Jesus on the rear window


#1

Why does Jesus appear on the rear window of the listener’s Subaru whenever it fogs up?


#2

Somebody (I don’t know who) sells large window decals of Jesus for applying to car windows. Obviously this listener’s used car once had such a decal, which was removed before it was sold to her. Some of the adhesive remains on the window–not enough to see unless the window fogs up. A product like Goo Gone might remove the latent adhesive, but then it might remove the rear window defogger too. I’d suggest she live with it, and get whatever mileage (pun intended) she can from it.


#3

It’s a lot neater than a St. Christopher’s statue on your dash board.


#4

A dear friend of mine has an indelible university etched in his back window that is only viewable early in the morning, when it rains, or any time the windows are frosty or foggy. We have tried everything to remove it, and have come to conclusion that between the sun, and the tinting of the sticker and the window, that its rather akin to taking pictures of paintings.


#5

This should go on EBAY for a lot more than a grilled cheese sandwich!

Or she could take it on tour, a pilgrimage that comes to a place near you.

By the way, who exactly decided what Jesus looks like, an artist? Perhaps we found a use for art history majors, religious research.


#6

“By the way, who exactly decided what Jesus looks like, an artist? Perhaps we found a use for art history majors, religious research.”

Good point, about 1500 years later some renaissance painters apparently decided he looked like a typical white european guy, amazing.


#7

I would say the same thing. That the last owner before Kristy had it, had a window decal of Jesus on it . Like part of what the last comment said, I’d drive it for as long as it will go ! Let me add since you will have Jesus with you , you’ll probually be able to drive it for as long as it take’s Jesus to come back in real life for us !


#8

I’ve heard that The Rapture is just around the corner. Does that mean the Subie is in big trouble? No matter. Who’s gonna drive it after the apocalypse anyway? 8^o


#9

Yes, I think you’ve got it, basically. A short lecture to fill in a little detail on the decal thing. At least, it’s a hypothesis:

Manufacturers of roll tape and other adhesives apply a releasing agent to their product. For instance, in the case of a roll of tape, they’ll apply adhesive to one side of a web (film), and apply releasing agent to the other side, and then roll this laminated film up into a roll. Then they slice it and package it and ship it. The purpose of the releasing agent is so that it doesn’t stick too itself TOO well. They want you to be able to unroll the stuff. You might have noticed that sometimes when you’re in a stingey mood you’ll buy one of those cheap rolls of tape–either transparent tape or masking tape. Then when you get it home and try to use it you find that you can’t unroll the stuff without tearing. Why? Probably one reason is cheap plastic, but another is that these cheapo operations skimp on the releasing agent or use an inferior grade one. So the roll sticks too well to itself. The releasing agent (at least the ones I’m familiar with) is often some type of chemical in the category called “siloxanes” or “silanes.” Think “silicone” and you have it about right. Something similar to that. Notice that silicone has some funny properties to it? Like…you can’t wet it with water? That’s what we’re probably talking about here. You see, the thing about this releasing agent is that some quantity of it will transfer from the backside of the tape onto the sticky side. When you unroll it to use it, you’re getting tape that is mostly adhesive on the sticky side–but with a little silanes mixed in. And on the back side is a whole lot of silanes–but you don’t detect that because it is essentially a monolayer–on the order of a single molecule thick. Now, if something goes wrong in this process–such as, they used a cheap version of the silane–or they used one that doesn’t have the best compatibility with the plastic… or the tape gets old or gets overheated or frozen or…Anyway, something goes wrong and you get lots of silane transfer when you peel it apart (tape won’t stick well then) or you get none because you can’t get the dammed stuff to peel. Further considerations: with car stickers I’ve seen them use a couple of different kinds of adhesive. One is more expensive and also allows you to peel it off more easily later, when you want to. Good quality bumper-stickers are like this. When the campaign is over, you can peel the candidate’s name off your car. Cheap bumper-stickers use a cheaper adhesive and you can’t get the dammed thing off for love nor money. The point is, with things that you stick to your car, they like to use an adhesive that…what?..sticks really well! That way the sticker doesn’t go peeling off in the rain or when your kids pick at it out of boredom.

A similar thing applies with applique’s. You have a liner is stuck to the adhesive side, and you have to be able to peel the liner off.

SO…if you’re making some sticker for a car, and you’re using some adhesive that you want to stick REALLY WELL, how do you make the liner so’s the customer can peel it off? Put lots of silane releasing agent on it! You get lots of silane residue mixed in with the adhesive.

You stick the decal to your window. Later you peel it off. You can leave a considerable layer of siloxanes behind. This is not wettable. And it does funny things when frost forms.

Just so you know, siloxanes are one of the biggest pollutants we’ve got, and nobody knows about it. They’re everywhere. If you did a chemical analysis of just about any surface in your home, using high-zoot chemical analysis tools, you’ll almost always find siloxanes. Why? Siloxanes travel. They go everywhere. Just as an example, one time I had a chemical analysis done on one of my company’s products. (We were looking for contaminants that might explain some wettability problems we had). I had the product sample cleaned thoroughly in a plasma chamber–there was no way there could be any organic chemicals left on them after a cleaning like that. I put the samples in a special clean container that came out of a hermetically sealed package–this is a shipping container made specifically for the shipping of ultra-clean laboratory samples. I put the clean samples in the clean container and and…what?..Fastened it shut with scotch tape and shipped it off to a lab in California. A couple days later I get a phone call. “We’ve got a problem. You used scotch tape to fasten the container, and that means that your sample is likely to have silanes all over it. Do you want us to run the test anyway?” I say “Really? The silanes are going to get from the outside of the tape to the inside of the box?” “Yup. Happens all the time. Silanes migrate. They’re everywhere.” They did the chemical analysis and, sure enough, silanes were all over my previously pristine samples.

By the way, for the lady with Jesus on her window… it takes some pretty heavy-duty cleaners to get all the silanes off of a surface. Essentially you can’t do it without putting your car into a giant plasma chamber. But you might be able to get most of it off by scrubbing with some series of probably really nasty ones. If you know a chemist or chemical engineer, I’d ask them. The solvents that I know about that I might try, if it were me, I don’t want to tell you about, as you might hurt yourself.

Or, you might be able to keep Jesus as a conversation piece, and show off your knowledge of chemistry by telling people that he’s only a monolayer–a single molecule thick.


#10

Somebody (I don’t know who) sells large window decals of Jesus for applying to car windows. Obviously this listener’s used car once had such a decal, which was removed before it was sold to her. Some of the adhesive remains on the window–not enough to see unless the window fogs up.

That is is, and it was so obvious I could not believe the boys could not come up with the right answer.

I used to own a BMW that had some shipping/port of entry stuff stuck to the windshield at one time - under just certain fogging conditions these images would appear - scrubbing did not help, so I just lived with it. Heck, if I use a suction cup Garmin GPS window mount on any car I can see the “ghostly” image of the circle for a long time afterward under the right fogging conditions.

Dennis