[00:44.64]TUTOR:OK, Jim.
[00:45.83]You wanted to see me about your textile design project.
[00:50.00]JIM:That’s right.
[00:50.72]I’ve been looking at how a range of natural dyes can be used to colour fabrics like cotton and wool.
[00:57.07]TUTOR:Why did you choose that topic?
[00:59.39]JIM:Well, I got a lot of useful ideas from the museum, you know, at that exhibition of textiles.
[01:05.21]But I've always been interested in anything to do with colour.
[01:08.42]Years ago, I went to a carpet shop with my parents when we were on holiday in Turkey, and I remember all the amazing colours.
[01:16.18]TUTOR:They might not all have been natural dyes.
[01:19.18]JIM:Maybe not, but for the project I decided to follow it up.
[01:23.32]And I found a great book about a botanic garden in California that specialises in plants used for dyes.
[01:30.40]TUTOR:OK.So, in your project, you had to include a practical investigation.
[01:35.78]JIM:Yeah.At first I couldn't decide on my variables.
[01:39.25]I was going to just look at one type of fibre for example, like cotton...
[01:44.18]TUTOR:...and see how different types of dyes affected it?
[01:47.03]Yes. Then I decided to include others as well, so looked at cotton and wool and nylon.
[01:53.93]TUTOR:With just one type of dye?
[01:55.81]JIM:Various types, including some that weren't natural, for comparison.
[01:59.69]TUTOR:OK.
[02:00.30]JIM:So, I did the experiments last week.
[02:03.16]I used some ready-made natural dyes, I found a website which supplied them, they came in just a few days, but I also made some of my own.
[02:12.71]TUTOR:That must have taken quite a bit of time.
[02:14.97]JIM:Yes, I'd thought it'd just be a matter of a teaspoon or so of dye, and actually that wasn't the case at all.
[02:21.92]Like I was using one vegetable, beetroot for a red dye and I lad to chop up a whole pile of it.
[02:28.38]So it all took longer than I'd expected.
[02:31.02]TUTOR:One possibility is to use food colourings.
[02:34.36]JIM:I did use one.
[02:35.25]That was a yellow dye, an artificial one.
[02:37.83]TUTOR:Tartrazine?
[02:39.01]JIM:Yeah.I used it on cotton first.
[02:41.93]It came out a great colour, but when I rinsed the material the colour just washed away.
[02:46.52]I'd been going to try it out on nylon, but I abandoned that idea.
[02:50.81]TUTOR:Were you worried about health issues?
[02:53.36]JIM:I 'd thought if it's a legal food colouring, it must be safe.
[02:56.76]TUTOR:Well, it can occasionally cause allergic reactions, I believe.
[03:46.09]TUTOR:So what natural dyes did you look at?
[03:49.53]JIM:Well, one was turmeric.
[03:51.86]The colour's great, it's a really strong yellow.
[03:54.96]It's generally used in dishes like curry.
[03:57.82]TUTOR:It's meant to be quite good for your health when eaten, but you might find it's not permanent when it's used as a dye - a few washes, and it's gone.
[04:06.29]JIM:Right.
[04:07.35]I used beetroot as a dye for wool.
[04:10.18]When I chop up beetroot to eat I always end up with bright red hands, but the wool ended up just a sort of watery cream shade.Disappointing.
[04:18.74]TUTOR:There’s a natural dye called Tyrian purple.Have you heard of that?
[04:22.41]JIM:Yes.
[04:24.20]It comes from a shellfish and it was worn in ancient times but only by important people as it was so rare.
[04:30.24]I didn't use it.
[04:31.65]TUTOR:It fell out of use centuries ago, though one researcher managed to get hold of some recently.
[04:36.68]But that shade of purple can be produced by chemical dyes nowadays.
[04:40.91]Did you use any black dyes?
[04:42.78]JIM:Logwood.
[04:43.67]That was quite complicated.
[04:45.71]I had to prepare the fabric so the dye would take.
[04:48.64]TUTOR:I hope you were careful to wear gloves.
[04:50.38]JIM:Yes. I know the danger with that dye.
[04:52.33]TUTOR:Good. It can be extremely dangerous if it's ingested.
[04:55.07]Now, presumably you had a look at an insect-based dye?Like cochineal, for example?
[05:00.49]JIM:Yes.I didn't actually make that, I didn't have time to start crushing up insects to get the red colour and anyway they're not available here, but I managed to get the dye quite easily from a website.
[05:12.81]But it cost a fortune.
[05:14.12]I can see why it's generally just used in cooking, and in small quantities.
[05:18.95]TUTOR:Yes, it's very effective, but that's precisely why it's not used as a dye.
[05:23.34]JIM:I also read about using metal oxide.
[05:26.21]Apparently you can allow iron to rust while it's in contact with the fabric, and that colours it.
[05:32.34]TUTOR:Yes, that works well for dying cotton.
[05:34.67]But you have to be careful as the metal can actually affect the fabric and so you can't expect to get a lot of wear out of fabrics treated in this way.
[05:42.19]And the colours are quite subtle, not everyone likes them.
[05:46.37]Anyway, it looks as if you've done a lot of work...
What problem is identified with each of the following natural dyes?
Choose SIX answers from the box and write the correct letter, A—H, next to
Questions 25-30.
Natural dyes
25 turmeric 25
26 beetroot 26
27 Tyrian purple 27
28 logwood 28
29 cochineal 29
30 metal oxide 30