For a face moisturiser, glass or PP may hold the cream directly; acrylic (PMMA) may not — oils and alcohol craze and cloud it, so every acrylic jar is specified with a PP inner cup, and an acrylic jar quoted "without liner" is a quote for a different product. Glass is inert with the best barrier at 2–3× the weight of plastic; PP is the standard for acids and oils and the cheapest route; acrylic gives the thick-wall, glass-look shell. Stock glass and PP both start at about 500 pieces, printed at about 2,000; glass runs 30–60 days, PP 7–25 days. Whatever the material, confirm it with the actual cream at 48°C for 30 days.
The three materials in one table
The choice is decided by what the cream does to the wall, what the wall does to the cream, and what the jar has to weigh and cost.
| Property | Glass | PP (polypropylene) | Acrylic (PMMA) shell + PP cup |
|---|---|---|---|
| Bulk contact | Yes — inert; best barrier | Yes — chemically robust; standard for acids and oils | Never — PMMA must not touch the bulk; PP cup mandatory |
| Clarity and look | High-flint clear, opal, amber; press-formed; heavy premium | Hazy unless clarified grade; usually opaque or translucent | Highest clarity and gloss; thick-wall, weighted, glass-look |
| Weight | 2–3× plastic; 50 ml thick-wall ≈150–220 g (typical partner-factory range) | Lightest; low resin and freight cost | Shells specified at 10–45 g; heavier shells cost more resin and freight |
| Weak points | Breakage, thermal shock, decoration cost; annealing tested to GB 4545 | Clarity; low-temperature brittleness in some grades; poor UV without additive | Stress-cracking from alcohols and oils; poor drop performance; two components |
| Formulas it suits | Face and night cream, balms, oil-rich masks, AHA/BHA, essential-oil formulas | Face cream, acids (pH below 4), oils, gels, clay masks, body butters | Any cream — inside the PP cup; fill below the brim |
| Decoration | Screen ≈USD 0.014/colour; spray ≈USD 0.07–0.15; frosting | Screen, spray after flame treatment, in-mould label, moulded-in colour | Spray, vacuum metallising on the shell; plated or metallised lids exterior only |
| Stock MOQ (indicative) | About 500 undecorated; 2,000 printed; 2,000–5,000 sprayed per shape | About 500; 2,000 printed; 5,000–10,000 moulded-in colour | 500–3,000 stock double-wall; 2,000–5,000 sprayed (typical partner-factory range) |
| Own shape | 30,000–200,000 made-to-order; ≈USD 555 per cavity | 3,000–10,000 + RMB 25,000–70,000 tool | 3,000–10,000 + tool; shell and cup are two tools |
| Factory-gate lead time | 7–10 in stock; 30–60 days for a furnace run | 7–10 in stock; 15–25 if a run is needed | 15–25 days stock; sprayed 30–40 |
Why PMMA needs a liner
Acrylic is polymethyl methacrylate. Its virtues are optical — the highest clarity and gloss of the cosmetic plastics, and it can be moulded thick enough to give a jar the weight of glass at a fraction of the freight. Its weakness is chemical. PMMA has poor solvent resistance: oils, essential oils and alcohol attack the surface and the stressed regions of the moulding, and the damage shows as crazing (a network of fine cracks), clouding and, on a double-wall jar, a milky bloom where the cream has crept into the gap. Handbook practice is blunt about it: an acrylic jar generally cannot hold the bulk directly, needs an inner cup as a barrier, and must not be filled so full that cream reaches the space between cup and shell.
So the rule in every specification is the same: PMMA is the outer shell only; a PP (or PE) inner cup carries the cream; the fill line sits below the brim. The cup is a separate injection-moulded part with its own minimum, and it is the reason a lined 50 ml acrylic jar holds noticeably less than its outer size suggests — see why a 50 ml jar holds less than 50 ml. When a supplier quotes an acrylic jar "without liner" to hit a price, the cheaper number is for a jar that will fail the 48°C / 30-day test with any oil-rich or alcohol-bearing cream.
Which material for which moisturiser
Viscosity, pH, ethanol content and oil load decide the material; the look is applied afterwards by decoration.
| Formula | Jar rule | Why |
|---|---|---|
| Face cream, night cream (emulsion 2,000–50,000 mPa·s) | Glass or PP jar with inner lid, foil seal and spatula; acrylic only with a PP cup; airless if it carries retinol or peptides | Jars give the best shelf presence and the worst hygiene after opening; the inner lid and seal are not optional |
| Vitamin C, retinol, peptide creams | Airless preferred; otherwise opaque glass or PP with foil seal and opaque carton | Oxygen and light cause browning and potency loss |
| AHA/BHA, pH below 4 | Glass or PP; no plated or metal part in the bulk path | Acid etches coatings and plating |
| Balms, body butters, oil-rich masks, essential-oil formulas | Glass or PP; never AS or unlined PMMA | Oils craze PMMA, attack AS and extract plasticisers |
| Gel and sleeping masks (may contain alcohol) | PP, PS clear or glass with a sealing inner lid | Alcohol crazes PMMA; gel dries unless the inner lid seals |
| Clay masks, cleansing powders | PP or glass wide-mouth Ø63–Ø89 with moisture-tight disc liner | Moisture ingress cakes the product |
| Any acrylic jar | PP inner cup always; fill below the brim | PMMA must not touch the bulk; bulk between cup and shell causes crazing |
| Plated or metallised lid | Exterior only; inner lid in PP or PE | Nickel is a contact allergen; plating never contacts bulk or skin |
The eight material rules behind this table, including the ethanol-above-30% and pH-below-4 rules, are on the formula × packaging compatibility matrix.
Weight, freight and the premium feel
Glass earns its place when the story is inertness and heft and the price supports the freight: a thick-wall 50 ml glass jar in the typical partner-factory range weighs 150–220 g against tens of grams for PP, and empty packaging ships as volume and weight. Acrylic's proposition is that a 30–40 g shell delivers most of that thick-wall feel, survives a parcel better and costs less to move; the price is the second component and the liner rule. PP is the honest choice when the cream is the hero: cheapest, chemically robust, coloured through the material at 5,000–10,000, and the standard for acid and oil formulas.
What to test before you commit
- Compatibility: the actual cream in the PP cup or glass at 48°C for 30 days, with ambient and cold controls — no discolouration, odour, swelling, crazing of an acrylic shell or decoration attack.
- Seal: jar 3/4 filled with dyed water, inner lid fitted, lying and inverted at −0.06 MPa for 5 minutes with no dye outside the seal area; 24 h inverted static test.
- Torque: opening 0.2–0.7 N·m on standard screw caps, reverse ≥2.5 N·m without thread strip, measured on 20 samples.
- Thermal cycling and drop: filled, +50°C 24 h and −10 to −15°C 24 h with no cracking or leakage; 1.5 m drop at 45° onto concrete with closure — the test acrylic and AS are most likely to fail.
- Glass specifics: annealing checked on a polariscope (GB 4545); stones over 1 mm rejected, none on the sealing land; thermal shock to GB/T 4547.
The four inspection gates and the full battery are on the QC standards page; the thirteen finishes and what each does to a jar's minimum are on decoration process comparison. Minimums and days by route for all three materials are in cosmetic jar MOQ and lead time and the MOQ index. Before paying a deposit on any of them, read how to evaluate a China packaging supplier.
Vella is a Guangzhou-based beauty packaging solutions provider — a sourcing partner working with vetted partner factories operating to ISO 22716 / GMP — and writes the PP-cup rule, the brim-full tolerance and the seal and torque thresholds into the jar drawing before a quote is issued. The three materials are on cosmetic jars; a cream planned alongside a serum and an oil is on skincare packaging solutions.
Frequently asked
- Sunscreen Bottle Options: Tube, Airless, Pump Bottle and Stick — Sizes, SPF Compatibility and MOQ
- Toner Bottles: Glass vs PET, 100–200 ml Sizes, Flip-Top, Disc-Top and Spray Closures, MOQ
- Body Butter Containers: 100–500 ml Jars in PP, PET and Glass, Wide-Mouth Closures, MOQ and Lead Time
- Airless vs Tube for Sunscreen: Dose, UV Protection, Cost and MOQ
- HDPE vs PET for a Shampoo Bottle: Material, Neck Finish (24/410 vs 28/410) and Leak Test
Not sure which jar your cream needs?
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