You can use heat n bond patches they are great and they come on different sizes
There is a product called Patch Attach. It is in a little bottle attached to a card. It says that it is 'Permanent; Washable; Dry Cleanable; No Sewing; Fast & Easy; and Non-Toxic. You apply it on the back of the patch, let it dry, then cover with press cloth and iron it on the item. *4U & all
This is the problem. There was noway to get the surbace on this backpack smooth enough to iron. And I wasn't sure about ironing that plastic covered fabric? Ideas
I would try ironing with the tip of my iron. The instructions say that you score the plastic being careful not to cut through to expose the fabric. This is a really tough question.
I just finished some totes for some of my friends, I used the fusible heat activated webbing to adhere the embroidery to the tote, and I used some Tulip paintstitch, or some 3D paint to hide the border of the fabric and add some little dots, curlies,etc., and they look real pretty.I wish I could send you some pictures, but I'm to dumb to upload the projects.If you send me your email y could send you a picture.
Since it is a backpack and they don't get laundered as often as clothing how about that heat activated fabric fusion? I saw it at the fabric store today, it was like $2.50 a yd. You just make a outline of the patch on the fusion, cut it out and iron it on. I did a search at JoAnn's they have a velcro brand also, the one I saw was by the yd. can't recall the manufacturer maybe Pellen called Heat and Bond. Hope this helps * xoxox