LIST of BLOGS on LACQUERS, PAINTS and THINNERS

Post 499  by Gautam Shah

1 UNDERSTANDING LACQUERS

https://interiordesignassist.wordpress.com/2015/08/16/understanding-lacquers/

2 LACQUERS or NC LACQUERS

https://interiordesignassist.wordpress.com/2014/04/27/lacquers-or-nc-lacquers/

3 SOLVENTS for THINNERS

https://interiordesignassist.wordpress.com/2015/08/09/solvents-for-thinners/

4 WOOD SURFACE FINISHING

https://interiordesignassist.wordpress.com/2015/07/13/wood-surface-finishing/

5 PAINT THINNERS Part 2

https://interiordesignassist.wordpress.com/2015/05/14/paint-thinners-part-2/

6 PAINT THINNERS Part 1

https://interiordesignassist.wordpress.com/2015/05/08/paint-thinners-1/

7 ROSEWOOD

https://interiordesignassist.wordpress.com/2015/03/26/rosewood/

8 INDUSTRIAL PAINT FINISHES

https://interiordesignassist.wordpress.com/2015/03/07/industrial-paint-finishes/

9 APPLICATION of COATINGS

https://interiordesignassist.wordpress.com/2015/01/09/application-of-coatings/

10 COATINGS -Surface finishing technologies

https://interiordesignassist.wordpress.com/2014/11/08/coatings-surface-finishing-technologies/

11 CLEAR COATINGS

https://interiordesignassist.wordpress.com/2014/09/12/clear-coatings/

12 FILM FORMING PROCESS in COATINGS

https://interiordesignassist.wordpress.com/2014/09/03/film-forming-process-in-coatings/

13 WOOD SURFACE PREPARATIONS for CLEAR COATINGS

https://interiordesignassist.wordpress.com/2014/04/28/wood-surface-preparations-for-clear-coatings/

14 SHELLAC COATINGS and FRENCH POLISHES

https://interiordesignassist.wordpress.com/2014/04/26/shellac-coatings-and-french-polishes/

15 VARNISH

https://interiordesignassist.wordpress.com/2014/04/25/varnish/

16 MULTI COATS of PAINT SYSTEMS

http://talking-interior-design.blogspot.in/2014/03/multi-coats-of-paint-systems.html

17 WOOD FINISHES

http://talking-interior-design.blogspot.in/2014/07/wood-finishes.html

18 CLEAR COATINGS

http://talking-interior-design.blogspot.in/2015/03/clear-coatings.html

19 CEMENT SURFACE FINISHES

http://talking-interior-design.blogspot.in/2015/06/cement-surface-finishes.html

20 CRAFT of WALL PAINTING (Neolithic)

http://talking-interior-design.blogspot.in/2014/02/the-craft-of-wall-painting-neolithic.html

21 CRAFT of WALL PAINTING (Palaeolithic)

http://talking-interior-design.blogspot.in/2014/01/the-craft-of-wall-painting-palaeolithic.html

22 COATINGS

http://talking-interior-design.blogspot.in/2013/09/coatings.html

23 COATINGS Iron age

http://talking-interior-design.blogspot.in/2013/09/coatings-iron-age.html

24 PRIMITIVE COATINGS Surfaces, Materials and Techniques

http://talking-interior-design.blogspot.in/2013/09/primitive-coatings-surfaces-materials.html

25 LIME-WASH

https://interiordesignassist.wordpress.com/2014/06/01/lime-wash/

26 PAINTING WHITE – 1

https://interiordesignassist.wordpress.com/2015/07/27/painting-white-1/

27 PAINTING WHITE – 2

https://interiordesignassist.wordpress.com/2015/07/29/painting-white-2/

28 BLACK Part – 1

https://interiordesignassist.wordpress.com/2015/08/07/black-part-i/

29 COLOURANTS DYES and PIGMENTS

https://interiordesignassist.wordpress.com/2014/07/15/colourants-dyes-and-pigments/

30 RED Colours of ancient times

https://interiordesignassist.wordpress.com/2015/05/22/red-colours-of-ancient-times/

31 ART COATINGS

https://interiordesignassist.wordpress.com/2015/05/25/art-coatings/

32 PRIMITIVE COATINGS # 1

https://interiordesignassist.wordpress.com/2015/05/03/primitive-coatings-1/

33 NATURAL IRON OXIDE PIGMENTS 4 # SIENNA and UMBER

https://interiordesignassist.wordpress.com/2015/05/01/natural-iron-oxide-pigments-4-sienna-and-umber/

34 NATURAL IRON OXIDE PIGMENTS -3 # Ochers

https://interiordesignassist.wordpress.com/2015/04/28/natural-iron-oxide-pigments-3-ochers/

35 NATURAL IRON OXIDE PIGMENTS – 2 # Red Oxides

https://interiordesignassist.wordpress.com/2015/04/27/natural-iron-oxide-pigments-2-red-oxides/

36 FLOOR PAINTS

https://interiordesignassist.wordpress.com/2015/03/21/floor-paints/

37 ARCHITECTURAL COATINGS -beginnings of OIL PAINTS

https://interiordesignassist.wordpress.com/2015/02/15/architectural-coatings-beginnings-of-oil-paints/

38 SURFACE PREPARATIONS

https://interiordesignassist.wordpress.com/2014/09/26/surface-preparations/

39 WHITE PIGMENTS

https://interiordesignassist.wordpress.com/2014/08/05/white-pigments/

40 CEMENT PAINTS

https://interiordesignassist.wordpress.com/2014/07/09/cement-paints/

41 OIL BOUND DISTEMPERS -OBD

https://interiordesignassist.wordpress.com/2014/07/03/oil-bound-distempers-obd/

42 CEMENT FINISHES part 2

https://interiordesignassist.wordpress.com/2014/06/27/cement-finishes-part-2/

43 DRY DISTEMPER or CALCIMINE

https://interiordesignassist.wordpress.com/2014/06/03/dry-distemper-or-calcimine/

44 ECOLOGY and COATINGS

https://interiordesignassist.wordpress.com/2015/03/09/ecology-and-coatings/

45 ENCAUSTIC PAINTING

https://interiordesignassist.wordpress.com/2014/06/06/encaustic-painting/

46 COLOURS and BUILDINGS

https://interiordesignassist.wordpress.com/2015/01/20/colours-and-buildings/

47 GLOSS

https://interiordesignassist.wordpress.com/2014/09/20/gloss/

48 COMPOSITION of COATING

https://interiordesignassist.wordpress.com/2014/07/29/composition-of-a-coating-3/

49 COLOURED GLASS

https://interiordesignassist.wordpress.com/2014/08/03/coloured-glass/

50 GRISAILLE -monochrome form of presentation

https://interiordesignassist.wordpress.com/2014/07/28/grisaille-monochrome-form-of-presentation/

51 WATER COLOURS

https://interiordesignassist.wordpress.com/2014/07/10/water-colours/

52 FRESCO PAINTINGS

https://interiordesignassist.wordpress.com/2014/06/24/fresco-paintings/

53 PRIMER COATINGS

https://interiordesignassist.wordpress.com/2015/06/07/primer-coatings/

54 SINGLE or MULTI COAT SYSTEMS

https://interiordesignassist.wordpress.com/2015/05/30/single-or-multi-coat-systems/

55 BRUSHES

https://interiordesignassist.wordpress.com/2015/03/29/brushes/

56 ENAMELS

https://interiordesignassist.wordpress.com/2015/02/18/enamels/

57 TEMPERA

https://interiordesignassist.wordpress.com/2015/01/24/tempera/

58 GP -General purpose paints

https://interiordesignassist.wordpress.com/2014/08/26/gp-general-purpose-paints/

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UNDERSTANDING LACQUERS

Post 498 –by Gautam Shah

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Cosmetic Box

In early 1920 Lacquers were considered industrial coatings, mainly used by White-goods and Automotive industry. Earlier to this period a Lac or Shellac coatings were wood craft finishing techniques and material. Industrial age lacquers were favoured due to their fast drying and non-yellowing properties. Clear Lacquers were increasingly replacing tin as MS sheet coating for food packing but were found suitable for aluminium sheets packing such as collapsible tubes and canisters. Lacquers were also used for the nail polishes and as hair fixing sprays. These lacquers as the name suggests were not made of natural Lac or shellac but from Nitro Cellulose. The lacquers needed thinners of various types for different application technologies and seasons.

Lacquer Paint Pic from Wikipedia by Author Victorgrigas

Oil paints based on Alkyd resins or GP Enamels need thinner of single solvent material such as Genuine turpentine, Mineral turpentine and in few instance Naphtha or superior grades of kerosene would work. These solvents singly can work for all application needs and for cleaning-washing post-painting work. With alkyd-based paints, a resin is the film-forming component. It is reduced in viscosity during the manufacturing and later during application. The requirements of solvent-s differ according to ‘length of the resin’ (which designates the proportion of oil versus other modifying-polymerizing agents, such as typically a phthalic anhydride). Short-oil length resins may require stronger solvents. A solvent that dilutes the viscosity alone may not achieve application level of viscosity. Some type carrier or diluent solvents are required which acting as a ‘carrier’ material help achieves application level (such as spraying) viscosity. The carrier solvents evaporate fast before the chain linking (and so film forming-drying) process starts at ambient temperature, raised or baking temperature or through a catalyst enabled reaction.

Wood Brushing Lacquer Pic from Wikipedia Pic by Author Mk2010

The word Lacquer has become a misnomer. A Lacquer in nominal usage means a coating system that is fast drying, tougher and non-yellowing. All lacquers, however, are not NC (nitro-cellulose) lacquers. Other Lacquer coating systems formulations are based on Acrylic resins, Amino resins, Urethane and epoxy systems. NC lacquer dries with evaporation of solvents, at ambient temperature or often in warm chambers. Other formulations require baking-stoving environments or have two-pack system (a catalyst and paint mixed just before application). A NC lacquer film can be wetted-dissolved after drying (such as Nail-polishes of pre 1965 era) by a thinner, and are called ‘non-convertible systems’ (product that does not get chemically converted into something else). But newer generation-lacquers cannot be dissolved or removed easily after drying, and are called ‘convertible systems’ (product that gets chemically converted into something different).

Box Lacquered

Lacquer Nail Polish Pic through Wikipedia -Source http://www.flickr.com/photos/zitona/4733601645/ by Author » Zitona «

All types of Lacquers, convertible or non-convertible products require very specific type of thinner. A company that formulates the paint system, for reasons of Patent knowledge, may not reveal the exact formulation. So it is very necessary to use the thinner specified by the manufacturer. A thinner is a combination of different solvents. There are two important considerations, action of dissolving and diluting (acting as a carrier), and evaporation rates of the solvents. A Lacquer system may need as much as 75% or more thinners for spray like application. But after the deposition on the surface, it does not require such low viscosity. So some solvents (usually diluent or carrier) begin to evaporate very quickly. Some other slower evaporating solvents, allow time for film to level out.

640px-Hair-Spray-Painting-6415.jpg

Lacquer coated Brass

A lacquer-thinner is a combination of solvents of basic Five groups. First group consists of latent solvents like Toluene, xylene and naphtha. The other three groups are of active solvents such as, ketones, esters, glycol ethers. Alcohol, though a latent solvent, in combination with other solvents plays an active role.

Lacquer thinners are affected by the weather and process of application. A normal thinner works for average temperature-moisture conditions. For very wet, windy weather and for brushing or manual polishing with a cloth bundle, reduced the rate of evaporation achieved by adding or using a ‘retarder thinner’. For spray like application, an accelerated rate of drying is possible and for this accelerator or fast lacquer thinners are used. Spray applications require more and faster drying thinner compared to wood lacquers that require less and slow drying thinner.

Channapatna-toys

1280px-Sankheda_furnitureChairs_of_3_piece_set

Shellac finishes were the first true clear coatings. Shellac is an insect exudate known as stick lac. Stick-Lac is refined to remove impurities and lighten its colour. Button-Lac is a manually purified is of darker colour, while machine purified shellac is often dewaxed and de-colourized. Shellac is soluble in methylated spirit or alcohols. Sankheda furniture and Chinese lacquer items are examples of shellac coatings. Shellac is a very effective coating material even in very thin viscosity, as a result its penetration and filling capacity is excellent. It is eminently recoatable so a very level and glossy surface is possible.

640px-Burmese_lacquerware.JPG

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LACQUERS or NC LACQUERS

Postby Gautam Shah

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640px-Fender_Marcus_Miller_Jazz_Bass_(Japan)_autographed_by_Marcus_Miller_-_bolt_on_neck_joint_plate

Lacquer is a very generic term applied to a variety of coating systems. It indicates a surfacing system, where a film forming substance has been dissolved in or diluted with a solvent. On application the solvent evaporates leaving a thin film on the surface.

The lacquer, on evaporation of its solvents changes the phase from Liquid to Solid, but does not convert itself into different substance. Lacquer films are soluble in the (original) solvent. Lacquers are also thermoplastic (will soften with an increase in heat) materials. The film forming substances of lacquers are linear polymers high in polymer weight with good solvent releasing property. Such substances are often very hard and brittle, so require addition of plasticizers to achieve better adhesion, flexibility and durability of the gloss.

State_Gifts_Lacquer_Bowls

Commercially the term Lacquer is applied to Solvent-based Coating systems (against water-based systems) that offer hard, glossy and durable film. In this sense, there are Two basic varieties:

1 Thermoplastics type: Nitro cellulose, Acrylics, Chlorinated Rubber, Vinyls, Epoxy.

2 Thermosetting type: Acrylics, Epoxy Resins, Polyurethanes, Vinyls, Alkyd, Melamine.

bottle-brush-close-to-755993

Cellulosic Polymers

Cellulose is the most widely occurring, a natural polymer, available in almost all plants. Primary sources of industrial cellulose are cotton fibres and wood. Cellulose is a polyhydric-alcohol, and forms esters with organic acids. It also forms reaction products with inorganic acids. These cellulosic derivatives used in production of various types of lacquers are classified as:

1. esters of inorganic acids -nitro cellulose

2. esters of organic acids -cellulose acetate

3. others -methyl and ethyl cellulose

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Lacquers can be classified into two basic groups:

NC Lacquers and Acrylic or Plastic Lacquers.

Lamellar Lines Mudguard Horizontal Lacquered Sheet

Nitro Cellulose Lacquers

NC Lacquers consist of Nitro cellulose as the main raw material to which a variety of plasticizer and resins are added, to provide wide range of film properties. PLASTICIZERS increase elasticity and extensibility of the film. Commonly used Plasticizers are, blown-castor oil, dibutyl phthalate, dioctyl phthalate, dibutyl sebacate, butyl stearate, chlorinated diphenyls. Additions of RESINS increase gloss and adhesion of the film. The resins are coconut and castor oil alkyds, maleic modified ester gum, cyclohexanone (ketonic) resins, acrylic resins, toluene sulfonamides formaldehyde resins.

Lacquered_secretaire,_Residenzmuseum,_2017-09-13

NC Lacquers are produced by dissolving or diluting lacquer and suitable plasticizers in a mix of solvents. The SOLVENTS act in three ways: Active solvents are (ethyl acetate, butyl acetate), Latent solvents (ethyl alcohol, butyl alcohol, diacetone alcohol), and Dilutents (toluene, xylene). A suitable mix of these basic three types of solvents is known as `Thinner‘. A very specific quality of Thinner is required for each application and weather condition.

NC Lacquers do not become yellow with ageing. It has no peeling problem. Lacquers provide very ‘water-white’ (no colouration or tinge) film. NC Lacquers are re-coatable and removable substances.

NC Lacquers are used on wood, metals, metals like gold, silver and copper, plastics, leather, paper, fabrics, as hair-fixers, and Nail-polishes. Lacquer is one of the best surface sealing material for wood products and so forms the primer coat for melamine, etc. 

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Solvent-based nitrocellulose lacquers (from resin of nitration of cotton (lint) and other cellulose based materials, were used commercially from the 19th C. These lacquers began to replace shellac lacquer and were used as protective or rust inhibitive clear coatings for brass musical instruments, gift items and furniture. These were also used in white-goods products (refrigerators, irons, cooking tops, etc. and in automobiles. These lasted for several decades till arrival of ‘Polymer based lacquers‘.

These materials are called Lacquers because the film is ‘water-white’. Acrylic lacquers of thermoplastic type are characterized by a transparent water white film, very good resistance to decolouration from temperature and UV light, good electrical properties, outdoor durability, excellent resistance to mineral oil-greases, resistance to chemical fumes, resistance to water based alkaline substances.

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Acrylic lacquers convertible coating that is on drying covert to a different product, which is non-dissoluble and non-removable. These are used for: wood items, clear coating for brass, copper, and aluminium, as a top coat for final gloss and protection air-crafts, automobiles, toys, auto-parts, industrial components, consumer durables, TV cabinets. These are used as clear-invisible coating for exposed surfaces like bricks, stones and concrete. Acrylic lacquers with soluble dyes form transparent glass coatings. One of the major uses is for internal coatings of food and beverage cans.

Thermosetting Acrylics provide a hard and scratch proof coating, good colour retention, better water and detergent resistance, better gloss and chalking resistance.

640px-Grete_Jalk_-_GJ_table

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