The versatility of water-based inks – history and future

Overview History of water-based printing inks Composition of water-based printing inks Application methods and product ranges Advantages of water-based printing inks Summary and conclusion

Overview History of water-based printing inks Composition of water-based printing inks Application methods and product ranges Advantages of water-based printing inks Summary and conclusion

History of water-based inks Evolution Applications 1890 Aniline printing inks (solvent) Wrapping paper 1938 First water-based printing inks on protein-based, natural resins Cardboard and industrial paper sacks 1950 Start of polymer chemistry: modified natural resins Cardboard and industrial paper sacks 1980 Start of acrylat chemistry: Resins and dispersions Cardboard and industrial paper sacks 1990 Wrapping paper, gift wraps, envelopes napkins, bakery bags, liquid food packaging, simple film printing Emission regulations: Increased demand for water-based inks! 2015 self-crosslinking systems/hybrid Quality film printing

Water-based inks today Current applications of water-based inks Flexography: Rotogravure: Image source: Follmann GmbH & Co. KG Image source: Doneck Network

Water-based inks tomorrow Food packaging Deep freeze Laminated packaging Corona Inline Hybrid systems Fine Anilox-Rollers PU-chemistry Doctor Blades Self-crosslinking dispersions Better drying conditions Technical machine parameters Ink formulation technology Image source: Doneck Network

Overview History of water-based printing inks Composition of water-based printing inks Application methods and product ranges Advantages of water-based printing inks Summary and conclusion

Composition of a water-based ink 2-8 % 30-50 % 10-30 % 5-15 % Additives Water Extender Binder Base Pigment

Pigments in water-based inks Carbon black Titaniumdioxide Organic – processed Magenta PR 57:1 Cyan PB15:3 Yellow PY 13 Lithol pigment Copper(II)phtalocyanine Azo pigment Image source: Flint Group The colourant of the printing ink is based on organic or inorganic pigments. The pigments are per definition insoluble in the medium in which they are used and they must therefore be dispersed in a ”carrier” (binder). Organic pigments can be of threee types: Pigmentary colours are pigments in their own right, being water insoluble compounds which happen because of their constitution to be coloured. These group represent the largest. Metal salt pigments are derived from coloured water soluble organic compounds, dyes, which have ben converted into insoluble salts. Lakes as used in the textile industry are similar to the metal salt pigments. The pigments can be classified into following types: The inorganic pigments used are primilary opaque white and carbon black. Fillers like calcium carbonate can be used as extender of inks. Due to the particle size, hardness of fillers and stability in the ink, especially with opaque white,the trend is to leave these out from the ink formulation. The degree of whiteness of the substrate will Have impact on the need for opaque white and fillers. The organic pigments represented by organic compounds of arylamides, azo, phtalocyanines etc. The organic pigments used are transparent or semi transparent and have various resistance properties based on their chemistry.

Components of water-based inks Binders Additives acrylic or styrene-acrylic copolymer PU + Hybrid emulsions Waxes Surfactants (wetting agents) Defoamers Retarders Biocides

Overview History of water-based printing inks Composition of water-based printing inks Application methods and product ranges Advantages of water-based printing inks Summary and conclusion

Application Methods Flexography Rotogravure Both printing technologies cover a broad variety of different application areas with specific ink series. Waterbased ink systems are processed mainly in the flexo and gravure. I would like at this point to point out that there are a variety of application areas for each procedure and to a wide variety of applications with an even greater number of ink series.

Product Range Flexography pre-print post-print Corrugated board Paper Tissue Film & Foil bakery bags paper bags newspapers Printing ink Substrate Impression cylinder Printing plate napkins table cloths kitchen towels toilette paper plastic bags flexible packaging Bildquelle: „Technik des Flexodrucks“, 4. Auflage, DFTA und Prof. K.-H. Meyer One of the major application areas for aqueous printing inks is the corrugated board printing. Here the inks are for the pre - as well as for the post-print – a generally suitable water based ink systems for all absorbent substrates such as paper and tissue. In the paper area, there are a variety of end applications such as paper bags and newspapers, but also applications regulatory differently considered need to be, such as bakers bags and muffin cups. When printing by tissue we distinguish different application areas such as E.g. napkins, kitchen towels, table cloths, but also toilet papers. All applications must meet different criteria of resistances so that there are a variety of ink systems in the market. Printing on film are becoming more and more important. Some years ago the printing of PE was just possible, but nowadays there are printed a lot of flexible packaging as mono films as well as laminates.

Product Range Rotogravure Decor printing Giftwrapper Wallpaper furniture foils floor-covering/laminate Substrate Impression cylinder Printing ink Gravure cylinder paper/non-woven vinyl Bildquelle: „Technik des Flexodrucks“, 4. Auflage, DFTA und Prof. K.-H. Meyer We have a large portfolio that can be used in gravure printing. The largest amounts are required today in the field of furniture foils. Also wrapping paper and wallpaper are mainly in gravure printing. Waterbased systems can be used very well for the printing of aluminium foil. Since there are even subgroups in each of the applications listed here you can perhaps imagine how many exist different types of waterbased inks on the market.

Primer & Coatings Primer Effect Coatings Functional Coatings matt & gloss laquers Functional Coatings antislip coatings barrier coatings Do not ignore the area should remain primers and coatings. Some substrates to be coated with waterbased primer before printing. A large portfolio for Coatings is available on the market. I will mention here only briefly on the most common such as glossy and matt lacquers with those effects are to be achieved. There are still the function coatings like E.g. antislip coatings.

Overview History of water-based printing inks Composition of water-based printing inks Application methods and product ranges Advantages of water-based printing inks Summary and conclusion

Broad Technical scope Absorbent substrates Non Absorbent substrates Good print hold out, cost effectiveness, excellent printability characterize water- based inks. Traditional limitations are being overcome e.g. high speed printing, chemical resistances. Can be used advantageously in combination with other ink technologies and print techniques in a wide range of applications. Market requirements for technical performance can be achieved, eg printing speed, print resistance, bond strength. Water-based inks gain ground as a complementing technology in this application field. Technology is characterised by High colour strength coloured bases. Consequently low ink film weights can be applied with associated advantages.

Socially and Environmentally responsible Environmental profile Workplace safety VOC emissions are very low. Waste water produced can be readily cleaned limiting the impact of water consumption. Work to develop monomers produced from bio-reactors is well advanced, leading to a possibility to decrease dependence of fossil fuel based feedstocks in the future. Water-based inks are non flammable and do not require special workplace precautions relating to flammability. Solvent contents are reduced to a minimum - need for surveillance of workers health with respect to solvent exposure is low.

Competitive „Total Cost“ Profile Emissions monitoring costs Insurance costs Diluent cost Waste Disposal Costs Ink Cost Invest-ment costs

Overview History of water-based printing inks Composition of water-based printing inks Application methods and product ranges Advantages of water-based printing inks Summary and conclusion

Summary and conclusion Water-based inks gain in importance: Modern ink formulations and adjusted printing/technical parameters open up a broad variety of applications. Water-based inks are in accordance with EuPIA Exclusion Policy and can fulfill regulatory requirements for food packaging if neccessary. Main applications are flexo and gravure printing with a large product range including laminated food packaging. Water-based inks offer a positive environmental profile. Due to their composition handling of waterbased inks is non-critical. Total cost profile is competitive.

Summary and conclusion Water-based inks are already being used widely due to their strengths today. In the future they will take their rightful place in each application. Image source: ACTEGA Colorchemie