By Mick Orr, Applications Training Specialist for Chromaline
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When it comes to screen printing, there are four types of emulsion systems to choose from: direct emulsions, capillary films, indirect stencils and direct/indirect systems. Which one is right for you? It is time to kick the tires and find out.
A couple of weeks ago my wife and I decided it was time to trade in the old jalopy for a newer one. Her car was just too small to handle all the kids that she has to transport around town. We have two children who sometimes sound like an entire hockey team in a small car. Man, how I hate looking at cars! Every one of them costs a fortune and every one is different. Plus, each of them have their good and bad points.
Choosing an emulsion system is like choosing a car. Everybody is looking for something different. You’ve got to kick a few tires to find the system that is right for you.
I made the mistake of telling a friend that I was looking for a vehicle and next thing I knew, everyone was giving me advice. “Buy this one. Buy that. Don’t go there. Go there.”
With all the information we compiled after visiting what seemed like every car dealer in the northern hemisphere we finally got the car that suited us. I hope.
Choosing An Emulsion System for Screen Printing
Buying an emulsion system can be similar to buying a car. There are hundreds of films and emulsions to choose from. Your job is to determine what will work best for you. Consider the following seven questions before choosing the system that is best for your. In other words, you’ve got to kick a few tires.
1. Should I use capillary film or direct emulsion?
Choosing to use capillary films or emulsions is similar to choosing the type of vehicle you drive. Should I buy a van or a car? It’s really a matter of choice. They both work very well. Same goes for capillary films and emulsions. Films generally print sharper and are easier to use, while emulsions may be harder to use but are typically tougher against wear and tear.
2. What type of print resolution is needed?
Asking yourself what type of resolution you need is like asking, “Do I need a sports car or a van?” (Personally, I do need a sports car, but don’t ask my wife). There are emulsions on the market that can resolve two mil lines, but do you really need to resolve that fine a line? Textile printers should be more concerned about ink deposit than trying to print 2 mil lines. Examine what you are trying to print and what you are trying to print on.
Plastisol printers take a serious look at our Chroma/Tech® PL or Chroma/Tech® PL-2. They are the “sports car” of direct emulsions. Both shoot fast with quick build up and with all the resolution needed to do textile prints.
3. How important is stencil durability?
When it comes to stencil durability, what’s important is that the stencil makes it through the print run. So for short runs, is it really necessary to have a bullet proof stencil? Take the type of job into consideration when determining your stencil durability needs.
4. Is my equipment adequate to handle the stencil specifications?
Your equipment can be a factor in determining the best stencil system to use. Maybe you should look at getting better equipment that will help you become more efficient and give you higher quality, i.e. metal halide exposure units, high pressure washers, microscopes, etc.
5. Will this new stencil system be better than what I’m currently using?
Is this stencil system any better than what you are presently using? I had to ask myself the same thing when looking at a new car. Possibly, the system you are using just needs a little updating. By rechecking exposure times, thicknesses, drying time, coverage and the amount of downtime caused by having to reshoot new screens, you may find that it’s not the emulsion that needs to be replaced but the way it is processed.
6. How easy is it to use?
No emulsion is idiot proof, but capillary films come close. They’re already presensitized, supplied in a specific thickness and are easy to learn. If ease of use is important to you, then a capillary film system may be the one for you.
7. How expensive is it?
This is an easy question to answer when buying a car. They all cost too much. It isn’t as easy to answer when looking at emulsion systems. There are additional questions to consider such as: Will this emulsion system give me the print quality that I demand every time? Will this emulsion system be easy to use?
Upon examining your labor rate, an expensive capillary film might end up costing less than an inexpensive direct emulsion when you add up all the factors involved in making a quality stencil.
Let Us Help You Choose An Emulsion System
If you need help locating an emulsion system for screen printing, the team at Chromaline can help. We sell all four types of stencil systems, including direct emulsions, capillary films, indirect stencils and direct/indirect systems. If you need help buying a sports car talk to my wife, I’m sure you will enjoy your new van. But if you need help buying an emulsion system, talk to me.
Mick Orr, Chromaline's Technical Guru and Applications Training Specialist has been in the screen printing industry since 1970 with printing experience in a wide range of applications from membrane switches, to textiles, specialty graphics to faceplates and more. If you have any additional questions about drying screens or the screen printing process, please contact us today.