Coaster with I love You message that shown in sunshine

A unique present for your loved one which is useful and additionally holds a secret love message that can be revealed by the help of light.
If you direct the punched side of the coaster towards the sun and rotate is correctly then the I love U text will scroll through the front/top side of the coaster. You can also reveal the text at lamp light if you keep a distance from the lamp to ensure more or less parallel rays reaching the back side of the coaster.
The secret declaration of love is invisible while the coaster is used normally.
There are two models in the set one with filled heart between the I and U letters and one with empty heart, so you can choose according to your preference.
If you use glow in the dark PLA for the first few layers (the top or canvas side of the coaster) then the coaster is even more useful because your loved one can find her/his glass during the night.
Have fun! ;-)

It is important to use semi transparent material at least for the printing of the canvas of the coaster otherwise the sun cannot shine through and you will not see the text. For example gembird yellow filament is perfect but a black color will not work as a canvas. The model is placed upside down for easier and nicer printing.
I reached the best result for the canvas, when I printed the first 3 layers with glow in the dark PLA, then paused the print changed the PLA and used one layer white and the rest can be printed with almost anything you prefer, you can use black PLA for better contrast for example.
I set 210 °C for the printing head and 65 °C for the bed on my AnyCubic Kobra. The layer thickness was 0.2mm and the nozzle had the standard 0.4mm in diameter. The printing speed was 45 mm/s. There is no need to use supports or printing for adhesion. The coaster releases the plate as soon as the plate cools down, no need to use extra force the get the print in place coaster. It took a bit more than 5 hours to print one coaster. The model's suggested / default diameter is near to 95 mm, its thickness is arount 11.6mm. The infill I used was 15%.
If you accidentally used a less transparent material for the canvas then you can still use a sandpaper to thin the canvas and make it more transparent (I tried it with fluorescent blue PLA).