DuPont Pyralux LF7062R: 0.5 oz Cu / 1 mil PI — Low Profile Flex Laminate for Wearables and Medical Devices

When a flex PCB design sits at the intersection of “as thin as practical” and “stable enough to run through a proper fab process,” DuPont Pyralux LF7062R consistently earns its place on the material shortlist. It is not quite as extreme as the 0.5 mil Kapton builds in the LF7012R, but it brings the same ultra-light 0.5 oz copper weight together with a 1 mil Kapton core that handles panel registration, coverlay lamination, and routing far more predictably. For wearable electronics, skin-contact medical sensors, and compact consumer interconnects where both mass and total thickness are hard constraints — but you still need a material a real production fab can work with reliably — LF7062R fills that requirement in a way that few other standard constructions can.

This article covers DuPont Pyralux LF7062R from the ground up: what it is, how to read the part number correctly, its full layer construction, electrical and mechanical properties, practical design guidelines, and where it sits in the broader thin-flex material landscape. Grab a coffee — there’s a lot of ground to cover.

What Is DuPont Pyralux LF7062R?

DuPont Pyralux LF7062R is a single-sided, acrylic-adhesive-based flexible copper-clad laminate belonging to DuPont’s Pyralux LF product family. The construction consists of a 1 mil (25 µm) DuPont Kapton® polyimide dielectric film, bonded to a 0.5 oz/ft² (18 µm) rolled-annealed copper foil through a 0.5 mil (13 µm) C-staged modified acrylic adhesive.

The LF7062 features 1 mil Kapton, 0.5 mil adhesive, and 0.5 oz copper — a construction that delivers an extremely low total laminate profile while retaining dimensional stability meaningfully better than the 0.5 mil Kapton alternative. That stability advantage, relative to LF7012R, is precisely what makes LF7062R the construction that experienced flex fabricators actually prefer when building ultra-thin single-sided circuits at production scale.

Decoding the LF7062R Part Number

Understanding the Pyralux LF naming convention saves real time when you’re reviewing a BOM or comparing specs across a family of constructions. Here is how every digit in LF7062R maps to the physical build:

Code Position	Segment	Meaning
1–2	LF	Acrylic-based LF series, non-flame-retardant
3	7	LF7xxx sub-series: thin 0.5 mil (13 µm) acrylic adhesive
4	0	0.5 oz/ft² copper weight group
5	6	Construction index within sub-series
6	2	1 mil (25 µm) Kapton® polyimide dielectric
Suffix	R	Rolled-Annealed (RA) copper foil

The LF7 prefix is the key flag: any Pyralux part beginning with LF7 uses the 0.5 mil thin adhesive system, rather than the 1 mil adhesive in the LF9 family. That single adhesive difference knocks approximately 12 µm off the total stack versus the equivalent LF9 build — which matters more than it sounds when you are stacking flex layers inside a 3 mm device enclosure.

Full Layer Construction and Total Build Thickness

Layer	Material	Metric Thickness	Imperial Thickness
Copper Foil	Rolled-annealed (RA) copper	18 µm	0.5 oz/ft²
Acrylic Adhesive	C-staged modified acrylic	13 µm	0.5 mil
Dielectric Core	DuPont Kapton® polyimide	25 µm	1.0 mil
Total (uncovered)		~56 µm	~2.2 mil

At approximately 2.2 mil (56 µm) before coverlay, LF7062R slots neatly between the absolute minimum LF7012R (~1.7 mil) and the more common LF9110R (~3.4 mil). The additional 0.5 mil of Kapton over LF7012R adds dimensional stiffness without meaningfully compromising conformability — and for most wearable and medical applications, that tradeoff consistently proves the right call.

Electrical and Mechanical Properties of DuPont Pyralux LF7062R

All data below is from DuPont’s current Pyralux LF datasheet (EI-10117, 2020 revision), tested per IPC Test Method TM-650. These are typical values for the LF laminate family.

Property	Typical Value	Test Method
Dielectric Constant (Dk) @ 1 MHz	3.6	IPC-TM-650 2.5.5.3
Dielectric Constant (Dk) @ 10 GHz	3.0	ASTM D2520
Loss Tangent (Df) @ 1 MHz	0.02	IPC-TM-650 2.5.5.3
Loss Tangent (Df) @ 10 GHz	0.02	ASTM D2520
Peel Strength — After Lamination	1.8 N/mm (10 lb/in)	IPC-TM-650 2.4.9
Peel Strength — After Solder	1.6 N/mm (9 lb/in)	IPC-TM-650 2.4.9
Dimensional Stability (MD/TD)	±0.10%	IPC-TM-650 2.2.4
Solder Float, 288°C for 10 s	Pass	IPC-TM-650 2.4.13
Volume Resistivity	>10¹⁵ Ω·cm	IPC-TM-650 2.5.17
Surface Resistance	>10¹⁴ Ω	IPC-TM-650 2.5.17

The Df of 0.02 at both 1 MHz and 10 GHz is notably flat across frequency — more so than many acrylic-based systems — which makes LF7062R more useful for moderate-frequency signal applications like Bluetooth LE, ANT+, and 915 MHz ISM band circuits than its acrylic construction might initially suggest. It is not a purpose-built RF laminate, but for the BLE and sub-GHz radios that most wearables and medical patch devices rely on, the loss performance is adequate.

IPC Certification Status: What Engineers Need to Know

LF7062R is not certified to IPC-4204/1 in the current DuPont standard catalog. This is consistent across the LF7xxx ultra-thin sub-series where the combination of 0.5 mil adhesive and non-standard Kapton thickness places the construction outside the certified range. Engineers working on regulated medical device programs, aerospace contracts, or defense work that requires IPC-4204/1 traceability must be aware of this upfront. In those cases, the closest IPC-certified alternatives with similar mass profiles are LF7011R (1 oz / 0.5 mil adhesive / 1 mil Kapton — certified) or LF9110R (1 oz / 1 mil adhesive / 1 mil Kapton — certified). For commercial, industrial, and most consumer medical wearable applications where IPC certification is not a contract requirement, this poses no practical constraint.

LF7062R vs. Key Alternatives in the Thin-Flex Category

Choosing the right construction requires a clear-eyed comparison across the options that are realistically on the table for the same design problem. Here is where LF7062R fits:

Product Code	Cu Weight	Adhesive	Kapton	Sides	Total Stack	IPC-4204	Primary Advantage
LF7062R	0.5 oz / 18 µm	0.5 mil	1.0 mil	Single	~2.2 mil	No	Best fab-handleable ultra-thin build
LF7012R	0.5 oz / 18 µm	0.5 mil	0.5 mil	Single	~1.7 mil	No	Minimum possible thickness
LF7004R	0.5 oz / 18 µm	1.0 mil	0.5 mil	Single	~2.2 mil	No	Thicker adhesive, same total
LF7002R	1.0 oz / 35 µm	0.5 mil	0.5 mil	Single	~2.4 mil	No	1 oz current capacity, ultra-thin
LF7014R	0.5 oz / 18 µm	0.5 mil	1.0 mil	Double	~2.7 mil	No	Double-sided equivalent
LF9110R	1.0 oz / 35 µm	1.0 mil	1.0 mil	Single	~3.4 mil	Yes	Standard certified thin flex

The practical distinction between LF7062R and LF7012R deserves a direct callout because engineers choose between them regularly. Both share identical copper weight and adhesive thickness. LF7062R’s 1 mil Kapton versus LF7012R’s 0.5 mil Kapton adds only 0.5 mil (~12 µm) to the total stack. In exchange, you get a substrate that registers more accurately during imaging, resists wrinkling during panel handling, and gives the coverlay adhesive a more stable surface to bond against. For any design that will go through a real flex fabrication line — rather than a bench-top DIY process — LF7062R is the significantly more manufacturable of the two.

Design Guidelines for DuPont Pyralux LF7062R

Bend Radius Calculations for Wearable and Medical Applications

The combination of 0.5 oz copper and a total stack of approximately 56 µm gives LF7062R a compelling minimum bend radius for wearable form-factor designs. Using the IPC-2223 guideline of approximately 6× total laminate thickness for static-service RA copper flex, the practical static bend radius for LF7062R is around 0.34 mm. In practice, after accounting for coverlay addition (typically adding another 38–51 µm to the total stack), real-world static bend radius targets in the 0.5–1 mm range are routinely achieved.

For dynamic flex service — circuits expected to bend tens of thousands to millions of times in service, as in a wrist-worn heart rate monitor or a continuous glucose monitor patch — the industry guideline moves to a 20× to 40× multiplier on total laminate thickness. At 40× for LF7062R’s ~56 µm base stack, dynamic minimum is approximately 2.2 mm. The rolled-annealed copper’s grain structure is fundamental to this capability: RA copper flexes without cracking at radii that would fracture electro-deposited copper of the same thickness. Never specify the ED variant for high-cycle dynamic service.

Trace Width, Spacing, and Fine-Line Capability on 0.5 oz Copper

The 18 µm copper weight in LF7062R is the construction’s strongest argument for fine-pitch signal routing. Etching 0.5 oz copper produces crisper line edges than heavier foil because the reduced undercut at fine pitch is proportionally less significant. Standard production minimum trace width on 0.5 oz copper is 3 mil (75 µm) trace and space, with specialist fine-line fabs holding 2 mil (50 µm) under tightly controlled processes.

The tradeoff is current capacity. A 0.5 oz copper trace carries roughly half the current of a 1 oz trace at the same width for the same temperature rise. For a wearable BLE sensor node with a 3.7V LiPo cell, a 10 mil trace on 0.5 oz copper handles approximately 500–600 mA safely — sufficient for a small BLE SoC and its associated passives, but not adequate for a high-power wireless charging receiver or a DC motor driver. If your design has significant mixed-current requirements, evaluate whether 0.5 oz copper handles every net before committing to LF7062R.

Impedance Control with 1 mil Kapton at 0.5 oz Copper

The 1 mil (25 µm) Kapton in LF7062R represents a meaningful step up from the 0.5 mil core of LF7012R for controlled impedance work. The dielectric height H is doubled at 25 µm versus 13 µm, which gives your impedance calculator more room to work with and results in wider trace widths for a given impedance target — making the design less sensitive to copper thickness variation and etch tolerance.

For a 50Ω microstrip target on LF7062R using Dk = 3.6, a 0.5 oz (18 µm) copper trace over a 1 mil Kapton dielectric requires a trace width of approximately 25–30 µm depending on coverlay geometry — extremely fine by production standards, but physically achievable with the right fab partner. For most BLE and sub-GHz RF traces in wearable designs, a 50Ω stripline-matched feed line of this width is well within laser-defined or photolithographic capability. Always validate against measured coupon data before production release; acrylic adhesive systems can show Dk variation between different lot conditions.

Coverlay and Surface Finish Recommendations for Medical Wearables

The standard LF-series acrylic coverlay — Kapton film with B-staged acrylic adhesive — is the default pairing for LF7062R. For wearable and medical applications, the coverlay adhesive thickness deserves specific thought. At 0.5 oz copper (18 µm post-etch trace height), a 0.5 mil (13 µm) coverlay adhesive is adequate for most trace pitches, but a 1 mil (25 µm) coverlay adhesive provides better void-free encapsulation for trace geometries below 5 mil pitch.

For skin-contact applications, verify the biocompatibility of both the base laminate and the coverlay with your regulatory affairs team. DuPont’s standard caution note applies: Pyralux materials are not intended for use in medical applications involving permanent implantation. External skin-contact applications are a different regulatory category, but documentation of the material’s composition and any relevant cytotoxicity or irritation test data will be needed for FDA Class II device submissions. Request the DuPont Medical Caution Statement (H-50102) from your distributor for inclusion in your design history file.

Regarding surface finish, ENIG (Electroless Nickel Immersion Gold) is the most common choice for fine-pitch LF7062R designs, particularly when the flex circuit lands on spring contacts or membrane connectors in wearable assemblies. Organic Solderability Preservative (OSP) is acceptable for cost-sensitive consumer applications where shelf life is manageable.

Processing Parameters for DuPont Pyralux LF7062R

Parameter	Specification
Lamination Temperature	182–199°C (360–390°F)
Lamination Pressure	14–28 kg/cm² (200–400 psi)
Time at Temperature	1–2 hours
Storage Temperature	4–29°C (40–85°F)
Maximum Humidity	Below 70% RH
Standard Sheet Formats	24×36 in / 24×18 in / 12×18 in
Pack Size	4 sheets minimum, 25 sheets maximum
Warranty Period	2 years from date of shipment
Quality Management	ISO 9001:2015 certified facility

Typical Applications Where DuPont Pyralux LF7062R Excels

Wearable biometric sensors — Heart rate bands, SpO₂ monitoring patches, continuous glucose monitors, and electrodermal activity wristbands all benefit from LF7062R’s thin, conformal profile. The 0.5 oz copper handles the micropower signal traces from sensor front-ends and BLE SoCs, while the 1 mil Kapton provides enough substrate stiffness to maintain registration through SMT assembly.

Disposable and semi-disposable medical patches — Adhesive ECG patch electrodes, pain management patches with embedded stimulation circuitry, and single-use biosensors represent one of the fastest-growing applications for thin flex laminates. LF7062R’s 2.2 mil total stack keeps the patch profile low enough to avoid creating pressure discomfort under a tight-fitting electrode adhesive.

Hearing instruments — Custom in-the-ear and receiver-in-canal hearing aids need flex interconnects that fit inside curved acrylic shells with interior channels as small as 2–3 mm diameter. LF7062R’s profile gives enough clearance for the circuit plus any conformal coating while leaving room for the acoustic path.

Consumer electronics antenna flex cables — NFC coil interconnects, GPS antenna feeds, and Bluetooth trace antennas in compact wearables benefit from LF7062R’s low dielectric constant (3.6 at 1 MHz, 3.0 at 10 GHz) and thin substrate that keeps the antenna element close to the device surface without adding mechanical bulk.

Miniaturized robotics sensor loops — Flexible sensor arrays for prosthetic limbs, soft robotics actuators, and minimally invasive surgical tools that flex repeatedly in service are appropriate candidates for LF7062R’s RA copper and thin-Kapton combination.

Useful Resources for Engineers Working with DuPont Pyralux LF7062R

Resource	Access
Pyralux LF Datasheet (EI-10117, current)	pyralux.dupont.com
Pyralux LF Technical / Processing Manual	Request from DuPont or Qnity sales rep
Pyralux LF Safe Handling Guide	pyralux.dupont.com
DuPont Medical Caution Statement H-50102	Via DuPont distributor / sales rep
IPC-2223: Sectional Design Standard for Flex PCBs	ipc.org
IPC-TM-650 Test Methods	ipc.org
IPC-4204/1 Flexible Metal-Clad Dielectrics Spec	ipc.org
Pyralux Laminate Product Selector Tool	pyralux.dupont.com
Insulectro Pyralux LF Product Page	insulectro.com/products/pyralux-lf
DuPont PCB Materials Reference Guide	PCBsync DuPont PCB Overview

5 Frequently Asked Questions About DuPont Pyralux LF7062R

Q1: What is the practical difference between LF7062R and LF7012R for a wearable design?

Both constructions use identical copper weight (0.5 oz / 18 µm) and adhesive thickness (0.5 mil / 13 µm). The only structural difference is Kapton thickness — 1 mil (25 µm) in LF7062R versus 0.5 mil (13 µm) in LF7012R. In practice, LF7062R handles significantly better on the fab floor: the thicker Kapton resists panel wrinkling during imaging, holds artwork registration more accurately, and provides a more stable surface for coverlay lamination. The total thickness penalty is approximately 0.5 mil (~12 µm). For a design heading to production, LF7062R is almost always the more reliable choice. LF7012R makes sense when that extra 12 µm is genuinely a hard constraint — which is rare outside extreme miniaturization work.

Q2: Is DuPont Pyralux LF7062R IPC-4204/1 certified?

No. LF7062R falls outside the IPC-4204/1 certified range in DuPont’s current standard catalog. This applies to the broader LF7xxx ultra-thin sub-series. If your medical device or aerospace program requires IPC-4204/1 documentation in the design history file, the nearest certified alternatives are LF7011R (1 oz / 0.5 mil adhesive / 1 mil Kapton) or LF9110R (1 oz / 1 mil adhesive / 1 mil Kapton). Both are IPC-certified and slightly heavier in copper weight. For commercial wearables and consumer medical devices where IPC certification is not a contractual requirement, the absence of certification on LF7062R is not a practical obstacle.

Q3: Can I use LF7062R for dynamic flex in a fitness wristband application?

Yes — the RA copper suffix “R” is the key indicator that this construction is suitable for dynamic flex. Rolled-annealed copper’s elongated grain structure resists fatigue cracking under repeated bending significantly better than electro-deposited copper of the same weight. For fitness wristband applications with moderate bending cycles (tens of thousands of cycles over a multi-year product life), LF7062R with a properly designed bend zone — traces running parallel to the bend axis, no vias in the flex zone, appropriate minimum bend radius per IPC-2223 — is well suited to the application. For higher-cycle applications approaching millions of cycles, validate with accelerated flex fatigue test coupons before finalizing the design.

Q4: What surface finish works best with LF7062R for skin-contact medical patches?

ENIG (Electroless Nickel Immersion Gold) is the most widely used finish on LF7062R for medical wearable applications. It provides a flat, solderable, and biocompatible-compatible surface that plays well with the fine-pitch SMT components typical of sensor front-end designs. For purely capacitive electrode contacts that do not require soldering — such as dry ECG or EEG electrodes — a gold flash or specialized conductive film coating may be preferable. Avoid HASL (Hot Air Solder Level) finishes on 0.5 oz copper builds: the thermal shock and surface planarity issues with HASL interact poorly with thin copper and can cause delamination at the adhesive interface under extreme process conditions.

Q5: How does LF7062R compare to the LF7014R double-sided version?

LF7014R is the double-sided counterpart to LF7062R, sharing the same 0.5 oz copper / 0.5 mil adhesive / 1 mil Kapton construction on both sides of the dielectric. The total uncovered stack for LF7014R is approximately 2.7 mil (~69 µm), adding only about 0.5 mil over LF7062R due to the second copper and adhesive layer. LF7014R is not IPC-4204/1 certified either. Choose LF7014R when your wearable or medical design requires routing on both sides of the flex layer — typically for designs where signal density exceeds what a single-sided construction can handle, or where a ground return plane on the back of the substrate improves EMC performance for the radio or sensor analog front end.

Engineer’s Final Assessment

DuPont Pyralux LF7062R is the construction that hits the right balance for the largest category of thin-flex wearable and medical circuit designs: ultra-low copper weight for fine-pitch signal routing and minimum mass, paired with a 1 mil Kapton substrate that a production fabricator can process reliably without the panel-handling headaches of a 0.5 mil dielectric. It is not the absolute thinnest option DuPont offers, and it does not carry IPC-4204/1 certification — so it is not the right call for every project. But for a commercial fitness tracker, a consumer medical patch, a hearing instrument interconnect, or a wearable sensor node headed into volume production, LF7062R has the property profile and the fab-floor processability to make it the practical engineer’s first choice in the ultra-thin LF category.

Pair it with a flex-experienced fabricator, follow IPC-2223 design rules for your bend zone geometry, and validate coverlay selection against your specific trace pitch — and this material will perform exactly as the numbers suggest.