Lacquering objects

The unique qualities of lacquer ware fully justify this effort. Once hardened, the lacquer surface protects from dampness and mold is relatively scratchproof and remains unaffected by alcohol, hot water, salt, and alkali solutions. Even with everyday use (employing proper care), lacquered objects can survive in an excellent state for a very long time. 

This chapter presents a brief review of the raw material and the history and study of its uses. Technical examination, through the use of a variety of scientific methods, has provided information about the raw material and the film hardening process. Certain diagnostic measurements were used to determine the raw material source (where the trees were grown) and the age of lacquer objects. An extended bibliography is included for those wishing additional details. 

Hazards toxicity, flammability, disposal Precautions necessary These data will alert the conservator to dangers, in working, for users and the environment Lacquering objects may produce toxic vapours... 

In order to prevent recurrence of the corrosion, a lacquer can be appHed. Alternatively, the environment of the object can be strictiy controlled with regard to relative humidity and pollutants. 

A lot of natural as well as technological objects of analytical control are colloidal systems, i.e. human blood, biological liquids, sol and suspension forming in different technological processes (ore-dressing, electrochemical deposition, catalysis and other), food, paint-and-lacquer materials, sewage water and other. 

Protecting the can from the effect of corrosion is very important in order to achieve the very long shelf life that metal cans offer. Discussion with the can manufacturer will ensure the use of the appropriate grades of lacquers on the internal surfaces to prevent primary corrosion. The external surfaces must also be considered in order to prevent secondary corrosion, which will result in leakage. Handling on the filling line must ensure the smooth flow of cans and eliminate any sharp objects that may scratch or pierce them. A lot of moisture is present on the line because of the use of conveyor lubricants or from the pasteuriser, and it is important that cans are dried before being packed, particularly if they are to be shrink-wrapped. Cold cans, below the dew point, must be wanned to ambient temperature or else they will become wet when packed. 

Insects also produce polymers. For example, silk is made by a caterpillar called a silkworm. One silkworms cocoon can contain as much as 900 to 3,000 feet (300 to 900 m) of silk thread. An insect called the Laccifer lacca—or just Lac, for short—lives on trees in India and Southeast Asia. The insects drink the sap from the trees they are living on and produce a polymer that is used to make lacquer and shellac. People use these varnishes to coat and protect ships, houses, wood floors, furniture, and other objects made of wood. 

In the making of snuff bottles and other small items, gourds and other fruits can be placed in wooden or metal molds while they were still growing. The inside of these molds are carved in reverse so that the positive designs will be impressed into the adult fruit. Objects created in this way were often lacquered or decorated after they were removed from the mold. Other fruits molded in this way include tangerines, oranges, and lemons. 

The paint manufacturing industry produces a variety of products. These products are used to protect, preserve and beautify the objects to which they are applied. In general, paints are classified by their proposed function or service applications such as architectural coatings, industrial coatings, special purpose coatings, varnishes, lacquers, etc. The characteristics of most important classes are summarized below. 

The sap of a shrubby tree growing over large areas of Asia has been used to produce a highly durable protective and decorative coating for a wide variety of objects. The finished material, called lacquer, is known to have been used for over 3700 years. It is seen on utilitarian everyday objects such as boxes, trays, and cups, and further serves as a protective and decorative coating on furniture, armor, masks, and sculpture. Furthermore, lacquer ware continues to be used and remains highly prized even today. 

The methods of collecting and refining the raw materials and the production of objects are very labor intensive. Even before the final decoration is applied, the manufacture of high-quality lacquer ware involves up to 30 difierent processes. These include steps in preparation and stabilization of the inner core, application of an undercoating to reinforce the core, and application of the intermediate lacquer layers, each polished and prepared for final decoration. These last decorative procedures may require a great number of multiple layers incorporating a variety of materials. 

Lacquer was probably first used solely as a protective coating decorative elements have evolved with time. Objects may be simply colored in monochromatic red or black, for example, Chinese bowls and carved boxes. Other objects may be highly ornate, with patterns introduced by using metal flakes or foil to produce decorations on the interior subsurface layers. Some pieces may have designs of inlaid mother of pearl still others have a combination of metal-flake patterns and mother-of-pearl inlay. It is common for some objects to have 60-100 individual layers. Hardening and polishing each layer takes from several days to months it might require many years for completion of an article. 

Use Weatherproof and acid-proof mortar and cements, refractory bricks, other molded objects, heat-resistant paints, chemical-resistant paints, protective coatings for industrial buildings and castings, lacquers, bonding agent, intermediate. 

One of the most fascinating stories of the coatings industry involves the production of acetone, butanol, and ethanol by the Weizmann process (11. 12). Because the main objective was to produce acetone for explosives, the butanol piled up until it was found that butyl acetate was an excellent solvent for the new nitrocellulose lacquers. Commercial Solvents Corporation (of Maryland) was formed in 1919 to take over the fermentation plants operating at Terre Haute to make butanol and derivatives. The availability of butyl alcohol and the acetate was of major aid in the success of nitrocellulose lacquers in new automobile paints that permitted a reduction in the time required for painting automobiles from 23 days in 1920 to a matter of about 12 h in 1940 (13). 

Products of the coatings industry—paints, varnishes, lacquers, enamels, chemical coatings, maintenance finishes, and other products both basic and sophisticated—have been used to protect, decorate, and provide functional properties to a host of surfaces and objects. The leveraged value of coatings is exemplified by the contribution of corrosion-resistant primers and of protective and decorative topcoats to the long life of structures, such as buildings and bridges, and to the appearance and durability of automobiles and appliances. 

USE Coloring oils, spirit lacquers, etc. also as stain for zoological, pathological, and vegetable objects like wax, cutin, resin, contents of lactiferous ducts, etc., which are colored red, while cellulose membranes remain uncolored. Approved by FDA for external use only. 

Is PEG always a suitable preservative In my opinion, there are very few situations in which PEG is not suitable as a preservative for wet wood. One, however, is obvious when the object is going to be kept outdoors. The solubility of the PEGs in water makes them leach when it rains. Even with a sheltering roof, the hygroscopicity of the PEGs makes them leach at relative humidities above 80%. A coating of lacquer can protect the object in an outdoor situation and delay the effect of the PEG hygroscopicity, but it cannot be prevented. 

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