Plastics Historical Society

More Auction News from Carolyn

admin — Sun, 17 Oct 2010 19:35:21 +0000

Auction news over the summer: brown bakelite Ecko type AD 36 sold for £350 (£411). And more high prices for antique horn. C18 Indian curled horn powder flask, with ivory and some mother of pearl applied decopration carved with flowerheads, sold for £6,700 (£7880).

November is National Antiques Week. Many fairs are offering free entry for 2, including the Alexander palace Fair on 14th November. Details and downloadable the voucher on: www.nationalantiquesweek.co.uk

More Plastics at Auction

admin — Thu, 16 Sep 2010 14:25:13 +0000

AUCTION UPDATE: Ebena is still one of the most valuable plastic products. Recently saw a rectangular box with a cloud-like effect in blue and white for £220 asking prtice at a Fair. On Ebay, a round box in blue, green and gold with the classic cream coloured Egyptian style cat head finial sold this month for £204 plus postage. From Carolyn

Horn at £8,800 a pop!

admin — Fri, 13 Aug 2010 20:08:34 +0000

Lovers of pre-chemical plastics will be interested to hear about the sale of a rare 17th century horn shoe horn. 9 inches long, this engraved shoe horn sold for £8,800 plus buyer’s premium in a July auction in Ely. The horn was engraved all over, and included with a crown and Tudor rose image. An inscription around the edge states “Robart Mindum made this shooing horne for Mistress Blake Anno Domino 1612″. In terms of shape, you’d be hard pressed to spot the difference between this and the profusion of modern plastic shoe horns. Carolyn

Green Carvacraft Bookends

admin — Fri, 13 Aug 2010 19:07:04 +0000

I pair of very good condition green Carvacraft bookends have just sold on Ebay for £401, with over 20 bids. This reflects the rarity of green phonolic.catalin holding its fresh emerald colour.

Plastics at Auction

admin — Sun, 18 Jul 2010 00:03:03 +0000

PHS Committee Member Carolyn Clark tells me:
Plastics prices for the unusual and rare at auction have been holding their prices. Although the bakelite coffin failed to sell last year, other lots have achieved high prices. In a recent sale, the Master Incolor Cocktail Shaker in cream urea formaldehyde (incorrectly described as bakelite and carrying an estimate of £40-£60 in the catalogue) made £360, plus buyer’s premium.

Even the basic pieces can still attract a good price. A Carvacraft photo frame in butterscotch has just sold on Ebay for £123.25 following 18 bids and a calender in the same range for $177 (about £110).

Clear Vision?

admin — Thu, 22 Apr 2010 23:13:19 +0000

After a day in London for a PHS committee meeting and a look at the National Gallery followed by a wild evening with the local Rotary club for a St Georges day celebration last night I didn’t feel like blogging, but tonight I’m up for it. Having just had to remove my CIBA Vision “Dailies” soft one day contact lenses as they were uncomfortable after being in for14 hours, this is the plastics topic on my mind tonight. These lenses contain 31% nefilcon A hydrophilic polymer and 69% water according to the box, which is when you come to think of it quite an achievement to produce an optically accurate lens with such a high proportion of water in it. Luckily the box gives a clue to how this was achieved by mentioning that the product is patent protected by US 5508317.

A look in espacenet finds the abstract which can be consulted at http://v3.espacenet.com/publicationDetails/biblio?DB=EPODOC&adjacent=true&locale=en_EP&FT=D&date=19960416&CC=US&NR=5508317A&KC=A

this tells ust that the polymer is made by polymerisation of a prepolymer containing both ether and amine linkages and olefinic unsaturation, and is equivalent to EP0641806 which was granted for European countries. Interestingly the US examiner dealing with US 5508317 cited 20 prior patents during the examination process, which is an indication of how seriouslly patent examination is carried out in the modern age. Another interesting detail is that 35 later patents cited US 5508317, which shows that later inventions were maybe sparked by it.

Anyway as far as I’m concerned its a good product! Time for bed.

Canned Widgets

admin — Tue, 20 Apr 2010 20:59:34 +0000

On to my second blog after a pause while I was away in Paris and after that when my daughter was hogging the computer doing her essay for her college course. Anyway sitting here with a can of John Smith’s Extra Smooth, I wonder what on Earth I should blog about, then I remember the widget inside my can: a little plastic “thing” that causes the beer to foam and give it a creamy head. So I take a knife to my previous (empty) can and extract one to see what it looks like: it turns out to be a spherical ball about 3cm in diameter with an equatorial seam (like a table-tennis ball but a bit smaller); and with a conical depression in the base and a little nozzle formed at the top.

Looking at the patents database http://ep.espacenet.com, I decide to see if I can track it down to see how it works: there being no patent number on the can or on the widget. Searching in espacenet for “widget” draws a blank, so I look on the web in general and immediately pin down a Wikipedia article on “widget (beer)” which gives the first patent filed in the field, GB1266351. Looking at the 3 European classifications for this patent in espacenet I find that the classification B65D85/73 [containers etc..with means specially adapted for effervescing the liquids, e.g. for forming bubbles or beer head] seems to be for widgets, so I look in espacenet to see how many hits that classification gives: 844. Pausing for a comfort break and to get my last can of beer from the fridge I take another look at the can for any other clues, and am still sober enought to see that the beer was brewed by Scottish & Newcastle. Back to espacenet and a combination search for the classification and “scottish + newcastle” gives a nice 22 hits. Browsing through the hits shows a nice selection of widgits, some spherical and other assorted shapes GB2353265 looks a likely contender:

A device for inclusion in a pressurised beverage container for jetting gas into a beverage in the container upon opening the container comprises a housing (13,23) defining an internal chamber (30) provided with spaced lower and upper permanently open orifices (22,12). The internal chamber (30) is adapted to contain pressurised gas and a quantity of beverage. The upper orifice (12) is located above and the lower orifice (22) below the level of beverage in the device prior to firing of the device when the container is opened. The upper orifice (12) is in communication with the internal chamber through an upper standpipe (11) which, immediately prior to firing of the device, opens into the internal chamber (30) below the surface level of the beverage held within the container.; The device further comprises upper and lower well structures (15,25) on an external surface of the device in which are respectively located the upper and lower orifices (12,22), and in which, upon firing, beverage from within the device is forced towards the upper orifice (12) such that pressurised gas from the internal chamber (30) is preferentially expelled through the lower orifice (22) into the beverage in the container.

If you want to see the diagram you’ll have to check it out on espacenet:

http://v3.espacenet.com/publicationDetails/biblio?DB=EPODOC&adjacent=true&locale=en_EP&FT=D&date=20010221&CC=GB&NR=2353265A&KC=A

But just to make sure I look at the description of this patent and see that the closest prior art mentioned is EP833787 which is equivalent to WO9636545, both of which show something very similar.
But I’m still looking for a patent with the conical depression The ones I found have only a small 45 Degree chamfer, which might represent the same thing. Maybe S&N will give me a better analysis!

PHS Blogging

admin — Mon, 20 Jul 2009 07:13:10 +0000

This is my (Alan Wells) first PHS Blog after relaunching the PHS Website with the sponsorship of Roy Manns.

I will start off this blog as a PHS comittee member and will ask the other committee members to rotate as blogger in turn. I expect their blogging will be more exciting than mine.

I collect plastics articles that have a patent number on them, and I find it interesting to look up the original patent documents on www.ep.espacenet.com. I’m bidding on ebay for a couple of silver and bakelite items at present!

My most recent experience of plastics was in taking the dog for a walk: I find that the plastic bags used for mailing periodicals such as New Scientist make ideal pooper-scoopers if you take care in opening them at the top.