# Resources Six guides, each with the notes underneath it. Every note answers one question a buyer has actually asked, with the numbers from the data sheet rather than adjectives. Factory, Wei County. PU versus silicone: where each family belongs. Construction sealant family. 10 pages · 9 notes ## Windscreen adhesive Bead geometry, modulus, primerless systems and the failures that come back. [Windscreen adhesive: the specification guide](https://karmindadhesive.com/resources/windscreen-adhesive-guide/) — the guide - [KA518 vs KA520 vs KA530F: choosing a windscreen adhesive](https://karmindadhesive.com/resources/choosing-a-windscreen-adhesive/) — Three PU windscreen grades compared on tensile strength, elongation and skin time — and the four questions that decide which one your bay actually needs. - [Windscreen adhesive cure time: why a bead stays soft](https://karmindadhesive.com/resources/why-windscreen-adhesive-cures-too-slowly/) — Why a bead is still soft the next morning: cold glass, dry air, thick sections and the four reasons a cure runs late, with the arithmetic that predicts it. - [How much windscreen adhesive a car actually takes](https://karmindadhesive.com/resources/windscreen-adhesive-bead-geometry/) — Bead cross-section, cartridge maths and why an 8×10 mm triangle is 40 mm² — the calculation that turns 'one cartridge per car' into a number. - [Primerless windscreen adhesive: what it covers](https://karmindadhesive.com/resources/primerless-windscreen-adhesive/) — Primerless PU adhesives cut a process step, not the preparation. What the claim covers on glass, paint and metal, and where it stops being true. - [Installing windscreen adhesive below 10 °C](https://karmindadhesive.com/resources/windscreen-adhesive-cold-weather/) — Cold glass, slow cure and the two-hour promise that quietly stops being true: what changes below 10 °C and how to keep the bay moving without guessing. - [Bus and coach glazing needs a different windscreen adhesive](https://karmindadhesive.com/resources/bus-coach-windscreen-adhesive/) — Larger glass, more body flex and higher wind load: why a passenger-car adhesive is the wrong specification for a coach, and what the numbers look like. - [Diagnosing a failed windscreen bond](https://karmindadhesive.com/resources/diagnosing-windscreen-bond-failure/) — Peel test, frit reading and bead cross-section: a three-step diagnosis that separates a product failure from a preparation failure, in ten minutes. - [Windscreen adhesive shelf life and storage](https://karmindadhesive.com/resources/windscreen-adhesive-shelf-life/) — Why a cartridge skins over in the nozzle, what heat does to a moisture-curing adhesive, and how to store it so the last cartridge behaves like the first. - [Automotive Windscreen Adhesive Testing Requirements](https://karmindadhesive.com/resources/automotive-windscreen-adhesive-testing/) — What to test on a windscreen adhesive: tensile, elongation, shear, peel, skin, cure, sag and drive-away, with the conditions that make the numbers comparable. 6 pages · 5 notes ## Body seam sealing Sealing versus bonding, sanding and paint compatibility, corrosion at lapped joints. [Body seam sealing: sealer, adhesive or both](https://karmindadhesive.com/resources/body-seam-sealer-guide/) — the guide - [Seam sealer vs structural adhesive: which seam gets which](https://karmindadhesive.com/resources/seam-sealer-vs-structural-adhesive/) — One fills a gap, one carries load. Mixing them up is the most expensive mistake in body repair — how to tell which seam is which before the gun comes out. - [Painting over seam sealer without a comeback](https://karmindadhesive.com/resources/painting-over-seam-sealer/) — Cure window, primer compatibility and the waterborne basecoat trap: why a sealer that passed the thumb test can still ruin a paint job on the car. - [Seam sealer and corrosion at lapped joints](https://karmindadhesive.com/resources/seam-sealer-corrosion/) — Where rust actually starts on a repaired panel, why a bead over a wet seam makes it worse, and the two preparation steps that prevent most comebacks. - [Sealing container and trailer seams: STP or PU](https://karmindadhesive.com/resources/container-trailer-seams/) — Mixed substrates, exterior UV and joints that flex at 80 km/h: why the roof seam and the floor seam of a trailer often need different products. - [Cartridge, sausage or barrel: pack economics](https://karmindadhesive.com/resources/seam-sealer-pack-formats/) — Gun time, waste and changeover: why the cheapest cartridge is rarely the cheapest metre, and which pack format fits which workshop size and throughput. 7 pages · 6 notes ## Construction joints Movement class, joint geometry, backer rod, wet concrete and pressure joints. [Construction joint sealant: movement, geometry and failure](https://karmindadhesive.com/resources/construction-joint-sealant-guide/) — the guide - [Joint design decides whether the sealant works](https://karmindadhesive.com/resources/sealant-joint-design/) — Width-to-depth ratio, backer rod, three-sided adhesion and movement class — the four joint decisions that matter more than the sealant brand. - [Joint movement class: the number that decides the sealant](https://karmindadhesive.com/resources/joint-movement-class/) — How movement is calculated as a percentage of joint width, what ISO 11600 and ASTM C920 classes mean in practice, and why elongation is not the same thing. - [Backer rod sizing and three-sided adhesion](https://karmindadhesive.com/resources/backer-rod-sizing/) — Why a bead bonded on three faces cannot stretch, how to size a backer rod by joint width, and the cheap detail that prevents most joint failures. - [Sealing green and damp concrete: why it fails later](https://karmindadhesive.com/resources/sealing-green-concrete/) — Moisture-curing does not mean you can seal wet concrete. What happens at the interface, how long to wait, and the primer that decides the bond. - [Sealing tunnel and drainage joints under water pressure](https://karmindadhesive.com/resources/tunnel-drainage-joints/) — Where a surface bead stops working and a waterstop starts: pressure, movement and the joint details that keep a tunnel or culvert dry under pressure. - [Cold-weather joint sealing: the double problem](https://karmindadhesive.com/resources/cold-weather-joint-sealing/) — Low temperature slows the cure and opens the joint at the same time — why winter installation needs a different plan, not a different product. 6 pages · 5 notes ## STP and industrial bonding Where silyl-terminated polymer wins, where PU still does, and what primerless really covers. [STP sealant: where it beats PU and where it does not](https://karmindadhesive.com/resources/stp-sealant-guide/) — the guide - [PU sealant vs silicone: which one for which joint](https://karmindadhesive.com/resources/pu-sealant-vs-silicone-sealant/) — PU and silicone compared on adhesion, movement, paintability and UV — with the four joints where the wrong choice usually ends in a comeback. - [MS polymer vs PU for windscreen bonding](https://karmindadhesive.com/resources/ms-polymer-vs-pu-windscreen/) — Why the primerless, solvent-free appeal of MS polymer does not replace polyurethane in direct glazing — and the two cases where it genuinely does. - [Primerless STP claims, tested by substrate](https://karmindadhesive.com/resources/primerless-stp-claims/) — Which substrates genuinely bond without a primer, which need an activator, and the ten-minute coupon test that settles it before a production run. - [Overcoating STP sealant: paint systems and cure windows](https://karmindadhesive.com/resources/overcoating-stp-sealant/) — STP is paintable, but not at any time with any paint. How cure state, coating chemistry and film build decide whether the topcoat stays put. - [STP sealant outdoors: UV, colour and chalk](https://karmindadhesive.com/resources/stp-uv-exterior/) — Why STP survives sunlight better than PU, what still changes on a roof seam after five years, and when a topcoat is still worth the extra step. 5 pages · 4 notes ## PUR wood adhesive Moisture content, clamp time, treated timber and the alternatives. [PUR adhesive for glulam and engineered timber](https://karmindadhesive.com/resources/pur-wood-adhesive-guide/) — the guide - [Moisture content is the PUR adhesive process variable](https://karmindadhesive.com/resources/pur-adhesive-moisture-content/) — Why 8–12% is the working window, how to measure moisture on the shop floor, and what wet or frozen timber does to a glue line that looks fine. - [Clamp time and press scheduling for PUR](https://karmindadhesive.com/resources/pur-adhesive-clamp-time/) — How temperature, moisture and section thickness move the 1–4 hour catalogue range, and how to schedule a press without gambling on the release time. - [Bonding treated and dense timber with PUR](https://karmindadhesive.com/resources/pur-adhesive-treated-timber/) — Preservative treatment, extractives and density change how PUR wets and cures. What to test before a structural run, and which species to watch. - [PUR vs PVAc, MUF and EPI: choosing a wood adhesive](https://karmindadhesive.com/resources/pur-vs-pva-muf-epi/) — Four adhesive families compared on water resistance, creep, gap filling and handling — and the applications where each one actually wins in a plant. 16 pages · 15 notes ## Buying and importing Specification, certificates, MOQ and the documents that decide whether a container clears. [Buying PU sealant from China: how to specify and verify](https://karmindadhesive.com/resources/buying-sealant-from-china/) — the guide - [How to read a sealant data sheet](https://karmindadhesive.com/resources/reading-a-sealant-data-sheet/) — Standard, typical value, method and the difference between a catalogue figure and a batch result — a buyer's guide to the table on every model page. - [Importing PU sealant from China: DG, heat and documents](https://karmindadhesive.com/resources/importing-pu-sealant-from-china/) — Dangerous goods, shelf life, heat in transit and the documents a customs broker asks for — a checklist for a first sealant order from China. - [Why PU sealant costs more than silicone per cartridge](https://karmindadhesive.com/resources/why-pu-sealant-costs-more-than-silicone/) — The cost difference is real but it is not where buyers think: raw material, coverage, rework and the hidden cost of a bead that has to be painted twice. - [Batch certificate vs catalogue value](https://karmindadhesive.com/resources/batch-certificate-vs-catalogue/) — A certificate of analysis is useful only if it names the batch, the method and the measured result. What to ask for, and what a bare certificate is worth. - [MOQ and pack economics: why the number changes per format](https://karmindadhesive.com/resources/sealant-moq-pack-economics/) — Why a cartridge MOQ, a sausage MOQ and a barrel MOQ are different questions, and how to structure a first order that does not leave you with dead stock. - [Ten questions for a sealant factory visit](https://karmindadhesive.com/resources/sealant-supplier-audit-questions/) — What to look at, what to ask, and what the answers reveal: ten questions for a sealant factory visit that separate a plant from a trading company. - [Running a sealant sample trial that means something](https://karmindadhesive.com/resources/sealant-sample-trial/) — Substrate, cure conditions, failure mode and a control: how to test a sample cartridge so the result predicts the production batch you receive. - [PU sealant HS code: 3214.10 or 3506.90?](https://karmindadhesive.com/resources/pu-sealant-hs-code/) — How PU sealant is classified: 3214.10 as a mastic or 3506.90 as an adhesive, the duty difference, and the four documents customs asks for on entry. - [Sealant coverage: cartridges per 100 m of joint](https://karmindadhesive.com/resources/sealant-coverage-per-metre/) — Work out sealant coverage from joint width and depth: ml per metre, cartridges per 100 m, and the waste allowance that stops a job running short. - [EN 15651-1 classes: F-EXT-INT-CC explained](https://karmindadhesive.com/resources/en-15651-classes/) — What the letters on a sealant DoP mean: the four EN 15651 product parts, the F-EXT-INT-CC designation, the movement figure and what CE marking requires. - [Sealant shelf life after opening: what still works](https://karmindadhesive.com/resources/sealant-shelf-life-after-opening/) — Unopened shelf life is printed on the cartridge; opened is the number nobody prints. How long PU sealant lasts after opening, and how to tell it has gone. - [PU Sealant Manufacturer Audit Checklist](https://karmindadhesive.com/resources/pu-sealant-manufacturer-audit-checklist/) — A practical factory audit checklist for importers: legal entity, process control, batch records, test methods, capacity and order-stopping red flags. - [How to Compare PU Sealant Suppliers in China](https://karmindadhesive.com/resources/compare-pu-sealant-suppliers-china/) — Compare Chinese PU sealant suppliers on technical fit, batch evidence, landed cost, communication and risk — not on the lowest FOB quote. - [PU Sealant TDS and COA: How to Verify a Supplier](https://karmindadhesive.com/resources/pu-sealant-tds-coa-verification/) — How to read a PU sealant TDS, match a COA to the carton, check test methods and spot the gaps that make a certificate meaningless. - [PU Sealant Shelf Life and Storage Conditions](https://karmindadhesive.com/resources/pu-sealant-shelf-life-storage/) — How to store PU sealant, read shelf life, judge an opened cartridge and avoid moisture, heat and freezing damage before the batch is used. Have a question the catalogue does not answer? Write to [martin@karmindadhesive.com](mailto:martin@karmindadhesive.com) — the answer may end up here.