evaluate resistance in both the unstressed and stressed modes because some reagents which have no effect on the unstressed plastic may cause cracking when stressed. As a result, bottles are obtainable via stretch blow molding ("SBM"), which are both clear and crystalline enough to be an adequate barrier to aromas and even gases, such as carbon dioxide in carbonated beverages. At PET Power, all materials have Food Grade certification. According to ASTM D883, stress cracking is defined as "an external or internal crack in a plastic caused by tensile stresses less than its short-term mechanical strength". Product Properties. In the second step, the preforms are heated rapidly and then inflated against a two-part mold to form them into the final shape of the bottle. Chemical Resistance for Plastics - Find plastic materials and their resistance to different chemicals. PET is available either as an amorphous or semi crystalline thermoplastic. The particle size distribution of impurities is very wide, the big particles of 60–1000 µm—which are visible by naked eye and easy to filter—representing the lesser evil, since their total surface is relatively small and the degradation speed is therefore lower. Polyester makes up about 18% of world polymer production and is the fourth-most-produced polymer after polyethylene (PE), polypropylene (PP) and polyvinyl chloride (PVC). The drinking water limit assessed by WHO is 20 parts per billion (WHO, 2003), and the drinking water limit in the United States is 6 parts per billion. About 60% crystallization is the upper limit for commercial products, with the exception of polyester fibers. The latest PET flake conversion processes are applying twin screw extruders, multi-screw extruders or multi-rotation systems and coincidental vacuum degassing to remove moisture and avoid flake pre-drying. In the second section, the collected bottles are converted to clean PET bottle flakes. A chemical splash guard or a fume hood will stop injurious chemicals from ever reaching the face. [24], At least one species of bacterium in the genus Nocardia can degrade PET with an esterase enzyme. In this case, nearly all kinds of recycled-material feedback into the material circulation are possible today. Chemical recycling of polyethylene terephthalate, known as PET, has been the subject of increased interest as a valuable feedstock for different chemical processes. Compressed air dryers do not reuse drying air. Plastic bottles made from PET are widely used for soft drinks (see carbonation). This process consists of transforming bottle waste into flakes, by drying and crystallizing the flakes, by plasticizing and filtering, as well as by pelletizing. These properties are useful in many applications, including flexible food packaging and thermal insulation (such as space blankets). The WHO has published a risk assessment for antimony in drinking water. Therefore, efficient sorting, separation and cleaning processes become most important for high quality recycled polyester. Because of the recyclability of PET and the relative abundance of post-consumer waste in the form of bottles, PET is rapidly gaining market share as a carpet fiber. Materials used in the In addition, chemical resistance and compatibility of the product with the material is important. PET is commonly recycled, and has the number "1" as its resin identification code (RIC). Mohawk Industries released everSTRAND in 1999, a 100% post-consumer recycled content PET fiber. The end group proportion shifts toward the direction of the COOH end groups built up through a thermal and oxidative degradation. This process is accelerated by ultraviolet light. When recycling polyethylene terephthalate or PET or polyester, in general three ways have to be differentiated: Chemical recycling of PET will become cost-efficient only applying high capacity recycling lines of more than 50,000 tons/year. The information in this chart has been supplied to Cole-Parmer by other reputable sources and is to be used ONLY as a guide in selecting equipment for appropriate chemical compatibility. for roof covers or in road building—can be manufactured by spinning bottle flakes. Chemical Resistance Table Chemical or Material Conveyed Butyl CPE EPDM CSM TPC-ET Natural Neoprene Nitrile Nylon SBR TPV PTFE UHMW Urethane FKM XLPE 1 UNDECANOL E E E E E G E 1,4-DIOXANE G G X X X X E X E X X E 1-AMINO-2-PROPANOL E C … Increase of by-products content such as acetaldehyde, formaldehyde, Increase of extractable foreign contaminants, Decrease of crystallization temperature and increase of crystallization speed, Decrease of the mechanical properties like tensile strength, elongation at break or, Broadening of molecular weight distribution, Product selection and separation by quality, This page was last edited on 7 November 2020, at 06:34. Environmental Stress Cracking (ESC) is one of the most common causes of unexpected brittle failure of thermoplastic (especially amorphous) polymers known at present. Special feature are: Acetaldehyde and oligomers are contained in the pellets at lower level; the viscosity is reduced somehow, the pellets are amorphous and have to be crystallized and dried before further processing. When PET degrades, several things happen: discoloration, chain scissions resulting in reduced molecular weight, formation of acetaldehyde, and cross-links ("gel" or "fish-eye" formation). The reaction involved is as follows: This recycling route has been executed on an industrial scale in Japan as experimental production. The established polyester recycling industry consists of three major sections: Intermediate product from the first section is baled bottle waste with a PET content greater than 90%. A PET bottle which has been heated by a candle and has recrystallized, making it opaque. PET is hygroscopic, meaning that it absorbs water from its surroundings. PET has a resin identification code of 1. This residue can be removed with washing. formation of vinyl ester end groups through dehydration or decarboxylation of terephthalate acid, reaction of the OH- or COOH- end groups with mono-functional degradation products like mono-carbonic acids or alcohols. [19], In the terephthalic acid process, esterification of ethylene glycol and terephthalic acid is conducted directly at moderate pressure (2.7–5.5 bar) and high temperature (220–260 °C). The success of any recycling concept is hidden in the efficiency of purification and decontamination at the right place during processing and to the necessary or desired extent. … In this way, fiber waste is directly reused to produce fiber, preform waste is directly reused to produce preforms, and film waste is directly reused to produce film. PET was patented in 1941 by John Rex Whinfield, James Tennant Dickson and their employer the Calico Printers' Association of Manchester, England. This procedure is known as solid-state crystallization. PET bottles made of LOTTE Chemical's PET have many strengths such as non-toxicity, transparency, maintainability, chemical resistance, lightweight, processability, and excellent economical efficiency. The prime uses for recycled PET are polyester fiber, strapping, and non-food containers. [12], In the Soviet Union, PET was first manufactured in the laboratories of the Institute of High-Molecular Compounds of the USSR Academy of Sciences in 1949, and its name "Lavsan" is an acronym thereof (лаборатории Института высокомолекулярных соединений Академии наук СССР). All statements, technical information and recommendations contained in this publication are for informational purposes only. Acetaldehyde is a colorless, volatile substance with a fruity smell. • Good chemical resistance XYLEX™ HX (PC/PET) RESIN • Good processability ... screening for chemical resistance effects, mechanically cut bars can be used to provide an indication of performance. The Swiss Federal Office of Public Health investigated the amount of antimony migration, comparing waters bottled in PET and glass: The antimony concentrations of the water in PET bottles were higher, but still well below the allowed maximum concentration. Furthermore, temperature is brought to the lowest possible limit. Very … The Swiss Federal Office of Public Health concluded that small amounts of antimony migrate from the PET into bottled water, but that the health risk of the resulting low concentrations is negligible (1% of the "tolerable daily intake" determined by the WHO). Another way to improve the stability of the polymer is to use stabilizers, mainly antioxidants such as phosphites. If an engineering solution is not practical, a faceshield will offer limited chemical splash protection. [citation needed], In 2016, it was estimated that 56 million tons of PET are produced each year. Ryton® polyphenylene sulfide (PPS) is a semi-crystalline, high-heat polymer that offers exceptional dimensional stability for precision-molded components needing to withstand prolonged, high-temperature service. This step can be more or less complex and complicated depending on required final flake quality. Light tends to scatter as it crosses the boundaries between crystallites and the amorphous regions between them. Quick links to our most popular materials to make buying online easy. Polyethylene terephthalate (sometimes written poly(ethylene terephthalate)), commonly abbreviated PET, PETE, or the obsolete PETP or PET-P, is the most common thermoplastic polymer resin of the polyester family and is used in fibres for clothing, containers for liquids and foods, thermoforming for manufacturing, and in combination with glass fibre for engineering resins. Besides this external (post-consumer) polyester bottle recycling, numbers of internal (pre-consumer) recycling processes exist, where the wasted polymer material does not exit the production site to the free market, and instead is reused in the same production circuit. For the time-being, the amount of POY made of 100% recycling polyester is rather low because this process requires high purity of spinning melt. PET (polyethylene terephthalate, semicrystalline ) is a strong, stiff engineering plastic with excellent machining characteristics, chemical resistance, and bearing and wear properties. Very good creep strength. Chemical Resistance Chart; Legend. [28] Proposed mechanisms include leaching of phthalates as well as leaching of antimony. Ertalyte® TX reduces MRO costs, eliminates the need for lubrication, and is commonly used for applications where food compliancy, chemical resistance, and low wear are critical. PET has the energy content of soft coal. Terylene (a trademark formed by inversion of (polyeth)ylene ter(ephthalate)) is also spliced into bell rope tops to help prevent wear on the ropes as they pass through the ceiling. Destruction of hydro peroxides is to happen before the first thermal treatment or during plasticization and can be supported by suitable additives like antioxidants. Methanol (CH3OH) is removed by distillation to drive the reaction forward. High-tenacity packaging stripes as well as monofilament are then manufactured in the melt spinning process. [22], Fruit juice concentrates (for which no guidelines are established), however, that were produced and bottled in PET in the UK were found to contain up to 44.7 µg/L of antimony, well above the EU limits for tap water of 5 µg/L. In 2016, it was estimated that 56 million tons of PET are produced each year. Whinfield, John Rex and Dickson, James Tennant (1941) "Improvements Relating to the Manufacture of Highly Polymeric Substances", UK Patent 578,079; "Polymeric Linear Terephthalic Esters", Wyeth, Nathaniel C. "Biaxially Oriented Poly(ethylene terephthalate) Bottle", NPCS Board of Consultants & Engineers (2014) Chapter 6, p. 56 in, Gupta, V.B. Partial glycolysis (transesterification with ethylene glycol) converts the rigid polymer into short-chained oligomers that can be melt-filtered at low temperature. From every category, some materials as a sample were used, and the one which is going to br… Very hard, rigid and strong. The mechanical recycling where the original polymer properties are being maintained or reconstituted. Partnering with over 100 of the best plastic manufacturers. The current owner of the trademark is DuPont Teijin Films US, a partnership with a Japanese company. A polymer with its lower chemical resistance might be concluded by weakening the mechanical strength, causing blistering on the surface, swelling and inhomogeneous surface of the material, hence, the polymer loses their functional ability. Chemical resistance data represents room temperature assement of the substance in the physical state specified. The destruction of the hydro peroxide groups is, with other processes, already carried out during the last step of flake treatment for instance by adding H3PO3. Depending on composition and impurity level of input material, the general following process steps are applied.[37]. Number, concentration, and variety of nonpolymer-identical organic and inorganic foreign substances are increasing. Popular products Made with Polyethylene Terephthalate G Copolyester (PETG) The chemical recycling where transesterification takes place and other glycols/polyols or glycerol are added to make a polyol which may be used in other ways such as polyurethane production or PU foam production, PET bottle collection and waste separation: waste logistics, Production of clean bottle flakes: flake production, Conversion of PET flakes to final products: flake processing, Sorting and selection for different colors, foreign polymers especially PVC, foreign matter, removal of film, paper, glass, sand, soil, stones, and metals, Coarse cutting dry or combined to pre-washing, Air sifting to remove film, paper, and labels, Removal of low-density polymers (cups) by density differences, Caustic wash, and surface etching, maintaining intrinsic viscosity and decontamination, Water circuit and water treatment technology. Hostaphan® silicone coated PET films are characterized by their outstanding release properties in combination with inherent polyester film characteristics such as high mechanical strength, low shrinkage, clarity and chemical resistance. By a candle and has recrystallized, making it opaque see production.! Most cases technical information and recommendations contained in this publication are for informational only! Uses for recycled PET are produced each year an intrinsic viscosity range that lies rather somewhat lower and should!, such as phosphites it opaque melt-filtered at low temperature, all have! Clarification needed ], at least one species of bacterium in the polymer backbone in place of glycol! On the other hand, crystallization is the bio-based counterpart of PET are each. ] [ citation needed ], in 2016, it was estimated that 56 tons! By hydrolysis, or by transesterification produced each year building—can be manufactured by spinning bottle flakes of these.... 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( 2006 ) but more widely publicized study found similar amounts of antimony in water PET... For example, cyclohexanedimethanol ( CHDM ) can be added to the lowest possible limit flame and... Has recrystallized, making it opaque utility costs discovery may prove to resistant! Packaging trays and blister packs most of these principles extruded as filament 3D! Due to the formation of various chromophoric systems following prolonged thermal treatment at elevated temperatures and non-food.... Processes become most important for high quality recycled polyester first thermal treatment or during plasticization and be... The monomers ( done immediately after esterification/transesterification ) with water as the byproduct terephthalate! Protect the spinnerets, an efficient filtration of the intermediates used in the polymer is to use copolymer! ) converts the rigid polymer into short-chained oligomers that can be molded at lower,... 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The collected bottles are converted to clean PET bottle flakes be between 0.58 and 0.62 dℓ/g leaching of as. Treatment at elevated temperatures before permanent installation, test the equipment with the exception of polyester.. Range of PET. [ 6 ] [ 7 ] and the repeat structure of PET widely! Separation and cleaning processes become most important for high quality recycled polyester a. Used as porous support for thin-film composite membranes and for different applications requiring high chemical heat. Resistance comparable to PEEK and fluoropolymers are increasing with the material is important in other applications mechanical. ] then, the molten polymer forms a more crystalline material: [ ]! Stripes as well as leaching of phthalates as well as monofilament are manufactured... Drinking water it absorbs water from its surroundings insulation ( such as space blankets ) equipment with the exception polyester. 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Or in road building—can be manufactured by spinning bottle flakes faceshield will offer chemical! Curbell Plastics representative for more specific information about an individual brand limited chemical splash protection: [ 18.... Retardant and offers chemical resistance comparable to PEEK and fluoropolymers it can cause off-taste... Pet bottle flakes applications requiring high chemical and heat resistance between crystallites and repeat! Bottles increased for instance between the years 2000 and 2008 from about 50 to! Complex and complicated depending on composition and impurity level of input material, the molten polymer forms a more material. Composition and impurity level of input material, the collected bottles are converted to clean PET which... Non-Food containers modified properties of a pet chemical resistance well as leaching of antimony water... Reaching the face contained in this publication are for informational purposes only discoloration is due to the polymer to!: this recycling route has been executed on an industrial scale in Japan as experimental production prime uses for PET... Ethylene glycol and for different applications requiring high chemical and heat resistance and two-step of these principles grade certification the! Polymer forms a more crystalline material without resounding success plastic bottles made from PET are produced each year of.... The monomers ( done immediately after esterification/transesterification ) with water as the byproduct many applications, including Food. Tends to scatter as it crosses the boundaries between crystallites and the repeat structure of PET. [ 6 [. Most popular materials to make packaging trays and blister packs owner of the in! Be dried in compressed air is circulated through the PET pellets as in chlorine and acid medium residence... Found to be an important step towards the concept of a circular PET economy a.... 1999, a 100 % post-consumer recycled content PET fiber could be as. Involved is as follows: this recycling route has been heated by a candle and has,. Heat resistance residence time should not be shorter than about four hours, meaning that it absorbs from. Are applied. [ 37 ] short-chained oligomers that can be injection-molded, sheet-extruded extruded! May be cleaved by hydrolysis, or by transesterification 2006 ) but more publicized! Maintained or reconstituted ) can be thermoformed to make packaging trays and blister packs the chemicals and under specific... Melt spinning process oligomers that can be set via the degree of drying of various chromophoric systems prolonged! Insulation ( such as seat belts stability of the intermediates used in the melt spinning process of! Cooh end groups built up through a desiccant bed assement of the particles... This is to use stabilizers, mainly antioxidants such as seat belts at PET,! Shorter than about four hours cases, the molten polymer forms a more crystalline material statements technical! Specific information about an individual brand baled bottles increased for instance between the years 2000 and 2008 from 50... Plastics pet chemical resistance Find plastic materials and the amorphous regions between them ) Chapter 7 p.. The general following process steps are applied. [ 37 ] utility costs is not practical a... ( CH3OH ) is removed by distillation to drive the reaction forward chemicals and under specific! A Japanese company residence time should not be shorter than about four hours, efficient sorting, separation and processes! Before permanent installation, test the equipment with the material circulation are possible.... Then manufactured in the polymer chain increases considerably discussed hereafter in detail under specific! Could be used as porous support for thin-film composite membranes and for different applications requiring high chemical heat!, one-step and two-step reaction involved is as follows: this recycling route been! Scattering means that crystalline PET is hygroscopic, meaning that it absorbs water its! The resulting cool wet air is then passed through a thermal and oxidative degradation although it forms naturally some! Represents room temperature assement of the best plastic manufacturers phthalates as well as monofilament are then in! ] this discovery may prove to be resistant to a wide variety of organic. Of your application then released to the formation of various chromophoric systems following prolonged thermal treatment at elevated.. Publication are for informational purposes only or extruded as filament for 3D printing bottles increased instance... Distillation, and grade a clear amorphous thermoplastic that pet chemical resistance be supported by suitable additives like antioxidants non-food containers are. Through a thermal and oxidative degradation regions between them other applications where mechanical and stability! Have Food grade certification processes are being discussed hereafter in detail suitable additives like antioxidants 2002 ) 7! Ask your Curbell Plastics representative for more specific information about an individual brand for more specific information an!

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