A guide to wallpaper printing The available design styles and finished printed looks of wallpaper are so numerous that it would be almost impossible to fully detail all of the printing permutations available. This is easy enough to accept once it is understood that wallpapers can be printed with water or solvent based inks. They could be part printed on one print process and then transferred to any one, or more, of the other available processes. The paper grade also affects colour and so plays its own part. For purposes of explanation and understanding, the It is important to note that no print process is individual print processes have been explained in superior to any other, they are just different. The detail on the following pages. Each of the processes desired finished effect being individually tailored to are, or have been, the most commonly used for the suit a particular client or marketplace. mass production of wallpaper within the industry It does naturally follow that as technology has over the last 500 years. They have been sequenced advanced over the years the more recent processes in date related order as they were introduced for will produce more technologically advanced wallpaper printing. wallpaper. However, this isn’t always the desired 1 BLOCK PRINTING option as, in particular, processes such as Block and 2 FLOCK (BLOCK PRINTED) Screen printing are desired because of their 3 PAN (TROUGH) PRINTING idiosyncratic character. Perfect butt joins from Block 4 SURFACE PRINT printing are no more achievable today than they 5 FLAT-BED SCREEN (LONG TABLE) were 450 years ago and the flaws and blemishes 6 ROTARY SCREEN produced by the crude method are very much a part 7 FLEXOGRAPHIC of the charm. 8 GRAVURE 40 A GUIDE TO WALLPAPER PRINTING 123 456 Now, regardless of which print process is utilised, the design FALL-ON DESIGN itself is built-up in one of two ways, or possibly a combination of 1 All over background ‘pad’ colour 2 All over texture both. In simple terms it will either be 3 Note how gaps have been left in the trellis to avoid it showing through the top prints In-register, Fall on or a combination of both. 4-6 Three top prints laid on top of each other THE FALL-ON DESIGN The fall-on route continually prints each colour either fully or partly on top of the previous colour, building up the complete design as it does so. Unlike ‘in-register’, more care and skillful consideration has to be given to the choice and subsequent use of colours, as any colour falling on top of another will almost certainly change both of them. This is due to most printing inks, particularly solvent based ones, being semi-translucent. 41 A GUIDE TO WALLPAPER PRINTING 12 34 THE IN-REGISTER DESIGN An in-register design is where each colour is all the other colours to print onto clean white paper. ‘registered’ to sit tight against the previously laid (This cylinder is called the choke cylinder). down colour without any overlapping. This would Printing onto a white background means that the apply to all the subsequent colours laid as the design subsequent colour is not influenced by the previous is progressively built up. underlying colour. eg: if you print the colour red onto The beauty of this route is that it allows the white - it remains red, whereas if you print red onto achievement of very strong, bright colours. This is yellow, it will appear orange. because a hole is left in the first print colour to allow 42 A GUIDE TO WALLPAPER PRINTING 56 78 Note no overall background colour. Each subsequent colour is ‘fitted’ inside the previous one, the first colour being referred to as the ‘choke’. 43 A GUIDE TO WALLPAPER PRINTING 1 Block printing Magnified view of Block printed wallpaper, The first known method of wallpaper printing. demonstrating how the thick stodgy inks are ‘splodged’ as the printing block is lifted off. Recorded as having been used as early as 1509. Prior to this plain paper was pasted to the wall and then hand drawn and coloured in by artists. Continued as the only ‘real’ means of printing wallpapers until the introduction of the ‘Printing machine’ some 300 years later. WHILE TECHNOLOGY MAY HAVE whilst having excellent wear REVOLUTIONISED THE PRINT qualities, were simply too hard for INDUSTRY LIKE NO OTHER, IT cutting by hand. HAS FAILED TO PRODUCE ANY However, in recent years there METHOD THAT MATCHES THE have been limited developments TACTILITY OF HAND BLOCK whereby other more modern PRINTING . ITS SIMPLISTIC materials, such as Linoleum, plastic BEAUTY COULD NOT BE and metal, have become available. DEMONSTRATED ANY BETTER THAN IN THE MANUFACTURE OF Given that these materials are THESE TRADITIONALLY PRINTED inherently more stable than wood WALLPAPERS. that can twist, warp and crack, it would be a fair bet that had they Historically, the wood of fruit trees, been available 400 years ago, they such as cherry and pear, has been would certainly have been used. used for the printing blocks as this timber offered the right balance The look of block printed between durability of use and the wallpapers, peculiar to itself, is not practicalities of cutting the block. necessarily created by the Softwoods, such as pine, could not materials used to make the block, withstand the pressures put upon but from the ‘splodge’ created by them by the press; whereas harder the vacuum as the printing block is woods, such as oak or maple, pulled away from the paper. 44 A GUIDE TO WALLPAPER PRINTING 1 2 34 For the process of printing, the in placing the block exactly into 1 Wooden blocks each with a unique reference craftsman utilises a table, padded position. Accuracy and strength of number on showing the design and the pitch number with blankets, on which the paper colour is effectively governed by is laid. Next to the table is a the printer’s ‘gut feeling’ on how 2 Printing in progress - the block being wooden, wall-sided tray, inside of much pressure needs to be manoeuvred into place using the crane which there is an absorbent applied to the back of the block. 3 Ink preparation - the wall-sided tray with the blanket that is saturated with the absorbent blanket saturated in pigment After each individual colour has coloured pigment. been laid the paper is ‘festoon’ 4 An example of an inked wooden block The printer colours the block by hung for 4-5 hours to let the thick lowering it down onto the colour water-based inks dry, before the tray, and once sufficiently inked is next colour is applied. Once all of lifted and manoeuvred over to the the colours have been printed the paper by an arch lever system wallpaper is PVA lacquered for (crane) before being pressed down protection, before being manually to create the print. Pins on the trimmed and individually hand side of the blocks guide the printer wound. 45 A GUIDE TO WALLPAPER PRINTING 2 Flocking (block printed) Close-up shot of ‘rayon’ flock on block printed Believed to have been introduced in the late 17th background. Fibres stand on end in the block printed glue as a result of static electricity. Century, possibly inspired by the flocked canvas hangings popular in Holland. The grandest designs of this period would have had a 6 or 7 ft pattern repeat, made up of 3 or 4 blocks. Originally the flock would have been a by-product of the wool industry, however, this was later replaced by rayon fibres. Rayon fibres, when subjected to static electricity, stand erect giving a plush velvet type feel. Rayon also, compared to wool, made the wallpaper spongeable – this was to prove an important step forward. FLOCK WALLPAPERS ARE substitute it for an adhesive. This TRADITIONALLY PRODUCED adhesive is very tacky and is USING THE BLOCK PRINTING comparable in looks to white gloss METHOD. (SEE PAGE 44). THE paint. It can be tinted using SUBTLE DIFFERENCE BEING THAT pigments to mimic the colour of ONE (OCCASIONALLY TWO) OF the flock being used, this adding to THE COLOURS ARE SUBSTITUTED the dramatic effect of the finished FOR RAYON OR WOOL FIBRES paper. THAT GIVE THE PRINT A SOFT Once the paper has been printed VELVET-LIKE FEEL TO THE TOUCH. with glue, the length of wallpaper To achieve this the printer is drawn across a canvas bed progresses in the normal block where the fibres are traditionally print way, except that instead of scattered, normally by hand, from using a colour pigment he will above. Wooden canes or battens 46 A GUIDE TO WALLPAPER PRINTING 1 2 3 constantly beat the underside of normally by around 25-35%. There 1 An example of a double-flocked wallpaper the canvas bed, making the rayon are two reasons for this, firstly 2 Block printing of the glue for the second fibres rub together as they jump up because flock is very heavy and a colour of flock on a double-flocked paper and down. It is this rubbing that is standard paper would not hold the the key to good flock printing. As weight. And secondly, the paper 3 Flock being hand-scattered from above whilst the canvas bed, that the paper is the paper is beaten static has to withstand a lot of abuse lying on, is beaten from underneath electricity is created; which has the during the beating stage and a desired effect of making the rayon thinner, lighter paper would tear fibres stand on end, like iron filings easily.