In extrusion blow moulding of household chemical containers from TPC (Japan) HDPE KL160C, the resin is processed on a shuttle blow moulder with a single-screw extruder of 24:1 to 30:1 L/D and a barrier screw fitted with a Maddock mixing section. The die-exit melt temperature is controlled in the range of 180 °C to 210 °C, while the die gap is set from 1.2 mm to 2.5 mm for 500 mL to 2 L containers. A high-density polyethylene carrier masterbatch is let down at 2.0 wt% to 3.0 wt% for white or blue opacification; loadings above 3.5 wt% can increase melt-pressure variation and reduce pinch-off weld integrity. In-house regrind is commonly introduced at 15 wt% to 25 wt%, provided the flake is dedusted and shown by ash testing to be free of silicone-based mould releases; regrind above 25 wt% tends to reduce environmental stress crack resistance below the threshold required for bleach-containing formulations. The mould circuit is held at 10 °C to 20 °C with chilled water, and blow air pressure is maintained between 0.6 MPa and 0.9 MPa. Screw speed is adjusted to keep die-head pressure from 20 MPa to 30 MPa; excessive back pressure raises melt temperature and accelerates oxidative yellowing. Leak testing uses pressure decay at 35 kPa for 5 s on every cavity. ESCR is evaluated according to ASTM D1693-15 Condition A in 10 vol% Igepal CO-630 at 50 °C; a minimum F50 of 200 h is typically specified by household chemical formulators for detergent and sodium hypochlorite bottles. The terminal product is a 1 L cylindrical bottle with a nominal sidewall thickness of 0.7 mm, a 28 mm HDPE screw neck, and a polypropylene cap with ethylene-vinyl acetate liner. Compatibility testing with the filled product is conducted at 40 °C for 21 days; rejection criteria include stress whitening, delamination, leakage, and cap torque loss greater than 0.5 N·m. Grade-specific published data for KL160C on this exact bottle geometry is limited; therefore, every new tool should be validated with the intended fill and closure type.

What governs drop impact retention in cosmetic and personal care bottles?

For 100 mL to 500 mL cosmetic and personal care bottles, KL160C is processed on shuttle or reciprocating-screw blow moulders with mould temperatures of 12 °C to 18 °C and cycle times of 14 s to 18 s per single-cavity station. Wall thickness distribution is measured with a Hall effect thickness gauge using a 3 mm target ball; typical targets are 0.4 mm to 0.8 mm in the sidewall, 0.5 mm to 0.9 mm in the shoulder, and 0.8 mm to 1.2 mm at the pinch-off. Regrind from tails and trimmings is incorporated at up to 20 wt% when the regrind is stored in closed containers and checked for gel specks using a 100 µm screen changer; higher regrind loadings degrade drop impact retention at -20 °C and increase surface haze in gloss-critical packaging. Drop impact performance is assessed by ASTM D2463-15 at 1.2 m after conditioning at -20 °C for 24 h; filled bottles with surfactant-based lotions or shampoos are aged at 45 °C for 14 days before retesting because ester and ethoxylated components migrate into the polyethylene and shorten environmental stress crack resistance. Gloss retention is measured at 60° geometry under ASTM D523 on flat panels; a drop in gloss below the agreed quality index after regrind addition often indicates microgel formation. The terminal article is a 250 mL shampoo bottle with a 24/410 neck finish, a 0.55 mm minimum sidewall, and a flip-top polypropylene closure. Only external mould release agents that are volatile below 120 °C and non-silicone are permitted, because silicone residues interfere with label adhesion and with hot-stamp decoration of the shoulder.

Accumulator-head extrusion blow moulding of 10 L to 25 L agricultural chemical jerricans from KL160C places the highest demand on parison sag control and weld-line integrity at the pinch-off. The accumulator head is sized with a shot capacity of 5 kg to 8 kg, and the mould clamp force is selected in the 400 kN to 600 kN range to maintain parting-line register during inflation. Melt temperature at the die exit is kept between 190 °C and 210 °C, and the die gap is opened from 2.5 mm to 4.0 mm to compensate for die swell and to prevent melt fracture on the large-diameter parison. Parison drop time is held below 3 s to avoid uneven wall thinning in the top and bottom chime areas. A carbon black or dark-green masterbatch is let down at 2.0 wt% to 3.0 wt%, and a hindered amine light stabilizer masterbatch is incorporated at 0.3 wt% to 0.8 wt% when the jerrican must withstand prolonged outdoor storage. Post-consumer recyclate is not used in safety-critical UN packagings unless specifically qualified on the finished article with drop and stack tests; post-industrial regrind of the same grade may be used up to 15 wt% after melt-flow ratio monitoring under ISO 1133-1:2022. Hydraulic pressure testing is performed at 100 kPa internal pressure for 30 min according to the UN 6.1.5 sequence for Type 3H1/Y. Drop testing is carried out from 1.2 m after conditioning at -18 °C for 24 h with the jerrican filled to 98% nominal capacity with water; stack load testing applies a top load of 100 kg at 40 °C for 28 days. The terminal product is a 20 L rectangular jerrican with UN marking formatted as UN 3H1/Y, followed by relative density, hydraulic test pressure, and approval country code. Because published data for this specific configuration is limited, lot qualification must be repeated after any change in regrind content, color masterbatch, or closure gasket material.

Dairy and Juice Bottle Compliance Under Cold-Fill and High-Acid Conditions

Monolayer dairy and juice bottles made from KL160C are produced on extrusion blow moulding wheels with 10 to 20 stations; the melt temperature is maintained at 185 °C to 205 °C at the die head, and the die gap is set between 1.2 mm and 2.0 mm. A titanium dioxide masterbatch is let down at 2.0 wt% to 4.0 wt% for light-shielding and whiteness; the carrier resin must be a high-density polyethylene with a melt flow rate within ±0.2 g/10 min of KL160C to prevent local viscosity striations. Regrind from start-up and tail flash is added at 10 wt% to 20 wt% only after verification that the regrind does not raise the overall migration of the finished article. Food-contact compliance is evaluated under FDA 21 CFR § 177.1520 and EU No 10/2011; the finished container is tested for overall migration using food simulants assigned under EU No 10/2011 with a limit of 10 mg/dm². For pasteurized milk at 4 °C, the sidewall thickness is generally specified at 0.35 mm to 0.55 mm for a 1 L bottle, and top-load resistance is measured by ASTM D2659-16 with a minimum of 250 N after conditioning at 25 °C and 50% RH for 48 h. Monolayer KL160C is not recommended for hot-fill juice above 60 °C, because the softening range of the material leads to panel distortion and cap seal loosening; for high-temperature filling, a multilayer polypropylene structure or a modified vacuum panel design is used instead. The terminal product is a 1 L milk bottle with a 38 mm tamper-evident screw cap, a pinch-off flash thickness no greater than 1.0 mm, and a closure leak test at 35 kPa for 5 s.

When multilayer coextrusion is required for oxygen-sensitive sauces and mayonnaise

In multilayer extrusion blow moulding for oxygen-sensitive sauces, mayonnaise, and ketchup, KL160C is used as the outer and inner structural layers because it provides moisture resistance, stiffness, and high melt strength in the parison. The layer structure consists of KL160C/tie/EVOH/tie/KL160C, with KL160C comprising 70 wt% to 80 wt% of the total wall thickness; the EVOH layer is typically an ethylene-vinyl alcohol copolymer containing 32 mol% ethylene, and the tie layers are maleic anhydride-grafted polyethylene. The coextrusion blow moulder is equipped with 5 or 6 extruders and a spiral mandrel die; the KL160C melt temperature is held at 200 °C to 215 °C, while EVOH is processed at 190 °C to 205 °C and the tie resin at 195 °C to 210 °C. EVOH must be dried to less than 0.05 wt% moisture before extrusion; insufficient drying causes splay, microbubbles, and interlayer delamination at the parison seam. Die gap is set from 1.8 mm to 2.5 mm, and blow air pressure is 0.7 MPa to 1.0 MPa. Oxygen transmission rate is tested under ASTM D3985 at 23 °C and 50% RH; a target package oxygen permeance of 0.1 cm³/(m²·day·atm) to 0.5 cm³/(m²·day·atm) is common for shelf-stable sauce bottles, but the final value depends on EVOH layer thickness and humid storage conditions. The terminal packaging is a 500 g squeezable sauce bottle with a 0.8 mm total sidewall thickness, a 28 mm neck finish, and a multilayer structure that retains at least 90% of its original oxygen barrier after 30 days at 30 °C and 80% RH. Processing boundaries include a maximum melt temperature of 230 °C for KL160C; above this value, molecular weight degradation increases melt flow variation and can shift parison hang time, leading to uneven wall thickness distribution.

For pharmaceutical and nutraceutical containers, KL160C is extrusion blow moulded into 30 mL to 250 mL bottles on 6-station wheels or shuttle machines with melt temperatures of 180 °C to 200 °C and die gaps of 1.0 mm to 1.8 mm. A white pigment masterbatch containing titanium dioxide is added at 2.0 wt% to 3.0 wt% for opacity and light protection; the masterbatch must not contain slip additives that can migrate into the dosage form. Because the resin is not pre-dried under normal indoor humidity, pre-drying at 80 °C for 2 h is applied only when silo storage has exposed pellets to relative humidity above 60%, since surface moisture can produce splay in the neck finish. The finished container is evaluated under USP <661.1> for plastic packaging systems; the physicochemical test panel includes nonvolatile residue, heavy metals, and organic volatile impurities as defined in the current monograph. Where the bottle is intended for veterinary or international markets, compliance with Ph. Eur. 3.1.3 or Ph. Eur. 3.1.5 is assessed on the finished article. The terminal product is a 60 mL white HDPE bottle with a 0.7 mm minimum sidewall, a 33 mm child-resistant polypropylene closure, and a heat-sealed induction liner. In-process controls include a leak test at 30 kPa for 5 s, a neck dimension check by plug gauge, and a cap torque test with a rejection limit below 1.5 N·m removal torque after 24 h of capping. Published data for KL160C in pharmaceutical container applications is limited; packaging qualification must be repeated for each drug product because the formulation controls extractables and closure compatibility.

Automotive washer reservoirs demand low-temperature impact performance after vibration welding

Blow moulded automotive windscreen washer reservoirs manufactured from KL160C are produced on accumulator-head machines with shot capacities of 2 kg to 5 kg and mould clamp forces of 300 kN to 500 kN. Melt temperature at the die exit is set from 190 °C to 210 °C, and the die gap is held at 2.0 mm to 3.5 mm to maintain a uniform parison for complex asymmetric parts. A black or grey masterbatch is added at 2.0 wt%; carbon black masterbatch from the same high-density polyethylene carrier is preferred because incompatible carriers lower weld line strength at the mounting boss. Post-industrial regrind is used up to 15 wt% after density and melt-flow testing per ISO 1183-1 and ISO 1133-1:2022. The reservoir must withstand vibration welding or hot-plate welding of injection moulded spigots and brackets; welding is performed at 210 °C to 230 °C on the hot-plate surface with a weld displacement of 1.0 mm. Vibration welding equipment is operated at 200 Hz to 240 Hz with an amplitude of 1.0 mm to 2.0 mm; insufficient weld displacement leaves channels that leak at the boss, while excessive displacement produces weld bead flash that can obstruct the level sensor port. After welding, the assembly is pressure-tested at 70 kPa for 30 s and leak-tested under water at 10 kPa air pressure. Low-temperature impact is evaluated by ISO 179-1:2010 Charpy notched specimens at -40 °C; tensile yield stress and elongation at yield are measured under ASTM D638-14. The terminal product is a 3 L windscreen washer reservoir with integrated pump port and level sensor fitting; continuous exposure to ethylene glycol washer fluid is tolerated at service temperatures up to 80 °C, but prolonged operation above this temperature, especially with concentrated coolant, may soften the reservoir and distort the seal face. KL160C is not recommended for direct contact with brake fluid or hot engine coolant, because these fluids either swell the polyethylene or exceed the heat deflection temperature of the polymer.