VOCs Generic Document

[ 6 ]

Introduction and summary

Volatile Organic Compounds (VOC) - everyone is aware of them. Solvents are substances that evaporate easily and which dissolve other substances. You may say this “Sounds Logical, this is why they are called ‘solvents’”. This is indeed true, and precisely because of their high measure of evapora-tion and fat-dissolving power they continue to be commonly used in paints, lacquers, glues, cleaning and degreasing liquids. Toluene, acetone, “tri” and “per” (hydro chloro carbons), thinner and isopropyl alcohol (IPA) are known examples.Solvents are without a doubt the best way to clean something in record time. They are unfortunately also extremely bad for your health.Nowadays we have reconsidered solvent use. Everyone has heard that sol-vents are a danger to people and the environment. What are these dangers exactly?Solvents have (neuro) toxic properties. Once in the body they may damage the nervous system. The brain is the most susceptible to solvents.Knowing these facts it is hard to imagine that things were done very differently in the past. There are still many printers that can tell horror stories about the topic. How could it be that people used to work under such conditions? The answer is easy: people didn’t know any better.Luckily, nowadays we do know better. This is why our business sector is ta-king the responsibility to reduce the use of solvents as much as possible.

1. What are solvents

A Volatiles Organic Compound (VOC) is “all organic compound which has a vapor pressure of 0,01 kPa or more, at 293,15 ºK, or which has an equivalent volatility the particular using conditions”.

The term “VOC” involves a big variety of chemistry compounds, including aliphatic hydrocarbons, aromatics and chlorinated hydrocarbons; aldehydes, ketones, ethers, acids and alcohols.According to the information from ESIG (European Solvents Industry Group), the European association of solvent producers, even a fourth part of the vola-tile organic compounds which are emitted to the atmosphere comes from the use of solvents. The rest of VOCs emitted comes from human origin (trans-port and electric energy produced by combustion), vegetation and animals.The VOCs could have different direct or indirect effects over human health and environment.

Environmental issues

The VOCs could have different direct or indirect effects over environment, where the main effects are producing photochemical oxidants by means of reactions caused by the sun light in presence of nitrogen oxides.

The main VOCs environmental problem is their contribution to producing photochemical smog at big cities with high levels of atmospheric pollution. The VOCs react with atmospheric pollutants which are in the city air (nitrogen oxides, produced by the traffic and heat systems, mainly) and in the presen-ce of the sun light could produce ozone. So, the VOCs and nitrogen oxides are known as precursory pollutants of ozone.

Health and safety issues

What are the actual effects of exposure to overly high concentrations of solvents?

People react to exposure differently depending on the duration and method of exposure. Let us examine the effects:

[ 7 ]

Short term effects

One possible short term effect is irritation of the airways. In addition, many solvents are neurotoxic. This means they may cause dizziness and the sen-sation of being ‘high’ at high levels of exposure. At very high levels nausea and loss of consciousness may follow. The “Tri” of olden days (Chloroform) was a well known example. The symptoms often disappeared rapidly once the source of exposure was taken away

Long term effects

Lasting effects may result from repeated overexpose due to the solvent’s neurotoxicity. One of these is OPS (Organic Psycho Syndrome), also known as the painter’s disease or Chronic Toxic Encephalopathy (CTE). Worrisome symptoms such a memory loss, change of personality, chronic fatigue en early onset dementia can occur. OPS is irreversible!

Regarding Printing Industry, data for more recent years indicate a reduction of the number of registered cases, thanks mainly to better information for workers exposed to solvents, and above all to better ventilation in workshops.

There are also solvents that may be cancerous, mutagenic (leading to birth defects) or hazardous to reproduction. This should obviously be indicated clearly in the accompanying Safety Information Sheets (SIS, Dutch: VIB). We recommend that you collect and register current en complete SIS’s for all of your solvents. If in doubt, contact your supplier. They are obligated to supply the desired information.

These are not the only dangers solvents pose. Please consider the fire ha-zard or the environment of our surroundings as well. Solvents contribute to smog, acid rain and global warming. Enough reasons the restrict their use.

2. The CORE INFO about solvent use in the offset

Offset is one of the most-occurring printing technologies within the business sector: around 80% of companies use this technology. Given this significant number this technology is an obvious target for reduction in our sector not just for social partners but for the government as well. For additional informa-tion on the offset we refer you to the Technical Appendixes.

Offset is also a print technique which to this day continues to use Volatile Organic Compounds (VOCs). While it is true that there is also solvent-use in pre-press (filmcleaners, glasscleaners, (cleaning spirits) the quantities in use there are minor compared to the amounts using in printing. With the arrival of Computer to Plate (CtP) use of solvents in pre-press has become a thing of the past.

It is not clear to people outside our industry exactly where this solvent use is taking place in the printing process. Commonly suspected use of ‘solvent containing inks’ is not the case. Only the mineral oils (with a flash point of far above 100°C) are ‘solvents’ that can still be found in paste inks. Even these

[ 8 ]

are found less and less due to the rapid adaptation of vegetable ‘bio-inks’ (in the context of Corporate Social Responsibility, CSR).

The places that VOCs occur lie outside the print procedure. Specifically, the following two types of solvents are relevant:

• Isopropyl alcohol (IPA) that is used as damping solution additive

• Washing agent for cleaning the printing press

The use of IPA in offset printing is the predominant culprit for solvent use: as such the BATsGRAPH project has chosen to place its focus there. As BATsGRAPH, we can conclude that it is wise for printing companies to face the IPA issue in a step by step manner. The likelihood of achieving VOCs re-duction successfully is highest when a company does not strive for complete resolution in one step but though introducing the BATs step by step.

During the countrywide evaluation we were able to conclude during the BATsGRAPH project that many Dutch printing companies have been able to achieve good reductions in IPA use. In fact, many printing companies have been able to reduce the IPA concentration in the damping solution from a conventional 10 to 12 % (by volume) to 8 or even 5%. There are even printing companies that have completely eliminated the use of IPA. This is a good example of a source-based approach. A number of effective chances made by Dutch printing companies has reduced the total use of IPA from 2.300 tons in 1996 to 1.000 tons in 2009. We can conclude that IPA reduction is indeed possible and that use of the BATs will lead to an overall reduction in the use of IPA in other EU countries.

As stated, the reduction of IPA will not happen by itself. Many companies encounter technical difficulties in their attempt to achieve IPA reduction; as a

result, they postpone further IPA-reduction. As business sector we consider this a missed opportunity as foregoing IPA also confers many benefits. One of these is the delivery of better-looking printing product at a lower cost (IPA influences the inks due to its VOCs effects). Another benefit is the creation of a better ink moisture balance which allows on to be ‘on color’ more rapi-dly. A further benefit is that the Safety & Health criteria for ventilation in the printing location become less strict when there is no or reduced IPA use in the damping solution. Finally, the printing company also shows active invol-vement in the areas of environmental care and environmentally responsible entrepreneurship.

The use of cleaning agents in less quantity and/or based on vegetable oils is promoted by BATsGRAPH but it´s not specifically on the scope of these Best Practices because they don´t produce any significante technical problem du-ring its implementation.

Regarding to the use of Vegetable Inks we can state that they are a sustai-nable alternative Mineral Inks, although they don´t produce VOCs in Sheet Fed production and they are nowadays available for printers because the ink manufacturers have improve them to the printing conditions. However, the main problem which is reducing the effective implementation of these inks is the lack of control over the printing parameters. Then, the change from mi-neral oils inks to vegetable oils inks could reduce the quality and productivity of the printing process.

3. Succesful implementation needs BATs integration

The implementation of Replacement of IPA, Optimizing of IPA and Ceramic, metal and hydrophilic distributing and plate rollers needs an integrated appro-ach because all of them are related with the damping solution. It’s not useful

[ 9 ]

to give recommendations for each BAT so the Consortium decided to deve-lop a common document about IPA REDUCTION IN OFFSET PRINTING.

At the same time, the quality result when printing with Vegetable Oils Inks is depending on the dampening solution conditions.

So, in addition to the technical clues to reduce VOCs it´s very important to integrate all the BATs and to control the printing parameters.