3M 7961MP

Product Data Sheet

Updated : July 2000

Supersedes: November 1994

Physical Properties

Not for specification purposes

LinerAdhesiveCarrierAdhesiveLinerShelf Life

0.10mm 58# Polycoated Kraft

0.05mm #200 “High Performance” Acrylic0.178mm Polyester Film

0.05mm #200 “High Performance” Acrylic0.10mm 58# Polycoated Kraft

12 months from date of manufacture by 3M if stored atroom temperature condition in cool, dry and sun protectedroom.

Features:

• Long term, environmentally stable bond

• High cohesive strength to withstand repeated stresses from switch activation.

• Excellent temperature, humidity, and chemical resistance.

• High bond strength to high surface energy plastics such as polyester and

polycarbonate.

Applications• Spacer for membrane switch/keyboard circuits.

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Date : July 2000

Membrane Switch Spacer7961MP

Properties andPerformance

Not for specification purposes

Temperature Range

Low : -40°F (-40C)

High Long Term (days/weeks) : 250°F (121°C).High Short Term (minutes/hours) : 300°F (149°C).Solvent resistance is excellent when this product is

properly applied to impervious materials. The adhesiveresists softening through edge contact with mild acids,alkalis, oil, gasoline, Kerosene, JP-4 fuel and many othersolvents.

Not recommended for total immersion.

Chemical Resistance

Dielectric Strength

(ASTM D149)

1.5 KV/mil2.5 x 1014 ohms1.1 x 10 ohm-cm1.1 x 1014 ohms/square

No adverse effect on the bond after exposure to 100%Relative Humidity at 100°F.

The bond strength of Scotch #200 Hi-Performance Acrylicadhesive increases as a function of time andtemperature.

Adhesive is very resistant to oxidisation and ozone whenexposed to air or sunlight (U.V.).

15Insulation Resistance

(ASTM P257)

Volume Resistivity

(ASTM D257)

Surface Resistivity

(ASTM D257)

Moisture & HumidityResistanceBond Build Up

U.V. Resistance

Physical Properties

Not for specification purposes

180° Peel12”/minute 1 mil polyester to stainless steel (ASTM D903)

11.4 N/10mm

3M test 90° peel 12”/minute 8 mil aluminium to various surfaces

72 hour Dwell N/10mm

Ultimate Bond N/10mm

7.48.07.013.410.0

Stainless SteelEpoxyPolyester

PolycarbonateABS

11.48.87.410.810.2

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Date : July 2000

Membrane Switch Spacer7961MP

Application Techniques

• Bond strength is dependent upon the amount of adhesive surface contact

developed. Firm application pressure develops better adhesive contact and thusimproves bond strength.

• To obtain optimum adhesion, the bonding surfaces must be clean, dry and smooth.

Some typical surface cleaning solvents are isopropyl alcohol or heptane. Useproper safety precautions for handling solvents.

• Ideal tape application temperature range is 70°F to 100°F.

• Application to surfaces at temperatures below 50°F (10°C) is not recommended

because the adhesive becomes too firm to adhere readily. However, once properlyapplied, low temperature holding is generally satisfactory.

3M is a trademark of the 3M Company.

Values presented have been determined by standard test methods and are average values not to be used for specification purposes.

Our recommendations on the use of our products are based on tests believed to be reliable but we would ask that you conduct your own tests todetermine their suitability for your applications.

This is because 3M cannot accept any responsibility or liability direct or consequential for loss or damage caused as a result of ourrecommendations.

Tapes & Adhesives Group3M United Kingdom PLC3M House, PO Box 1,Market Place,

Bracknell, Berkshire,RG12 1JU

Product Information :Tel 0870 60 800 50Fax 0870 60 700 99

3M Ireland

3M House, Adelphi Centre,Upper Georges Street,

Dun Laoghaire, Co. Dublin,Ireland

© 3M United Kingdom PLC 2000

Customer Service :Tel (01) 280 3555Fax (01) 280 3509