Jointion | One Stop Opal Glass Tableware Manufacturer
Why We Make Opal Glass Tableware | Our Story
Before starting Jiancheng in 2008, I spent years working in factories, watching tableware being made piece by piece. I often thought about the families who would eventually eat from these plates and bowls—children having breakfast before school, grandparents sharing dinner with loved ones. It made me wonder: are we truly making something worthy of those moments? When customers started asking for healthier alternatives, I discovered opal glass—pure, made from natural quartz sand, free of lead, cadmium, and bone ash. Back then, very few in China saw its potential. But I saw something simple: a material I would feel comfortable putting on my own family’s table. That was enough for me to begin.
Sixteen years have passed, and that feeling has never changed. Today, our products reach families in over 100 countries, but I still walk through our workshops with the same question in mind: would I give this to my children? Every plate that leaves our facility carries that standard with it. The name “Jiancheng” means “health” and “integrity”—not as a slogan, but as a personal promise. I believe the things we eat from should be as clean and honest as the food itself. This is why we do what we do, and why we will keep doing it for many years to come.
Why People Chose Us | Jointion Brand
Direct Factory Price
No middlemen, no markups. As a manufacturer, we offer competitive pricing directly from our production line—helping you maximize margins without compromising quality.
Customizable/OEM
Your vision, our expertise. We offer full OEM services including custom all opal glass shapes, sizes, colors, patterns, and packaging—tailored to your brand and market needs.
Flexible MOQ
Big or small, we serve all. Whether you're a startup testing the market or an established retailer scaling up, our flexible minimum order quantities make it easy to work with us.
On-time Delivery
Unlike trading companies, we control every step of production. With our own in-house material inventory and direct factory management, we're never dependent on third parties.
The Details That Set Us Apart From Competitors
First Step:Raw material preparation
60-65% High-Purity Quartz Sand
Ensures structural hardness and chemical stability for food-safe, heat-resistant glassware.
Common: 50-55% lower-grade silica with higher impurities.
5-8% Professional-Grade Opacifying Agent
Creates jade-like milky-white luster with smooth tactile quality.
Common: 2-3% basic pigments causing dull, rough finish.
Trace Borax Additives
Optimizes thermal expansion for oven-to-table shock resistance.
Common: Often omitted, increasing thermal shock failure risk.
Certified: FDA, LFGB, GB 4806.5 compliant. Lead-free, cadmium-free, barium-free.
Second step:High-temperature smelting
Pre-melting Zone (1200-1400°C)
Fully-enclosed conveyor ensures contamination-free feeding and uniform heating.
Common: Open-feed systems allowing dust contamination.
Fining Zone (1500°C ±5°C)
Precision temperature control within ±5°C tolerance for consistent quality.
Common: ±15-20°C fluctuation causing batch inconsistency.
Conditioning Zone
Extended settling (several hours) with bottom bubbling for complete homogenization.
Common: Under 1 hour settling, leaving compositional variations.
Forehearth & Feeder Canal
Multi-stage temperature control reduces to ~1100°C along preset curve.
Common: Single-stage cooling causing uneven viscosity.
Third step:Fining &Homogenization Zone
High-Temperature Fining (1500°C, 24-48 Hours)
Extended dwell time eliminates micro-bubbles down to nanometer scale for bubble-free glass.
Common: 8-12 hours, leaving visible micro-bubbles as structural weak points.
Platinum Bubbling System
Inert gas injection creates uniform vertical convection for thorough chemical blending.
Common: Basic mechanical stirring with incomplete homogenization.
Quality Control: Real-time monitoring + lab verification for every batch.
Common: Periodic spot-checks only, allowing defects to pass.
Four Step:Opal Glass Tableware Form Process
Precision Annealing (520°C–470°C)
Ultra-slow cooling at less than 3°C/min eliminates internal thermal stress completely.
Common: 10-15°C/min rapid cooling leaves residual stress causing cracks.
Chemical Strengthening (Premium Lines)
Potassium nitrate immersion at 400°C for 3-6 hours creates 30-50 micron compression layer.
Common: Skipped to save time and cost.
+150%
Impact Resistance vs. Standard Glass
+250%
Flexural Strength for Durability
Five step: Annealing & Strengthening
Precision Annealing (520°C–470°C)
Cooling rate less than 3°C/min allows molecular relaxation, permanently eliminating thermal stress.
Common: 8-12°C/min leaves 30-50% residual stress, shortening lifespan.
Chemical Strengthening (Premium Lines)
Potassium nitrate salt bath at 400°C for 3-6 hours creates dense 30-50μm compression layer.
Common: Typically skipped due to additional time and equipment costs.
Result: +300% impact resistance | +250% flexural strength vs. standard glass.
Standard untreated glass shows 2x higher breakage in commercial use.
Our Company's Growth Story
2008
Jointion was established in Guangdong, China as a specialized opal glass tableware manufacturer. We invested significantly in complete production infrastructure from day one: professional melting furnaces with precise temperature control, automated molding systems, tunnel annealing kilns, and chemical strengthening facilities. Our founder's principle was clear — opal glass quality depends on process consistency. Every piece must meet the same standards for whiteness, translucency, and thermal shock resistance. All products have been lead-free and cadmium-free since establishment, meeting food-contact safety regulations for global markets.
2010
Phase I facility completed with centrifugal molding production line fully operational. This technology produces more uniform wall thickness compared to traditional pressing methods, resulting in better strength-to-weight ratio and consistent product quality across large batches. The integrated facility included quality inspection stations, packaging lines, and warehouse capacity to support container-load shipments. This established our capability for medium-to-high volume OEM manufacturing, serving wholesale buyers and brand partners requiring reliable supply with strict quality consistency.
2014
Received dual certifications: "Provincial Enterprise Technology Center" for our technical expertise in opal glass formulation and process optimization, and "Guangdong Province Clean Production Enterprise" for environmental management. Our facility implements waste heat recovery, water recycling, and emissions controls meeting provincial standards. For international buyers focused on supply chain sustainability, these certifications provide documented evidence of both technical capability and responsible manufacturing practices in opal glass production.
2015
Built second high-end glass-ceramic production line with upgraded automation, significantly expanding monthly capacity. The major milestone was establishing OEM partnership with Corning for their Corelle brand — a global leader in glass tableware. This required passing rigorous supplier audits covering quality systems, production capability, testing protocols, and compliance standards. Working with Corelle specifications elevated our processes to world-class levels, demonstrating that Jointion could meet the most demanding requirements from international brand leaders.
2016
Awarded First Prize of Guangdong Province Scientific and Technological Advancement for our opal glass ceramic manufacturing technology. This provincial recognition validated innovations in optimized glass formulations for improved whiteness and translucency, process improvements that increased yield while reducing energy consumption, and successful industrialization translating R&D developments into stable mass production. The award reflects our commitment to continuous technical improvement rather than maintaining status quo manufacturing methods.
2017
R&D Center designated as "Guangdong Provincial Engineering Technology Research Center for Glass-ceramic Materials." This certification recognizes research capabilities beyond routine product development — including glass composition optimization, crystallization control, and surface treatment technologies. For OEM customers, this translates to stronger technical support for custom development. We work with buyers to develop specific formulations for their requirements rather than simply offering standard catalog products.
2018
Certified as "National Postdoctoral Research Workstation" by China's Ministry of Human Resources, authorizing us to host advanced researchers. Also received Quality Award from Chaozhou Municipal Government — significant recognition within China's major ceramics and glass manufacturing region. We maintain in-house testing laboratories for raw material analysis, performance testing, and quality verification, providing customers with test reports, material certifications, and compliance documentation for their target markets.
2019
Launched three proprietary glass collections developed by our R&D team: black crystal glass, white jade glass, and pink jade glass tableware. Each required separate formulation development and process optimization. Black crystal glass suits hospitality and premium retail; white jade offers warmer tones than standard opal; pink jade targets specific regional preferences. This diversification demonstrates our custom material development capability — valuable for brand customers seeking differentiated products beyond commodity opal glassware.
