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A useful ITEQ directory keeps the conditions beside the grade

ITEQ PCB materials span conventional epoxy laminates, reliability-focused constructions and lower-loss material families. Selecting one requires more than finding the largest Tg or smallest Df. The material name, measurement method, frequency, resin content and construction must remain attached to the value. This directory gives an eight-grade verified reference set and a route to the wider manufacturer portfolio; it does not claim every grade or every construction is included.

Use the table to identify candidates, then ask for the current construction-specific data and availability. Manufacturing approval, quantities and quotation are handled on the separate ITEQ PCB manufacturing page. This division keeps material research distinct from an order for a finished board. Neither a search result nor a filter match means that the material is approved for your design.

The references below were checked against official web tables on September 27, 2026. Those summary pages do not display a document revision for each table. Preserve a controlled data-sheet revision with the eventual purchase specification. Where a summary and a detailed data sheet report different test conditions, compare their definitions before treating the numbers as conflicting measurements.

Eight documented grades, two electrical comparison groups

Electrical values in this table are reported at 10 GHz using IPC-TM-650 2.5.5.13. The first four grades use 50% resin content; the other four use 70%. Tg methods are shown separately. These are manufacturer reference values, not purchase acceptance limits or a universal set of design Dk values. Exact glass style, conditioning, foil and specimen construction are not fully specified by the summary table.

The supports the conventional entries. The and support the other entries. Follow the individual record鈥檚 source rather than searching for an unrelated data sheet with a similar filename.

Filter within a stated data set

The material filter lets you choose a resin-content group, a Tg method and numeric thresholds. It reports the records that satisfy those entered limits. A DSC threshold is never silently applied to a TMA result. If the filter returns no result, that means no record in this small verified set satisfies the selected conditions; it does not mean ITEQ has no suitable product.

Start with the data you genuinely require. If the electrical requirement is a loss budget, do not substitute a generic Tg target for it. If the requirement is thermal endurance, a low Df is not an endurance test. After filtering, compare the full construction and source evidence. The result does not rank materials, calculate a total channel loss, certify a halogen declaration or check local stock.

For an example of method discipline, IT-180A is listed with a DSC Tg while several low-loss records use TMA. A user who wants to compare DSC results must obtain DSC data for the other candidate rather than inserting its TMA value in the same column. The tool makes that limitation visible instead of treating all temperature numbers as interchangeable.

How the broader portfolio differs from this directory

The also lists families such as IT-170GT, IT-170GRA2, IT-958G, IT-998GSE and IT-999GSE3. Their presence on a roadmap establishes a product-family reference, not the exact construction needed for your board. This page does not fill missing method or construction fields with values from adjacent models.

A catalogue may organize grades by market category, while your selection depends on several intersecting requirements. A networking board may need channel-loss control, repeated assembly exposure and a mechanically stable high-layer-count construction. A power-control board may instead be dominated by insulation, copper geometry and thermal cycling. A family marketed for one application is not automatically excluded from another, but the actual evidence must follow the new use.

Suffixes deserve particular attention. Changes in glass reinforcement, resin chemistry or product format may be encoded in a suffix, but that convention must be confirmed for the specific family. Do not build a universal rule that strips letters from material names. Retain the manufacturer鈥檚 full designation in both the CAD material record and the approved purchasing list.

A laminate family and its prepreg are related but different physical products. The cured core has a defined dielectric construction and copper faces. Prepreg contains a partially cured resin system that bonds layers during pressing. The ITEQ prepreg selection guide explains how resin content, ply construction and pressed dimensions belong in the material assignment.

Turn a candidate into an engineering comparison

Write down the reason for considering a change. Is the channel losing too much signal, is the stack too thick, is an approved thickness unavailable, or is the assembly exposure changing? Each reason requires a different comparison. A purchasing-only substitution that changes the dielectric construction can become a layout change even when the board outline remains fixed.

For electrical comparison, retain the test frequency, method, resin content and the intended use of the value. An effective permittivity extracted from a transmission line is not necessarily the same quantity as a bulk laminate reference. Foil roughness, weave distribution and geometry affect the finished interconnect. Use the condition-matched Dk and Df comparison before applying a material number to an electrical model.

For thermal comparison, record the test method and the response being measured. Glass transition, decomposition and time to delamination describe different phenomena. A high Tg does not define the continuous operating temperature of an assembled product. Component ratings, attachment materials, electrical stress, environment and life requirements remain part of the system decision.

For procurement comparison, request compatible core and prepreg constructions, copper options, panel format and a controlled substitution policy. Two quotations based on different constructions are not directly comparable merely because both use the ITEQ brand. State which alternatives are allowed and which dimensions or tests must be repeated before an alternative can be released.

A shortlist can reveal a missing requirement

Suppose a team filters the 50% resin-content group by a DSC Tg of at least 170掳C and a maximum reported Df of 0.018. More than one reference can survive that numeric screen. That does not answer whether the proposed core thickness is available, whether the chosen prepreg fills the copper pattern or whether the channel meets its loss budget. The useful output is a shorter set of questions, not an approved winner.

Now suppose the engineer switches to the 70% group to explore lower Df. That is a new comparison basis. A percentage improvement calculated across the two groups would combine a material-family change and a construction-related resin-content change. Preserve those differences instead of presenting the result as an intrinsic brand ranking. The filter records the selected group in its downloadable brief.

The next document should name a candidate and the missing evidence. Include the exact source, requested glass and copper, provisional thickness and applicable electrical or thermal requirements. Keep the author鈥檚 assumptions separate from supplier-confirmed data. When the manufacturer returns a stackup, update the actual layer assignment and test scope rather than merely replacing a material name in the title.

Keep the material record usable after the first build

A material-selection record should survive the handoff from engineering to purchasing and receiving inspection. Save the source document revision, the approved construction and the reason for selection. Keep the finished-board drawing revision beside it. If a replacement source is introduced later, the original acceptance basis should be recoverable without relying on the memory of the first project engineer.

Avoid making unsupported claims in internal part descriptions. 鈥淟ow loss,鈥� 鈥渉igh reliability鈥� or 鈥渁utomotive鈥� can be useful categories, but they are not a substitute for the actual requirement or evidence. Likewise, an image of a green board cannot establish its laminate identity. The photographs on this page illustrate material and board forms; they are not proof that the pictured items use any grade in the table.

The approved ITEQ stackup design should tie the record to physical layers. A change in resin content, foil or prepreg construction may require electrical and manufacturing review even when the headline material family stays the same. Document those changes before asking the purchasing team to treat two orders as equivalent.

Material directory questions