• Global Site
  • About DIC
  • Business
  • IR
  • Sustainability
  • R&D


DAITAC WS#8402 Series Waterproof Double-coated Adhesive Tape for Mobile Devices

Cellular phones have a number of varied functions and have become an indispensible presence in our lives. They have used in many situations and their usage around water has become normal. In order to prevent water immersion accidents, Japanese cellular phone manufacturers have introduced cellular phones into the market given full-fledged waterproofing features (IPX7, 8). DIC was among the first to develop and launch a waterproof double-coated adhesive tape that uses a special foam with a closed pore structure for the base material, an element which has become essential for adding waterproofing features to cellular phones.


  • Waterproof: Clears the JIS waterproofing standard (IPX7, 8) just by applying the tape
  • Impact resistance: Clears the six-side drop test
  • Die-cutting quality: Even though it is narrow parts, die-cutting is possible
  • Reworkability/reparability: Removable types also available


For securing panels, lenses, and parts in waterproof small electronic devices including cellular phones, digital cameras, netbooks, and LCD TVs


The WS#8402 Series is a waterproof double-coated adhesive tape constructed with a special acrylic-based adhesive layer on both sides of special thin foam with a closed pore structure.

WS#8402 Construction

Performance Tests

Waterproof test (IPX7)

The waterproof test IPX is a testing method specified by the Japan Industrial Standard (JIS). There are levels from IPX1 to 8. IPX7 and 8 are full-fledged waterproof. For IPX7, the condition for passing the test is water does not enter inside the cellular phone after the cellular phone or test specimen is left in 1 m deep water for 30 minutes. DIC WS#8402 can prevent the intrusion of water even when there is a level difference by smoothly conforming to that difference.

Items WS#8402 Competitor's product
Tape foam type Polyolefin (black/white) Acrylic
Tape thickness (μm) 200 250
Waterproof test
Flat surface Good Good
50 μm corrugated surface

Water resistance test WS#8402

The tape conforms to the irregularities caused by the spacer. No water intrusion.

Water resistance test, other company's product

The tape does not seal, water intrudes inside the specimen

Impact resistance test

Impact resistance test

The impact resistance test is an extremely important test for mobile devices like cellular phones. DIC has established our own testing method to evaluate shock resistance. As shown in the figure, impact resistance is evaluated using a Dupont impact tester. A 300 g load is dropped on a specimen made of an ABS plate and acrylic plate bonded by double-coated adhesive tape and the height where the specimen's acrylic plate separates is evaluated. The better the impact resistance, the higher the drop height becomes. DIC's WS#8402 possess superior impact resistance when compared to the competitor's product below 23°C and even below 0°C. Note: Over 50 cm means the specimen did not drop even exceeding the tester's maximum height of 50 cm.

  Test Atmosphere WS#8402 Competitor's product
Impact Resistance
(Drop Height)
23°C Over 50 cm 20 cm panel drop
0°C Over 50 cm 10 cm panel drop

Physical Properties Table

The test results are shown in the the physical properties table. The WS#84020 rework-compatible product is a type of adhesive tape with the same adhesive and waterproof performance of the standard product WS#8402, but it is easily removed during repair or rework.

Test Item Unit Rework-compatible
Standard WS#8402
Tape thickness* μm 200 200
180° peel strength (ABS) N/20 mm 15.0 15.0
Push strength (ABS) N/4 cm2 140 140
Holding power (70°C, 500 g/4 cm2) h 24< 24<
Impact resistance (ABS/load 300 g) cm Over 50 Over 50
Reworkability (after left 7 days at room temperature after application) - Good Fair
  • *A 150 μm tape thickness type is also available.


Maximum width: 980 mm, standard length: 20 m

For inquires related to these products
For inquires via the web Contact Form

Europe | HOME > DIC Products > Industrial Adhesive Tapes > Adhesive Tape for IT Devices > DAITAC WS#8402 Series Waterproof Double-coated Adhesive Tape for Mobile Devices