How come no-one makes continuous fibre synthetic fill with a reinforcing ripstop pattern so that its is strong enough to use as a blanket on its own:

it would not then need quilted to the sleeping bag outer reducing cost and making it longer lasting,

or it could then be used within a windproof (vapour) bivi (as a blanket) with out the overhead of a shell to be quilted to. Also, any rips would be visible and repairable.

Also, there would perhaps be a bigger boundary air layer between wadding sheets increasing warmth of bag for no extra weight.


Is there a UK source for Polarguard 3D/Delta?

In answer to your question; probably because there is no market for such a product. The vast majority of people are perfectly happy with using a standard sleeping bag, at least I presume they are. Selling the sleeping bag minus its shell doesn't seem all that glamorous. It's an interesting idea though.

I imagine the problem could be that a reinforced ripstop pattern would prevent the fill lofting. It would need to be very strong as you can pull synthetic fill apart quite easily. You can get sleeping bags with the fill only attached at the ends and not quilted. The problem here seems to be that over time the fill clumps in some areas, leaving others thin.

Continuous wadding (eg cheap presumably non-hollow stuff from local shops) seems strong in one direction so perhaps could be strengthened by sewing two layers together at edges but with 'grain' at right angles.

Presumably Polarguard 3D would be the same (but I cant find a UK source.