Going be informal here and more like others who are doing a hobby or something technical on forums from the internet so excuse me.

I've been learning a lot about this and I've found the lower class modern color laser printers even from high quality brands are anal about smoothness and composition compared to higher class ones which can handle more roughness. Lower classes are also somewhat touchy with opacity and certainly gsm. Failure to meet the quality recommendations which are hard to find on the official documentation(s) for any leads to mixed colors fusing wrong even if it's not considered damaging invalid media. I'm sure the inside of my printer is becoming a mess from the acceptable but non-optimal paper as the tires and scanner has already and looks like they need to be cleaned at a low page count. Even if it's still working in that state.

Maybe what I'm stating is obvious and I'm being punished for not having unspoken common sense with color laser printers. I have used color laser printer compatible paper this whole time but of course colors didn't mix correctly from the crevices in "smooth but not smooth enough" paper. Duplex printing makes not meeting the correct criteria worst. It's as if once the paper gets back in the ability for handling the crevices is worst by like 30% and it will only do it correctly with the right smoothness and gsm.

Now for my question on my weird learning project now that I've given background.

Where do I find black paper like this.
* 75-90.5gsm
** Can be a bit more room here. Printer can handle 60-105gsm but this is unoptimal for other functions and quality.
* sheffield units of 50 or at least in ∓10 error of that, probably ∓5 is about as far as it will go?
** This is generally called super smooth or ultra smooth. Basic smooth is not good enough and colors fail to mix in the crevices.
* opacity 90 or higher
* non-synthetic and no cotton at all
* un-coated
* Won't cost 100+ USD for a ream.

I have another question, I'd like to somehow print on the folding side of a laser printer envelope but I don't know how you would keep it flat and in place while going in for that pass? I'm going list what the envelope needs to be like from these recommendations too. Sorry to whoever is handling this forum if this should be a new thread. I'll do corrections if needed. I've kept my exact printer out as I think these questions can help others in a more general sense.

How do I find black laser printer envelopes like this?
* 60-105gsm, heavier is probably better up to 90gsm
* Prefer #10 but it can optimally take #9, #7(3/4), DL, C5 and B5.
* I'm sure the sheffield has to be 50 even more than normal paper if I want any mixed colors but I worry about it getting stuck at 50 without a higher gsm.
* opacity 90 or higher
* non-synthetic and no cotton at all
* un-coated
* No windows or other weird appendages that shouldn't go in a laser printer but if there must be windows they must be made for laser printers frying them and now I have to avoid printing on the windows, so no windows. Maybe later with the windows.
* Gold border would be nice on a black envelope. I'm sure it might be possible to print one in but I'm probably going to be paying a lot for these so less toner usage would be nice.
* Won't cost 250+ USD for 100 of them.

A Extra is different colors of these requests like green and brown paper or envelopes.

Thank you for the detailed explanation. What you’re describing with toner fusion, surface smoothness, and duplex sensitivity is consistent with how many desktop color laser printers behave, especially lower and mid-range models.

Unfortunately, we do not currently offer a black paper that meets both your GSM range and the extremely low Sheffield smoothness values you’re targeting.

The closest option in our range would likely be Lessebo Colours Black 120gsm. It is an uncoated, non-cotton black paper with a relatively smooth surface and good overall converting quality. However, at 120gsm it exceeds the maximum paper weight specifications you listed for your printer.

For your project, you will likely have the best results searching specifically for papers marketed as “digital toner certified” or “dry toner approved,” rather than general “laser compatible” stocks.

It's a enterprise one almost made to be put on the ground but mid-low class on the model list. Pretty heavy for a desk but could work barely on a desk and it be scary during a earthquake or a angry worker having a outburst on a desk. At its form factor it's small but tall with extra trays. Would have to keep standing up to get those printed papers if I put it on my office desk as it has paper come out tower like near the top. Don't really think that changes much from common sense here due to experience proving it's still true. Thought 2020+ designs in this grade would be a little more forgiving in general but you know the rest and it wasn't made obvious before purchase.

I should've spent the extra 200USD on the mid class deal now but the return window has passed and this project isn't why I setup the printer. The mid class deal was missing some hardware too that the client wanted. Client is happy at the quality and price for a consumable hack they have someone else handling. Maybe LP can accept the custom paper requests that's a invalid page on the site currently in the future? Do you handle shipping in a way which doesn't ruin paper like most online stores do? Might be by that point enterprise low-mid class color laser printers will handle rougher surfaces better.

Do you have any ideas about getting the flaps side of a laser printer envelope color printed? I can see how if a laser printer doesn't support duplex with a envelope and from what I understand about color fusing now that this is probably impossible. If anyone has an idea to make the flap side of an laser printer envelope act flat as the top side the whole process, please tell. Of course the laser printer isn't immune to chemicals melting inside it and getting all over so common envelope adhesive is a strong no.

Lower middle class as in barely middle class, not mid-low. Bad typo. I'm calling it classes as the printer's models isn't exactly linear in range. There's different capabilities too as it's multi-function or not for example and the different functions can differ in range and it's sold in category model lines. By the category model line logic if you remove the multi-function, it's lower middle. Client needed multi-function and some weird legacy thing only enterprise printers still had around 2020 and now that's going away too.

I'm going look up your suggestions now. Good day.

I'm not knowledgeable about this either but you made me have an idea.

The working optimal paper I'm currently using is 98 whiteness. Is there a heat resistant dye or such I can use that would keep the paper from changing it's composition after the process or post-process is complete if done right that could be easily applied to a ream in total? Somehow not affecting how the toner is fused to it? Remember just like the manufacture stated the paper is no-cotton and has no coating.

Don't think it will work for #10 laser printer envelopes. They still have adhesive that is protected during printing and that protection is going get destroyed by this process and make a mess. I'm open to ideas here.

Thanks for the additional detail.

Legion focuses on paper rather than print equipment, so we try not to overstate expertise on the printer side. We can produce custom papers, but custom manufacturing typically involves large minimum orders. In most cases, the best path is finding an existing paper already optimized for dry toner or digital printing applications.

As for shipping, both Legion and our distribution partners put significant effort into protecting paper during transit, especially sheeted products.

On envelopes, most commercial envelope printing is either done on laser-compatible pre-converted envelopes or printed before the envelope is folded and glued. We are not envelope-printing specialists, but from what you are describing, printing heavily on the flap side of a folded envelope may be difficult on many office laser printers due to folds, thickness changes, and adhesive limitations. Laser-compatible envelope adhesives are specifically formulated to tolerate fuser heat, while standard adhesives may not be suitable.

That is probably beyond what we can responsibly advise on from the paper side.

Once a paper is dyed, chemically treated, or otherwise modified after manufacturing, it becomes difficult to predict how it will behave in a laser printer, especially regarding toner adhesion, heat stability, feeding, and potential residue inside the machine.

In most cases, the better route is finding a stock already manufactured for dry toner or digital printing applications rather than altering an existing sheet after production.

On the envelope side, your concern about adhesives is understandable. Laser-compatible envelopes use adhesives formulated to tolerate fuser temperatures, but additional processing or heating steps can change how those materials behave during printing.

Not finding options unless custom right now but thanks for helping. Now I have more proof pointing towards the printer isn't defective and I don't need to warranty it or fix it myself before installing it for the client. Was having a bad multiple week issue with that. Client doesn't need black paper but I can use the printer freely within reason for a few years once it's installed and I'm planning to get a laser color printer myself if I can find enough use.

As LP seems trustable given the right configuration for the paper. Is 5000-10000 around the minimum? How much is the up-cost compared to run of the mill 5000-10000 you can find anywhere vs custom?

For the safety concerns, later I might get a deal for a color laser printer that I'm willing to take apart and service myself without warranty. So you can relax the advice responsibility for that case. It is a weird project of mine for learning but maybe you can point me at a open forum for envelope-printing specialists or the printer side? Same for mixing something in the paper to change the color without issue? I haven't found many proper communities and finding legion's forum was already not straight forward.

Do you know of any enveloping machines that will reliably fold and apply laser printer ok adhesive with a laser printer wrapper over the adhesive to be pulled off and then applied? Such that the envelopes that come out will still be flat enough to print on the flat side of the envelope and be loaded into trays as if it was a laser printer envelope of a standard form factor like #10? I tried looking but have no idea what these are called nor where I should look in non-enterprise terms for something that doesn't cost thousands.

I'm corrected. It can take card stock up to 200gsm but no duplex. I am completely ignorant on handling card stock or how I'd make it take Lessebo Colours Black 120gsm, as card stock.

Thanks for your questions. There are a lot of variables involved here, and we'd be happy to help you sort through them. Please reach out to us at info@legionpaper.com, and we'll connect you with one of our paper specialists to discuss your project and recommend the best options.

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