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screen printing => Equipment => Topic started by: Steve Harpold on March 07, 2015, 08:28:46 PM
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Hey All,
While I was discussing the Fire Fly system i saw a lot of comments regarding LED exposure systems. Below is the stats on the Brown LED system released nearly 3 months ago.
Standard Led unit:
Size: 1 - 23x31
Photopolymer: 15-25 seconds
Dual cure - 1:30 - 2:00 mins
Also available 2- 23x31
LED X Series
Size: 1 - 23x31 or 2- 23x31 or size 48" - 48" and 48" x 72"
Photopolymer- 3-12 seconds
Dual cure - 30 - 1:10
The Brown led exposure were designed using a light modeling software to eliminate/reduce undercutting. The led light sources are 4" away from the glass (will solve the issues of heat on the glass the others have experienced) The system is built on a 4" x 4" grid allowing for it to deliver a even light across any size frame.
This system will also be at ISS Atlantic city show
Again thanks and I look forward to demonstrating The Fire Fly, Dragon Air and Led exposure system at the Show.
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You got any pics you can post for those of us not hitting the east coast next week?
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Pictures and details can be found here: http://brownmfg.net/p/372/led-exposure-system (http://brownmfg.net/p/372/led-exposure-system)
The LED system also has:
10 programmable pre-sets
Delay vacuum draw down
And Amber safety lines on a separate channel.
Brown mfg is achieving some of the fatest exposure times in the industry with only 42 leds total, to expose a 23x31 screen.
What this does:
Reduces the number of failure points by nearly half competitors
Speed: fatest times reported
Heat: removes the issue of heat at the glass
Undercutting: similar to old style black light or flourescent bulbs putting them directly next to the surface and not specifying the angle of light ( buying bulbs of the shelf and placing them in a exposure box) will result in the same performance issues commonly referred to before.
We have procurred custom proprietary LED's which are ordered at a specific angle and wave length. It allows us to put the LED's 4" from the surface and maintain the angle of light desired, eliminating undercutting issues. The custom power and wave length maintains speeds from that distance away.
Thanks for the interest
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Can you comment on the wavelength of the leds? Are they multi-spectral?
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I guess the best answer is no I cannot elaborate on that as these items are proprietary to Brown Mfg
I can only prove thought testing and trials.
Thanks for the interest
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Stop by the Atlantic city show and I can better answer all questions.
I also sent a machine to SPSI for their open house March 17-19
The race is on, I can confidently quote all emulsion types under 1:00 minute!!
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What's list price?
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Lowest cost unit handles one 20x24 screen
Image area: 16x24
Photopolymers- 25 seconds
Dual cure - 1:30 - 2:15
2,495
Low power unit
Image area: 23x31
photopolymers - 25 seconds
Dual cure - 1:30 - 2:15
4,295
High power
Image area: 23x31
Photopolymer - 5-12 seconds
Dual cure 35 -1:15
5,995
Recommended unit
Image area: 23x31
Photopolymers: 2-12 seconds
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Here go again. Eliminates the under cutting. Please post some data to support the claims. They are using blue LEDs. The spectrum will be in the higher end of the spectrum. They are also cheaper then the violet LEDs not that matters as long as they work. My guess is they are using 15 degree beams at 4" but maybe 30 degrees. Didn't want to do the calculation. If they are 3w at 42 it would be 126watts and 5 watts 210 watt total.
I have a DIY unit that I am willing to put against any of these commercial units. I know though everyone isn't willing to do a DIY. Right now it's only 100w soon to be 200w. Maybe I should talk to one of these manufactures. I haven't seen I manufacture with my design. I've tried the way the manufactures are doing LED and the results are definitely different. Although I don't have a densitometer I have compared at 500x magnifaction screen to exposed film and have done several other comparisons with other manufactures units.
Willing to expose a screen for me with either supplied screens and film or supply a exposed screen and film, I'll pay for the materials and shipping. If it's everything you say I'll support the claims.
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Here go again. Eliminates the under cutting. Please post some data to support the claims. They are using blue LEDs. The spectrum will be in the higher end of the spectrum. They are also cheaper then the violet LEDs not that matters as long as they work. My guess is they are using 15 degree beams at 4" but maybe 30 degrees. Didn't want to do the calculation. If they are 3w at 42 it would be 126watts and 5 watts 210 watt total.
I have a DIY unit that I am willing to put against any of these commercial units. I know though everyone isn't willing to do a DIY. Right now it's only 100w soon to be 200w. Maybe I should talk to one of these manufactures. I haven't seen I manufacture with my design. I've tried the way the manufactures are doing LED and the results are definitely different. Although I don't have a densitometer I have compared at 500x magnifaction screen to exposed film and have done several other comparisons with other manufactures units.
Willing to expose a screen for me with either supplied screens and film or supply a exposed screen and film, I'll pay for the materials and shipping. If it's everything you say I'll support the claims.
Would you share some pics/specs. I would to try a DIY project like this!
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Hey,
I am sure by your quick response that you like me live and breathe this stuff (Probably a little to much)
Below is a quick explanation or our exposure unit, let me know what you think, thanks
1. Angle
A. We have selected and specified a specific angle. Yes you could calculate this angle with the proper information. We used a light modeling software to come to our conclusion. We chose a distance of 4" from the glass. Consider a cone shape, place it to close and the light in the center is more intense than the outer light. Place it to far away and the outside light will tapper off our cross paths with another source. With a proper angle and distance we can prevent undercutting. (Similar to the thoughts behind a single point source *For science majors, I know single points don't truly exist but for sake of demonstration) I am not sure how competitors are handling this from .25" away from the glass?
2. Proper Wave Length
A. Ignore photo polymers as we had to tapper the power supply back to publish reasonable results. 1-5 seconds is to fast.
B. Testing 15 different diazo/dual cure emulsions selected a wave length that would respond to all
3. LED Testing
A. Though we purchase a LED built for Brown MFG, we test all LEDS Coming in the door for the selected wave length
B. Rejecting nearly 30% of all entrants
4. Power supply
A. 700 MA, we could drive the LEDS harder as they would respond and perform better. However it is important to guarantee life span than push the LEDS beyond specs.
These are the specs I am willing to share,
As Brown Mfg continues to push the limitations, there is no doubt in my mind that there are other minds pushing the same. Some days DIY guys are just flat better at it. (I am/was/and will always be on of these guys striving to push the limitations)
So....Let see whose science is better,
A. Select a trade show close to your location
B. I will provide booth space, power. You bring you DIY unit, I will bring my LEDX 2331 unit, the specs are listed above
C. I am sure we can find 3 members of this board to judge the challenge
D. Dual Cure Emulsion (Your choice) let me know ahead of time
E. Coated 1 x 1 with the round edge
F. Artwork 75lpi
10. If you win i will give you the LEDX2331 unit. (which of course will need work as your was faster)
11. If I win you purchase the the demo unit at (5,995 less 1,500 = $4,495)
I am always willing to stand behind my products even it means I have to admit someone else can do it better!
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I would agree to most of that. A few things I am not. 1 dual cure that maybe negotiable though. It's been 6 or 7 years since I've touched the stuff. Judge. What judges. It would have to be based on the actual results. That can be compared by a scoring system. Dots lost, dot size compared to the film, Why stop at 75 LPI. This was 85 LPI on a 272. Although a very simple graphic and not a great one for fine detail, I am going to redo a film and screen, line them up and take some photos from the microscope.
I am sure you products are just fine. Maybe I came off wrong but every manufacture claims this undercutting fixed while I just don't see it. You have a multi source light and it's going to be there in some fashion, I did gain some respect though cause your statements about the single point. That's all you ever hear about but yet with reflectors installed as there is in all exposure units which causes your light to bounce. Although single source light is still the sharpest no matter what type of light.
I'd be willing to take the challenge but there would be some changes to the challenge. Heck I might have to go get some dual cure to test since suppose to be better for detail work I have always just stuck with the photopolymer since since switching.
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Do you guys make a unit for 25*36 frames?
What's list on it?
What exposure times are you guys seeing with Murakami SP-1400?
How are you determining your screens are exposed/crosslinked/cooked fully? For me this is huge, if you are just printing plastisol you can underexpose tremendously and a screen will still work. Waterbase or HSA inks reek havoc on underexposed screens.
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Hey,
A photopolymer is a very fast exposure and will expose with several wave lengths. Many of which are commercially available. Dual cure emulsions are not as sensitive to such a large band of wave lengths. They preform the best when exposed to a wave length shift the NM up by 10 and they will no longer perform at all!!!! Many of the led EXPO units have a disclaimers, they will expose a photopolymer in 30 seconds or less. And for some emulsions it could be 1-5 minutes or higher. These exposure units are using commercially available sources. Simply upping the wattage without the correct wave length will not help.
Under Cutting:
The use of reflectors is counter productive to this concept. The goal is to get the cleanest light and not bounce light all over a enclosed box. However in the chase for speed many have chosen to bounce the light of reflectors as to not waste any energy. We used s light modeling software placing a led in a pattern taking into account the angle and cone that the LED produces the each beam of light covers a 4" x 4 " area. Of course there is always a small overlap, with the modeling software we are able to ensure that where that small overlap occurs the intensity of light is +/- 10%. I will post the graph on what it looks like once the light is measured.
Side note: The wattage of our system to expose a dual cure that fast is: 560 watts (in this case you have worry about proper heat sinks. Try a diazo, let me know how fast you can expose it and how clean.
Also send me a message with your info and I will send you a screen back exposed. Please mail the art with the below picture to:
Brown Manufacturing
Attn : Steve
4661 Stafford
Grand Rapids, MI
49548
Thanks
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Hey,
A photopolymer is a very fast exposure and will expose with several wave lengths. Many of which are commercially available. Dual cure emulsions are not as sensitive to such a large band of wave lengths. They preform the best when exposed to a wave length shift the NM up by 10 and they will no longer perform at all!!!! Many of the led EXPO units have a disclaimers, they will expose a photopolymer in 30 seconds or less. And for some emulsions it could be 1-5 minutes or higher. These exposure units are using commercially available sources. Simply upping the wattage without the correct wave length will not help.
Under Cutting:
The use of reflectors is counter productive to this concept. The goal is to get the cleanest light and not bounce light all over a enclosed box. However in the chase for speed many have chosen to bounce the light of reflectors as to not waste any energy. We used s light modeling software placing a led in a pattern taking into account the angle and cone that the LED produces the each beam of light covers a 4" x 4 " area. Of course there is always a small overlap, with the modeling software we are able to ensure that where that small overlap occurs the intensity of light is +/- 10%. I will post the graph on what it looks like once the light is measured.
Side note: The wattage of our system to expose a dual cure that fast is: 560 watts (in this case you have worry about proper heat sinks. Try a diazo, let me know how fast you can expose it and how clean.
Also send me a message with your info and I will send you a screen back exposed. Please mail the art with the below picture to:
Brown Manufacturing
Attn : Steve
4661 Stafford
Grand Rapids, MI
49548
Thanks
Steve,
of the two commercially available units I tested (with spectrometers), light field was at 5% and 1% fluctuation. If you are saying that you have a 10% variance in the strength of your light field on the glass, that is too much. Did I misunderstand something?
pierre
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Hey,
A photopolymer is a very fast exposure and will expose with several wave lengths. Many of which are commercially available. Dual cure emulsions are not as sensitive to such a large band of wave lengths. They preform the best when exposed to a wave length shift the NM up by 10 and they will no longer perform at all!!!! Many of the led EXPO units have a disclaimers, they will expose a photopolymer in 30 seconds or less. And for some emulsions it could be 1-5 minutes or higher. These exposure units are using commercially available sources. Simply upping the wattage without the correct wave length will not help.
Under Cutting:
The use of reflectors is counter productive to this concept. The goal is to get the cleanest light and not bounce light all over a enclosed box. However in the chase for speed many have chosen to bounce the light of reflectors as to not waste any energy. We used s light modeling software placing a led in a pattern taking into account the angle and cone that the LED produces the each beam of light covers a 4" x 4 " area. Of course there is always a small overlap, with the modeling software we are able to ensure that where that small overlap occurs the intensity of light is +/- 10%. I will post the graph on what it looks like once the light is measured.
Side note: The wattage of our system to expose a dual cure that fast is: 560 watts (in this case you have worry about proper heat sinks. Try a diazo, let me know how fast you can expose it and how clean.
Also send me a message with your info and I will send you a screen back exposed. Please mail the art with the below picture to:
Brown Manufacturing
Attn : Steve
4661 Stafford
Grand Rapids, MI
49548
Thanks
Steve,
of the two commercially available units I tested (with spectrometers), light field was at 5% and 1% fluctuation. If you are saying that you have a 10% variance in the strength of your light field on the glass, that is too much. Did I misunderstand something?
pierre
Hey Pierre, how does the 3140 compare?
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Hey,
A photopolymer is a very fast exposure and will expose with several wave lengths. Many of which are commercially available. Dual cure emulsions are not as sensitive to such a large band of wave lengths. They preform the best when exposed to a wave length shift the NM up by 10 and they will no longer perform at all!!!! Many of the led EXPO units have a disclaimers, they will expose a photopolymer in 30 seconds or less. And for some emulsions it could be 1-5 minutes or higher. These exposure units are using commercially available sources. Simply upping the wattage without the correct wave length will not help.
Under Cutting:
The use of reflectors is counter productive to this concept. The goal is to get the cleanest light and not bounce light all over a enclosed box. However in the chase for speed many have chosen to bounce the light of reflectors as to not waste any energy. We used s light modeling software placing a led in a pattern taking into account the angle and cone that the LED produces the each beam of light covers a 4" x 4 " area. Of course there is always a small overlap, with the modeling software we are able to ensure that where that small overlap occurs the intensity of light is +/- 10%. I will post the graph on what it looks like once the light is measured.
Side note: The wattage of our system to expose a dual cure that fast is: 560 watts (in this case you have worry about proper heat sinks. Try a diazo, let me know how fast you can expose it and how clean.
Also send me a message with your info and I will send you a screen back exposed. Please mail the art with the below picture to:
Brown Manufacturing
Attn : Steve
4661 Stafford
Grand Rapids, MI
49548
Thanks
Steve,
of the two commercially available units I tested (with spectrometers), light field was at 5% and 1% fluctuation. If you are saying that you have a 10% variance in the strength of your light field on the glass, that is too much. Did I misunderstand something?
pierre
Hey Pierre, how does the 3140 compare?
3140 reads is smaller than out sensor size or tolerance can measure (so 0% for all practical purposes).
Just for the record, I don't see 5% being an issue. I would have to think about 10% though. My guess is, I am not reading something right. . .
pierre
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Pierre, what would you need to measure my results, interested in doing. Willing to pay for your time if you have it.
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Pierre, what would you need to measure my results, interested in doing. Willing to pay for your time if you have it.
measure the exposure unit or the film? If you send me the films, I'll read them for you (that offer and the file are in the screen making section).
To read the exposure unit, I'd have to bring the meters to your place which would be tough. If you wanted to drive it over here, we could test it and compare it to the 3140 and the other LED readouts I have. We can measure the light intensity at 365nm and I'd have to check the other meter to see what it's calibrated to. . .
pierre
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(http://)Hey,
After, being that you have tested many units below is our testing method as well as a questions about the method you used to determine 1-5%. And for those DIY a simple inexpensive test just for fun!!
1. Method to measure lower distribution:
A. Molectron Thermopile
B. Why
These devices are very Accurate and insensitive to variations in wavelength and acceptance angle. Using this method I can confidently list s variation of intensity between 5% and 10%. I have to defend this so it easier to publish worst case.
Spectrometer method:
Disclaimer*******
(Below is the question, followed by the reason for asking. Some of the questions will obvious to a person versed in light measurement. They are not intended to challenge ideas, just listed for those following along to understand why the questions were presented)
If I have a better understanding of you method of measurement I can report back the details and how it pertains to the Brown LEDX series.
1. Where on the platen were the measurements made, directly above LEDs, or randomly placed over platen with a large number of measurements? How many locations were chosen?
If the measurement was made directly over the LEDs, the variation measured would be that of the LEDs and not representative of the entire platen area.
2. Did the spectrometer use a fiber optic? If so, what is the acceptance angle of the fiber optic? If the fiber does not have a cosine corrector, it will have a very narrow acceptance angle. Which means it will not show the total amount of light at a point on the platen but only light from a narrow angle. In other words, the light from adjacent LEDs will not be accepted into the fiber optic
3. The variation in measurement of 1% to 5% is very questionable. (Experience speaking which is always never the best idea!!!) In the field of optics and optoelectronics, a claim of 1% to 5% is very impressive when it comes to lighting. Most good measurement systems do not have the ability to measure below +/- 2%, unless you are using high quality laboratory equipment with very tight controls on methodology.
After a quick review of your method I can apply it to the Brown Led unit and report back.
The DIY project!!!
aAway to make this type of measurement (relative power distribution) on the cheap.
1. Turn an exposure unit on its side
A. Tape a large sheet of thin paper, at the corners, over a platen and turn on the U
2. Look at the paper on the platen while it is running (I don't support staying in uv light!!!)
A. The human threshold for observing variations in intensity is about 20%
B. Some of these exposure units will show defects visibly
3. Experiment continued for software nerds!!!
A. Assuming it passed the eye test than we can pretty much expect the unit to be better than 20%. The next percentage points are not so easy to earn.
B. From a distance of 10 ft away take a picture of the platen with
C. Zoom into the platen with camera and adjust distance from the platen so the resulting image is not over exposed.
D. Use image processing software to plot the relative intensity of the image over the entire field
E. Software options:
1. Matlab, Zemax, Freemat, etc
F. Attached is the Zemax illustration of the Brown LED series expo unit.
I always enjoy other thoughts and questions on how arrived at my conclusions. Let me know what you think about or testing operation as well as you experiences on your method of testing!
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Great stuff Steve... I love that you are engaging ina friendly manner with the users here! Great spirit!
I'm also glad to read about that paper method. It is one that I had thought of to test units with odd spacings between LEDs. I didn't realize we would only detect 20%... Good to know.
The camera technique is great, I'd suggest under exposing the picture a healthy bit to make sure you aren't "cheating" on accident as washed out images will read flat.
Great stuff!
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I haven't figured out how to include other peoples message in the purple box.
TCT to answer your question:
Model: LED 2962
Cap: (2) 25x36 frames
Times: 15-25 photo dual 1:45 - 2:00 (2:30 hsa/waterbase)
Cost: 7,295
Model: LEDX 2962
Cap: (2) 25x36
Times: photo: 1-15s dual 45 - 1:15 (1:30 hsa/waterbase)
Cost: 9,295
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I haven't figured out how to include other peoples message in the purple box.
Here you go
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Holy chit, actual science from a manufacturer! Brown from the backfield!
Why no diazo emulsions with LED? Under cutting too much of an issue at the exposure lengths necessary? Or just that much time isn't saved over metal halide?
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Holy chit, actual science from a manufacturer! Brown from the backfield!
Why no diazo emulsions with LED? Under cutting too much of an issue at the exposure lengths necessary? Or just that much time isn't saved over metal halide?
See post 1 and reply #7.
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Steve,
Great info!
The measurements were taken by Richard Greaves and myself over last year or so. We used three different instruments, one of which is a laboratory grade $2k+ UVA/UVB meter. Richard also has a meter by Chromaline, I think, and I have a generic 365nm UV meter by General Instruments. They all have sensing elements in the head, attached with a cable to the main unit. Readings were taken in one inch increment across the field. All the readings were taken right on top of the glass while trying to keep the sensor flat against it. Considering all the meters read similar field uniformity, I would venture to guess the readings are right. I would NOT bet my life on it, these, after all, we're not laboratory conditions, but uniformity of the results, both at my shop and ISS floor leads me to believe we did OK.
I'll stop by the booth tomorrow and we can talk some more.
Pierre
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Holy chit, actual science from a manufacturer! Brown from the backfield!
Yeah, I'm loving it... The guy can barely use the forum but isn't afraid to hop on here and let it all hang out and truly engage the people!
Not cherry picking the discussion either!
Very refreshing! I've gained a good bit of respect for Brown over the past month!
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Sonny and I were talking about Brown the other day and how much they have really stepped up their game. I am glad to see this.
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Steve,
Great info!
The measurements were taken by Richard Greaves and myself over last year or so. We used three different instruments, one of which is a laboratory grade $2k+ UVA/UVB meter. Richard also has a meter by Chromaline, I think, and I have a generic 365nm UV meter by General Instruments. They all have sensing elements in the head, attached with a cable to the main unit. Readings were taken in one inch increment across the field. All the readings were taken right on top of the glass while trying to keep the sensor flat against it. Considering all the meters read similar field uniformity, I would venture to guess the readings are right. I would NOT bet my life on it, these, after all, we're not laboratory conditions, but uniformity of the results, both at my shop and ISS floor leads me to believe we did OK.
It was pleasure to speak with you today on the LED concept. I believe I have an understanding of your proposal and it seems logical. Thanks for taking the time to illustrate the concept. I have run the simulation, if you have time tomorrow stop by, the results are intriguing!!
Thanks
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Steve,
Great info!
The measurements were taken by Richard Greaves and myself over last year or so. We used three different instruments, one of which is a laboratory grade $2k+ UVA/UVB meter. Richard also has a meter by Chromaline, I think, and I have a generic 365nm UV meter by General Instruments. They all have sensing elements in the head, attached with a cable to the main unit. Readings were taken in one inch increment across the field. All the readings were taken right on top of the glass while trying to keep the sensor flat against it. Considering all the meters read similar field uniformity, I would venture to guess the readings are right. I would NOT bet my life on it, these, after all, we're not laboratory conditions, but uniformity of the results, both at my shop and ISS floor leads me to believe we did OK.
It was pleasure to speak with you today on the LED concept. I believe I have an understanding of your proposal and it seems logical. Thanks for taking the time to illustrate the concept. I have run the simulation, if you have time tomorrow stop by, the results are intriguing!!
Thanks
Hey Steve,
Pleasure meeting you today and I mean it! It is very refreshing to see somebody with the great new ideas and willingness to explore new concepts. 'Look forward to talking more tomorrow.
Pierre
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My issue with all LED manufacturers is this:
Provide the histogram of the light. Both wavelength and watts (histogram) and proximity to surface. Don't tell me what my emulsion is sensitive to, because you have no idea, we didn't provide you that info. Many of these recipes of our sensitizers are trade secrets.
then take a 25T, and a 110T coated normally with any emulsion. Expose an emulsion calculator image with no density overlay, just used for details at your best time.
Provide the times and show that when a white rag is wiped on the inside during development and screen is wet there is no emulsion color.
When there is no emulsion color showing, are all details visible? All outlines, converging points, 12pt lettering and on the 110 halftones are showing, although they may moire a little. Try to rub the image off during development. Failure to avoid loss of details due to undercutting, or any imagery rubbing off is not a well exposed screen. Anything done post in the way of post exposure or hardeners will never equal a well exposed screen.
Then set it up a production job with the best times for each mesh on an High Solid Acrylic ink print run and print 90,000 units. While not many printers get these runs, this shows the major difference in LED vs MH. One (MH) can already print 90k runs, the other will struggle and need lots of band aid work. Again resolution of details has to be perfect, no slime or emulsion color can be rubbed off with a rag. LED's have shown issues with thicker mesh and detailed stencils in this area.
I am an emulsion manufacturer, your histogram and wattage is all I need to know. Absorbed Millijoules at proper wave lengths has to be sufficient to expose the emulsion correctly. You can't bake bread by shortening the time and heat needed. Same with emulsion, either bake it completely with proper UV light all the way through the emulsion or it will break down. Emulsion likes Multi-sprectral output, it is not single spike exposure, multi-spectral lamps aid in the exposure process to achieve optimum strength.
Image is not the same as exposure. I can expose any emulsion in ten seconds and get an image, but is it a strong image?
Plastisol can print almost any imaged screen ok. But for discharge, HSA, and high end sim process where tonal control is important there are still unanswered questions regardind any LED system.
Post exposure and hardening is just a band aid on underexposed screens, which LED often falls into, if the exposure can't go straight to screen, you aren't gaining a whole lot via post exposure on diazo and dual cures, some strength added for SBQ, but for screen strength strong light with a good calibrated reflector has not been beat yet in terms of durability.
5 seconds? What is the millijoules absorbed by the emulsion? What mesh count? What is the reading on the inside of the screen during exposure? Not the lamp side?
That number on an LED is neglible. On a 5kw metal halide, readable.
The LED's show great promise, and I have been impressed by a lot of units out there. They will only get better and for some shops work very well already. But typically my tech calls involve emulsion breakdown. 50% are DIY shop lamps, 10% fluos, 40% for those that bought LED already but can't get both details and durability in one shot. So this is all good dialogu,e would like to know more about all LED specs, but without a histogram we are working in the dark as emulsion manufacturers!
Al
Alan
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So this is all good dialogue would like to know more about all LED specs, but without a histogram we are working in the dark as emulsion manufacturers!
Don't tell me what my emulsion is sensitive to, because you have no idea, we didn't provide you that info. Many of these recipes of our sensitizers are trade secrets...
Al
Do you see a disconnect here?
You, as an emulsion manufacturer want the specific light details, but can't give the light manufacturer your specific requirements.
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The recipe is secret, but it should be no secret that diazo/dualcure likes the lower end and SBQ likes the higher end. My Nu-Arc 6K range is listed at 300-450nm, we are covered no matter which emulsion I choose. I would doubt that there are any LED units that can cover that spectrum.
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can someone tell me why the chemical recipe emulsion uv sensitivity should be a secret??
-AND-
why the UV wavelength of LED exposure units should be a secret as well?
I for one would love to have an emulsion that closely matches my exposure unit as possible, I'd think that the combination of the 2 being 'suited' for each other would make for the best screens I could possibly expose?
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My issue with all LED manufacturers is this:
Provide the histogram of the light. Both wavelength and watts (histogram) and proximity to surface.
Ditto.
I agree with Frog, there needs to be some partnership/exchange between emulsion makers and LED expo unit makers for this tech to really fulfill it's potential. We're just dipping into testing but it's obvious to me that LED needs emulsion made to respond to the LED array's output for it to truly surpass halide in any other area besides power consumption. That or the LED arrays need to be as rich in multi-spectral light as a quality halide bulb.
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can someone tell me why the chemical recipe emulsion uv sensitivity should be a secret??
-AND-
why the UV wavelength of LED exposure units should be a secret as well?
I for one would love to have an emulsion that closely matches my exposure unit as possible, I'd think that the combination of the 2 being 'suited' for each other would make for the best screens I could possibly expose?
We're both thinking and typing the same today!
The trade secrets make sense. As seen by those diy building, there is not excessive cost in the LED exposure machines if you have the right sources. Same goes for emulsion, it's practically elmer's glue with some other stuff in it. I can see why these parties protect their sources. Seems like a partnership would be about the only way to bridge the issue.
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Some reading for nerd types and/or others with time to waste...
http://www.google.com/patents/US20140038108 (http://www.google.com/patents/US20140038108)
Is Louie the guy that came out with the "Baby Joe"?
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He was posting here as Lou, so probably.
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Hey Alan,
Thanks for the quick info, all the help I can get is great.
I am not sure though how it is possible to design and build an exposure system if the manufacturer is keeping the desired wave length (be it multi spectrum) a secret. There
Are many emulsion companies for us to work with that will post desired wave length and best intensity known to date.
So from a engineering side;
1. Since we cannot perform a 90,000 shirt test on every possible emulsions, we have chosen to work with manufacturers who are more transparent about the desired exposure info.
2. If the emulsion company provides data about the relationship of speed as it relates to intensity than we can only hope that whichever exposure unit mfg company can generate the most intensity at the proper wavelength will create the best screen. (Yes more goes into but simply stated)
3. At some point just cramming intensity probably with hit the limitations of the chemistry. If these limitations are known it would be helpful for the emulsion company to provide the limitations.
A. If they are not known than, as a exposure unit manufacturer I will continue to push the boundaries.
4. If you can help with the following, it will make it easier to build an exposure system that makes the best use of your chemistry.
What wavelength do you recommend?
If using multi spectrum is better which wave lengths do you require and what is the best intensity at those wave lengths ?
If this proprietary than can you provide which elements make up the metal halide bulb you recommend? Or what metal halide bulb you recommend?
For a sales side:
1. Currently we have chosen to work with published numbers by other emulsion companies.
2. It is very hard for us to justify the tests you have listed as other companies provide the above information.
3. It is even harder if we have to first try to discover the wave length required to even begin developing or testing.
4. As we continue to push the envelope on LED technology, it is important to us to make sure our product works with as many emulsion companies as possible, and also build products that work for the masses. If we find out product does not perform as listed with a certain type of emulsion or first reaction is to use an emulsion that publishes desired results.
5. If we receive a lot requests about a specific emulsion and find our system does not perform adequately the market will push us into working with that specific emulsion.
As it relates specifically to Alan:
Does you company currently list recommended wave lengths and intensities?
Is there a good contact to work with to obtain this information?
Thanks
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Some reading for nerd types and/or others with time to waste...
[url]http://www.google.com/patents/US20140038108[/url] ([url]http://www.google.com/patents/US20140038108[/url])
Is Louie the guy that came out with the "Baby Joe"?
huh, this could be a problem for a few of the units out there. There seem to be some gaps open for the other manufacturers to get around, but some specs are pretty limiting.
pierre
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The wavelengths are not a secret, we look at the spread from 350-420nm as an optimum area of UV wavelengths. Multi-spectral across these wavelengths usually implies spikes in the 360-380 range and the 400-410 range. The issue with LED's are they intitially were single spike wavelengths. Multi spectral may consist of 2 spikes but little in between. Metal halides achieve multiple spikes with the use of precious metals. The percentage and specific precious metals used determines the wavelength(s) output of the Metal Halide lamp. With LED's this is not the case, they tend to be spike specific. Glad to share specific data on wavelengths but for an LED manufacturer the question becomes how do we achieve amplitude (wattage) in nearby wavelengths. They aid in the exposure process and resulting strength. So the question remains, how do we get multi spectral output from LED beyond 2 spikes?
PM me for specific info on wavelength sensitivity. I didn't mean to imply I won't share the wavelength info, this is pretty common in all emulsions, I just need to be careful on the sensitizers used as there are many which is proprietary info.
Al
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An article from last fall pertinent to this discussion, specifically page 5:
http://www.screenweb.com/content/an-update-uv-led-screen-exposure?page=0%2C0 (http://www.screenweb.com/content/an-update-uv-led-screen-exposure?page=0%2C0)