Mould Release For Glass Pressing That Does Not Mark The Ware
A glass press cycle puts molten glass onto a hot steel mould and plunger, and the ware has to drop out clean every time. Most plants swab or spray a white release agent and reapply it every few hours; the trade-off is build-up, matte patches on the ware and downtime. Hexagonal boron nitride suits this duty better than anything else because molten glass does not wet it, it is white, it carries no carbon and it keeps lubricating at mould temperature. Pyroflux India makes a three-part BN system for glass pressing in Noida: Pyrolube 25MG as a bonded base coat applied at mould change, Pyrolube 10G as a light top-up during production, and Pyrolube Nano 20 for borosilicate moulds where transparent ware must stay transparent. The aerosol covers shears, guides and small tooling.
Why Single-Spray Release Runs Out Of Road
A release agent sprayed on a hot mould every few hours builds up: each coat goes on over the last, the film thickens unevenly, and the ware starts to show matte patches and seams. Shortening the interval makes build-up worse; lengthening it brings sticking back. The fix is to separate the two jobs. A bonded base coat, applied once at mould change on a clean, preheated mould, does the adhesion. A light top-up during production, swabbed or sprayed, renews release without adding thickness.
Transparent borosilicate adds a third problem: a conventional BN film, however thin, makes clear ware matte. A nano-scale h-BN dispersion releases without dulling the surface, which is why the glass system has a third grade.
Three Grades, One Routine
| Step | Grade | When | Ware |
|---|---|---|---|
| Base coat | Pyrolube 25MG | At mould change: clean, preheat, coat, cure as the mould comes up to temperature | Opal, borosilicate |
| Top-up | Pyrolube 10G | During production, swab or spray at the line’s interval | Opal, borosilicate |
| Transparent ware | Pyrolube Nano 20 | On cleaned, preheated moulds, diluted as directed, cured to working temperature, lightly buffed | Borosilicate |
| Shears, guides, small tooling | BN aerosol | Touch-ups | Any |
Full grade details, the step-by-step Nano 20 procedure and the FAQ are on the Pyrolube glass mould release page.
How a Glass Trial Runs
- Tell us the glass (opal or borosilicate), mould and plunger temperatures, mould steel and finish, and whether you swab or spray during production.
- We send a trial set of the base coat and top-up (and Nano 20 for transparent ware) with the written application procedure.
- Run one mould set through a mould change and a full production interval; compare ware surface, sticking and interval against your current spray.
- Set the top-up interval from what the line shows, then roll out.
Common Questions
Will boron nitride mark the glass?
No. Opal ware runs clean on the base coat and top-up. Transparent borosilicate needs the nano grade, Pyrolube Nano 20, because a conventional BN film makes clear glass matte.
Can we keep swabbing during production?
Yes. Pyrolube 10G is made for swabbing or spraying during production; nothing changes on the machine.
What mould temperatures does the system cover?
It covers the mould and plunger temperatures normally used for pressed tableware, and the coatings are stable well above that range.
Do you supply a technical data sheet and SDS?
Yes, for all three grades, by email within one working day of a request.
Tell Us The Process; We Will Recommend The Grade
Substrate, process temperature, atmosphere and how you prefer to apply it. That is everything we need to point you at the right product, send a sample, or quote.
- Phone
- +91 98181 87838
- sales@pyroflux.in
- Office
- G-5, Sector 63, Noida 201301, Uttar Pradesh, India
- Factory
- G-15, Sector 63, Noida 201301, Uttar Pradesh, India
- Hours
- Monday to Saturday, 9 am to 6 pm IST