Leather is very well know to do be durable and flexible. It can come in any colour due to the die, however the most common colour and recognisable for leather is black and brown. There are many forms of leather including vegetable tanned, chrome tanned, rawhide, brain tanned, rose tanned, Alum-tawed, Synthetic-tanned and even more. Leather is normally oil and water resistant. Leather can also be quite cheap to work with in realtion to other materials.
Leather is usually from cattle skin however it can also come from lamb and deer, which has a much softer feel and because of this is more expensive. Leather can come from most animals that have skin or fur, from Kangaroos to Elephants.
The leather manufacturing process is divided into three fundamental sub-processes: preparatory stages, tanning, and crusting. All true leathers will undergo these sub-processes. A further sub-process, surface coating, can be added into the leather process sequence, but not all leathers receive surface treatment. Since many types of leather exist, it is difficult to create a list of operations that all leathers must undergo.
The preparatory stages are when the hide/skin is prepared for tanning. Preparatory stages may include: preservation, soaking, liming, unhairing, fleshing, splitting, reliming, deliming, bating, degreasing, frizing, bleaching, pickling, and depickling.
Tanning is the process which matches the protein of the raw hide or skin into a stable material which will not putrefy and is suitable for a wide variety of end applications. The principal difference between raw hides and tanned hides is that raw hides dry out to form a hard inflexible material that when re-wetted (or wetted back) putrefy, while tanned material dries out to a flexible form that does not become putrid when wetted back. Many different tanning methods and materials can be used; the choice is ultimately dependent on the end application of the leather. The most commonly used tanning material is chromium, which leaves the leather, once tanned, a pale blue color (due to the chromium); this product is commonly called “wet blue”. The hides once they have finished pickling will typically be between pH 2.8 and 3.2. At this point, the hides would be loaded in a drum and immersed in a float containing the tanning liquor. The hides are allowed to soak (while the drum slowly rotates about its axle) and the tanning liquor slowly penetrates through the full substance of the hide. Regular checks will be made to see the penetration by cutting the cross-section of a hide and observing the degree of penetration. Once an even degree of penetration exists, the pH of the float is slowly raised in a process called basification. This basification process fixes the tanning material to the leather and the more tanning material fixed, the higher the hydrothermal stability and increased shrinkage temperature resistance of the leather. The pH of the leather when chrome tanned would typically finish somewhere between 3.8 and 4.2.
Crusting is the process by which the hide/skin is thinned, retanned, and lubricated. Often a coloring operation is included in the crusting subprocess. The chemicals added during crusting must be fixed in place. The culmination of the crusting subprocess is the drying and softening operations. Crusting may include the following operations: wetting back, sammying, splitting, shaving, rechroming, neutralization, retanning, dyeing, fatliquoring, filling, stuffing, stripping, whitening, fixating, setting, drying, conditioning, milling, staking, and buffing. For some leathers, a surface coating is applied. Tanners refer to this as finishing. Finishing operations may include: oiling, brushing, padding, impregnation, buffing, spraying, roller coating, curtain coating, polishing, plating, embossing, ironing, ironing/combing (for hair-on), glazing, and tumbling.
Leather is a product with some environmental impact, most notably due to:
- the impact of livestock
- the use of chemicals in the tanning process (e.g. chromium, formic acid, mercury and solvents, …)
- air pollution due to the transformation process (hydrogen sulfide during dehairing and ammonia during deliming, solvent vapors).
- Leather biodegrades slowly; it takes 25–40 years to decompose. However, vinyl and petro-chemical derived materials will take 500 or more years to break down and return to the earth.
Mark Evans: Etched Leather Artwork
Modern leather-working tools
Leather Sample, not the textures
Tanned leather in Marrakech
- Clothing accessories (handbags, wallet)
- Car interiors
- Book covers
- American footballs
- Hot drink cup protection
- Eyewear glasses
- Wall Panels
Acrylic is a durable and strong polymer used as plastic in wide variety of applications. Acrylic sheets are usually used as substitute for glass due to its flexibility and other properties such as being lighter, easier to repair and more transparent. Acrylic is used to form wide range of shapes for wide array of products most especially in automotive applications and used as component in paints and resins.
Acrylic resins are used in a wide range of applications for the outstanding chemical characteristics and unique aesthetic properties. Currently, the strongest demand comes from automotive and medical device markets, and paints & coatings, adhesive & sealant and construction & architecture are the major application markets for acrylic resin.
Acrylic has good weathering properties, won’t fade quickly, so is Ok for outdoor use. It’s also non toxic and can be recycled.
Acrylic can be thermoformed. ie a flat sheet can be heated then mould into a shape, eg a bath tub.
All acrylics are constructed from petroleum distillates that are reacted to acrylic acid. This acid is reacted with alcohol in order for a monomer to be formed. PMMA or polymethyl methacrylate is the most common form of acrylic that is a polymerized form of methyl methacrylate. When it is catalyzed with organic peroxide, it will separate the double bond in methyl methacrylate molecule and it will join with another monomer which will form the polymer.
Acrylic is typically manufactured as lites, or sheets of different dimensions. It is called batch cell bulk polymerization wherein molds are formed by a couple of large planes that are made of steel or glass separated by flexible spacers. Into the mold is where the methyl methacrylate is injected with the catalyst in order for the acrylic to form into sheet. The thinner planes are being produced in the method of continuous bulk polymerization wherein the parallel metal bets are being utilized as the mold. The time needed to produce it is reduced by the belts that pass through zones of various temperatures to anneal the acrylic.
There are different acrylic goods which take their shape from the mold. Manufacturer of acrylics polymerizes the acrylic and pulverizes them into bulk powder. The bulk powder is then dispersed into the product manufacturer in accordance to their specifications. Acrylic will be formed into the product that is being subjected into heat. In most cases, the acrylic powder is mixed using a dyeing agent to make translucent acrylic.
Regardless of whether it is created from mold or sheet, acrylic will take its final form by getting finished by various processes. Compared to glass, acrylic can be sawed or drilled more easily, allowing it to be installed in different applications.
Chris Dorosz: Paint Drop Sculptures
Kartell – LCP Chaise Lounge | Home Design and Decor
Berlin Art Princess
Acrylic is a pritty flexible material for design, there are alot of variations, and alot can be done to it. Wether you want it transparent, flexable, solid or shiney. It can also be mixed with otehr materials easily.
- Sinks & Sinks
- Technical models
- Clock material
- Fascia panels
- Windows and skylights
- Lighting fixtures and lenses
- Motorcycle helmets visors
- Electric guitars
- Artificial fingernails
A beverage can is a metal container designed to hold a fixed portion of liquid such as a carbonated soft drinks, alcoholic beverages, fruit juices, teas, tisanes, energy drinks, etc. Beverage cans are made of aluminium (75% of worldwide production) or tin-plated steel (25% worldwide production). Worldwide production for all beverage cans is approximately 475 billion cans per year worldwide, 52 billion per year in Europe. This is ALOT of material that could be used or recycled.
Most metal beverage cans manufactured in the United States are made of aluminium, whereas in some parts of Europe and Asia approximately 55 percent are made of steel and 45 percent are aluminium alloy. Steel cans often have a top made of aluminium. The aluminium used in United States and Canada are alloys containing 92.5% to 97% aluminium, <5.5% magnesium, <1.6% manganese, <0.15% chromium and some trace amounts of iron, silicon and copper according to MSDS from aluminium producer Alcoa.
Beginning in the 1930s, after an established history of success with storing food, metal cans were used to store beverages. The first beer was available in cans beginning in 1935. Not long after that sodas with their higher acidity and somewhat higher pressures. The key development for storing beverages in cans was the interior liner, typically plastic or sometimes a waxy substance, that helped to keep the beverage’s flavor from being ruined by a chemical reaction with the metal. Another major factor for the timing was the end of Prohibition in the US at the end of 1933.
Various standard capacities are used throughout the world:
- In Australia the standard can size is 375 ml.
- In New Zealand the standard can size is 355 ml.
- In China the most common size is 330 ml.
- In most of Europe standard cans are 330 ml. In some European countries there is a second standard can size, 500 ml, often used for beer, cider and energy drinks.
- In the UK 440 ml is commonly used for lager.
- In India standard cans are 330 ml.
- In Japan the most common sizes are 350 ml and 500 ml. Larger and smaller cans are also sold.
- In Korea, 250 ml cans are the most common for soft drinks. However, when accompanying take out food (such as pizza or chicken), a short 245 ml can is standard. Recently, some 355 ml cans which are similar to North American cans are increasingly available, but limited mostly to Coca-Cola and Dr Pepper. Finally, beer cans also come in 500 ml forms.
- In both Malaysia and Singapore, the most commonly found cans are 300ml. Larger 330ml/350ml cans are limited to imported drinks where it would usually cost a lot more than local ones.
- In North America, the standard can size is 12 U.S. fl oz or 355 ml.
- In Canada, the standard size was previously 10 Imperial fluid ounces (284 ml), later redefined and labeled as 280 ml in around 1980. This size was commonly used with steel beverage cans in the 1970s and early 1980s. However, the U.S. standard 355ml can size was standardized in the 1980s and 1990s, upon the conversion from steel to aluminum.
- South African standard cans are 330 ml and the promotional size is 440 ml. A smaller 200 ml can is used for “mixers” such as tonic or soda water. It has a smaller diameter than the other cans.
- Fruit Juice
- Tinned food
Corrugated fiberboard is a paper-based material consisting of a fluted corrugated sheet and one or two flat linerboards. It is widely used in the manufacture of corrugated boxes and shipping containers.
The corrugated medium and linerboard are made of containerboard, a paper-like material usually over 0.01 inches (0.25 mm) thick. Corrugated fiberboard is sometimes called corrugated cardboard, although cardboard might be any heavy paper-pulp based board.
Corrugated (also called pleated) paper was patented in England in 1856, and used as a liner for tall hats, but corrugated boxboard was not patented and used as a shipping material until December 20, 1871. The patent was issued to Albert Jones of New York City for single-sided (single-face) corrugated board.Jones used the corrugated board for wrapping bottles and glass lantern chimneys. The first machine for producing large quantities of corrugated board was built in 1874 by G. Smyth, and in the same year Oliver Long improved upon Jones’ design by inventing corrugated board with liner sheets on both sides, thereby inventing corrugated board as it came to be known in modern times.
The Scottish-born Robert Gair invented the pre-cut paperboard box in 1890 – flat pieces manufactured in bulk that folded into boxes. Gair’s invention came about as a result of an accident: he was a Brooklyn printer and paper-bag maker during the 1870s, and one day, while he was printing an order of seed bags, a metal ruler normally used to crease bags shifted in position and cut them. Gair discovered that by cutting and creasing in one operation he could make prefabricated paperboard boxes. Applying this idea to corrugated boxboard was a straightforward development when the material became available in the early twentieth century.
The corrugated box was initially used for packaging glass and pottery containers. Later, in the mid-1950s, the case enabled fruit and produce to be brought from the farm to the retailer without bruising, improving the return to the producers and opening up export markets.
Where it comes from
Corrugated board is manufactured on large high-precision machinery lines called corrugators, usually running at about 500 feet per minute (2.5 m/s) or more. These machines, over time, have become very complex with the objective of avoiding some common problems in corrugated board production, such as warp and washboarding.
The key raw material in corrugating is paper, different grades for each layer making up the corrugated box. Due to supply chain and scale considerations, paper is produced in separate plants called paper mills. Most corrugating plants keep an inventory of paper reels.
In the classical corrugator, the paper is softened with high-pressure steam. After the board is formed it is dried in the so-called dry-end. Here the newly formed corrugated board is heated from the bottom by hot plates. On the top, various pressures are applied by a load system on the belt.
Old corrugated containers are an excellent source of fibre for recycling. They can be compressed and baled for cost effective transport. The baled boxes are put in a hydropulper, which is a large vat of warm water for cleaning and processing. The pulp slurry is then used to make new paper and fiber products.
Readily availible, fairly cheap, solid material. Easily painted, coloured cut, carved.
- Folding flat-pack chair
- Space Ship! (Good old toy!)
Old Computer / Tech Parts
Computer recycling or electronic recycling is the recycling or reuse of computers or other electronic devices. It includes both finding another use for materials (such as donation to charity), and having systems dismantled, in a manner that allows for the safe extraction of the constituent materials for reuse in other products.
Obsolete computers or other electronics are a valuable source for secondary raw materials, if treated properly; if not treated properly, they are a source of toxins and carcinogens. Rapid technology change, low initial cost, and planned obsolescence have resulted in a fast-growing surplus of computers or other electronic components around the globe. Technical solutions are available, but in most cases a legal framework, a collection system, logistics, and other services need to be implemented before applying a technical solution. The U.S. Environmental Protection Agency, estimates 30 to 40 million surplus PCs, classified as “hazardous household waste”, would be ready for end-of-life management in the next few years. The U.S. National Safety Council estimates that 75% of all personal computers ever sold are now surplus electronics.
Where it comes from
Export of waste to countries with lower environmental standards is a major computer or electronic recycling concern.
Metals like copper, aluminum, lead, gold, and palladium are recovered from computers, televisions and more.
Most electronic waste is sent to landfills or incinerated, which releases materials such as lead, mercury, or cadmium into the soil, groundwater, and atmosphere, thus having a negative impact on the environment.
- Landfill fodder