Why are ironing instructions on cotton shirts inconsistent?

June 22, 2009 7:48 PM

Why do different pure cotton shirts suggest that they be ironed at very different temperatures?

I have 100% cotton shirts with labels that say they should be ironed at one dot (110°c), others that say two dots (150°c) and others three dots (200°c). Why such a range of suggestions for (seemingly) identical fabrics?

Note that I am not asking what temperature I should iron cotton at in general - please don't derail. I am an experienced and capable ironer and am only asking about this discrepancy in labelling!

posted by Busy Old Fool to clothing, beauty, & fashion (9 comments total)

Sturdier, thicker cottons (denim, for example) should be ironed at higher temps than more delicate cotton fabrics. Is the three dot shirt thicker than the one dot shirt?
posted by amro at 8:03 PM on June 22

There may be interfacings (internal layers that add a slight stiffness in places like cuffs, collar and front placket) in some of the garments that can't take such high heat. Sometimes iron-on interfacings are used, and high temperatures can melt the glue and make it soak into the adjacent fabric. (Most factory-made garments use sew-in rather than iron-on interfacings, though.)
posted by Quietgal at 8:10 PM on June 22

In addition to the above:

Care labels in general do tend to be somewhat conservative, probably for liability reasons--the manufacturer doesn't want to handle a raft of customers upset about broken buttons or other damage, so they minimize the possibility by recommending the lightest possible touch.

This is why things that are logically perfectly washable often say "Dry Clean Only".

As an experienced ironer, you can use your best judgment. Due to possible other circumstances, like those Quietgal suggests, you can test an inconspicuous area of the garment (inside facings, the reverse side of a button placket) if you're not sure.
posted by padraigin at 8:39 PM on June 22

Another possibility is the thread. 100% cotton is the fabric, but thread is usually a blend. The blends sometimes don't take heat very well and either melt or deform radically when exposed to heat. Other possibilities are that the weave of the thread

Note: I know nofink about textiles; I just use a lot of "reclaimed" fabric to sew things for friends (i.e. dog beds out of a dog owner's old flannel shirt) and repair a lot of my own clothing, and I've made some amazing screw-ups.
posted by SpecialK at 9:08 PM on June 22

Oops. Read before posting.

"Other possibilities are that the weave of the thread" ... is one that will contract when the fiber expands or contracts, or the weave of the fabric is such that the thread expanding or contracting will ruin the fabric.
posted by SpecialK at 9:09 PM on June 22

I just bought some 100% Cotton Non-Iron Shirts. they feel kinda polysterish though. I assume the cotton was treated with some Chemical. But is still 'Cotton' apparently.

Are these items all of similar weights and thread counts?
posted by mary8nne at 6:07 AM on June 23

Another possibility is that the shirts have been treated in some way (wrinkle or stain resistance, for example), and the instructions are intended to preserve that treatment rather than the cotton fabric itself.
posted by oblique red at 8:24 AM on June 23

I write care labels for a major retailer and I'm getting a big kick out of these answers. Seriously, there are dozens of reasons. 1) ignorance by the manufacturer. 2) excessive caution by the mfr. 3) interlinings, embroidery, lace or buttons. 4) heat sensitive dyes. 5) resin or plastic surface sprayed on the fabric-- no iron, no stain, glossy etc.

Good advice to test inconspicuous area and look out for cuffs, collars, front plackets (where you would find interlining) and any trims which might have different fabric content.
posted by ohshenandoah at 3:54 PM on June 23

Thanks, all! I imagine that there are a combination of the factors above in play, though I'm not expert enough to figure out which ones in any individual case.
posted by Busy Old Fool at 1:14 AM on July 13