Plastic - the sustainable designers quick guide

In the sustainable quick guide to plastics we'll look at the various types of plastic, the uses, identification codes and recyclability and at the end there is a brief summary of Bioplastics.

Most plastics can be recycled however there are a number of barriers to recycling.
During the recycling process the various types of plastics need to be separated, this is where clear marking and not mixing multiple types of plastic in one product are very important.
The other main barrier is getting the end-user to sort the waste into recycle bins and to have recycling facilities available to accept and process the waste.
In most countries plastic recycling rates are still very low, the best systems still only recycle 27% of all plastics.

Plastic Types:

PET - Polyethylene terephthalate
Used for: Drinks bottles, food jars, sauce bottles
Properties: Clear, strong, water and gas resistant
Recyclable: Most popular type of plastic to recycle, many countries have a good system to recycle PET plastic

PE-HD (HDPE) - High-density polyethylene
Used for: Drinks bottles, liquid soap, cleaning products, household buckets
Properties: Slightly opaque, stiff, strong, water resistant
Recyclable: Very popular type of plastic to recycle, many countries have a good system to recycle HDPE plastic

PVC - Polyvinyl chloride
Used for: Blister or clam packs, cling films (non-food grade), water pipes
Properties: Strong, tough, water resistant, versatile, easy to glue or heat seal
Recyclable: PVC is not as commonly recycled as type 01 or 02 plastics. In many places this is disposed of in landfills.

PE-LD (LDPE) - Low-density polyethylene
Used for: Food bags, squeezy bottles, food films, flexible containers
Properties: Flexible, water resistant, easy to heat seal, tough
Recyclable: Wrappers and bags are not usually removed from the waste stream.  Films and bags are less likely to have the recycle logo on it.

PP - Polypropylene
Used for: Yogurt & Margarine tubs, take-away containers
Properties: Strong, moderately flexible; heat, oil and water resistant
Recyclable: Depending on the size of the products, PP plastic may not be easily isolated and recycled.

PS - Polystyrene
Uses: Take-away containers, thin plastic food containers (eggs), party cups
Properties: Clear, easy to mold, thin wall thickness
Recyclable: Depending on the size of the products, PS plastic may not be easily isolated and recycled.

EPS - Expanded Polystyrene

Uses: Insulated containers, cold storage boxes, packaging

Properties: Lightweight, easy to mold, thermal barrier, shock absorption 

Recyclable: EPS is 98% air and can be reused into other products or broken down into General Purpose Polystyrene (GPPS) pellets.  EPS is not as commonly recycled as type 01 or 02 plastics. 

O - Other
Polycarbonate, ABS plastic and other combination of polymers.
Polycarbonate is used for clear, hardwearing items such as glass replacements in lenses and lamps.
Recyclable: Due to the mixture of compounds these plastic types are hard to recycle and are not generally recycled.

Bioplastics
Bioplastics are derived from plant-based oils rather than petroleum-based. Some bioplastics are biodegradable but not all.
The most popular bioplastic is starch-based.  These can use a number of renewable plants/vegetables for the basic manufacturing materials.
Polylactic acid (PLA) is a transparent plastic produced from cane sugar or glucose. It is very similar in to PE or PP.  This has given rise to problems in the recycling of PE and PP plastics as they will be contaminated if PLA is introduced into the waste stream.

The sustainable graphic design blog will cover Bioplastics in more depth in another article.

If you're interested in sustainable options, check out the sustainable graphic design quick guides here.

Glue - the sustainable designers quick guide

The sustainable designers quick guide to glue and adhesives.
There are a huge variety of adhesives and glues available, in this guide we'll concentrate on the most commonly used glues for paper and packaging and hopefully it will be a springboard for your own investigation into the glues you'll consider using. Check out the sustainable adhesive options at the bottom and the introduction to no-glue alternatives.

Essentially we can subdivide glues into synthetic and naturally derived, and into reactive and non-reactive. For more details of the history and different properties of glues check this link.

The main environmental impacts from glues are the:

• solvent and gas emissions derived from the production and curing process 
• biodegradability of the disposed product 
• renewability of the material the glue was manufactured from

PVA glue
PVA is a white glue which is an emulsion of polyvinyl acetate in water.  This synthetic polymer sticks porous materials like paper and wood as the water evaporates leaving behind the PVA polymer. It forms transparent films that are resistant to organic solvents, oil and grease and impermeable to most natural gases. PVA can be made a neutral pH to increase the lifespan of books and papers. PVA is nontoxic to humans however it does release toxic fumes if burned. PVA is biodegradable.  PVA glue is a synthetic polymer manufactured from products generated by the petrochemical industry.

Synthetic Resin glue (one part epoxy)
Clear glue in a tube that has a strong solvent smell (ie. Multipurpose, UHU or GOOP) you don't have to mix it with anything. You may find them marketed as different products to bond different materials however they are all essentially the same although some may be thinner for precise application, thicker for non-drip/vertical application, or with added UV resistance and added colour.
They bond to metals, glass, some rubber and plastics, ceramics, paper, wood, leather, vinyl, canvas, masonry, concrete. They dry clear and are waterproof, acid free and slightly flexible.
Synthetic Resin glues give off solvents as they are curing and are irritating to eyes and skin. These glues are toxic to aquatic organisms and may cause long-term adverse effects in the aquatic environment. All of these products are made from petrochemicals.

Two-part epoxy glue
These glues require two parts to be mixed together, an epoxide resin and a hardener.
They can be used on paper, card, wood, metal, glass, stone, and some plastics. Epoxy adhesives are better in heat and chemical resistance than other common adhesives.
They can be made flexible or rigid, transparent or coloured, and have various setting times.
The main hazard is allergic reaction to the hardener and can cause occupational asthma.  Some chemical compounds in the epoxy resin can cause cancer and developmental disorders in animals and humans as they are endocrine disruptors.
Almost all of these products are made from petrochemicals however some manufacturers have made epoxy that includes natural wood resins.
http://star-distributing.com/shopsite_sc/store/html/page6.html

Latex-based glue (rubber cement and contact adhesive)
Latex-based adhesives are used to glue fabric, carpets and flexible porous objects. They can also be used as removable adhesives on non-porous surfaces.  Latex glues are formed from natural latex (rubber trees) or synthetic latex. They are mixed in a solvent to keep them fluid, this is generally acetone, hexane or heptane.  There is also a type of latex-based glue that is water-based (Copydex in the UK). These solvents evaporate leaving behind the rubber.
Latex-based glues do not work well in very cold conditions and can cause discolouration to light fabrics and paper. Natural latex glue is generally not as durable as other adhesives however it is very flexible. Natural latex is biodegradable and is naturally resistant to mold, mildew and bacteria.   Some people have an allergic reaction to natural latex.  Synthetic latex is created from oil-derivatives of the petrochemical industry, it forms a stronger bond and is hypoallergenic.
The solvents in these glues are produced from the petrochemical industry and can be hazardous if inhaled, they are also highly flammable. These solvents can damage some plastics and other polished surfaces.

Superglue
Superglue, cyanoacrylate or CA glue is a fast bonding adhesive that forms strong but brittle bonds.  It bonds skin and other organic and porous materials very well and is water resistant.   These glues contain solvents such as methyl alcohol to keep them in a liquid form. The fumes can irritate eyes, nose and throat and skin. CA glue is made from formaldehyde plus products from the petrochemical industry.

PVC plastic cement
PVC plastic cement is used to bond PVC plastic together.  It doesn't bond any other type of material or plastic. Essentially it provides a chemical weld between the two PVC plastic surfaces.  This works because the cement is actually a solvent that dissolves the PVC surfaces that it is in contact with. As the solvent evaporates the PVC plastic hardens and both surfaces are bonded together. The main hazard is inhalation of the vapour as it evaporates. The solvent is a product of the petrochemical industry.

Animal-based glue
Animal product based glue or horse glue is not commonly used except for speciality trades such as musical instrument repair and traditional cabinet carpentry. It is brittle and requires heating before application. It is biodegradable and from a renewable source.

Heat-seal adhesives
Another alternative to "cold glue" is heat-seal adhesives.  These are thermoplastics that are coated onto the surfaces and then activated by heat and pressure.  These adhesives don't change chemically but bond together due to heat.  Heat-seal adhesives can be solvent or water-based that are applied as liquid coatings. Some heat-sealing adhesives can also be applied as a hot melt coating via gravure, slotted die, or extrusion processes. The heat-seal process can be run on high speed production lines and is common for packaging.  An example of a heat-seal adhesive is Vinyl Acetate Acrylic Copolymer in a water based solution - a product of the petrochemical industry.

Sustainable Adhesive Options
The most sustainable options for adhesives involve using water-based emulsions or aqueous, latex-based or starch-based glues.  These are usually solvent-free alternatives. Solvent-less adhesives have been shown to emit 75% less CO2 and use 80% less energy than solvent-based adhesives.
Various adhesive manufacturers make sustainable options for both cold-seal and heat-seal adhesives.

No Glue Alternatives
The most ecological and sustainable designs are those that use no glue at all!  There is a lot of great design work happening for packaging that redesigns the need for glue. When was the last time you found your pizza box was glued together? This also saves on production costs.  Stay tuned to this blog for examples of designs that have out-designed the glue!


If you're interested in the sustainable options for paper, recycled paper or ink then check out the other quick guides in this series.

Inks - the sustainable designers quick guide

In this quick guide to inks we'll cover the toxic and environmental impacts of inks and the various alternatives available. At the end there's a quick summary of inks that don't deink - important information that may change your choice of printing!

Traditionally inks used in the professional printing industry have been petroleum-based.  These were introduced in the 1960's as they dried a lot quicker than vegetable-based inks. These petroleum-based inks enabled printers to run jobs faster and increase overall productivity.

Three main environmental issues with petroleum-based ink are:

• Volatile organic compounds
• Heavy metals
• Non-renewable oils

Volatile organic compounds or VOCs  - enable the ink to dry very quickly.  Many VOCs are dangerous to human health or cause harm to the environment. Due to these hazards VOC exposure is regulated in the workplace.  Inks do not necessarily give off their entire VOC content. In lithographic inks, very little of the ink oil used actually evaporates. Petroleum-based inks contain 30-35 percent VOCs.

Heavy Metals - are found in the pigments of some inks. Barium, copper and zinc can be found in some pigments. They are most often found in metallic inks that are green, orange or opaque yellow. Heavy metals are toxic and sometimes carcinogenic and do not biodegrade.  Instead they can leach into soil and groundwater from landfill sites and cause major problems to rivers and groundwater supplies.

Non-renewable oils
Petroleum-based inks are based on a non-renewable resource.  We can't grow more petroleum or crude oil. Check the sustainable graphic design blog from more information on the impacts of oil use and the phenomenon of peak oil. All good reasons to reduce our reliance on petroleum-based products.

Vegetable-based inks
Both soy and vegetable inks are made from renewable plant material and can help reduce VOC emissions. Soybean oil-based inks range from 2-5 percent VOC. One major problem with soy ink is that it takes more time to dry than petroleum-based inks, due to its lack of evaporative solvents in the form of VOCs.
The term "soy-ink" does not necessarily mean that the ink is 100% soybean oil. In fact, inks may contain only minimal amounts of soybean oil and still be marketed as a "soy-ink".  Printing ink manufacturers in the US can use a SoySeal® logo with various percentages of soil depending on the type of ink. See here for the percentages of soy in the ink.
Here's a link to the SoySeal logo.

Soy ink is primarily used in lithographic printing processes, including newspapers, books and magazines. Coloured soy inks have penetrated the market at a faster rate than black soy inks. The reason being that petroleum is dark, while soybean oil is relatively clear in colour (see above photo of the really dark petroleum-based oil). This allows the pigment to be seen more readily and results in brighter colours. A more visible colour enables a given amount of soy ink to produce more impressions than the same amount of petroleum ink, which translates into a 5-50 percent increase in transfer efficiency.

Biodegradability 
Soy inks are more biodegradable than petroleum inks. As the percentage of soybean oil increases in an ink formulation, biodegradability increases.  The total amount of ink makes up less than 1% of the paper waste however the deinking process produces a sludge waste of about 20% of the paper mixture when paper fibre is recycled.

Price
Currently black soy inks are priced higher than petroleum inks. However in coloured inks, pigments are by far the most expensive component. Coloured soy inks are competitively priced with petroleum-based coloured inks.

Read more about biochemicals and in particular soy inks by downloading this pdf from pneac.org.

Soy What?
Here's a simple infographic from christineparkdesign.com representing the benefits of using soy-based inks - follow the link for the large version on her website.

Recycled Inks
These can lessen the environmental impact of printing. Inks are not recycled in the same way as paper, plastics or glass and can't be recycled once they have been printed. Some ink providers can reuse old or spent inks by blending them together to form other, usually darker colours or black ink.

Deinking
Deinking is the key process in paper recycling. Hydrophobic (water-repellent) ink particles are separated from hydrophilic (water-wettable) fibres. This process has been developed for offset and gravure inks which are roughly more than 95% of the current recovered paper mixture.
Current water based inks create problems as they cannot be removed in this process and accumulate in the system. Dyes and ink particles too small to be removed have no other exit than in the paper fibres. They stain them just as red socks make your white clothes go pink in the washing machine.

Check out the list below of inks that cause problems during the recycling of paper and don't de-ink!

Inks that cause problems and don't De-ink:

• Digital Prints
• Injet inks
• Flexo inks
• Indigo liquid toner 

To find out more about Deinking visit the International Association of the Deinking Industry at ingede.org
They also have the Deinkability scores here.

If you want to read more about the principles of ink check out paperrep.com.

For more Quick Guides for sustainable graphic design go to the quick guides page, or use the links in the top right hand column.

Recycled paper - the sustainable designers quick guide

The sustainable designers quick guide to  recycled paper. In the previous quick guide to paper there is information on virgin fibre paper, additives and coatings.  Here we'll focus on recycled paper.

According to the United States EPA production of recycled paper causes 35% less water pollution and 74% less air pollution than making virgin paper.
It also stops trees being cut down.  However due to the de-inking process it can result in waste sludge of around 20% by weight of the paper being recycled (check out the quick guide to ink for more info on de-inking).

Paper content

Recycled paper is made from either pre-consumer waste or post-consumer waste and may also include a percentage of virgin wood fibre.
Pre-consumer waste content is waste fibre from paper mills that never reached the consumer (cut offs, rejects, etc.)
Post-consumer waste content is the fibre that is made from recycled office and home waste.
*Post-consumer waste content is considered better than pre-consumer because it is more likely to end up in landfills if it is not reused.
- Grades of waste paper 
- Grades of pulp and paper

Brightness
Sometimes post-consumer waste recycled paper has slightly more small specks in the paper than virgin sheets. This is due to the recycling and de-inking process and the type of ink that was on the waste paper.
Recycled papers may be a point or two lower in brightness than their virgin paper counterparts. However, recycled papers generally have higher opacity (which means they are harder to see through), often considered an asset, especially for double-sided printing.
Designers can save on paper by using a thinner, less expensive sheet if it has more opacity. Using a thinner sheet can also save on mailing costs.
If your print job has 100% ink coverage then the slightly less bright recycled paper will not effect the finished product.

One of the factors that effects brightness is how paper is bleached. Here I'll go into the process in more detail and the various end-options that you can choose from when selecting paper.

Chlorine bleaching and Chlorine-free Paper
Chlorine bleaching is used to give paper its bright white colour. It can also have a negative effect on the environment. When chlorine is used to bleach paper the process can also result in the formation of harmful chemicals such as dioxins and furans, which are known to cause cancer in humans.
Other options for bleaching paper are available to the paper industry and these include oxygen bleaching. The safest paper bleaching processes are totally chlorine-free (TCF) or processed chlorine-free (PCF).

Here are brief explanations and some common logos (depending on where you live):

Totally chlorine-free (TCF): Virgin paper produced without chlorine or chlorine derivatives (the bleaching process uses oxygen-based compounds).

Processed chlorine-free (PCF): Contains recycled content produced without elemental chlorine or chlorine derivatives, although one or more fibre components may have originally been bleached with chlorine or chlorine derivatives. Any virgin pulp is TCF.

Elemental chlorine-free (Traditional ECF): Replaces elemental chlorine with chlorine dioxide in the bleaching process.

Enhanced ECF (ECF with extended or oxygen delignification): Removes more of the lignin from the wood before bleaching, thus reducing energy and chemical use during bleaching (the final stage uses chlorine dioxide).

Enhanced ECF with ozone or hydrogen peroxide: In addition to removing more of the lignin from the wood before bleaching, substitutes ozone or hydrogen peroxide for chlorine or chlorine dioxides as a brightening agent in the initial stages of the bleaching process (the final or near-final stage uses chlorine dioxide).

Which Chlorine Free Paper is best?
So on the basis of environmental criteria the best paper to get is:

1. PCF (because product includes recycled content)
2. TCF (TCF is used only to refer to 100 percent virgin paper)
3. Enhanced ECF with ozone or hydrogen peroxide
4. Enhanced ECF (ECF with extended or oxygen delignification)
5. Traditional ECF

To find out more about chlorine free products go to:
Natural Resources Defense Council
The Chlorine Free Products Association (CFPA)
Environmentally responsible printing

Sustainable forestry management
In addition to recycled paper there are also certifications that can be applied to paper obtained from sustainable forests.  The two main certification programs are:
PEFC Programme for the Endorsement of Forest Certification
FSC Forest Stewardship Council
Depending on which country you live in, there are various logos to signify sustainable forestry management.

Carbon Neutral Production
A product or company that have had their carbon dioxide and greenhouse gas emissions calculated, reduced and offset with credits from fund renewable, emission free energy products can be verified as carbon neutral.
Increasingly companies are becoming carbon neutral by buying credits from carbon offset schemes to become sustainable. Various standards and certification exist for different countries.  Here are a few common logos for carbon neutral products.

In addition to these varieties of recycled paper, there is also acid-free paper and the various additives (sizing) and coatings.  These are covered in the sustainable designers quick guide to paper.

Paper - the sustainable designers quick guide

The sustainable designers quick guide to paper. Here is a concise list of what's in paper and the coatings we use, and how sustainable it is. Use this guide as a starting point to make up your own mind about what paper and coatings to use.

Paper Facts:

• Paper is predominately made from wood fibre which comes from trees.
• 3 to 6 billion trees are cut down per year.
• The paper industry is the 4th largest emitter of greenhouse gases.
• About 35% of municipal solid waste (before recycling) by weight is paper and paper products.

There are two main paper making processes: 

• groundwood mechanical process (newsprint, telephone directories)
• kraft chemical pulping process (office copy paper, offset paper, cards) which is about half as efficient as the groundwood process (uses twice as many trees for same about of paper)

Coated "glossy" paper
Clay or chalk coatings are used in the kraft chemical process.  This is between 10-30% of the thickness of the paper. The clay gives it the glossy surface and is great to print on. Clay composts well.
Clay does not recycle well - it must be removed before paper is recycled. It can clog recycling machines however the clay does help to remove ink from paper fibres. Clay is obtained by open pit mining.

Paper additives
"Sizing" is added to make paper more water resistant.  Sizing can be starch, polymer or rosin. This is used in all paper but in large amounts in packaging and frozen food products.

Starch is also used to add stiffness and strength to paper.  It is obtained from starchy crops and the waste of some food crops. It composts well and can be easily removed during recycling.

Polymer is used to add "wet strength" this makes paper stronger even when it is wet. Photographic paper, filters, paper towels and food containers can all have added polymers. These compost slowly however due to their water repelling properties may add difficulty in the paper recycling process. Most of these polymers are manufactured from crude oil.

Acid free paper
Acid free paper is paper with a neutral pH.  Manufacturing acid free paper helps preserve the paper as acid rich paper goes yellow and breaks down over time.
The paper is usually treated with calcium bicarbonate to neutralise natural acids in the wood. Pine trees tend to be more acidic.
Most commercial paper is acid free.  This is the result of using chalk rather than china clay as the main filler. All sizing agents, inks and finishes should also be acid free.
Alkaline paper has a very long live expectancy, the manufacturing waste is more environmentally friendly and the paper is more easily recycled.

Brightness
Bleaching agents are used to increase the brightness and make paper whiter. Bleaching uses chemical agents such as hydrogen peroxide, sodium dithionite and chlorine. Conventional bleaching using elemental chlorine produces and releases into the environment large amounts of chlorinated organic compounds, including chlorinated dioxins which are toxic. Many modern manufactures use ECF (Elemental Chlorine Free) and TCF (Totally Chlorine Free) bleaching processes to reduce the release of chlorinated organic compounds.  Look for TCF if using virgin wood paper or PCF is the paper includes recycled content (check out the quick guide to recycled paper for more info).

UV coatings
These are applied over the ink and dried by exposure to UV light. They have a high gloss and can be applied to spot locations and in very thin films. They provide a strong UV protection to the underlying ink and provide water resistant properties.
UV coatings are usually made of acrylic polymers that are manufactured using highly toxic substances. Some UV coatings are made from soybean oil rather than crude oil. UV coatings are not easily recycled and in landfills they are not readily biodegradable.

Plastic lamination
Celloglaze is a super thin laminate film which is lightweight and flexible and is stuck to the paper using both heat and pressure. Celloglazing or plastic lamination can be matt or gloss and can be single sided or double sided. Celloglaze is not recyclable and not readily biodegradable.

Varnish
Varnish is a press coating - that means that during offset printing it is printed just like a process or spot colour. Varnish is basically ink without the pigment.  Like UV coatings these can be applied to spot locations. Varnish has the same effect on paper recycling as ink and can be handled by all paper recycling systems. Varnish does not work well on uncoated paper.

Aqueous coating
Aqueous coating is more environmentally friendly than UV coating because it is water based even though they are still generally made from acrylic polymers. Aqueous coatings do not seep into the press sheet as much as varnish and does not crack or scuff easily. Aqueous does, however, cost a lot more than varnish.
Aqueous coating is generally laid down in a single layer (like celloglaze) not to localised spot locations like varnish. Aqueous comes in gloss, dull, and satin.

Recycled paper

Recycled paper is made from either pre-consumer waste (waste fibre from paper mills that never reached the consumer) or post-consumer waste (the fibre that is made from recycled office and home waste).

Post-consumer waste content is considered better than pre-consumer because it is more likely to end up in landfills if it is not reused.

Check out the sustainable designers quick guide to recycled paper for more information.

Tree free paper
Tree free paper can be made from:

• Agricultural residue (sugar cane)
• Fiber crops (hemp, kenaf, jute, flax)
• Textile wastes (a small percentage)
• Wild plants (Sisal, bamboo)
• Specialist papers (elephant dung)

Tree free paper accounts for a very small amount of total paper production. Problems associated with tree free paper are that if it doesn't use crop byproducts it could lead to de-forestation of native rainforest just to grow these crops.

Multi-laminates
Multi-laminates are used for packaging and cartons and are also called aseptics, brick pack or tetra paks. They have a complex layer structure composed of plastic polymer (20%), aluminium foil (4%) and paper fibre (75%).  They are usually used for food packaging as they are water proof, strong and have a good shelf-life.  Due to the plastic polymers and foil they are not readily compostable.  Special equipment is needed to separate and recycle the fibre layers.  The paper layer in laminates is made from strong, high-quality virgin fibre. Because of this, tissue mills are the top customer for recovered laminates, since tissue must be made of strong fibre to meet necessary performance characteristics.

Waxed paper and cardboard
Waxed paper provides water repellant properties and is used for food and drink containers however due to problems with the wax affecting recycling plants these papers are generally not recycled.  Wax paper will compost well.


For additional information on paper packaging and sustainability download this 66 page pdf from www.greenblue.org

Check out the sustainable designers quick guide to recycled paper for more information about recycled paper, chlorine-free paper and sustainable forestry practices.

Stay tuned for the sustainable designers quick guide to ink & adhesives coming soon.