SHFE natural rubber front-month closed at Y19,580/t, giving back 0.53% on the day. Butadiene rubber front-month moved the other way, up 0.58% to Y16,455/t. The NR-BR gap compressed from the Y3,800-4,450 band seen last week to Y3,125 - the tightest in two weeks.

The gap matters on a tire compounder's formula sheet. Natural rubber has always carried a premium over butadiene rubber; the wider that premium, the more incentive to load butadiene and trim natural rubber to hold down the bill of materials. Today's compression removes part of that penalty, letting compounders lift the natural-rubber blend ratio without a visible hit to input cost.

For bonded-warehouse players this is a lock-the-cargo signal. A narrowing NR-BR gap often sits alongside downstream restocking; when the screen trades at a discount, parking the rubber in a bonded warehouse receipt captures the spread repair and, through a T+0 pledge against that receipt, keeps working capital turning. The NR-BR line today is less about who rallied hard and more about a structure shifting under the surface.