Siser® Sub-Block Heat Transfer Vinyl 15"

Siser® EasyWeed® Sub Block exists to solve one specific, expensive problem: dye migration. Press ordinary HTV onto a sublimated jersey or a hot polyester and within a day the garment's dye bleeds up through your design — white turns pink, grey turns purple, and the order is scrap. Sub Block is engineered to stop that.

It is the thickest and most opaque HTV Siser makes, and it applies at just 265°F — low enough that you are not driving the garment's own dye into a gas phase while you press. Use it as a base layer under other HTV, or on its own.

Features

• Blocks dye migration — keeps sublimation ink from bleeding into your artwork.
• Maximum opacity — the thickest film in the Siser range.
• 265°F application — a low press temperature, which is itself part of how it controls migration.
• Layerable base — press other HTV on top for full-color work on problem garments.
• CPSIA certified for children's apparel.
• Two colors, White and Barcelona Yellow, 15" wide in 1 through 50 yard rolls.

Recommended Fabrics

• 100% Polyester
• Sublimated Polyester

Sub Block is built for the fabrics that cause trouble. On cotton or blends where migration isn't a risk, a standard EasyWeed is the better choice.

Cutter Settings

Cricut — Blade: Standard · Setting: Paper+

Silhouette Cameo — Blade: Standard, 2 · Material: Heat Transfer, Smooth · Speed: 8 · Force: 4

Brother ScanNCut — Blade: Standard, 2 · Cut Speed: 1 · Cut Pressure: 3

Roland GS/GX-24 — Blade: 45° · Gram-Force: 80–90 · Offset: .250 · Speed: 30 cm/s

Graphtec — Blade: 45° · Gram-Force: 8–9 · Tool: CB09+0 · Speed: 30 cm/s

Mimaki CG-60SR III — Blade: 45° · Gram-Force: 80 · Offset: 30 · Speed: 20–30 mm/s

This is thick material — expect to run more force than you would on standard EasyWeed. Always cut mirrored and test cut first.

Application Instructions

• Mirror, cut, and weed the design.
• Preheat the garment for 2–3 seconds.
• Cover with a heat transfer cover sheet or multipurpose paper.
• Press at 265°F / 130°C for 10–15 seconds using medium pressure.
• Peel the carrier hot or cold — either works.

Test press and then wash-test on the actual garment before running the order. Dye migration behaviour varies by dye lot, not just by fabric.

Care Instructions

• Wait 24 hours before the first wash.
• Machine wash cold, inside out, with a mild detergent.
• Tumble dry on a normal setting.
• Do not bleach and do not dry clean.

Colors and Sizes

• White and Barcelona Yellow
• 15" wide (14.75" actual)
• 1, 5, 10, 25, and 50 Yard rolls