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Application Techniques

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Clean: Most substrates are best prepared by cleaning with a 50:50 mixture of isopropyl alcohol (IPA*) and water prior to

applying 3M™ VHB™ Tapes.

Exceptions to the general procedure that may require additional surface preparation include:

•

Heavy Oils: A degreaser or solvent-based cleaner may be required to remove heavy oil or grease from a surface and

should be followed by cleaning with IPA/water.

•

Abrasion: Abrading a surface, followed by cleaning with IPA/water, can remove heavy dirt or oxidation and can

increase surface area to improve adhesion.

•

Adhesion Promoters: Priming a surface can significantly improve initial and ultimate adhesion to many materials

such as plastics and paints.

•

Porous surfaces: Most porous and fibered materials such as wood, particleboard, concrete, etc. need to be sealed

to provide a unified surface.

•

Unique Materials: Special surface preparation may be needed for glass and glass-like materials, copper and copper

containing metals, and plastics or rubber that contain components that migrate (e.g. plasticizers).

Refer to 3M Technical Bulletin “Surface Preparation for 3M™ VHB™ Tape Applications” for additional details and

suggestions. (70-0704-8701-5)

*Note: These cleaner solutions contain greater than 250 g/l of volatile organic compounds (VOC). Please consult your

local Air Quality Regulations to be sure the cleaner is compliant. When using solvents, be sure to follow the

manufacturer’s precautions and directions for use when handling such materials.

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Pressure: Bond strength is dependent upon the amount of adhesive-to-surface contact developed. Firm application

pressure develops better adhesive contact and helps improve bond strength. Typically, good surface contact can be

attained by applying enough pressure to insure that the tape experiences approximately 15 psi (100 kPa) pressure. Either

roller or platen pressure can be used. Note that rigid surfaces may require 2 or 3 times that much pressure to make the

tape experience 15 psi.

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Temperature: Ideal application temperature range is 70°F to 100°F (21°C to 38°C). Pressure sensitive adhesives use

viscous flow to achieve substrate contact area. Minimum suggested application temperatures:

• 50°F (10°C): 3M™ VHB™ Tapes 5952 and RP families.

• 60°F (15°C): 3M™ VHB™ Tape 4941 family.

Note: Initial tape application to surfaces at temperatures below these suggested minimums is not recommended

because the adhesive becomes too firm to adhere readily. However, once properly applied, low temperature

holding is generally satisfactory.

To obtain good performance with all 3M™ VHB™ Tapes, it is important to ensure that the surfaces are dry and free of condensed moisture.

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Time: After application, the bond strength will increase as the adhesive flows onto

the surface (also referred to as “wet out”). At room temperature approximately

50% of ultimate bond strength will be achieved after 20 minutes, 90% after

24 hours and 100% after 72 hours. This flow is faster at higher temperatures

and slower at lower temperatures. Ultimate bond strength can be achieved more

quickly (and in some cases bond strength can be increased) by exposure of the

bond to elevated temperatures (e.g. 150°F [66°C] for 1 hour). This can provide

better adhesive wetout onto the substrates. Abrasion of the surfaces or the use of

primers/ adhesion promoters can also have the effect of increasing bond strength

and achieving ultimate bond strength more quickly.

100

80

60

40

20

0

20 MIN

1 HOUR

24 HOURS

72 HOURS

150°F or ABRADE

50°F

ROOM TEMP

PERCENT OF FULL BOND

Bond Typical Build vs. Time