Liquid Encapsulants

Encapsulants for electrical insulation and mechanical protection

Liquid Encapsulants

Liquid encapsulants are much more flexible than traditional Epoxy mold compounds, removing the need for expensive molding machines and molding plates. This way, they allow manufacturers to produce smaller and and more flexible batches, making the products better suited for diverse low quantity orders. Optical grade encapsulants can also have efficient application in LED encapsulation.

Encapsulants are primarily used to ensure environmental protection and boost the mechanical strength of wire bonded devices. They are developed to provide protection to wire bonds, leads and aluminum.

Encapsulants deliver unmatched performance for a variety of products including transistors, system in package (SIP) devices, ASICs, and chip-on-board applications. Cycle time and costs can be reduced through the use of glob tops. These materials for chip-on- board applications are designed to cure quickly to fit easily within high-speed manufacturing operations.

Liquid encapsulants are formulated and tested in-process and in the context of full package assembly. They meet the most stringent JEDEC-level testing requirements and are developed to deliver outstanding performance within high temperature lead-free environments. Krayden offers a wide range of Liquid Encapsulants. We are proud to offer Henkel\'s entire LOCTITE product line but also our own LinqSil and Optolinq products.

Product selector guide

The table below gives a quick overview of our current leading products for liquid encapsulation. Please scroll below for the entire encapsulation range.

Leading Encapsulant Adhesives
	FIL7010C	FP 4470	FP 4450HF	FP4802	FP 4651	FP 4653	FP 4451TD	DAM 7010C
Color	Black	Black	Black	Black	Black	Black	Black	Black
Viscosity	25,000	42,000	32,000	80,000	>100,000	>100,000	300,000	92,500
Silica Filler %	80	75	73	72	82	86	73	80
Max filler size, um	120	50	25	50	50	75	200	120
SVHC	FREE	YES	YES	FREE	YES	YES	YES	FREE
Ionics level, ppm	<10	<2	<2	<5	<5	<10	<10	<10
Tg by TMA, °C	135 - 145	148	164	50	150	150	150	135 - 145
CTE1	16	18	21	20	11	7	21	16
CTE2	58	65	72	100	50	NA	65	63
Cure time, min(2 steps)	60 + 60	30 + 90	30 + 90	30 + 90	60 + 90	150 + 150	30 + 90	60 + 60
Cure temperature °C	100 + 150	125 + 165	125 + 165	125 + 165	125 + 165	110 + 150	125 + 165	100 + 150
Pot life at 25°C	1	3	4	0.33	2	1	10	1
Shelf life at -40°c, months	6	9	9	9	9	9	9	6
Encapsulant Type	FILL					DAM

Encapsulant Adhesives
Product	Apps and Attributes	Viscosity at 25°C (mPa.s)	Filler Type (Content)	Max Filler Size, um	Hardener type	Tg by TMA (°C)	CTE α1(ppm/°C)	CTE α2(ppm/°C)	Cure time (min)	Cure Temp °C
Dam
LINQBOND LB-DM801	Designed to work in conjunction with LB-FL501 as a dam material for semiconductor packaging.	42,000	-	-	-	139	20	60	40+20	150 + 160
Loctite ECCOBOND 7010C DAM	Protection of bare IC, Well defined height	92,500	Silica (80%)	120	SVHC free	140	16	63	60 - 60	100 + 150
Loctite ECCOBOND EO 7029	Smartcard encapsulation and die attach	48,000	-	-	-	110	66	181	5	150
Loctite ECCOBOND FP4451TD	BGA and memory encapsulation. Highest aspect ratio for Tall Dam	300,000	Silica (73%)	200	Anhydride	150	21	65	30 + 90	125+165
Loctite ECCOBOND FP4451	Discontinued - No longer available	300,000	Silica (72%)	-	Anhydride	155	22	-	30 + 90	125+165
Fill
LINQBOND LB-FL501	One-component fill epoxy encapsulant specifically designed for rapid temperature fluctuations	37,000	-	-	-	180	23	77	30 + 90	135 + 175
Loctite ECCOBOND 7010C FIL	Potting or encapsulation protection for stress sensitive components	25,000	Silica (80%)	120	SVHC free	140	16	58	60 + 60	100 + 150
Loctite ECCOBOND FP0087	Stress-sensitive devices and severe automotive environments	20,000 at 20 rpm	Silica (76%)	N/A	Anhydride	175	18	69	60 + 60	125 + 180
Loctite ECCOBOND FP4450	Discontinued - No longer available	44,000	Silica (73%)	120	Anhydride	155	22	72	30 + 90	125+165
Loctite ECCOBOND FP4450HF	Automotive, BGA, memory, COB, SIP and SmartCard	32,000 at 20 rpm	Silica (73%)	25	Anhydride	164	19	71	30 + 90	125+165
Loctite ECCOBOND FP4470	BGA, CSP, and full array on low temperature co-fired ceramic (LTCC)	48,000	Silica (75%)	50	Anhydride	148	18	65	30 + 90	125+165
Loctite ECCOBOND FP4650	High purity and low thermal expansion	325,000	Silica (83%)	-	-	140	15	-	60 + 120	120 + 160
Loctite ECCOBOND FP4651	Automotive, BGA, memory, COB, SIP, SmartCard and chip array ceramic packages	130,000 at 20 rpm	Silica (82%)	50	Anhydride	150	12	50	60 + 90	125+165
Locite ECCOBOND FP4653	Chocolate breakable on pre-scored ceramic substrate	85,000	Silica (86%)	-	-	150	7	-	120 + 120	110 + 150
Loctite ECCOBOND FP4654	Discontinued - No longer available	32,000 at 20 rpm	Silica (80%)	50	Anhydride	146	13	53	30 + 90	125+165
Loctite ECCOBOND FP4802	BGA, CSP and full array on low temperature co-fired ceramic (LTCC)	80,000 at 10 rpm	Silica (72%)	50	Phenolic	50	20	100	30 + 90	125+165
Loctite STYCAST A316-48	Automotive grade potting material with High Tg for sensors and control modules	50,000	Oxide	-	Amine	145	55	155	30 + 120	100
Glob Top
LINQBOND GT2301	Provides excellent protection against moisture and vibration	65,000	-	-	-	130	50	160	40	120
Loctite ABLESTIK ME 995-1-4	Thermally conductive glob top	205,000	Silica	-	-	110	45	-	60	150
Loctite ECCOBOND EN 3838T	Low temperature cure PCB protection	6,700	-	-	-	2	57	217	8	130
Loctite ECCOBOND EN 3915T	Low CTE for flip chip device aplications	22,000	-	-	-	130	24	103	7	160
Loctite ECCOBOND EO 1016	Encapsulation of smart cards and watch ICs	62,000	Alumina	N/A	Amine	126	46	140	20	150
Loctite ECCOBOND FP4323	COB and plastic PGA encapsulation	220,000 at 2 rpm	Silica (65%)	-	-	174	28	-	240 or 60	150 or 170
Loctite ECCOBOND FP4460	Automotive, BGA, memory, COB, SIP and SmartCard	300,000 at 10 rpm	Silica (75%)	120	Anhydride	173	20	70	180	150
Loctite ABLESTIK 8387BM	Discontinued - No longer available	14,000	PTFE, Silica	10	Hybrid Epoxy	122	88	168	5 or 60	150 or 100
Loctite ECCOBOND 50300HT	Wire bonded bare die encapsulation	130,000	Silica (68%)	150	Anhydride	140	20	-	60 + 60	120 + 150
Loctite ECCOBOND 50300-1	Wire bonded bare die encapsulation	100	Silica(70%)	-	-	140	20	-	120	150
Loctite ECCOBOND 50300LT	Wire bonded bare die encapsulation	55	Silica (69%)	-	-	140	20	-	120	150
Loctite ECCOBOND 50400-1	Wire bonded bare die on epoxy laminates	40,000 at 20 rpm	Silica(70%)	150	Amine	140	20	-	60 + 60	120 + 150
Loctite ECCOBOND FP4660	CSP and low stress applications	120,000 at 5 rpm	Silica (80%)	120	Anhydride	135	13	56	30 + 90	125+165
Loctite ECCOBOND UV8800M	Discontinued - No longer available	2,500 - 4,000 at 5 rpm	Silica (54%)	21	-	29	41	135	2 seconds	315 - 400 nm (UV)
Loctite ECCOBOND UV8800M-X	Discontinued - No longer available	3,400	-	-	-	47	48	149	30 sec	100 mW/cm2
Loctite ECCOBOND UV 9052	UV cure for inkjet applications	41,000	-	-	-	-	-	-	5 - 10 sec	0.5 - 1 J
Loctite ECCOBOND UV 9060F	Protection of WLCSP and BGA	11,000	-	-	-	75	81	198	5 - 25 sec	300 w/In
Loctite EO7021	CSP, BGA and SmartCard encapsulation	17,000 at 5 rpm	-	-	-	125	67	187	60 or 5	120 or 150
Loctite SI 5088	UV and moisture cure for gasketing and sealing on glass, metals and ceramics	65,000	Unfilled	-	Silicone	-	3	-	Mix	Mix
Loctite SI 5293	UV cure silicone for PCB protection	-	-	-	Silicone	-40	300	-	-	-
Loctite STYCAST 2851FT	Solvent free encapsulant	85,000	-	-	-	-	31	-	60	120
Loctite STYCAST SC3613	LED display coating and IC hybrid passivation	3,500	Unfilled	-	Silicone	-	-	-	30 + 60	120 + 150
Loctite STYCAST U2500	For transformer PCBs and insulation apps	6,000	Polyurethane	-	-	-53	155	-	240	60

Frequently asked questions

Frequently Asked Questions about Liquid Encapsulants

How do I choose the correct needle for dispensing filled materials, and what should I expect during curing?

For filled materials, select a nozzle ID ≥ 3× the maximum particle size of the encapsulant. Example, for FP4451TD (median ~20 µm, max ~200 µm): 20G (0.60 mm), 18G (0.84 mm), or 16G (1.19 mm). Always validate your chosen needle over a production run for dispensing consistency.

Do you have UV cured silicones with high refractive index?

We don't have high refractive index materials that cure with UV. The UV activators required limit transmission, and UV exposure can damage the silicone, causing yellowing and further reducing transmission. UV-cured silicones are generally not suitable for high-transmission, high-refractive applications.

What causes bubbles in my encapsulant?

Most bubbles are not caused by the encapsulant itself. For solvent-based materials, outgassing can occur, but in 100% solid systems like FP4450 and FP4451TD, outgassing is negligible. Bubbles usually originate from moisture in the substrate. Prebaking the substrate or storing it in a dry box prevents bubble formation.

What is substrate prebaking?

Prebaking removes moisture from substrates previously exposed to humidity. Typical prebaking: 100°C for 1 hour. After prebaking, follow the recommended dispense and cure steps in the TDS. Alternatively, store substrates in a dry box or use a lower temperature step-cure if prebaking is not feasible.

How do I know when my product is fully cured?

Materials are fully cured after following the recommended cure schedules in the TDS. Differential Scanning Calorimetry (DSC) cure kinetics can be used to confirm complete curing.

How many volts can liquid encapsulants typically withstand?

Typical silica-filled encapsulants withstand 500–1000 V/mil (20–40 kV/mm). For higher voltages, verify the electrode gap, not just encapsulant thickness, to ensure proper insulation.

What are PCB/Component protection encapsulants?

PCB protection encapsulants shield passive components (capacitors, resistors) from dust, moisture, and mechanical impact. Examples include LOCTITE ECCOBOND 3838T (black low-modulus epoxy), UV9060F (light blue UV acrylate with moisture cure), ABP 6892 (clear epoxy), clear silicones 8035 and STYCAST SC 3613, and LOCTITE 3217 (UV/heat dual-cure).

For better encapsulant retention, a DAM may be needed. Recommended options include black ABP 8420 epoxy, black ABP 8142B silicone, or thixotropic LOCTITE 3621 red epoxy and LOCTITE 3217, which can be UV cured before the fill operation.

Learn more

Liquid Encapsulants

Epoxy Mold Compound vs Liquid Encapsulation

There are two main ways to encapsulate a semiconductor device: transfer molding a thermosetting Epoxy Mold Compound (EMC) or using liquid encapsulation directly on the Printed Circuit Board (PCB). Encapsulation in EMC is better than liquid encapsulation for applications that require higher filler content, and for the same reason, volume for volume, EMC is usually cheaper than liquid.

Liquid encapsulation, on the other hand, has a high flexibility and low throughput

Liquid casting is however much more flexible. EMC requires are large significant investment in molding machines and mold plates for specific devices which must produce large quantities before there is a return on that investment. Liquid encapsulation on the other hand has a high flexibility and low through put: meaning that it is best suited for a multiple diverse low quantity orders.

Liquid resins are used in two main ways in encapsulations processes: glob top and dam & fill alternatively known as frame & fill

Liquid resin encapsulation via the glob top process is a single step application process but is less precise than dam & fill

In general liquid encapsulation is used for LEDs and potting or encapsulating electronics in bare die mounting on printed circuit boards (PCB), otherwise known as chip on board (COB).

Another advantage of potting and encapsulating devices in liquids is that in general, the result is flatter and thinner than devices encapsulated by a transfer molding process around a lead-frame with EMC. The space requirements for devices will continue getting more and more stringent as the component density of devices increases. This trend makes encapsulation and potting in liquids a sure bet for the future.

Transfer molding EMC may also cause wire sweep: where the pressure of the flowing molten compound shifts the fine-pitched bonding wires connecting a die. Wire sweep can cause shorts and mutual inductance. Liquid encapsulation is applied from above and does not disturb bonding wires. That’s why it is the industry standard for larger or extra sensitive dies and chips.

Liquid Epoxy: Viscosity and Thixotropy

Bare die may be mounted to the PCB with die attach but that’s not enough to protect them or their connecting wires from moisture, mechanical stress, temperature, and chemical corrosion. That’s why it makes sense to insulate and encapsulate them with a protective potting layer of liquid encapsulant.

The low viscosity of liquid encapsulants is good for flat smooth finishes.

In non-Newtonian thixotropic encapsulants thixotropy refers to the temporarily lower viscosity of an epoxy gel when shear, pressure, or temperature is applied. This means that they can be gel-like when at rest, but flow like a liquid when agitated.

Being able to control the viscosity of liquid encapsulants means you can dial in how far they will spread over a surface area, and also how high they will build up to. This is important in Glob Top encapsulation where devices are literally encapsulated by a “Glob” from above.

Dam & Fill or Frame & Fill is a two step encapsulation process that is a little like 3D printing

Glob Top vs Dam & Fill

GlobTopVSDamFill

Glob Top is a process of encapsulation by using a fluid encapsulant gel with higher viscosity so that it fully encapsulates a device without flowing beyond the necessary area. As mentioned, by controlling the temperature, shear, and pressure, the viscosity and flow of liquid can be adjusted so that the final surface area and height of the “Glob” can be controlled quite effectively.

Dam & Fill on the other hand refers to a two-step process of encapsulation, where a ring or frame of higher viscosity liquid encapsulant is applied as a “Dam” around a device, and then a lower viscosity liquid “fill” is used to then fully encapsulate a device. The liquid used to build the frame or dam usually has more abrasive filler and a higher viscosity at rest than the liquid used for the fill.

Dam & Fill is a more selective protective coating and can be framed to cover areas in specific shapes, and is for example also used for optical bonding. In optical bonding the frame or dam is used to create a space between the glass and the display or touch screen. Then an optically clear fill is used as an adhesive and fixative.

Liquid Encapsulation for LEDs and Optoelectronic Devices

Optically clear liquid encapsulation is also used for LED devices, and encapsulate optical or optoelectronic devices that require both a high level of light transmittance as well as a good level of mechanical protection. In a similar process to Glob Top encapsulation, a literal glob of clear encapsulant is dropped directly into place on top of the LED. In another production process, optically clear liquid encapsulant is used to cast LED’s final body. Phosphor, colored dyes, and diffusant concentrates can be added to the liquid encapsulant to alter its optical properties.

Presentations

2026 Encapsulants

This presentation introduces encapsulant materials used to protect electronic components and assemblies from moisture, contaminants, vibration, and mechanical stress. It covers encapsulant chemistries, key performance characteristics, application methods, and material selection considerations for enhancing the reliability and long-term durability of electronic devices across industrial, automotive, and consumer applications.

2026 Materials for Optoelectronic Applications

This presentation provides an overview of advanced materials used in optoelectronic applications, including adhesives, encapsulants, thermal interface materials, and optical bonding solutions. It explores material requirements for LEDs, displays, optical sensors, and photonic devices, with a focus on optical clarity, thermal management, environmental protection, and long-term performance in demanding operating environments.

Related Blogs

Encapsulants – Guardians of Integrated Circuits

George Kountardas, July 2025

This blog provides a comprehensive introduction to encapsulants, their applications, and why they are considered the guardian angels of integrated circuit assemblies.

Yellowing in Epoxy-Based Liquid Encapsulants

James Baduria, February 2025

This blog talks about the mechanism behind the yellowing in epoxy-based liquid encapsulants and the strategies that can be adapted so as to prevent or minimize it.

Better Thermal Conductivity in Encapsulants

Rose Anne Acedera, January 2025

A summary of the recent research effort carried out where the interdependence of thermal conductivity with crucial properties of polymer-based encapsulants was investigated

Liquid Encapsulants

Product selector guide

Frequently asked questions

Frequently Asked Questions about Liquid Encapsulants

Learn more

Liquid Encapsulants

Epoxy Mold Compound vs Liquid Encapsulation

Liquid encapsulation, on the other hand, has a high flexibility and low throughput

In general liquid encapsulation is used for LEDs and potting or encapsulating electronics in bare die mounting on printed circuit boards (PCB), otherwise known as chip on board (COB).

Liquid Epoxy: Viscosity and Thixotropy

The low viscosity of liquid encapsulants is good for flat smooth finishes.

Glob Top vs Dam & Fill

Liquid Encapsulation for LEDs and Optoelectronic Devices

Presentations

2026 Encapsulants

2026 Materials for Optoelectronic Applications

Related Blogs

Encapsulants – Guardians of Integrated Circuits

Yellowing in Epoxy-Based Liquid Encapsulants

Better Thermal Conductivity in Encapsulants

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