“Note – blow molding process method” in the world comes from the early 1950 s.
Foreign polyolefin (HDPE, PP) the application of medicinal plastic bottles in the early seventy s.
The relevant equipment manufacturers have the American Wheaton, Jomar, German Battenfeld, Bekum, ASB, aoki solid of Japan, the Italian Uniloy Milacron company, main models for one-step sod, vertical screw structure is used in the United States, Japan, Germany, Italy, adopts horizontal screw structure.
Domestic first system to introduce “note -” assembly line and production of pharmaceutical packaging plastic containers have force pharmaceutical factory (1984), born in tianjin and Shanghai daming glass (1985).
Medicinal plastic bottles and for digestion, absorption, the comprehensive promotion of polyolefin in our country have done a lot of basic work.
Vader machinery co., LTD in jiangsu province since 1989, the first to develop “three points” one-step “note – blow moulding machine”, the first on the market in 1991, after 10 years of efforts, has made great progress.
With the development of pharmaceutical industry in our country and the support of the masses of users, the size of the 100 annual production in recent years high speed development, make Chinese pharmaceutical packaging container (especially solid medicine tablet, capsule packaging) has been greatly improve overall quality level.
Second, the commonly used medicinal plastic bottles production technology and material choice
1. The production process
(1) to “force” Extrusion Blow – Blow moulding, also known as hollow Extrusion Blow molding.
Continuous extrusion hollow tube extruder, with scissors (artificial) or cutting device (automatic) cut into small pieces back into crowded blowing moulds made type.
Advantages: simple equipment, small investment, low cost price.
Weakness: the bottle, seal is poor.
Raw materials are usually choose LDPE, resistance performance is far lower than the HDPE/PP, charging quality storage period is short.
(2) Two steps “note -” Two steps Injection, Blow moulding.
“Injection and blow molding” by independent separately from the two machines, commonly known as “two steps”.
Step one: by a normal injection molding machine injection molding pipe, tube billet bottle head part (bottle, thread) has been forming;
The second step: artificial or automatic cycle heating tube billet in honeycomb heaters heating temperature on the conveyor belt, and then moved to the bottle blowing machine made type compressed air blowing.
Advantage: the equipment is simple, less investment.
The bottle is smooth, good seal.
Variety development faster, mould cost is low, cost and low price.
Disadvantages: injection tube billet and blow molding for step by step, easy transfer pollution, bacteria difficult to guarantee, the product identity is poor, not too used to mass production.
(3) the one-step “note -” One step Injection – Blow moulding.
“Injection and blow molding” on the same machine.
According to the model is divided into three different location and two location “note – blow”.
Sod “note – blowing bottle blowing machine” three location at 120 ° Angle into an equilateral triangle distribution, the first station for injection molding station, the second location for blow molding station, the third station to take off the bottle location.
Three station can be run at the same time, high efficiency, short cycle, and can be connected to the conveyor belt, automatic counting packaging, really realizes the medicinal plastic bottles in the whole process of production and people “no contact”, to ensure product sanitation clean.
Two location “note -” plastic machine two location can be arranged before and after, under, or;
First station for the injection molding station, the second location for blow molding station;
Due to less a dedicated to take off the bottle and cooling, so difficult to realize automatic counting packaging (generally for bulk artificial count).
In addition, a longer production cycle, production efficiency is lower than 3 Labour.
Advantages: a high degree of automation, high production capacity.
Bottle high flatness, excellent sealing.
HDPE/PP raw materials, the bottle wall even, resistance and excellent performance, charge and long storage period.
At present, the domestic standardization of drug package enterprises basically using one-step process equipment “injection”, which is given priority to with “three points” structure.
Weakness: the equipment investment is large, complex mold, high system configuration requirements.
Don’t adapt to small variety, small batch production.
But mass production can obtain high quality and low costs, better economic benefit.
2. The commonly used plastic raw materials
Solid drug packaging appropriate chooses HDPE/PP, one-step “note -” process production of polyolefin plastic containers;
Liquid filling drug appropriate chooses PET/PP “note – pull -” process in the production of plastic containers.
(3) the colorant and processing AIDS
Bottle stain usually choose titanium dioxide TiO2 (sharp titanium type or rutile type), the content of TiO2 98% Wt or higher, adding amount of 1.0 1.5% Wt.
Commonly used processing AIDS zinc stearate lubricants, polyethylene wax.
All is white powder, adding 0.1 1% Wt.
In recent years, to meet the requirements of GMP and thousand grade purification, general will TiO2, zinc stearate, polyethylene wax and LDPE (high m. I) mixed together into a concentrated masterbatch, can greatly reduce the dust pollution during the production.
A typical TiO2 pigment of formula is as follows:
TiO2 (super) 60%
8% zinc stearate
10% of polyethylene wax
For solid drug packaging HDPE, PP is more suitable material, has excellent resistance to water vapor permeability, can effectively prevent moisture absorption metamorphism.
But for the oxidation of drug should be used carefully.
LDPE oxygen resistance performance is poor, should not be production of medicinal plastic bottles, more can’t filling storage period longer.
PET are excellent resistance to water and oxygen permeability, and transparent appearance, is filling the liquid drug (syrup, oral liquid) ideal choice.
Three, medicinal plastic containers “note – blow molding equipment and mold
Early structure include: injection mold (mould), blow molding mould (forming dies), group (three) of rods, hot runner, nozzle, take off the bottle of card board, mandrel several major components.
Advanced materials, thermal expansion coefficient, surface finish, machining process and precision, design and debugging experience, especially the injection mold temperature control are impact on final bottle product quality.
Fourth, system design
System design and form a complete set of device for “note -” line should be attached great importance to the influence of efficiency.
Medicinal plastic bottles production enterprises in addition to choose reliable performance “note – blow molding machine and quality precision” note – blowing mould, must to the appropriate GMP system design plan and process flow, main content includes:
1. The central air conditioning system (GMP standard factory building, hundreds of purification, GB/T 16292-16294-16294)
Key indicators: thousands of cleanliness level, level 3 filters (fine, medium, high), top side back to the way.
Ventilation rate 20 times/hr 〓 or higher temperature T = 26 to 28 ℃
2. The chilled water system
Temperature T = 5 °, 15 °, pressure P acuity 0.2 Mpa, flow rate Q rating or higher
3. The cooling water system
Temperature T 28 ° or less, pressure P acuity 0.2 Mpa, flow rate Q rating or higher
Spray, circulatory system
4. The compressed air system
P p 1.0 Mpa pressure, flow rate Q p calibration values, configure buffer tank, freeze dryer, secondary filter (40 mu, mu) 5, automatic drain valve, compressed air temperature of 65 ° < 20 ℃.
5. Mould temperature controller
Water medium mould machine: work Tmax acuity a temperature of 120 ℃, and the P P 0.4 Mpa, the microprocessor or PID control.
Operating temperature of the oil medium mould machine: Tmax = 30-300 ℃, P P 0.2 Mpa, PID control instrument or a bit type.
6. Mixing, feeding, crushing device
Controllable (timer), mixing time is too long too short cannot achieve the best effect of mixing.
The top charging way recommended, may also adopt automatic vacuum material feeding material, but should choose concentrated masterbatch coloring, prevent dust pollution levels from the workshop.
Mill should choose low noise, high efficiency of the rotating cutter (mainly crushing cap injection flow rack and a small amount of waste bottle), is expected to add back amount should be reasonable fit for less than 15% (wt), to prevent repeated cyclic degradation affect performance.
Different type of raw materials back to the material must be handled separately (general bottle resin m. 1.0 or less, I cover with resin m. I > 5), can not be used randomly.
Five, the discussion
Medicinal plastic bottles production according to its specific performance, should be:
1. Choose “note -” process to make sure that the bottle smoothness, high density, sealing good permeability, thus ensuring charge stability, prolong the storage life.
2. Choose one-step sod “note – blow molding machine and precision mould, to ensure that the product precision so as to achieve high quality, high yield and high efficiency, low cost, quick return of investment.
3. The system design (GMP, technological process, chilled water system, cooling water system, compressed air refrigeration purification system, electrical system, auxiliary engine) is a very important link, is also charge a necessary condition for stable production and the development of an enterprise.