If one asked a sample of people who lived through the period what they thought of nylon shirts I'd wager either "hot" or "sweaty" or both featured high in the list of responses.
It has to be said that there is some truth in this - and indeed sometimes that can be the part of the attraction. It's a simple consequence of the nature of the
material which is isn't capable of absorbing as much water as cotton, wool and other common natural fibres. So less absorbent, but not entirely impervious, it's a matter of degree and the experience of wearing nylon is in part the perception of difference if one is accustomed to fabrics with different characteristics.
However the perception was enough of a marketing problem for attempts to be made to counteract the stick to the skin experience we're probably all familiar with and as a result there can be considerable variations between different nylon shirtings.
I would guess this to be an early example of nylon in retail; it is a tunic shirt - intended to be used with a separate stiff or semi-stiff collar - made by Harvie and Hudson and bearing the words "Pure Porous Nylon" embroidered in copper plate style on the label.
H&H was founded in 1949 so that puts an earliest possible date on the shirt while the expected clientel for such a company and the distinctly posh presentation suggests that it is probably not later than the mid Sixties.
The other indicator is that this fabric is woven rather than knitted. In texture it's the most un-nylon-like of the vintage nylon shirts I've seen any my guess is that it would not have given the stickies, especially to a sedate gentleman in stud collar, morning coat and bowler hat walking about the City.
Right is a sample of a knitted fabric from a very basic shirt, the sort of item one might have expected from the Co-Op or a market stall. This is knitted and the thread far finer than the first example. The horizontal and less apparent texture is not created by threads but is an artefact of the knitting process. To the touch it is very smooth and it's a fine example of the the sort of nylon that will readily stick to perspiring skin.
This is the inner surface of a
Mark Caine (see the Bobby Moore fashion shirts) pale blue uniform style shirt.
The outer side is smooth to the touch and on close examination achieves its colour by mixing two different shades of pale blue.
On the reverse the knitting process has produced this very distinct texture with the darker thread standing proud. I can say from experience that in stopping the stickies its a very effective technique.
It's neither the colour nor the fabric mix of the British service issue shirts. The first one I had lacked a label and the closest match for either the colour or the style was USAF uniform. However finding one with the label intact showed that this could not be correct so if anyone knows who they were produced for I'd love to know. There are button-down epaulette tabs rather than loops on the shoulder and in addition to the size there is "M.P." printed inside the collar
This is a Marks and Spencer "barcode" and as can be seen the apparent striped pattern is not produced by varicoloured thread but by different densities in the knit produced by varying the tension on the machines. The same effect can be produced in larger scale very easily on domestic wool knitting machines and with difficulty by a highly skilled hand knitter.
The barcode was ubiquitous when I was a kid, back in 1974 one of the Sixth Formers had a different coloured one for each day of the week. But my first nylon shirt was smooth, the classic speckle-grey of mixed black, grey and white threads while the second was plain white and entirely smooth (I'd love to find examples of either).
I also have Marks & Sparks nylon plain fabric in adult size collared and tunic shirts but the barcode was what remained on the shelves until finally M&S gave up nylon shirts entirely. The patterning was not unique to M&S so it's my assumption that there was some advantage to it other than being a distinctive style and suppose that to be the comfort factor. It would be fascinating if there was indeed a marketing reason but I do not recall anything like the adverts that
John has on his blog for M&S. Did they rely entirely on reputation and so saw no need to advertise?
This technique was used to extreme by Van Heusen with looser knits making fabrics that might even be termed aerated.
This last example baffles me slightly. There is both a slightly raised texture to the knit as seen before but also an even higher raised thread seen running horizontally in the picture but actually vertically as the sleeves and body have been cut which doesn't seem to be easily explained by the knitting process. It's almost like a rip-stop but so fine that one wonders if it would have been effective as such.
The shirt itself is part of a Shell petrol station attendants uniform so I suppose it possible that the intention was durability rather than comfort.
In other uses of nylon attempts were made to mitigate the perceived problem including the heresy of "brushed nylon" for sheets which I can't quite bring myself to photograph as it quite ruins the point!
More sophisticated treatments with similar effect are used in modern nylon hiking clothes which are valued for being lighter than polyester and either chosen over cotton because being less absorbent they remain light when wet. Du pont's Supplex Nylon is advertised as wicking away moisture (which is to say sweat) and so being comfortable but of course all these efforts make a garment decidedly unlike the vintage nylon shirt.
Back to the matter of perception I've worn nylon shirts in Sicily having an unprecedented spring heatwave and in North Carolina on the edge of an autumnal tropical storm. Yes, the feel is different from a cotton or polycotton shirt and one is aware of it but I don't often feel it to be discomfort, certainly never to the extent of wishing to change shirts, and any breeze seems to cool through a nylon shirt more readily than natural fibres, even silk. I'd have no hesitation ignoring modern innovations and wearing
Another facet of the modern use of nylon is that it provides considerably greater protection from ultra-violet light than cotton of similar weight - this is the main reason behind the "bright" whiteness of white nylon shirts and the vibrancy of many nylon colour dyes. Wear a white nylon shirt to an old fashioned disco with UV "black" lights and you'll glow! Alas UV over the very long term can damage nylon and occasionally vintage finds will show yellowing, often where packaging has been damaging exposing the contents to the air, direct light or both. Keep your shirts in the dark!
One last thought. I've noticed among nylon shirt aficionados a certain tendency to bearishness. I've no idea if it's proportionately larger than the population as as whole but certainly it occurs to me that body hair would do much to mitigate any stickiness from perspiration. I could never be called a bear with even the most outré imagination and a good dollop of irony. What little hair there is I often shave entirely. Nylon on a truly naked skin is delicious.
Amongst others one of the sartorial things I like is a detachable collar. 
So here's the conundrum: how to find a detachable collar that meets the criteria of synthetic?
The only nylon detachable collars that I have found came with 2 mail-order shirts by Holroyd and Cooper, shirtmakers of Whitworth Street, Manchester. The subject of this 2005 Yahoo Groups post and this photoset on my old site.
I bought a Van Heusen nylon tunic shirt and the seller had included two detachable collars.
So, down the side here are some photos — in what has become the traditional manner — showing the surprise finds from packet to body. I'm not sure what a blog visitor can do with the pictures: I've uploaded them in versions large enough to see the weave of the fabric in many cases, but set them small to display reasonably without overwhelming the page. So please let me know if you can or cannot access the large versions for viewing. 
