Arlon DiClad 870: PTFE Woven Glass Laminate with Dk 2.33 – Complete Review

There’s a specific gap in the PTFE laminate landscape that Arlon DiClad 870 fills better than almost anything else: the sweet spot between high mechanical stability and genuinely low loss. Most PTFE-based PCB materials force you to choose — either you take the highly reinforced version and accept a higher Dk and slightly elevated dissipation factor, or you go with the lightly reinforced version, get a lower Dk and Df, but inherit a softer, harder-to-handle material that causes headaches in fabrication. DiClad 870 doesn’t make you pick one extreme. It uses a medium fiberglass-to-PTFE ratio that delivers a Dk of exactly 2.33 — lower than the DiClad 522/527 series but with better mechanical properties than DiClad 880 — and a dissipation factor of 0.0013 at 10 GHz that puts it firmly in the top tier of low-loss substrates. This guide is a complete engineering review of the material: every spec worth knowing, the thickness and copper options available, where it fits in the application landscape, how it compares to the competition, and what you need to know before you take it to your fabricator.

What Is Arlon DiClad 870?

Arlon DiClad 870 is a woven fiberglass-reinforced PTFE composite laminate designed for use as a printed circuit board substrate in microwave and RF applications. It belongs to the DiClad product family — a line of PTFE-based PCB materials developed by Arlon and now manufactured under the Rogers/Arlon EMD umbrella, following Elite Material Co.’s acquisition of Arlon EMD in January 2021. Production continues at the Rancho Cucamonga, California facility, and the DiClad 870 specification is unchanged.

The defining design choice in DiClad 870 is its deliberate positioning in the fiberglass/PTFE ratio spectrum. Using fewer plies of woven fiberglass and a higher ratio of PTFE content than the DiClad 522/527 series, DiClad 870 achieves a lower dielectric constant and improved dissipation factor without sacrificing the mechanical stability that makes woven-glass PTFE laminates practical to fabricate. In practical terms: you get meaningfully better RF performance than DiClad 522/527, you retain better mechanical properties than DiClad 880, and you don’t have to run PTFE-specific fabrication processes that are any more demanding than what the 522/527 series already requires.

Understanding where DiClad 870 sits in the DiClad family is key to knowing when to specify it. The entire DiClad series is built on controlled fiberglass/PTFE ratio management, with the product lineup spanning from maximum reinforcement (DiClad 522/527, Dk 2.40–2.65) through the medium-reinforced DiClad 870 (Dk 2.33) down to the lightly reinforced DiClad 880 (Dk 2.17–2.20). If you’ve been using DiClad 522 for everything and wondering whether there’s a way to get lower loss without completely changing your fabrication process, DiClad 870 is the answer worth evaluating first.

Arlon DiClad 870 Full Electrical Specifications

The electrical specs below come from the official Arlon/RS-online published datasheet. All values are based on 0.062″ dielectric thickness, exclusive of metal cladding, tested per the IPC and ASTM methods noted.

Parameter	Test Method	Condition	DiClad 870
Dielectric Constant (Dk) @ 10 GHz	IPC TM-650 2.5.5.5	C23/50	2.33
Dielectric Constant (Dk) @ 1 MHz	IPC TM-650 2.5.5.3	C23/50	2.33
Dissipation Factor (Df) @ 10 GHz	IPC TM-650 2.5.5.5	C23/50	0.0013
Dissipation Factor (Df) @ 1 MHz	IPC TM-650 2.5.5.3	C23/50	0.0009
Thermal Coefficient of Er (ppm/°C)	IPC TM-650 2.5.5.5 Adapted	–10°C to +140°C	–161
Volume Resistivity (MΩ-cm)	IPC TM-650 2.5.17.1	C96/35/90	1.5 × 10⁹
Surface Resistivity (MΩ)	IPC TM-650 2.5.17.1	C96/35/90	3.4 × 10⁷
Arc Resistance (seconds)	ASTM D-495	D48/50	> 180
Dielectric Breakdown (kV)	ASTM D-149	D48/50	> 45
Water Absorption (%)	MIL-S-13949H / IPC TM-650 2.6.2.2	E1/105 + D24/23	0.02
Flammability	UL File E 80166	UL94 Vertical Burn	UL94V-0

Two numbers here deserve particular attention. First, the Dk of 2.33 is completely stable between 1 MHz and 10 GHz — it doesn’t drift with frequency. For wideband or multi-band designs, this frequency-flat dielectric constant means your transmission line models hold up across the entire operating band without needing frequency-dependent corrections. Second, the Df of 0.0013 at 10 GHz is a legitimate step down from the 0.0018–0.0022 range you see in the DiClad 522/527 series. At 10 GHz, that difference in Df translates into meaningfully lower insertion loss in feed networks, coupled structures, and antenna elements — especially when trace runs are long or the signal budget is tight.

Arlon DiClad 870 Full Mechanical and Physical Properties

Parameter	Test Method	Condition	DiClad 870
CTE — X Axis (ppm/°C)	IPC TM-650 2.4.24 / Mettler TMA	0°C to 100°C	17
CTE — Y Axis (ppm/°C)	IPC TM-650 2.4.24 / Mettler TMA	0°C to 100°C	29
CTE — Z Axis (ppm/°C)	IPC TM-650 2.4.24 / Mettler TMA	0°C to 100°C	217
Tensile Modulus — X/Y (kpsi)	ASTM D-638	A, 23°C	485 / 346
Tensile Strength — X/Y (kpsi)	ASTM D-882	A, 23°C	14.9 / 11.2
Compressive Modulus (kpsi)	ASTM D-695	A, 23°C	327
Flexural Modulus (kpsi)	ASTM D-790	A, 23°C	437
Specific Gravity (g/cm³)	ASTM D-792 Method A	A, 23°C	2.26
Thermal Conductivity (W/mK)	ASTM E-1225	100°C	0.257
Typical Peel Strength (lbs/in)	IPC TM-650 2.4.8	35 µm foil	14

Comparing these figures to DiClad 522 and DiClad 880 reveals DiClad 870’s positioning clearly. The X-axis CTE of 17 ppm/°C (versus 14 ppm/°C for DiClad 522 and 25 ppm/°C for DiClad 880) shows it sitting squarely in the middle of the series. The tensile modulus of 485 kpsi (X-axis) is lower than DiClad 522’s 706 kpsi but substantially higher than DiClad 880’s 267 kpsi — DiClad 870 is less rigid than the highly reinforced 522 series, but it’s not the soft, fragile material that DiClad 880 becomes. In practice, a fabricator with PTFE handling experience will process DiClad 870 without major difficulty.

The Z-axis CTE of 217 ppm/°C is the key reliability parameter for through-hole plating and blind/buried via designs in multilayer constructions. Like all PTFE-based laminates, DiClad 870 has a high Z-axis CTE compared to FR-4 (typically 50–70 ppm/°C). This means via barrel fatigue under thermal cycling needs to be addressed with adequate copper plating thickness — IPC-6012 Class 3 via requirements are the appropriate reference for high-reliability designs.

DiClad 870 NASA Outgassing Data

Parameter	DiClad 870 Result	NASA Limit
Total Mass Loss (TML)	0.02%	< 1.00%
Collected Volatile Condensable Material (CVCM)	0.00%	< 0.10%
Water Vapor Regain	0.01%	—
Visible Condensate	None	None

DiClad 870 clears the NASA ASTM E595 outgassing requirements with substantial margin. For satellite programs, space-borne instruments, or any application where outgassing onto optical or sensor surfaces is a concern, this qualification data is worth having documented in your material selection record.

Understanding DiClad 870’s Medium Fiberglass/PTFE Ratio

The fiberglass/PTFE ratio is the core engineering lever behind every product in the DiClad series, and understanding it helps you make smarter material selections across the family.

Higher fiberglass content pushes the Dk up (glass has a higher dielectric constant than PTFE), improves mechanical rigidity, reduces CTE in the X and Y axes, and makes the material easier to drill and handle. Lower fiberglass content does the opposite: Dk drops toward the PTFE-only value of roughly 2.1, Df falls because PTFE is intrinsically very low loss, but the material becomes softer, more dimensionally prone to movement, and harder to fabricate consistently.

DiClad 870 lands at a medium fiberglass/PTFE ratio. The result is a Dk of 2.33 — lower than the DiClad 522/527 range (2.40–2.65), higher than DiClad 880 (2.17–2.20). The dissipation factor of 0.0013 at 10 GHz is similarly intermediate: better than DiClad 522/527’s 0.0022 at 10 GHz, not quite as good as DiClad 880’s 0.0009. For the majority of RF and microwave applications operating in the 1–40 GHz range, the Df of 0.0013 is more than adequate — the step from 0.0022 to 0.0013 is a real and measurable improvement in insertion loss performance; the further step from 0.0013 to 0.0009 (DiClad 880) is a smaller incremental gain that comes with harder fabrication.

Arlon DiClad 870 Available Thicknesses and Copper Options

DiClad 870 is available in master sheet sizes of 36″×48″, 36″×72″, and 48″×54″. It is supplied clad with copper on both sides as standard. Available thicknesses and copper foil configurations include:

Core Thickness (mil)	Core Thickness (mm)	Standard Copper Weights
31 mil	0.787 mm	½ oz (18 µm), 1 oz (35 µm), 2 oz (70 µm)
93 mil	2.286 mm	1 oz (35 µm), 2 oz (70 µm)
125 mil	3.175 mm	1 oz (35 µm), 2 oz (70 µm)

Standard copper foil is electrodeposited (ED). Rolled copper foil and heavier weights (3 oz+) are available on request. DiClad 870 is also available bonded to a heavy metal ground plane — aluminum, brass, or copper — which adds structural support and provides an integral heat sink for applications where thermal management is a parallel concern alongside RF performance.

For high-frequency designs above 15 GHz, specifying rolled or low-profile copper foil is worth the conversation with your fabricator. At these frequencies, the skin effect concentrates current at the outer few microns of the conductor surface, and standard ED copper’s surface roughness starts contributing measurably to conductor loss. Low-profile foil options reduce this contribution significantly.

It is worth noting that DiClad 870 is not as widely available in thin core configurations as DiClad 527. If your stack-up requires cores below 31 mil, DiClad 527 (which goes down to 5 mil / 0.127 mm) is the DiClad family answer. DiClad 870’s thickness range begins at 31 mil (0.787 mm), making it more appropriate for standard two-layer boards, thicker cores in multilayer constructions, or applications where the substrate serves a structural role alongside its RF function.

Key Benefits of Arlon DiClad 870

Lower Dk Than DiClad 522/527. The Dk of 2.33 means wider trace widths for a given characteristic impedance compared to DiClad 522/527 (Dk 2.40–2.65). Wider traces have lower resistance for a given trace thickness, which is a real advantage in power-handling circuits and in situations where trace resistance contributes to resistive loss or thermal rise.

Better Dissipation Factor Than DiClad 522/527. At 10 GHz, Df of 0.0013 vs 0.0022 — a 41% reduction in loss tangent. In a 100mm microstrip run, this difference is easily measurable with a VNA. In a complex feed network with multiple wavelengths of trace, the difference in insertion loss accumulates to a point where it directly affects system performance.

Frequency-Flat Dk. The Dk of 2.33 is constant from 1 MHz to 10 GHz and remains stable into the millimeter-wave range. Frequency-independent Dk simplifies wideband and multi-band circuit design considerably.

Better Mechanical Properties Than DiClad 880. With a tensile modulus of 485 kpsi (versus DiClad 880’s 267 kpsi), DiClad 870 handles better in drilling, routing, and lamination. For fabricators used to working with DiClad 522/527, the transition to DiClad 870 requires minimal process adjustment.

UL94V-0 Flammability Rating. Required for most military, commercial avionics, and industrial program qualifications. DiClad 870 carries this rating.

Low Water Absorption. At 0.02%, DiClad 870 absorbs slightly less moisture than DiClad 522/527 (0.03%), contributing to more stable electrical performance across humidity environments and simplifying pre-bake protocols before assembly.

NASA Outgassing Qualified. TML of 0.02% and CVCM of 0.00% qualifies DiClad 870 for spacecraft and satellite applications under ASTM E595.

Primary Applications for Arlon DiClad 870

DiClad 870 is used across a wide range of high-frequency PCB applications where the 522/527 series Dk is too high, but the mechanical demands of the design rule out the softer DiClad 880.

Military Radar Feed Networks and Phased Array Systems

Radar feed networks demand both low insertion loss across the feed path and excellent Dk uniformity across the panel to maintain phase coherence between array elements. DiClad 870’s lower Df compared to DiClad 522 makes it attractive for long feed paths where accumulated loss would otherwise consume a meaningful portion of the system’s signal budget. The woven fiberglass reinforcement maintains the Dk uniformity and dimensional stability that large-format radar panels require.

Low-Loss Base Station Antennas

Commercial cellular infrastructure — from 4G macro cells to 5G millimeter-wave units — uses high-frequency feed networks where every fraction of a dB in the antenna feed path directly reduces effective radiated power and system efficiency. DiClad 870’s Df of 0.0013 is well-suited to base station antenna combiner and feed network design.

Filters, Couplers, and Diplexers

Bandpass filters, directional couplers, and diplexers in the 1–40 GHz range are among the most sensitive applications in terms of dielectric constant uniformity. A Dk that varies across the panel shifts resonant frequencies and coupling coefficients away from design values. DiClad laminates, including the 870, are specifically cited for filter, coupler, and low-noise amplifier applications where Dk uniformity is critical.

Power Dividers and Combiners

Low loss is a hard requirement in power combiners — loss that doesn’t go to the load becomes heat at the combiner, reducing efficiency and potentially causing thermal management problems. DiClad 870’s Df of 0.0013 at 10 GHz keeps combiner insertion loss minimal.

Satellite and Aerospace Hardware

The NASA outgassing data and UL94V-0 rating make DiClad 870 a qualified candidate for space-borne and airborne RF assemblies. Its stable Dk over the –10°C to +140°C range (TcDk = –161 ppm/°C) covers the thermal profile of many satellite operating environments.

WiFi and Digital Radio Antennas

Commercial antenna designs for WiFi (2.4 GHz, 5 GHz, 6 GHz) and digital radio infrastructure benefit from a substrate with a stable, low Dk. The lower Dk of DiClad 870 versus common PCB materials also allows physically compact antenna elements to achieve the correct electrical length without needing to scale dimensions as aggressively as with higher-Dk substrates.

Arlon DiClad 870 vs. DiClad 880 vs. DiClad 522/527: The Whole Family in One View

Understanding how DiClad 870 sits within the full DiClad family is the fastest way to know whether you’re looking at the right product.

Parameter	DiClad 522/527	DiClad 870	DiClad 880
Fiberglass/PTFE Ratio	High	Medium	Low
Dk @ 10 GHz	2.40 – 2.65	2.33	2.17, 2.20
Df @ 10 GHz	0.0022	0.0013	0.0009
Df @ 1 MHz	0.0010	0.0009	0.0008
CTE — X Axis (ppm/°C)	14	17	25
CTE — Z Axis (ppm/°C)	173	217	252
Tensile Modulus X (kpsi)	706	485	267
Specific Gravity	2.31	2.26	2.23
Water Absorption (%)	0.03	0.02	0.02
Min Thickness Available	0.005″ (DiClad 527)	0.031″	Similar to 870
Relative Mechanical Rigidity	Highest	Medium	Lowest
Relative Fabrication Ease	Easiest	Moderate	Hardest

The pattern is clear and logical: as fiberglass content drops across the DiClad family, Dk and Df both improve, but mechanical rigidity and fabrication ease both decrease. DiClad 870 is the balanced middle option.

Arlon DiClad 870 vs. Rogers RT/duroid 5880: Head-to-Head

Rogers RT/duroid 5880 is the most commonly cited PTFE-glass PCB material in competitive evaluations, so a direct comparison is useful.

Parameter	Arlon DiClad 870	Rogers RT/duroid 5880
Glass Reinforcement	Woven fiberglass	Random glass microfibers
Dk @ 10 GHz	2.33	2.20
Df @ 10 GHz	0.0013	0.0009
Water Absorption (%)	0.02	0.02
CTE — X Axis (ppm/°C)	17	31
Dimensional Stability	Better (woven glass)	Lower (random fibers)
Mechanical Rigidity	Higher	Lower (softer)
Fabrication	More forgiving	Requires more care
Availability (thin cores)	31 mil minimum	Down to 5 mil

RT/duroid 5880 offers a lower Dk (2.20 vs 2.33) and a lower Df (0.0009 vs 0.0013), so it provides wider traces and marginally lower insertion loss. However, its random glass microfiber structure makes it softer and less dimensionally stable than DiClad 870’s woven glass construction. The X-axis CTE of 31 ppm/°C for RT/duroid 5880 versus 17 ppm/°C for DiClad 870 illustrates the dimensional stability difference directly. If your fabrication process or stack-up demands better dimensional control — or if your yields with RT/duroid 5880 are suffering from registration issues — DiClad 870 is worth trialing as an alternative.

DiClad 870 vs. Rogers RO4350B: When to Use Which

Parameter	Arlon DiClad 870	Rogers RO4350B
Base Chemistry	PTFE / Woven glass	Hydrocarbon ceramic thermoset
Dk @ 10 GHz	2.33	3.48
Df @ 10 GHz	0.0013	0.0037
Processing	PTFE-specific	FR-4-like
Cost	Higher	Lower
Typical Use Range	1 GHz to 40+ GHz	Up to ~15–20 GHz

RO4350B wins on cost and processability — almost any PCB shop can handle it without special PTFE procedures. But the Dk of 3.48 means narrow traces, and the Df of 0.0037 is nearly three times higher than DiClad 870 at 10 GHz. For budget-constrained commercial designs below 10 GHz where insertion loss is not a first-order constraint, RO4350B is a reasonable choice. For designs above 15 GHz, loss-sensitive circuits at any frequency, or applications requiring the lowest Dk for maximum trace width, DiClad 870 is the stronger performer.

PCB Fabrication Considerations for Arlon DiClad 870

DiClad 870 requires PTFE-aware fabrication processes. Anyone who has built DiClad 522/527 boards will not find DiClad 870 significantly different — the process steps are the same; the material is slightly softer and requires marginally more care in handling, but it is substantially easier to work with than the lightly reinforced DiClad 880.

Drilling

Use sharp, new carbide drill bits, reduce feed rate and spindle speed from your FR-4 parameters, and limit hit count per bit significantly compared to FR-4 targets. Entry and exit backing material should be used to support the laminate during drilling and minimize burring. Clean hole walls are critical — ragged holes in PTFE reduce plated through-hole reliability.

PTFE Surface Activation Before Plating

This is non-negotiable. PTFE surfaces are chemically inert and will not bond to electroless copper without surface activation. Standard approaches are sodium naphthalene chemical etching or plasma etching. Your fabricator must have a validated, documented activation process. Incomplete activation leads to pad delamination and via barrel failures that typically emerge during or after thermal cycling — the worst possible time to find a process problem.

Pre-Bake Before Assembly

Pre-bake boards at 105°C for 2–4 hours before reflow soldering. DiClad 870’s water absorption of 0.02% is extremely low, but even trace moisture in a PTFE laminate will create steam during the rapid temperature ramp of a reflow profile, potentially causing micro-voids or delamination at the copper-PTFE interface. Pre-baking eliminates the risk entirely at minimal cost.

Impedance Control

DiClad 870 has a single, fixed Dk of 2.33 — unlike DiClad 522/527 where you must specify which Dk value (2.40, 2.50, 2.55, or 2.60) your batch is. This actually simplifies impedance control: your field solver uses 2.33, full stop. Request the actual measured Dk certificate from your material lot for the most accurate impedance calculation, but the single-Dk nature of DiClad 870 removes one variable from your stack-up planning.

Working With a Qualified Fabricator

Not all PCB shops carry UL certification for specialty microwave substrates, and not all maintain PTFE-specific process documentation. Fabricators without documented PTFE experience introduce yield and reliability risks that are entirely avoidable. Selecting a specialist in microwave PCB fabrication is the single most important process decision for DiClad 870 designs.

For expert sourcing, stackup design support, and manufacturing with DiClad 870 and the full Arlon laminate range, working with an experienced Arlon PCB manufacturer saves significant development time and avoids process-related yield losses.

Useful Resources for Engineers Working With Arlon DiClad 870

Resource	Description	Link
DiClad 522/527/870/880 Official Datasheet (PDF)	Original Arlon datasheet with full comparative spec table for all DiClad variants	docs.rs-online.com (PDF)
Arlon Microwave Materials Guide (PDF)	Complete Arlon product line guide including DiClad, CuClad, CLTE, IsoClad	integratedtest.com (PDF)
MatWeb DiClad 870 Material Entry	Searchable material property database entry with key DiClad 870 parameters	matweb.com
LookPolymers DiClad 870 Page	Aggregated property overview for Arlon DiClad 870	lookpolymers.com
Rogers DiClad 870/880 Product Page	Rogers Corporation official DiClad 870/880 product page with laminate properties tool	rogerscorp.com
Arlon EMD Official Site	Manufacturer’s technical documentation and product catalogue portal	arlonemd.com
PCB Directory DiClad 870 Entry	Product listing with datasheet download request for DiClad 870	pcbdirectory.com

Frequently Asked Questions About Arlon DiClad 870

1. When should I choose DiClad 870 over DiClad 522 or DiClad 527?

Choose DiClad 870 when your design needs a Dk below 2.40 and a lower loss tangent than DiClad 522/527 provides, but you don’t want to accept the mechanical softness and fabrication challenges of DiClad 880. In practice, this means DiClad 870 is the right choice when: (a) your impedance model benefits from the wider traces that a Dk of 2.33 produces, (b) your insertion loss budget is tighter than DiClad 522/527 can satisfy at your operating frequency, or (c) your fabricator has limited PTFE experience and you want a more mechanically forgiving option than DiClad 880. If your current design uses DiClad 522 and you’re marginal on insertion loss, trialing DiClad 870 is the first step before going all the way to DiClad 880.

2. What is the trace width for 50-ohm microstrip on DiClad 870 at standard thicknesses?

For a 31 mil (0.787 mm) core with 1 oz copper (35 µm) and Dk 2.33, a 50-ohm microstrip trace is approximately 2.4 mm (94 mil) wide using standard microstrip formulas. Compare this to the same stack-up on DiClad 522 with Dk 2.50 — the 50-ohm trace there is approximately 2.25 mm (89 mil). The Dk 2.33 of DiClad 870 produces roughly 7% wider traces, which reduces conductor resistance and is directly beneficial in power-handling or low-loss applications. Always confirm with a field solver (Sonnet, HFSS, or Keysight ADS LineCalc) using your actual fabricated copper thickness.

3. Can DiClad 870 be used in mixed-dielectric multilayer PCBs with FR-4?

It is technically possible, but the CTE mismatch between DiClad 870 (Z-axis CTE 217 ppm/°C) and FR-4 (Z-axis CTE 50–70 ppm/°C) means the hybrid stack-up will experience interfacial stress under thermal cycling. Reliability depends on the lamination bond chemistry, the thermal cycling profile, and the presence or absence of plated through-holes spanning the PTFE-FR4 interface. If a hybrid stack-up is required, work with a fabricator that has specific experience in PTFE/FR-4 hybrids, use compatible bonding plies, and plan for qualification testing (thermal shock, thermal cycling) appropriate to your program’s reliability requirements.

4. Is DiClad 870 suitable for millimeter-wave designs above 30 GHz?

DiClad 870 performs well into the Ka-band (26.5–40 GHz) and beyond, with the caveat that conductor loss (rather than dielectric loss) becomes the dominant loss mechanism above roughly 20 GHz due to the skin effect. At Ka-band, specifying low-profile or rolled copper foil is important to keep conductor losses in check. The glass weave periodicity effect — where the regular structure of woven glass creates local Dk variations that can scatter high-frequency signals — is present in DiClad 870 as in all woven-glass laminates, and becomes a consideration at V-band (50–75 GHz) and above. For frequencies above 50 GHz, non-woven or ceramic-filled substrates may offer better phase consistency across large panel areas.

5. How does DiClad 870’s Dk stability over temperature compare to other RF laminates?

DiClad 870 has a thermal coefficient of Dk (TcDk) of –161 ppm/°C, measured from –10°C to +140°C. Across a standard industrial operating range of –40°C to +85°C (a 125°C span), the Dk shift is approximately 0.020 — small but nonzero. For temperature-compensated oscillators or narrowband filters where center frequency stability is the primary design constraint, this Dk shift must be included in your worst-case frequency drift analysis. For most broadband RF circuits, the shift is well within acceptable tolerances. By comparison, Rogers RO4350B has a TcDk of approximately +50 ppm/°C, meaning its Dk increases with temperature — the opposite direction to PTFE laminates, which is a useful fact if you’re designing hybrid boards and need to understand how the dielectric mix behaves across temperature.

Conclusion

Arlon DiClad 870 is the DiClad series answer to the design problem of “I need lower loss than DiClad 522 can offer, but I can’t afford the mechanical compromises of DiClad 880.” Its medium fiberglass/PTFE ratio lands on a Dk of exactly 2.33 — stable, flat, and consistent across frequency — paired with a dissipation factor of 0.0013 at 10 GHz that represents a genuine 41% improvement in loss tangent over DiClad 522/527. The mechanical properties remain solid enough for standard PTFE fabrication practices. The NASA outgassing data qualifies it for space-borne hardware. The UL94V-0 rating covers most commercial and military program requirements.

For engineers upgrading from DiClad 522/527 because their insertion loss margin is becoming a problem, DiClad 870 is the most logical first step. It requires no fundamental changes to your fabrication process, delivers measurably lower loss, and gives you slightly wider traces as a bonus. For sourcing, stack-up consultation, and fabrication by shops experienced with Arlon laminates, connecting with a specialist in Arlon PCB manufacturing is the practical next step.