Problem - printing colors on a transparent sheet

[Bad Disciple]

Hello everyone,

I've got two problems, a pain-in-the-ass for the moment.
I need to do some presentation work using transparent sheets as layers.
(Not with projectors, just supperposing transparent sheets.)

1.
There's a color problem when printing on the transparent sheet. I must print
colored shapes on a transparent sheet which, after printing, will be put on
the top of a background and must hide other shapes underneath. In CorelDraw I've
made them uniform colors and they hide the background layers. But when
printed on the transparent sheet, these colors become transparent and you
see the background. Could someone throw light about how could I make the top
colors print non-transparent?

2.
Also, I have a "white color" issue. I want to print white characters or
shapes and want them printed on a transparent sheet so that they appear
white when put over a dark background. In CorelDraw it works just fine, but
when printed on a transparent sheet, the white objects are just NOT printed,
so they don't appear. How can I make white appear white when printing on a
transparent sheet?

Thanks in advance.

BD

[steve.ledger]

Welcome to the Forums.

How can I make white appear white when printing on a
transparent sheet?

I assume you have a printer with a white ink cartridge?

[meltsner]

Everything works great on screen only doesn't it Welcome to the slightly disappointing world of printers...

1. Very few printers will actually print totally opaque, especially on transparent sheets. Especially if it's an inkjet, but even lasers won't do it completely either.

2. You will have to have at least a six or eight color [inkjet] printer to print white, and believe me, it is NOT worth it!!! White ink is known to cause some problems and is very hard to keep flowing smooth. So in short, no, you can't print white. Unless, of course, you have a huge thermal printer with spot color capability. And that's correct, anything "white" on-screen will print NOTHING in it's place. (CMYK value of 0-0-0-50 would of course mean you have a 50% [50 black, 50 white, or in other words, nothing] black fill, so half of that object will be transparent when printed!!)

[coza]

Bad Disciple,

One process that comes to mind, would be to have the transparent sheets silk screened. To get the Artwork right for the colour separations - I would use a spot colour palette, there you can choose a 100% Pantone white.

George

[handrawn]

Hi

well I realise this may not be the solution you are looking for but, in the absence of the right kind of printer, you might consider the old fashioned way:

either:

a - print to paper, cut out, stick onto the transparent sheet [ you could print outlines onto the sheets to determine position]

b - if it it acceptable for the shape outlines to be visible - hand color the transparency with opaque color, on the reverse, so that the printed black outline on the front masks the inevitable rough edges of the color

[hectorvector]

Inks even spot color inks are inherently transparent. However, silk screening uses opaque inks so that they are not as much effected by the colors of the t-shirt. With that you can use a white spotcolor as your base. The silk screen process can print on most items, probably on acetate too.

The other option would be to get some white vinyl and cut it to the vector shapes you need and transfer those to your acetate. This could be used as a substitute for ink for whatever you are doing.

[Bad Disciple]

Ooooops! Sorry, I don't know how did this huge font happen to come.
Here copied normally.

Hello back and thank you all for the feedback!

I understand now that no inkjet and no laser printer is able to print opaque colors.
It sounds interesting what you say about this silk screen, but I don't
understand what it is exactly, is it a (T-shirt) silk sheet on which you print
with an inkjet printer or what? I need a great precision with my printing
because it's a sheet which will be put on the top of other sheets with precise
matching on fine details.

I was also told about another method called something like "serie-graphic" or so.
This is to be done with a printing office.

Anyway, it's quite a complex issue and I MUST find a solution.

Thanks again for your feedback.

[handrawn]

ask a Printer

[meltsner]

I could attempt to explain but I'll let Wikipedia do it better. http://en.wikipedia.org/wiki/Screen-printing
In short, it's 'pushing' ink through a silk screen (thus the term), which has a negative of the image applied which allows ink to pass through only the "non-solid" areas (objects). Just my simplified version!!
Screenprinting can be expensive on low quantity orders (if even available) as most screenprinters charge a setup fee, and most have a minimum quantity order. Another possible (?) option would have a print shop cut you a decal (vinyl) to stick on the sheet. Should be much cheaper, but won't have quite the definition of a printer.

Don't know about the 'serie-graphic'??