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What is 7-305 T UV screen printing mesh?

I'll bet the printed selvadge edge of your mesh says "Pecap LE 7" before 305. LE for Low Elongation.

You have 305 threads per inch, each with a nominal thread diameter of 34 μm.

You have old mesh based on the "Old nomenclature" T which was phased out of Swiss mesh branding before 2000. Modern mesh from Sefar has been improved over the last 15 years.

UV means it is calendared on one side (the shiny side).

UV ink requires a very thin deposit so UV energy can penetrate all the way through the deposit to the substrate for a complete cure so factories flatten one side to make the mesh thnner.

There is no reason you couldn't print plastisol ink through this mesh - but your deposit will be quickly absorbed by the fabric you're printing on.

Yes, it's on hand - but only you will know if it will work for you.

Homework
S E F A R - Screen printing mesh - SEFAR PET 1500


=======================================================
Cut & pasted from the Sefar Screen Printing Handbook (c)1999 :

Mesh count and thread diameter
The terms ”mesh type” or ”mesh specification” are similar
descriptions of the mesh count per inch, together with the thread
diameter.

Example: 305-34 indicates 305 threads per inch, each with a
nominal thread diameter of 34 μm.

The nominal thread diameter refers to the diameter of the unwoven
thread.

”Mesh type” is a relatively new term that replaces the widespread SL/S/M/T/HD nomenclature.

New nomenclature Old nomenclature
305-31 305 S
305-34 305 T
305-40 305 HD
380-27 380 SL

Mesh type description
W = White
Y = Yellow
CY = spun dyed, yellow
PW = Plain Weave
TW = Twill Weave
UV = One Side Calendered



1.6 Calendered screen printing mesh Pecap UV
Screen printing inks contain solvents that evaporate during the
drying process, thus reducing the thickness of the ink volume.
UV-cured ink, by contrast, contains very little or no solvents. This
means that curing does not significantly reduce the thickness of the
ink volume.

The high ink film left by UV-cured inks often produces problems:
- UV light does not adequately penetrate a thick ink layer, especially
when it is heavily loaded with pigment. The ink is incompletely
cured as a result.

- Multicolor halftone printing:
If the first two colors are too thickly layered, there is barely space
for the third and fourth colors between or on top of the points
left by the first two. This results in color shifts, smeared print, and
moiré effects.

Recent years have seen major progress in weaving technology. This
makes it feasible to produce even the finest meshs in a 1:1 weave.
The resulting trend is towards increased use of finer, uncalendered
meshs that offers increased printing resolution and better ink control
characteristics. For this reason, the range of calendered mesh types
have been reduced.

The current range still includes the following mesh numbers,
available with a maximum width of 81 inches:

Pecap LE 7 - 355-34Y PW UV
Pecap LE 7 - 380-31Y PW UV
Pecap LE 7 - 380-34Y PW UV
Pecap LE 7 - 420-31Y PW UV
Pecap LE 7 - 420-34Y TW UV
Pecap LE 7 - 460-31Y TW UV

These mesh types are suitable for printing with UV inks and lacquers.
Pecap LE UV is calendered on one side of the mesh.

The calendered side is shiny, the other side is dull.
 
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Good info- Yet another book I need to find. :)

I'm wondering about the end of the quote though--I was always under the impression that the calendared side is the flatter, shinier side.

And you want to make the flatter side the print side of the screen when you stretch, not the squeegee side--if I'm not mistaken.
 

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Calendared side of mesh

I'm wondering about the end of the quote though--I was always under the impression that the calendared side is the flatter, shinier side.

And you want to make the flatter side the print side of the screen when you stretch, not the squeegee side--if I'm not mistaken.
I apologize. In summing up important details, I didn't type correctly.

The last line of the text I pasted in my other post:
From the 1999 version of the Sefar Handbook for Screen Printers

The calendered side is shiny, the other side is dull.

Sorry.


To answer your question about which side to stencil, I again paste from the 1999 version of the Sefar Handbook for Screen Printers

There are two techniques for reducing the ink deposit:

1. By stretching the mesh with the shiny surface facing the
squeegee, UV mesh reduces the ink deposit by around
10 – 15% compared to uncalendered mesh.

2. If the shiny surface is stretched facing the substrate, the ink
deposit is reduced by around 15 – 25%.

The degree of ink volume reduction depends on a variety of
additional factors in the printing process, particularly the ink’s
rheological characteristics, which vary depending on the color. It is
therefore impossible to give exact figures.

Regular mesh 100%

Calendered side = squeegee side (RK) approx. 10–15% reduction
Calendered side = substrate side (DK) approx. 15–25% reduction
 
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