Technical Overview of Glazing Types Used in Display Case Manufacturing

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The selection of glazing for a display case is a critical engineering decision that directly affects structural performance, optical quality, conservation capability, and security. While many commercial environments still rely on standard tempered panes, museum-grade and high-security applications demand sophisticated, multi-layered glass systems engineered to precise performance criteria.

This technical overview examines the primary glazing types used in display case manufacturing, including recommended thicknesses, performance characteristics, and their suitability for specific applications.

1. Float (Annealed) Glass

Float, or annealed, glass is produced by floating molten silica-based glass on a tin bath, resulting in uniform thickness and excellent surface flatness.

Typical thickness range:

  • 3–8 mm for general retail and lightweight displays
  • 10 mm+ rarely specified due to weight and lack of safety performance

Technical characteristics:

  • Modulus of rupture: approximately 45 MPa
  • No post-production strengthening
  • Breaks into large, hazardous shards
  • UV protection typically around 25–40%, depending on composition

Use case: Limited to low-risk displays where safety, security, and conservation are not primary considerations.

2. Thermally Tempered Glass

Tempered glass is manufactured by heating annealed glass to approximately 620°C and rapidly cooling it to induce surface compression stresses.

Typical thickness range:

  • 6, 8, 10, and 12 mm for commercial and retail display cases

Technical characteristics:

  • Surface compressive stress exceeding 90 MPa
  • Approximately four to five times stronger than float glass
  • Breaks into small cuboid fragments in compliance with EN 12150
  • Limited resistance to focused forced entry
  • No inherent UV filtration

Use case: Retail environments requiring safety compliance but not enhanced security or conservation performance.

3. Laminated Safety Glass (PVB or SGP Interlayers)

Laminated glass consists of two or more glass panes bonded together using polymer interlayers such as polyvinyl butyral (PVB) or ionoplast (SGP / SentryGlas®).

Common configurations:

  • 6.4 mm (3 mm + 0.4 mm interlayer + 3 mm)
  • 8.8 mm (4 mm + 0.8 mm interlayer + 4 mm)
  • 10.8 mm, 12.8 mm and above for increased stiffness and security

Technical characteristics:

  • Post-breakage integrity due to interlayer adhesion
  • SGP interlayers offer approximately five times the stiffness and significantly higher tear resistance than PVB
  • UV-blocking performance up to 99% with appropriate interlayer formulations
  • Improved acoustic damping
  • Compliance with EN 14449

Use case: Jewellery counters, mid- to high-value retail, and museum applications requiring structural stability, moderate security, and UV protection.

4. Low-Iron Museum-Grade Laminated Glass

For conservation display cases, both optical performance and protective characteristics are critical.

Typical system characteristics:

  • Low-iron substrates to minimise iron oxide content and reduce green edge tint
  • Anti-reflective coatings applied via magnetron sputtering, achieving reflectance values below 1% per surface
  • Museum-grade UV-blocking interlayers targeting at least 98% filtration between 300–380 nm
  • Laminated construction providing enhanced stiffness and security for large panels

Museum-grade glazing is engineered to align with conservation standards such as ISO 3664 and CIE UV exposure guidance.

Use case: High-value museum artefacts, sensitive organic materials, and installations requiring colour fidelity and preservation-grade UV protection.

5. Anti-Bandit (Attack-Resistant) Glass

Anti-bandit glazing is a multi-layer laminated system tested to EN 356 classifications (P6B–P8B) for manual attack resistance.

Construction:

  • Multiple glass layers laminated with thick PVB or SGP interlayers

Technical characteristics:

  • P6B rating resists approximately 30–50 strikes
  • P8B rating resists 70 or more strikes
  • High residual strength after initial fractures
  • Provides critical time delay during attempted theft

Use case: High-risk retail environments and museum installations requiring enhanced anti-theft protection.

6. Bullet-Resistant Glass

Bullet-resistant glazing is an engineered composite of glass and polycarbonate, tested to EN 1063 (BR1–BR7) or UL 752 standards.

Construction:

  • Alternating layers of glass and polycarbonate bonded with polyurethane
  • Total thickness typically ranges from 24 mm to over 80 mm, depending on threat level

Technical characteristics:

  • Progressive energy absorption through controlled delamination
  • Exceptional forced-entry resistance after ballistic impact
  • High weight requiring structurally engineered case systems

Use case: Government facilities, high-security museums, and specialised installations where ballistic threats must be mitigated.

7. UV-Protective Coatings and Specialty Films

UV protection is critical in conservation environments due to cumulative photochemical degradation.

Key metrics:

  • Standard float glass: approximately 38% UV filtration
  • Laminated glass with UV interlayer: up to 99%
  • Museum-grade AR and UV coatings: typically 96–99%
  • Low-E coatings: partial UV reduction only

Technical considerations:

  • Avoid coatings that significantly reduce visible light transmission
  • Confirm compatibility with display case microclimates
  • Assess long-term stability and off-gassing behaviour

Security Performance Summary

Float glass offers minimal resistance, tempered glass improves safety but not security, laminated systems provide moderate to high protection, anti-bandit glass delivers strong forced-entry resistance, and ballistic glass offers the highest level of security.

Conclusion and Professional Consultation Recommendation

Selecting the correct glazing system for a display case is never a one-size-fits-all decision. Optimal specification depends on security risk, conservation requirements, optical performance, structural constraints, and project budget.

Because these factors interact in complex ways—particularly in museum and high-security environments—professional consultation is strongly recommended when finalising glazing specifications.

If you are planning a museum installation or a secure display environment, specialist advice can help ensure the correct balance of protection, performance, and practicality.