Pyrex is not always borosilicate

[gmkcpa]

I just got my January 2011 issue of Consumer Reports magazine. On pg 44 is an article "Glass bakeware that shatters". Very very interesting! Without copying word-for-word, it says that American-made Pyrex is soda lime glass. It used to be boro, but boro is more expensive to make. On the other hand, European bakeware dishes are still made from boro.

The article gives a history of Pyrex, talks of a new formula, and on-and-on. If you are really into this topic, IMHO this issue is a must.

[JesterGlass]

After I destroyed my third "Pyrex" glass measuring bowl a few years ago, I was moved to research this. It sucks that they've completely devalued a great brand out of cheapness.

[earlbacher]

the "pyrex" brand was sold, and is used for a brand name now only... saw this last year or the year before, a lot of negative comments on the brand... people would use a baking dish to bring in food from the grill, and have the dish explode on them sitting on the table... i think the company should be sued for false advertising...

[menty666]

I heard this a while back, it's a shame what those idiots did to the good name.

[KEW]

Someone here posted an article a few months back. The change was made in 1941 or some such long ago time. (Heck, I wasn't even born!)

[pam]

They haven't changed the formula in over 60 years. At least that is what they say. It was also stated that most shattering is cause by thermal shock - sitting a hot out of the oven container on top of a wet granite counter, pouring liquid into a hot in the oven container, running cold water into a hot container. We al know this, no shock there. I had one shatter once when I dropped it on the terazzo floor.

[Polgarra]

They talked about this on the Morning news.

[dogsrlove]

So I guess saying "made out of Pyrex" isn't a good description when telling a layman about a bead. Is "scientific glass" a better term? Are beakers and flasks still made of the harder glass?

Vanessa

[JesterGlass]

"Borosilicate glass" would be the correct term.

[dogsrlove]

Originally Posted by JesterGlass

"Borosilicate glass" would be the correct term.

Oh yes, I always used the correct term, but when I'm met with a blank stare, I have to "dummy it down" into terms they understand. When I've said "Pyrex", their eyes light up and then they say "Ooooooooooooh".

I'm concerned with the brand "Pyrex" using soda-lime, that saying "Pyrex" would be misleading (even if we are using true Pyrex (boro)).

Vanessa

[Mr. Meker]

I say "Made out of the same glass as labware"

[Kalera]

In the last few years I've heard many, many more stories of Pyrex kitchenware spontaneously exploding under normal use conditions, and finally got rid of all of my Pyrex after it happened to me. I wasn't hurt, fortunately.

Perhaps they've been making it out of soft glass for 60 years, but something's changed.

[Nitadee]

I just tell folks it's the "Old Pyrex" that they might remember from their childhood and that Pyrex made all lab glass...that gets them to aha'ing
Nita

[menty666]

I'm more specific when I tell them, "Pyrex, like your trusty measuring cup" Those are usually fairly heat resistant.


I like the lab ware response.

[gmkcpa]

I just reread the Consumer article to address some of the points mentioned above. It seems like the major players are/were Corning, World Kitchen, Anchor Hocking and ARC International (French company that bought European rights from Corning in 1994). It also seems like each person you ask, no matter what company they are from, gives a different, partial answer to each question, if they answer it at all. Like politicians!

So I will continue to refer to my glass as 'boro' or 'borosilicate'. If anyone questions that I'll say that 'it's the strong glass, as opposed to soda-lime glass, which is the weak glass that they make exploding bakeware out of'. (No offense meant to the high COE glass workers.)

[Kalera]

I hope you're joking. Boro is not "stronger" than soft glass, it's harder and more resistant to thermal shock. It's also more brittle and prone to breaking when dropped.

Giving people the impression that soft glass art might explode isn't going to help anyone who does glasswork.

[Kalera]

I also find that either people are already aware of the difference between borosilicate and soda lime glass, or they don't really care. And why should they? They aren't going to cook with marbles.

[JesterGlass]

Originally Posted by Kalera

Giving people the impression that soft glass art might explode isn't going to help anyone who does glasswork.

I think we're talking about cookware, in which case, yes, it will explode.

[Bunyip]

I was under the impression that glass cookware was made from tempered glass? Tempered glass has improved strength and thermal properties, as well as the property of breaking into small bits rather than giant shards.

Prince Rupert's drops, anyone?

[menty666]

as someone who's had a pyrex casserole dish explode on the stove...no, it's not tempered.

[Kalera]

Originally Posted by JesterGlass

I think we're talking about cookware, in which case, yes, it will explode.

I said "art".

I was replying to gmkcpa's statement that

I will continue to refer to my glass as 'boro' or 'borosilicate'. If anyone questions that I'll say that 'it's the strong glass, as opposed to soda-lime glass, which is the weak glass that they make exploding bakeware out of

I don't think comparing soft-glass art to exploding bakeware is a very good idea. For anyone. It'll just scare people who don't understand the mechanics of it all away from buying art glass.

[Kalera]

Originally Posted by menty666

as someone who's had a pyrex casserole dish explode on the stove...no, it's not tempered.

It's not tempered, and I don't think it's even annealed properly anymore, or perhaps the glass they're using now is inherently unstable. I'll never have another piece of Pyrex in my kitchen unless it says "borosilicate" on the bottom.

[Kalera]

After hearing about exploding Pyrex in the last few years, I had two friends experience it within the same week. Not innocuous shattering... violent explosions. One was cut on his face and he wasn't even standing near the dish. It wasn't on the stove and fortunately it wasn't hot. This is a recent problem.

I will say that I wouldn't use the word "Pyrex" anywhere near any of my glasswork in a customer's hearing. I just wouldn't want any association at all with exploding glass, because I'd worry that connection would turn buyers off of glass artwork altogether, out of caution.

Here is an old but interesting article: http://www.consumeraffairs.com/news0...rex_panic.html

Follow-ups: http://www.consumeraffairs.com/news0.../08/pyrex.html
http://www.consumeraffairs.com/homeowners/pyrex.html

Pyrex, of course, has a HUGE counter-campaign trying to "debunk" these "rumors". I might even have believed them, until the number of people I know personally who have experienced exploding Pyrex increased beyond plausible deniability. Also, I have noted how newer Pyrex pieces I had were "flaking" long, pointed shards of glass in a way that cannot be accounted for by normal use.

[pjmarchwinds]

corning sold the name "pyrex"...pyrex brand cookware is not borosilcate.