LOCTITE 425
Harmonization Code : 3506.10.00.00 | Prepared glues and other prepared adhesives, not elsewhere specified or included; products suitable for use as glues or adhesives, put up for retail sale as glues or adhesives, not exceeding a net weight of 1 kg
Main features
- Fast Plated-Fastener Fixturing
- Low-Strength Serviceable Retention
- Pre- or Post-Applied Locking
Product Description
LOCTITE 425 is a dark-blue, low-viscosity, one-part cyanoacrylate adhesive for low-strength threadlocking and retaining on metal and plastic fasteners. It can be applied before or after assembly and cures with atmospheric moisture. On plated metal and plastic fasteners, fixture is achieved in less than two minutes, while full strength develops within 24 hours. The low-strength cured joint supports adjustment or disassembly rather than permanent locking. It is suited to tamperproofing screw heads and potentiometers and to serviceable fastener retention within the -54 to 85 deg C operating range.
Key features
- Pre- or post-applied locking: The low-viscosity liquid can be placed before assembly or wicked onto assembled fasteners.
- Fast plated-fastener fixture: Plated metal and plastic fasteners fixture in less than two minutes under documented conditions.
- Low-strength serviceability: The cured adhesive provides low-strength retention for adjustment, tamperproofing, or later disassembly.
Applications / Suitable for
- Low-strength locking of metal and plastic fasteners
- Tamperproofing screw heads and potentiometers
- Preassembled or post-applied retaining applications
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Chemistry Type
Ethyl cyanoacrylate / Aliphatic ester
Color
Dark blue liquid
The color
Component System
One component
Describes the number of components that must be supplied, mixed, or activated before application or cure.
Specific Gravity
1.1
Specific gravity (SG) is the ratio of the density of a substance to the density of a reference substance; equivalently, it is the ratio of the mass of a substance to the mass of a reference substance for the same given volume.
For liquids, the reference substance is almost always water (1), while for gases, it is air (1.18) at room temperature. Specific gravity is unitless.
Thermal Properties
Glass Transition Temperature (Tg)
165 °C
The glass transition temperature for organic adhesives is a temperature region where the polymers change from glassy and brittle to soft and rubbery. Increasing the temperature further continues the softening process as the viscosity drops too. Temperatures between the glass transition temperature and below the decomposition point of the adhesive are the best region for bonding.
The glass-transition temperature Tg of a material characterizes the range of temperatures over which this glass transition occurs.
Linear thermal expansion
100×10^-6 K -1
Thermal Conductivity
0.1 W/m.K
Thermal conductivity describes the ability of a material to conduct heat. It is required by power packages in order to dissipate heat and maintain stable electrical performance.
Thermal conductivity units are [W/(m K)] in the SI system and [Btu/(hr ft °F)] in the Imperial system.
Physical Properties
Viscosity
40 to 80 mPa.s
Viscosity is a measurement of a fluid’s resistance to flow.
Viscosity is commonly measured in centiPoise (cP). One cP is defined as
the viscosity of water and all other viscosities are derived from this base. MPa is another common unit with a 1:1 conversion to cP.
A product like honey would have a much higher viscosity -around 10,000 cPs-
compared to water. As a result, honey would flow much slower out of a tipped glass than
water would.
The viscosity of a material can be decreased with an increase in temperature in
order to better suit an application
Electrical Properties
Dielectric Strength
19.7 kV/mm
Dielectric strength is measured in kV per mm and is calculated by the Breakdown voltage divided by the thickness of the tested material.
Those two properties go hand in hand and while Breakdown voltage is always thickness dependent, dielectric strength is a general material property.
As an example, the dielectric strength of Polyimide is 236 kV/mm. If we place 1mm of Polyimide between two electrodes, it will act as an insulator until the voltage between the electrodes reaches 236 kV. At this point it will start acting as a good conductor, causing sparks, potential punctures and current flow.
Surface Resistivity
>1×10^15 Ohms Ohms/sq
Volume Resistivity
>1×10^15 Ohms⋅cm
Volume resistivity, also called volume resistance, bulk resistance or bulk resistivity is a thickness dependent measurement of the resistivity of a material perpendicular to the plane of the surface.
Additional Information
Technical properties
As-supplied / before-processing properties
Typical values for the product before cure, application, or assembly.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Appearance | Dark blue liquid | - | As supplied |
| Chemical type | Ethyl cyanoacrylate / aliphatic ester | - | As supplied |
| Components | One part | - | No mixing required |
| Specific gravity | 1.1 | - | 25 deg C |
| Viscosity | 40 to 80 | mPa s | Brookfield LVF, spindle 1, 30 rpm, 25 deg C |
| Cure mechanism | Humidity | - | Atmospheric moisture |
Technical properties
After-processing / final-state properties
Typical values for the cured or installed product under the listed conditions.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Fixture time | <2 | min | Plated metal and plastic fasteners |
| Full-strength development | 24 | h | Normal humidity-cure conditions |
| Operating temperature range | -54 to 85 | deg C | Typical application range |
| Dielectric breakdown strength | 19.7 | kV/mm | IEC 60243-1 |
| Volume resistivity | >1 x 10^15 | ohm cm | IEC 60093 |
| Torque strength, 4-40 fastener | 0.12 / 0.14 | N m | Breakaway / prevailing; zinc-plated, untorqued, cured 24 h at 22 deg C |
| Torque strength, 10-32 fastener | 0.36 / 0.23 | N m | Breakaway / prevailing; zinc-plated, untorqued, cured 24 h at 22 deg C |
