I had a question regarding tissue paper in invitations, and after reviewing existing threads going back many years here, it became apparent to me that no one asking or responding really knew anything about this tradition, so I figured I'd post some info for anyone like me who may be looking now, or years from now lol.
Historically, invitations were hand written... quill pen and ink pot type of hand written. As this medium did/does have a tendency to smudge if not completely dry, or if it got damp in transport to the recipient.. tissue was used to cover the print in hopes of preventing smudging. Kinda like a protective layer/raincoat.
With todays modern inks, this smudging doesn't usually happen, thus the use of tissue began its decline.
However, if printing out at home on an ink jet printer - it certainly can smudge depending on the type of paper being used. Especially if it gets damp. Professionally printed invitations may not have this happen.. but if a raised print is utilized, the tissue will help safeguard the raised print during the mailing/handling process.
Keep in mind, the tissue insert is still considered a standard to use in a formal wedding situation. File it under the category of proper wedding stationary etiquette. Or consider it under the category of the lost art of letter writing.
Is it immediately thrown away by the recipient.. the majority probably do. I know I never have as I keep the invite all together until the day of. It's an honor to be invited to someone's wedding and the invitation is something of a gift I've been given.
Your invitation sets the stage and tone for your wedding and reception. If more of a casual event, I probably wouldn't include it. If more formal/church wedding I definitely would. I personally like the tissue inserts... but then, I know what they're for and the purpose behind them and the history (as now you do too LOL)
Basically, it comes down to what your invitation suit "look" is and the tone/style of your wedding, on whether you use something or not.
Another paper used of late is a transparent/translucent vellum instead of tissue paper. This is a heartier paper. Thicker and heavier even tho translucent. It's popularity came about with more and more brides creating their own invitations.
It's typically used with an invitation that is embellished with raised items such as ribbons, rhinestones, multiple layers. What the vellum will do is help protect the stones, bows, ribbon etc from moving or getting damaged in mailing. IE it helps protect the surface of the invite from moving around thus hopefully arriving to its recipient as it was originally created. Hey DYI'ers... you put a lot of work into creating that unique one-of-a-kind invite - don't you want to make sure the person who gets it see's it as you made it? Not with the bow crooked or that rhinestone moved over to where it covers a word? You bet you do!
Making you're own invites or if your invites didn't come with tissue/vellum and you want to use it? There are sites on Etsy where you can buy both items cut to size in all sorts of colors. Just search using "wedding tissue" and you'll find them. Vellum is more expensive, but considering the work you put into your creation, worth it IMO... tissue is averaging around $5 for 50 sheets. Again, worth it IMO. Can you buy tissue that's typically used in wrapping paper? Of course, but then you need to hand cut it, and with it being such a light weight paper, and if you don't have a paper cutter - to do so would be tedious, and you've got enough on your plate.
Next: HOW is it all put together now that you're using it?
Simple version: One sheet goes on top of the invitation... then on top of that you'll put any other inserts (maps, separate reception card, special instructs) with your RSVP being the last item on top. (Slide the rsvp card under the rsvp envelope flap - NOT inside the rsvp envelope!). Your stack (your wedding invitation suit) is then ready to slid into the inner envelope face up. You do NOT seal the inner envelope, you DO hand write the name(s) of the recipient on the front. Then slide the entire package into the outer envelope with the name facing up towards the back flap so they see their name when opening and pull it out... seal the outer envelope and mail that bad boy out!! Note: make sure the RSVP envelope is addressed to your home and has a stamp on it... have your outer envelope addressed and stamped as well before starting the assembly process... lastly, make sure the name on the inner envelope and outer envelope match LOL !! Sounds like a lot, but the process goes really fast. Remember, this is, in essence, a very special gift you're mailing someone!
Card style invite: one that opens up... you slide the inserts INSIDE the invitation. The card itself protects the inserts...tissue on top of the invite before sliding into inner envelope.
It is acceptable to use a sheet of tissue between all layers of invitation suit as well. IE on top of the invitation, then place reception card, tissue, map, tissue, rsvp... you get the idea. This method is rarely used however, but again, if all items are subject to possible smudge, movement etc... I'd go with it.
Pocket invitations: should always use a sheet of tissue/vellum on top of invitation wording before being folded up and mailed. Tissue not used in the insert area.
I hope this was informative and helps save someone from spending excessive amount of time internet searching like I did :-)
Side note: my invitation suit? I'm having a golden age of piracy/rococo styled wedding. (Think Marie Antoinette goes rogue pirate lol) Invitations are based from 17th/18th century style. As I wanted a certain authenticity to them, thus a DYI project using aged parchment papers and envelopes with custom made stamps for each segment. Printed on my inkjet printer at home, the ink does want to smudge if it gets damp on the parchment. The save-the-date is a small card style, with a burnt vellum overlay on the front... save the date info inside. The invitation suit includes a card style invite with printing on both inside and out as well as front and back... a folded map using an actual photo of the area we live as the background aged and embellished as would have been the style then, with instructions on wedding/reception or reception only depending on who was invited to what, hotel info and dress code.... and of course, an rsvp. I used 2 sheets of tissue to protect the invite (inside and front) in a color matching the aged parchment. Cost to mail: 91 cents per invite.