DE2062283A1 - Biaxially oriented article and a method and an apparatus for its manufacture - Google Patents

Description

EGG. du Pont de Nemours and Company Wilmington, Delaware / USA

Biaxially oriented article and method and apparatus for its manufacture

The present invention relates to a hollow, biaxially oriented thermoplastic article, such as a bottle, which is particularly suitable for filling liquids under pressure, such as carbonated beverages or aerosols, etc., together with a method and an apparatus for its manufacture. ■ ■. ■■ "..-.. Thermoplastic bottles suitable for filling carbonated beverages, which are under a certain autogenous pressure during filling, must have the properties required for such use. These properties consist in the strength required to keep the beverage under pressure which can carry 7.03 atmospheres without a noticeable change or serious deformation occurring within the temperature range of about 0-5 ° C used. In addition, the bottle must have low permeability, especially with regard to carbon dioxide and oxygen. The constant loss of carbon dioxide from carbonated beverages or the ingress of oxygen into a beverage such as beer

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shortens the lifespan and changes the taste of the drink.

Several methods are known to produce hollow thermoplastic articles to manufacture. One method is blow molding. In conventional blow molding, a parison is first produced by a heat softened thermoplastic tube is extruded and the bottom pinched off, or it becomes a blowable geometric one Direct injection molded form. Next, the parison or the blown mold is then placed in a mold cavity with the volumetric Formed the desired thermoplastic object and expanded the parcel by pushing it in with compressed air the edges of the mold cavity is blown. The polymer is extruded and blown at an elevated temperature, namely above the biaxial orientation range of the polymer. The molded body produced is not biaxially unoriented. This The process is economical but relatively slow and, most importantly, the hollow objects produced leave the lack the necessary strength to be used for filling beverages under pressure.

Other previously known methods consist in the use of solid plastic blanks which are extruded to form a hollow object. When a solid blank is extruded shows the material that was originally on the outer axis of symmetry of the blank, on the inner wall of the manufactured Extreme roughness and other surface damage. The use of higher temperatures during the production of the article leads to the fact that these are undesirable Properties are reduced, but the use of higher temperatures leads to self-destruction, since the the biaxial orientation. the strength of the plastic material possibly gained during bottle manufacture Heat relaxation is lost again.

There is therefore a need for an economical process at. a device for the production of a plastic bottle with properties that make it suitable for filling liquids under pressure, such as carbonated beverages and a'rosols, makes it suitable.

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The present invention resides in a method and apparatus for making a hollow, biaxially oriented thermoplastic article having improved strength properties. The article is biaxially oriented by ^{stretching it an average of about 1} 1/2 times in the axial direction and about 2.5 to 7 times in the circumferential direction. The preferred thermoplastic material used is polyethylene terephthalate with an inherent viscosity of at least 0.55. The manufactured article not only has improved strength properties, but also a reduced permeability to carbon dioxide, oxygen and water. As a result, the method and apparatus is particular for the manufacture of thermoplastic J bottles used for filling beverages under pressure, such as carbonated fizzy drinks and beer. Polyethylene terephthalate bottles produced by the process according to the invention have a density of about 1.331 to 1.402 and the straight cylinder cross-section of the bottle has an axial tensile strength of about 351 * 54 to

2119.24 kg / cm ² , a circumferential tensile strength of etvra 1406.2 to

2
5824.8 kg / cm; an axial yield stress of at least 281 kg

2 2

/ cm and a circumferential yield stress of at least 492.1 kg / cm. For these bottles, a Plant el thickness of about 0.2539 to 0.762 mm, a weight-to-volume ratio (in g or cm-) of about 0.2: 1 to 0.005: 1 and a deformation constant that * Equal to the curve of the logarithm (reciprocal value of the rate of elongation) plotted against elongation with a value of at least 0.65, typical. The method is expediently carried out with the aid of a used mold in order to obtain uniform and matching copies of the object. The hollow thermoplastic blank is extruded through an annular passage opening into a sliding mold, the mold having a bead-like recess at one end to receive the extruded product; the mold is then allowed to slide through the extrusion port while the extrusion is continuously continued. The extruded product is thereby stretched as it slides. At the same time, the extruded product is pressed against the inner walls of the mold.

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putting a liquid under pressure, inside the molded Object is introduced.

The device according to the invention, which is used for the implementation of ßi-inventive method is used, consists essentially the end: '

(a) a slidable mold with a cavity that has a shape has to get the item you want;

(b) an annular extrusion passage opening in the Mold cavity is arranged;

(c) means for extruding a hollow thermoplastic blank through the annular extrusion passage opening i-n the shape;

(d) Means in the form »to accommodate the extruded product, and forming and holding an annular bead of the extrusion at one end of the mold cavity;

(e) means for sliding the mold from a first position into a second position relative to the extrusion passage opening while the thermoplastic blank is continuous is extruded and drawn into the interior of the mold to form a hollow shell from the extrusion;

(f) means for introducing a liquid against the interior of the hollow shell to compress the extrusion against the to expand the inner boundaries of the shape and if necessary

(g) means for urging the trailing edges of the extrusion radially inward towards the center of the article to form a complete seal.

Fig. 1 shows the perspective of the device according to the invention with means for driving the moving parts of the device. Fig. 2 is a schematic representation of the main parts of Fig Device of Fig. 1 and shows the hydraulics, the system for the fluid flow and the electrical system for driving and regulating the device.

Fig. 3 is a partial cross-section of the device according to the invention during the initial stage of forming a hollow counter-

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Standes and 'shows specifically an annular shaped bead. Figure 4 is a partial cross-sectional view of the apparatus of the present invention during the inter-fishing stage in the manufacture of a hollow article and specifically shows the critical stage of combined non-molten extrusion and expansion using internal forces of the flow fluid. Fig. 5 shows a partial cross-section of the device according to the invention at a stage where the hollow object is completely manufactured. Is ■ Figure 6 is an enlarged partial cross section of a portion of the apparatus in a position which is shown in Figure 5 and in clearer detail the area around the annular Strangpreßdurchtrittsöffnung almost at the end of the combined extrusion - '.''- ■ /'.. and the expansion process.

FIG. 7 shows an enlarged partial cross-section similar to that of FIG. 6, but revealing the area around the annular Extrusion passage after the completion of the manufacture of the hollow article. '

8 and 9 are partial cross-sections of the device according to the invention, which is adapted to process polymers with poor shape uniformity.

FIG. 10 is a device produced in the device of FIG 'Bottle.

Fig. 11 is a partial cross section of another embodiment which has a sliding central rod with a central rod in its' fully extended position.

Fig. 12 is a partial cross section of the other embodiment, which is shown in Fig. 11, with the central rod in the intermediate stage dos retraction relative to the intermediate position of the sliding form. ,.

Fig. 13 is a partial cross section of the other embodiment showing is shown in Fig. 11, 'with the center rod fully retracted, correspondingly relative to the end position of the sliding form. possess pQlyüthyleJvterephthalatartikel according to the invention, generally cylindrical in shape, as for the shape of Soda or beer bottles are typical, are biaxially oriented, have densities of about 1.331 to 1.402, and can be clear

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and glossy without haze, or they can be colored by adding a dye to the polymer. In addition, the articles have physical properties necessary for holding liquids under pressure. The physical properties consist of high tensile strength, high tensile stress, low deformation with a low weight-to-volume ratio, high impact resistance and good permeability properties. Polyethylene terephthalates useful in making the thermoplastic articles of the present invention are (a) polymers in which at least about 97 % of the polymer has repeating ethylene terephthalate units of the formula

■ C-

and the remainder consists of smaller amounts of ester-forming components
and·

(B) copolymers of ethylene terephthalate, in which up to about 10 mol # of the copolymer of monomer units of diethylene glycol, propane-1,3-diol, butane-1,4-diol, polytetramethylene glycol, Polyethylene glycol, polypropylene glycol, 1,4-hydroxymethylcyclohexane and the like and from monomer units of isophthalic acid, diphenic acid, naphthalene-1,4- or 2,6-dicarboxylic acid, Adipic, sebacic, decane-l, 10-dicarboxylic acid and the like. are constructed.

The specific limits with regard to the comonomer are determined by the glass transition temperature of the polymer. It has been found that - if the glass transition temperature extends below about 50 ^° C. - a copolymer with poor mechanical properties is formed. Accordingly, this corresponds to the addition of no more than about 10 yiol% of a comonomer. An exception here is, for example, the addition of diphenic acid, at which the glass transition temperature of the copolymer ^{remains above 50 °} C. and does not fall with the addition of more than 10 mol-1. Other examples will be apparent to those skilled in the art.

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In addition, the polyethylene terephthalate glycol may contain various additives which do not adversely affect the polymer when it is used. Such additives are stabilizers, such as antioxidants or agents which shield ultraviolet light, extrusion auxiliaries, additives which are intended to make the polymer more degradable and combustible, such as oxidation catalysts, and dyes or pigments. ■. ■ -..- '"The polyethylene terephthalate should have an inherent viscosity (1 Ji ige polymer concentration in a 37 * 5 or 62.5 wt ..- # igen solution of tetrachloroethane or phenol at 30 ⁰ C) of at least 0, -55 * in order to obtain the desired final properties in the molded article, and preferably the inherent viscosity is at least 0.7 in order to obtain an article with excellent toughness properties, ie impact resistance Solvent measured alone and the inherent viscosity is the same

'natural Lo _E arith _m us

where C is the concentration expressed in grams of polymer per 100 ml of solution.

Biaxially oriented items are useful and lead to * improve the physical properties such as ■ an improved tensile strength and yield stress. The biaxial orientation x ^ ill be performed by the thermoplastic material in the axial and circumferential direction stretched _r, v / hile the object viird manufactured * The object of the invention is stretched molecularly by average stretched up to about 4 times in the axial direction and about 2 , 5 "·" 7 times is stretched in the circumferential direction. Such a stretching is preferably carried out at the orientation temperature of the thermoplastic material, ie above the glass transition temperature and below the crystal melting point.

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The degree of molecular orientation can be determined by known methods to be determined. A method for determining molecular stretching is published in the Journal of Polymer Science, 47 (1960), Pp. 289-306 and in the Journal of Applied Polymer Science, 9 (1965), page 2661.

Biaxial stretching helps to achieve excellent strength properties. According to the invention Manufactured objects do not have the same degree of orientation at every point on the object, but have the areas that are less oriented have a thicker coat than the areas that are more oriented. This gives the object a relatively high overall strength. In the preparation of a bottle has the thinnest jacket thickness in the straight cylinder cross-section, but this cross-section is the strongest oriented. The straight cylinder cross-section of the bottle produced by stretching shows the typical tensile strength and yield stress have the following values:

An axial tensile strength of about 351.5-2109.2 kg / cm, one

Circumferential tensile strength of about 14O6.2 - 5824.8 kg / cm, an axially

2 Ie yield stress of at least 28l, 2 kg / cm and a circumferential

yield stress of at least 492.1 kg / cm. The fourth of tensile strength and the yield stress are determined according to ASTM D 882, entitled "Tensile Testing".

The density (in g per era) of the article can vary between about 1.331 and 1.402. The density is determined according to ASTM 1505, entitled "Tensity Gradient Technique". The density is a measure of the crystallinity and this density range includes a crystallinity range of about 0-60 % . This crystallinity in % is calculated according to the following equation:

Crystallinity in % - χ 100

where Ps = the density of the test sample (in g / cm) Pa = 1.333 (g / cm), the density of an amorphous film with a crystallinity of 0 %. and

Pc = 1.455 (g / cnr) those from the cell unit parameters calculated density is

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The manufactured objects themselves can have different crystallinities along the axial length of each object. In this case, if necessary, the object can -. heat cured to achieve uniform crystallinity in each object. Orientation and crystallinity contribute to certain properties, but under certain conditions they compete with each other. For example, an increasing orientation means an increased tensile strength, but the thermal stability of the object is reduced at the same time. To compensate for the latter, the bottle can be thermoset to increase the crystallinity of the bottle. . ·

The crystallinity is also important for the shielding properties especially for the permeability properties of the item. When filling carbonated beverages under pressure, such as soda or beer, for example it is important that the bottles have shielding properties, which are sufficient to keep the carbon dioxide and water in the drink to keep »and still contain impurities, such as oxygen, keep away.

It has been found that an increase in crystallinity decreases the ability of carbon dioxide, oxygen or water vapor to penetrate the bottle. The term "penetration" and the terms derived therefrom, which are used in this application, mean the ability of an agent such as carbon dioxide, oxygen or water vapor to penetrate or diffuse through the jacket of the article according to the invention _: -.

The degree of penetration that occurs during use the bottle occurs - depends on many factors, such as the total surface of the bottle, the ambient temperature, dom internal pressure of the bottle and the type and amount of in the liquid in the bottle ».

Mtmn. the crystallinity of the bottle is at least about 15 % (density about 1.3 ^ 8) and the bottle is used for filling soda or beer in a conventional manner when using

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Usual bottle sizes of consumption, ie of 186.6 g, 248.8 β, 311.0 G, 373.2 g or 497.6 g bottles, the penetration value in relation to the various penetrating agents concerned is sufficient to meet the commercial standard. For example, bottles containing up to about 497.6 g of soda or beer under an autogenous pressure of about 5.27 atmospheres at room temperature, ie at about 25 ° C, with a jacket thickness between 0.2539 - Ο, 7β2Ο mm lose and their weight-to-volume ratio (in g or cwr) is about Q.2: 1 to 0.005: 1, in 30 days no more than 15 % carbon dioxide, the oxygen that penetrates through the jacket into the liquid, is not more than 5 parts per 1000 parts in "30 days and the amount of water that the fluid loses _t is not more than 5 % in 90 days.

The carbon dioxide penetration is determined by placing a bottle under a carbon dioxide pressure of 5.27 atmospheres and the The bottle is closed with the usual closure means, the pressurized bottle is placed in a vacuum chamber, in which the vacuum is 1 mm of mercury and the possibility is given that the bottle in the chamber is in equilibrium is held, and then the pressure increase in the vacuum chamber is measured as a function of time. Alternatively the same pressurized bottle can be placed in a closed chamber with a stream of nitrogen flowing through the Bottle swept past. After the gas stream of a sodium hydroxide bath wash was subjected, the titration of the standardized sodium hydroxide shows the amount of carbon dioxide, which was picked up when the nitrogen stream flowed past. The amount of carbon dioxide, determined per unit of time, gives the speed the carbon dioxide penetration. The oxygen permeation is determined by using a bottle is filled with gas-free water, the bottle is closed by conventional means and the bottle is at room temperature and room pressure is stored and the oxygen content of the water in the bottle is periodically determined by known methods, i.e. by potentiometric titration with the silver electrode.

-XO-

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The water penetration is determined by bringing a desiccator filler into the interior of the dry bottle, sealing the bottle, storing the bottle at 37 ° C in an atmosphere with a constant relative humidity of 100 % and then periodically vrogening it, to determine the amount of water that has been absorbed by the desiccator filler. Alternatively, the bottle can be filled with water, placed under an autogenous pressure of 5 * 27 atm and sealed and then placed in an atmosphere with a relative humidity of about 15 % at 25 ° C and the water loss weighed periodically.

Another significant property which is important for the articles of the present invention to be used for filling pressurized liquids is that the bottle exhibits relatively little distortion, particularly in the case of thin-walled, light-weight articles. Deformation is the change in the structural dimensions of the object when it is subjected to stress and depends on many factors, such as the degree of stress, the type of polymer, the physical state of the polymer, the ambient temperature and the time, to which the bottle is subjected to stress. When looking at the deformation of a generally cylindrical bottle, the size and shape of the bottle are also important. Furthermore, if the autogenous pressure in the bottle increases with increasing temperature, the resistance to deformation must remain constant over a reasonable temperature range and use pressure range. In typical uses, such as for filling beer or soda, this temperature range is about 0 - 50 ⁰ C and the pressure range is about 0-7> O3 atmospheres. The degree of stress occurring in a bottle used to hold a pressurized liquid, such as a carbonated beverage, is directly proportional to the autogenous pressure in the bottle, the bottle diameter and inversely proportional to the wall thickness.
The stress can be given by the equations:

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Scope = Pr / t

A Axial = Pr / 2t
can be expressed, where

y \ is the stress,

P is the autogenous pressure

r 'is the radius of the straight cylinder cross-section and t is the jacket thickness.

A bottle with. a diameter of about 5> O8 cm with a Wall thickness of the straight cylinder of about 5.058 mm at room temperature and which is under a pressure of about 5 »27 atmospheres and which withstands a hoop stress of about 0.228 atmospheres is typical. Thin-walled bottles are desirable because which means using less polymer and because these bottles are cheaper to manufacture. However, ' thin walls are more stressed and make a greater sense of * Resistance to deformation required. Biaxial orientation of a polymer increases - if the other factors remain the same Flow stress of the bottle and is therefore an important reason for orientation.

The deformation is generally determined on polymers by placing a sample under a fixed load, i.e. stress, is exposed at a constant temperature and the deformation is determined as a function of time. The curves for thermoplastic Plastics have a characteristic shape in which the rate of deformation is a function of time. When the logarithm (reciprocal value of the deformation speed) is plotted against the deformation, a linear one results Course of the curve over a substantial part of the deformation curve. The curve of the rectilinear segment, here as the deformation constant is expressed as:

DC = d lop; (dt / df)

where DC is the deformation constant,

dt = 'the derivative according to time and d £ = the derivative according to deformation.

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The deformation constant is applicable to the thermoplastics mentioned Plastics and can be used to reduce the deformation behavior by comparing the curve values. A deformation constant equal to 0 shows that the examined sample expands at its natural rate of deformation or that for the load determined the deformation speed remains constant. An infinite deformation constant shows that there is no measurable deformation is.

For the bottles produced according to the invention, the deformation constant is at least about 0.65 _9, which means a deformation of less than 5 % in 100 hours at 50 ^° C. and an autogenous pressure of 5.27 atmospheres. Yet another property of the biaxially oriented polyethylene terephthalate articles of the invention is toughness or impact resistance. However, this is particularly related to the inherent viscosity of the polyethylene terephthalate. In general, the greater the inherent viscosity, the greater the impact resistance of the bottle. This is demonstrated by a drop test in which a bottle is filled and sealed under typical filling conditions under an autogenous pressure of 4.21 atmospheres.

The bottle is dropped on a concrete floor so that the point of impact is on the edge of the base. In testing the bottles made in a similar manner but having different inherent viscosities, it has been found that if dropped at 0 ^° C. '

(a) Bottles with an inherent viscosity of 0.85 on average survive a fall from a height of 1.33 m, but fail, i.e., break if dropped from a height of 2.44 m;

(b) Bottles with an inherent viscosity of 0.95 on average Survive 2 falls from a height of 2.44 m, but fail in the third fall and

(c) Bottles with an inherent viscosity of 1.1 five cases protruding from a height of 2.44 m.

The one used to make the articles of the invention The device will now be described in detail with reference to the drawings. Referring to Figures 3-5, a below is made

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described hollow, cylindrically shaped thermoplastic polymeric blank 1 initially arranged in an extrusion chamber 2, which is formed by a bore of an extrusion cylinder 3 and the outer cylindrical surface of a central support rod k . A mold cavity 5 of a mold 6 has the interior design corresponding to the shape of the desired object and is arranged in a first position in which it encloses the extrusion cylinder 3, as shown particularly in FIGS. The mold cavity shown in FIG. 3 is used for the production of a narrow-necked bottle such as is used for filling carbonated beverages. The extrusion cylinder 3 is located in axial alignment on a mandrel 7 with a uniform outer diameter which is essentially the same as the inner diameter of the bottle neck of the bottle to be produced. A passage 8 for liquids is contained in the mandrel 7 and has liquid outlet openings at the end of the mandrel 7 which is in close proximity to the extrusion cylinder 3. An annular extrusion outlet opening 11 is located between the end of the cylinder 3 and the end of the mandrel 7. The annular extrusion outlet opening 11, which is shown in detail in FIGS. 6 and 7, is formed by the opposite end portions of the extrusion cylinder 3 and the mandrel 7. In the cross-sectional profile, both parts are worked into a curved shape to form a smooth transition from the annular extrusion chamber 2 to the outside and a boundary for the annular extrusion outlet opening 11 so that the cross-sectional area of this outlet opening is always convergent. _{The opening gradually becomes smaller 4} in the direction of the outflow towards the outer boundary of the extrusion ring, which is located in the vicinity of the circumference of the mandrel 7, from where the polymer emerges from the annular extrusion passage opening 11 in order to penetrate into the cavity 5 of the mold 6. In Fig. 6

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the axially measured dimension of the opening 11 is denoted by T. In this figure, as in FIG. 7, this dimension is enlarged for the purpose of clearer description. In an actual device, the dimension ¹¹ T "are depending on the properties of the forming polymer and, depending on the degree of the polymer to be imparted orientation between about 0.25 ¹ J and 1.905 mm. The outlet opening 11 serves as that point at which is supplied with high energy to the polymer, by which the temperature of the polymer is raised to the orientation temperature of the polymer, thereby ensuring good orientation properties. In general, the degree of orientation of the extrusion increases as the ratio between the average diameter of the extrusion and the average diameter of the blank increases when it emerges from the passage opening 11. ·

The annular extrusion passage opening 11 is - in cross section seen - surface convergent to provide a stable flow and a limited pressure drop between the chamber "2 and the To ensure outer part of the outlet opening 11 during the extrusion and in particular at the time in which the Initiation of closure of the end of the bottle-shaped article; In other words, a high pressure ensures in chamber 2 at the moment in. .dem the rod 4 is withdrawn is that the polymer flows from the chamber 2 inward (under the continued pressure of the plunger 15), thereby causing a seal.

The - mold cavity 5 has an annular groove I ^ in its unifangsform initially in the vicinity of the outlet side of the annular extrusion passage opening 11 is arranged. The mold 6 with its mold cavity 5 can also be different from the first shown in FIG Position are moved into a second position shown in FIG.

- «i

As shown in FIGS. 1 and 2, the means for moving the various parts of the apparatus essentially comprise hydraulic cylinders or hydraulic motors mounted on a frame 25 . The extrusion cylinder 3 is through

- 15 - '
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a splash is attached to a horizontal frame part 26 and aligned concentrically with the hollow extrusion die 15, which acts through an opening in the frame part 26 (not shown). Under the frame part 26, the ram 15 is aligned with a hollow, tubular piston rod 28 of a hydraulic motor 29 which has no transmission or can be extended from two sides and which is attached to the frame 25 and is connected to this piston rod. Inside the bore of the extrusion die 15 is the middle support rod 4, which. runs from the top of the extrusion cylinder 3 completely through the extrusion die 15 and the tubular piston rod 28. Below the lower end of the piston rod 28, the middle support rod 4 is connected to the piston rod of a further hydraulic motor 30, which is also attached to the frame 25. At the upper end of the frame 25 there is a dovetail-shaped slider 31 'whose body is attached to the frame part 26 and can be moved parallel to the axis of the cylinder 3. A boom 33 is connected to the slider 31 and carries the mandrel 7 in axial alignment on and at a distance from the extrusion cylinder 3. A rigid stripping fork J> k extends outward from the frame 25, the prongs of which straddle the mandrel 7 directly sit below the boom 33. The Dorn7 can be raised by means of the motor 32 in the vertical direction to ^1, the stripping of a molded container, not shown, to cause the mandrel. Furthermore, the extrusion chamber 2 is thereby exposed in the cylinder 3 to allow the introduction of a new plastic blank. The mandrel 7 and the extrusion cylinder 3 is surrounded by a multi-part mold 6 which has openings in its upper and lower ends, which are aligned in the axial direction with the two parts 7 and 3 and can slide along them. The mold 6 can be moved in the vertical direction using a hydraulic motor 35 ', the body of which is attached to the frame part 26. In FIGS. 1 and 2, the mold is shown in its lowest position in which it is at the start of the extrusion cycle. The mold 6 comprises two substantially symmetrical halves with a flat parting surface. The halves are comparable to each other by hinges

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■ tied as it is in Pig :. 1 shown, however, can also refer to. Slides or rods may be attached to allow the mold to be opened and closed on the extrusion cylinder 3 and mandrel 7. It should be noted that movable clamping means, not shown, must be provided to secure the halves of the mold together so that the mold can withstand internal pressures which reach substantial levels. Such clamping devices are known in the art and generally consist of bolts, pneunia tables or hydraulic motors, screw terminals or the like. It should also be noted that the walls of the mold can be provided with holes. The moldings may require heating or cooling, depending on the nature of the material of which the blank is made, and may be provided with individual jackets or passages, not shown, for electrical or fluid heating or cooling Require cooling and a jacket 36 is shown which encloses the part of the extrusion cylinder which is accessible below the mold 6. If necessary, the mandrel 7 can be equipped in a similar manner.

The hydraulic motors are controlled in chronological order by various magnetically operated valves and an electrical control circuit. As can be seen from FIG. 2, a gear pump 38 sends liquid under pressure from a sump 39 into several lines ¹ JO. The main hydraulic motor is the motor 29 which drives the ram 15 at a speed determined by the profile of a cam device 23 to be distributed in order to generate an output voltage corresponding to the position of the punch. This output voltage is supplied to a servo control-44, which in turn controls the ^ operation of the valve H3 by the speed of, the liquid stream sum motor 29 geändert.wird through the valve proportional to the output voltage _s in which the voltage and the current of the. Liquid gets higher, when the high

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Part 23b of the cam device; 23 is reached. The valve 41 is a self-centering four-way solenoid valve with ports that are blocked, as shown, when the electromagnets are not energized. When the electromagnet 42 a is energized, the valve rotates clockwise and lets the liquid into the opening 29 a of the motor 29, while at the same time the opening 29 b is connected to a drain line so that the liquid in the upper part of the motor 29 can return into the sump 39 via a line not shown. The supply of liquid into the opening 29a causes the upward movement of the plunger 28. When the opposing electromagnet 42b is excited, the valve 41 moves counterclockwise, whereby the plunger 28 is driven downward again. The arm 27 on the piston rod 28 also drives the movable part of a sliding resistor 24, which generates an output voltage which is proportional to the position of the rod 28 and the plunger 15 and which changes in size. This variable signal is used to control certain processes to be described. The system is activated by a drive control circuit 45 which supplies electrical energy from a power source 46 directly to the electromagnet 42 a on the valve 41 and at the same time a voltage comparison circuit 4?> Which also receives the input voltage from the slide resistor 24. The circuit 4? is able to generate 3 different output voltages in a chronological step sequence depending on the size of the output voltage of the sliding resistor 24, which depends on the position of the rod 28 of the motor 29. Thus, when the rod 28 and the punch 15 move, the following events occur one after the other:

1) The mold 6 is driven by the motor 35 via an electromagnet 50 a actuated valve 49 at constant speed set in motion upwards.

2) Shortly thereafter, pressurized liquid is passed through a solenoid valve 52 and a needle valve 53 to the mandrel 7, the passage 8 and the openings 9 and 10 with a controlled flow rate fed »

3) Near the end of the stroke of the punch 15, the mold stops at the end

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of the stroke of the cylinder 35 and the activity of the middle Support rod is closed by a signal from circuit 47 triggered an electromagnet 54 a. This creates a valve 55 causes to send under Druck.stand liquid into the upper opening 30 a of the motor 30, whereby the middle support rod 4 is pulled down. It should be noted that the stroke of the motor 30 is very short and between 2.5 * 1mm and 5.08mm. This motor and the rod 4 quickly reach the lower end in a downward direction and stay in this position.

When the rod 4 moves downwards, an approach actuates of the rod a limit switch LS / 1, causing a valve 56 in its open position is actuated * This will activate the needle ™ valve 53 bypassed and the liquid in the mandrel 7 * and the openings 9 and 10 at a greater speed than before let in. As an optional mode of operation of the motor 30 when the limit switch LS / 1 is closed, the electromagnet 5 ^ b can be energized via the switch 57. This will the valve 55 rotated clockwise, whereby liquid drained from the upper opening 30 a of the motor 30 and under pressure standing medium is fed to the lower opening 30 b of the motor Thus, in a very short period of time, the rod 4 pulled down, the switch LS / 1 actuated and the rod 4 pushed up again. "·

At the start of a cycle, or at any time after completion A of a cycle, the mold 6 can be opened and the mandrel withdrawn using the motor 32 in an upward direction. The valve 58 can be rotated by hand from the rest position shown into a position in which pressurized liquid is supplied to the opening 32b, whereby the motor 32 is driven and the mandrel 7 is moved upwards in order to effect a stripping process. At this stage, the mold 6 and the punch 15 are in their uppermost positions. They are withdrawn by final excitation of the current control circuit 45. As a result, the electromagnets 50 b and kz b are temporarily excited. , As a result of which valves 49 and 41 each rotate to, under pressure,

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to supply standing liquid to the upper ends of the motors 35 and 29, respectively and drive them down The electromagnets then de-energize so that the valves 49 and 41 are centered in their Can return to positions in which all openings are closed are. The extrusion chamber 2 in 'the extrusion cylinder 3 is again ready to receive a new blank, whereupon the mandrel 7 using the motor 32 and the valve 58 can be lowered.

Precision control of the moving parts of the apparatus according to the present invention is achieved electronically by the control means shown in FIG. For example, immediately after the formation of the bead in the annular groove 14, the mold 6 is set in motion at constant speed when the voltage comparison circuit 47 senses a preselected output voltage level at the slide resistor 24 when the punch 15 has a predetermined stroke of approximately 12.7-30 , Has traversed 48 mm. During the first part of the molding movement, the annular bead moves along the end of the mandrel 7 and over the mandrel 7, whereby the extruded material covers the openings 9 and 10. As the dome continues to move, the voltage comparison circuit 47 senses a different predetermined voltage level from the slide resistor 24, thereby triggering the operation of the valve 52 and releasing liquid in a predetermined amount. Amount is sent through the valve 53. As a result, part of the illegal part of the extrusion is expanded outwards against the molding surface in the annular space 21. With further movement of the extrusion die 15 and the mold 6, the neck part is completed and the diverging part of the mold cavity 5 begins to extend beyond the area in which the openings 9 and 10 are arranged, whereby newly pressed plastic can be expanded to a greater extent than in the neck portion as generally shown in FIG. At this stage, if the polymer reaches or breitesten part of the mold 6 to achieve begins, the punch 4 and the rod are advanced 28 to the point where the higher part 23 b cam device 23 moves the shift resistor 51 in a different position opened causing the valve 43 to a greater extent

- 20 -

109834/1023

F-2135/2135-R

if.

becomes »This will add a larger amount of fluid to the Motor 29 sent, which increases the extrusion rate of the polymer through the outlet opening II and more polymer Material for the outer viand of the one in the making Object delivers. .

As the punch 15 nears the end of its stroke, the slide resistor 51 returns once more to the lower level position on the cam device 23 so that the extrusion rate of the polymer through the outlet opening 11 is reduced; this happens essentially at the moment when the object is completed and the bottom is to be formed, and leads to a thinner bottom. Similar precision control is achieved just before the mold stops. The action of the middle support rod is triggered when the voltage comparison circuit 47 senses a certain voltage level from the sliding resistor 24. At this time, the electromagnet 54 a is excited and the valve 55 causes the supply of fluid to the opening 30 a of the motor 30. This begins to pull the rod 4 from its contact with the end of the mandrel 7 and actuates the limit switch LS -/1. This triggers the action of the solenoid valve 56, as a result of which the valve 53 is bypassed and pressurized flow fluid is sent into the cavity 16 at a greater speed than before. As a result, the expansion of the "extruded form" is terminated in a shorter time than if the valve 53 had continued to control the speed of the incoming flow fluid The effect of reversing the valve 55 would have _K so that a very short time after its retraction the rod 4 would have been pushed again towards the mandrel 7. The space previously occupied by the upper end of the rod 4 is then from Polymers! That bfi? § * is subjected to this process of a pushing action ia coordination with the pressure of the stamp 15 '* This operating step is preferred because the simultaneous effects result in a solid closure of high density

3ADC-L

to lead.

Another mode of operation is particularly suitable for polymers which, after being drawn or oriented, have poor conformability to a shape, particularly in the final stages of the formation of a container, in the present case the formation of the bottom of the container. This procedure essentially comprises the procedure described above with the additional step of reshaping the bottom of the container inwardly to form a concave recess. This is achieved by the device shown in Figure 1, in which the voltage comparison circuit 47a is selectively energized by a switch 59; the circuit 57a also receives the output voltage from the slide resistor 24 and serves to control the downward movement of the mold β via the electromagnet 55b of the valve 49 in a manner to be described below.

As previously described, the upward movement of the mold 6 during the formation of a container is controlled by the voltage comparator circuit 47 which, when it senses that the output voltage of the pusher stand has reached a predetermined value, de-energizes the solenoid 50a and closes the valve 49 centered position, whereby the hydraulic motor 35 is stopped. Ordinarily the form would continue to assume the position it stopped in; causes However, the voltage comparison circuit 47a (59 switch) "which receives at the moment in which the electromagnet is de-energized 50a, the same voltage from the shift resistor 24 in the presently-described operation, the energization of the solenoid 50b; the latter actuates the valve 49 in order to supply flow fluid to the opening 35b of the hydraulic motor 35, whereby the mold 6 is immediately moved downwards again about 12.7 mm). When the solenoid 50b is de-energized, the valve 49 is centered again and the mold 6 is stopped.

The final steps in forming the plastic container according to this procedure are shown in FIGS.

- 22 -

109834/1023

In Pig. 8, the container is essentially finished, - with-yourself the mold 6 is at the upper limit of its movement, with the Except that the plastic wall 60 has not yet adapted to the entire bottom part of the shape and a free space 6l between remains in the plastic and the mold. The next step shown in Fig. Is that the shape is a short piece is moved downwards (e.g. 12.7 mm) to place the plastic in a reverse bend to deform and a frustoconical recess 62 in the bottom part; during this step the substantially conical viand 60 'is stretched, whereby the conical wall 60 'is given an additional orientation will. It · is obvious that the next and final Step consists in making the opening from the top end the middle support rod 4 is taken, is closed. This process step has already been described above. the axial depth of the recess 62 of the downward pull of the mold 6 is usually made large enough that plastic surface 23, FIG. 10 is either coplanar with surface 64 or slightly above, which ensures stability when the container surface 64 rests on a support. The in essential conical recess 62 serves the purpose of strength to increase the bottom of the container, to improve its resistance to internal pressures and thereby improve the capacity for this purpose to keep the amount of plastic required as low as possible. In operation, the device according to the present invention is applied in the following manner: A thermoplastic polymer blank 1 is ..in-the extrusion chamber. 2 arranged. The extrusion ram 15 is operated so that it is a part of the non-melted thermoplastic polymeric material of the blank 1 through the annular extrusion passage opening 11 and into the annular groove 14 at the end of the mold cavity 5 presses. This first stage of extrusion one annular bead of the thermoplastic blank 1 is in Fig. 5 shown. It can be seen that the first part of the blank 1 to leave the annular extrusion passage opening and to penetrate into the annular groove 14, a. Bridge or membrane around the entire upper part of the annular

109834/102 3

BADQRI61NAI

F-2135/2135-R

Space 21 between the outside of the extrusion cylinder 3 and the inside of the mold cavity 5, whereby it forms a seal causes. The extrusion of the blank in the courage 14 allows the exercise of an axial in subsequent steps Pull on the extrusion by moving the mold to stretch or pull the extrusion.

Immediately after completion of the formation of the bead in the mold cavity 5 and in parallel with the continued movement of the extrusion ram 15, the mold 6 is moved at a steady speed and a fluid such as compressed air or pressurized liquid in a package is in the Fluid passage 8 is expressed from the fluid outlet ports 9 and 10 and into the cavity 1β. This cavity is defined by the outer surface of the mandrel 7 'of the extruded form 17 which has been extruded through the annular extrusion passage opening 11 and expanded by the pressurized air from the fluid outlet openings 9 and 10. This is illustrated in FIG. 4.

So when the mold 6 is opposite the extrusion passage opening 11 moves, anankert.der bead formed in the annular groove 14, the newly formed upper bottle end on the mold 6 and moves the fresh extrusion in an effective way past the compressed air flowing out of the outlet openings 9 and 10, whereby this extruded material is almost immediately pressed against the wall of the mold cavity 5 when it emerges from the opening 11.

The presently preferred method is principally concerned with producing a thermoplastic article with an uneven shell thickness due to the fact that the amount of extrusion and the speed of the mold are kept constant while the mold itself has a variable shape. It is known, however, that the jacket thickness can be controlled by appropriately programming the device to obtain either a uniform or a non-uniform thickness. Known methods of programming the jacket thickness include the steps of changing the speed of the

- 24 109834/1023

BATH

F-2135/2135-R.

sliding. Shape or the change in extrusion speed of the blank. - -

The thermoplastic polymeric material of the blank 1, which is extruded through the annular extrusion passage opening 11, is partially biaxially oriented by the extrusion process. The remainder of the desired biaxial orientation of the extrusion mold 17 is achieved by pulling the extrusion and stretching it against the surface of the mold cavity 5 which is in the mold. 6 is included. After pulling and stretching the extruded part, there is a significant reduction in calf thickness *, for example up to 50 % or more. The blank 1 is further pressed through the annular extrusion passage soff voltage 11 from the extrusion die 15, while the mold 6 moves in the direction of the second position over the mandrel 7. The combined effect of the extrusion of the blank 1 and its expansion 16 result in the desired shape of the bottle-shaped article 18 shown in FIG. 5, which however has an unsealed bottom part, as can be seen most clearly in FIG. The bottom portion of the bottle-shaped article 18 is thereby sealed in that the central support rod U is withdrawn while the mold 6 stops and the extrusion ram 15 continues to exert a force on the remaining polymeric material in the extrusion chamber 2. This is shown in Figure 5 with the fully .formed bottle-shaped article 19 which is in a highly biaxially oriented state. -

Figures 6 and 7 show the preferred method step in greater detail for sealing the floor, in which the partially

Withdrawal of the central support rod H allows the polymeric material of the parison under the continued pressure of the extrusion die 15 to flow inwardly to effect a seal. ·

On the other hand, the floor can also be sealed by a method that is disclosed in US patent application 57,679, and in which a friction-welded floor seal is produced on a thermoplastic surface by the floor

'- 25 V. '. 109834/1023

"135/213 *". ,

stA

of the thermoplastic bottle in the area immediately adjacent to the bottom opening is brought into contact with a rotating friction seal head to set the temperature of the thermoplastic material etvja. to increase its melting temperature and then the hot thermoplastic material is worked into the bottom opening and the bottom opening is sealed and then the sealed opening is quenched. This process can be performed while the bottle is still in the mold or in a separate operation after the bottle has been removed from the mold. Fig. 7 shows the position of the individual parts of the device at the end of the process for forming a hollow object from a hollow blank. In Fig. 7, the central support rod 4 has been withdrawn while the extrusion die 15 pushes the remaining part of the thermoplastic blank into the space which is released by the retracted central support rod H. In a modified embodiment, the device is modified in that a moving central support rod is provided instead of the stationary central rod through the blank. This enables a hollow closed-ended thermoplastic blank to be used in which the closed end becomes the bottom of the molded article, thereby eliminating the need for a separate process step to seal the bottom. Furthermore, the central rod and the blank move at the same speed during the extrusion of the blank, thereby eliminating relative movement between the blank and the central rod and minimizing the need for lubrication between the central rod and the blank and reducing wear · The central bar is lowered.

This modified embodiment is shown in FIGS. 11-13 when the method according to the invention is used. As shown in FIG. 11,] a hollow cylindrical blank 1 a with a closed end 65 is arranged in the extrusion chamber 2. The mold 6 is arranged in "a first position in which the Porm-

- 26 -109834/1023

cavity-5 surrounds the extrusion chamber 2. The middle rod ¹ Ja is arranged in the "inside" of the "blank" la and runs into the flow fluid passage chamber 8 in the mandrel 7. If necessary, the middle rod can be heated by known means, not shown, whereby the thermoplastic blank is heated . The extrusion die 15a is modified into a solid round rod which is located in the extrusion chamber 2 and abuts against the blank la which contains the central rod 4a. The central rod is biased against the extrusion die by known means, not shown, and exerts a desired force against the extrusion die sufficient to prevent the extrusion die from buckling the blank and ensure smooth movement during extrusion. In a typical embodiment, the extrusion die pressure is approximately 914 atmospheres and the preload pressure of the central rod is approximately 3 51 atmospheres. In operation, the extrusion die 15a forces the blank la out of the extrusion chamber 2 through the extrusion passage opening 11 and around the mandrel 7. FIG middle rod has moved with the blank so that there is no relative movement between the blank and the central rod. A fluid is introduced through the fluid channel 8 around the central rod 4a and passes through the opening 10 into the inner parts of the extruded jacket 17 » and presses it against the mold cavity, thereby forming the article. Figure 13 shows a fully formed article inside the mold cavity 6. It can be seen that the bottom of the blank 65 is now the central portion of the bottom of the article that part of the middle rod 4a, which was originally in the blank, while this in d he extrusion chamber had now been moved in the fluid channel 8. \

After the thermoplastic article is molded, it can be heat treated by known methods to the crystal density level increase, increasing the ability of gases to

- 27 τ

10 9834/1023 bad obkünal

Penetration of the jacket is reduced and the dimensional stability is improved, which is important when the article is to be used Used for filling hot drinks or in a pasteurization process is to be exposed to high temperatures and pressures.

The heat treatment is carried out at temperatures of approximately 1 * 10-220 ^° C., and the treatment time is relatively short. However, it is generally desirable to carry out the heat treatment for a time sufficient to produce a degree of crystallization in the finished product which is preferably at least between 30 and 50% or more, the highest possible crystallization for polyethylene terephthalate being about 60 % . In general, particularly good results have been observed when this heat treatment step is carried out over a period of 0.1-600 seconds. The upper limit of this treatment is not particularly critical, except from an economic point of view. A heat treatment time of up to 100 minutes is possible.

The thermoplastic blank used in the present invention is hollow, but under the term "hollow" is, unless otherwise stated, a tubular blank with open ends or to understand a tubular blank with an open and a closed end, i.e. a blind blank. The blank is arranged in the extrusion cylinder so that the closed end forms the bottom of the bottle. The tubular blank with open ends can be used in the device which has a stationary center rod or a movable center rod contains; however, a so-called blind blank can only be used in a device which has a movable central rod contains »·

The blank is preferably produced from thermoplastic material by conventional extrusion or injection molding processes, which is sensitive to increasing strength or reinforcement when biaxially oriented. The blank itself may or may not be biaxially oriented prior to use.

• - 28 1098 3 4/1023

BATHROOM O8K3INAL

P-2135/2135-R · ' _Λ . '

Palls - an 'oriented blank is used, a further drawing and expansion takes place during the extrusion of the extruded' blank. In addition, the blank should be practically made of amorphous material with a crystallinity of about 5 % and should be clear in appearance. A clear, shaped. bottle is then obtained. However, if a colored "bottle is to be produced: the colorant, such as a dye, can be added to the polymer forming the blank. A colored blank is then of course obtained. ·

The dimensions of the blank to be used are determined by many factors, - ^; "as of the desired thickness and degree of orientation. The typical blank is hollow and its radial dimensions are approximately equal to those of the neck of the bottle to be formed. The axial length of the blank is slightly less than the dimension between the tip and the center of the bottom, when measured on the outside of the bottle to be formed In order to improve the stability of the dimensions of the bottle, in particular the radial dimensions of the bottle neck, the blank with larger radial dimensions is formed to a temperature below The crystallization melting point of the polymer is cooled and then brought to approximately the intended radial dimensions of the bottle neck through a reducing nozzle. In order to achieve a further improvement in the stability of the dimensions, the blank can be compressed in a chamber with approximately the same outer diameter as the bottle neck with the help of a conical dome in the middle e of the compression chamber. In this way, a very short blank is obtained with an outside diameter about the size of the outside diameter of the bottle neck and with an inside diameter of practically 0. In this way, a very narrow cavity about the size of a needle hole is obtained the center of the blank runs. The compressed blanks are used in the device described above, in which the central rod is not present. .,. or · in which the central rod is fully retracted. ;, The method and apparatus of this invention can ^^ er. _: .-Applied to objects of various shapes and sizes

- 29 - '
109834/1023

BAD ORfGINAL

different thermoplastics. The preferred thermoplastic material is polyethylene terephthalate. and their mixed polymer mixtures, as described above, have been.

One reason that polyethylene terephthalate is preferred is that, when oriented, it has excellent strength, resistance to deformation and a low permeation factor, particularly with regard to carbon dioxide, oxygen and vapor. It is therefore extremely suitable for the production of containers for liquids / which are filled under pressure, such as soda, beer or aerosols. When molding polyethylene terephthalate, it is advantageous to start with a substantially amorphous material, that is, with a material having a crystallinity of no more than 5 % in order to obtain a clear bottle. . Useful Polyäthylenterephthalatpolymere have an inherent viscosity (1 / 5ige polymer concentration in a 37.5 or 62.5% solution of tetrachloroethane and phenol at 30 ⁰ C) of at least 0.55 · - ·

Preferably the inherent viscosity is at least 0.7 ₃ because this results in a bottle with significantly improved toughness properties, such as better impact strength. Impact resistance is measured by dropping a blank onto a concrete floor from different heights. In a drop test, which is carried out with a 15.24 cm long, amorphous polyethylene terephthalate with an inherent viscosity of about 1.1 with veneering of 3 blanks when testing with a wall thickness of about 3.50, 2.28 and 2, 36 mm with a weight of 27.8, 21.2 or 21.6 g, each blank is dropped twice from a height of 0.305 m, 0.609 m and 1.52 m, respectively. The blanks survive the fall without damage. In addition, each blank receives the blow of a 2.27 kg weight, which is dropped twice on the blank from a height of 0.305 m. j

Other useful thermoplastic materials are copolymers made of acrylonitrile / styrene / acrylate; Acrylonitrile / methacrylate; Methacrylonitrile polymerizate; Polycarbonates, polybis (pa-

-30 109834/1023

BATH

ra-aminocyelohexyl) do.decanamid and other polyamides; Polyformaldehyde; High pressure polyethylene and polypropylene, other polyesters and polyvinyl chloride. Laminated bottle walls or the like. can ^ be produced by the process according to the invention, by using hollow cylindrical blanks with laminated walls uses v / earth. Blanks with laminated walls are made by coaxial lamination of 2 or more blanks of the same or various thermoplastic mixtures. Prak- * Table examples of combinations are polyethylene terephthalate coaxially laminated on the inside with polyynylidene chloride copolymer or hydrolyzed ethylene vinyl acetate copolymers on the outside. .

Blanks made from multi-polymer mixtures can consist of two or more layers, i.e. preferably on three layers with the additional polymer sandwiched between the base polymer or the bottle-forming layers of the polymer. By using such a blank it is possible, bottles made of base resins with a chosen laminate manufacture that as 1) gas shield, 2) coloring layer or 3) serves as a degradative catalyst.

The extruded blank must have a temperature within the range of biaxial orientation, ie the temperature of the polymer to be used must be in the range in which the orientation is effected without straight-line drawing. The heat generated during extrusion is generally sufficient for these purposes so that the parison can be extruded at room temperature. The orientation temperature range, however, varies from polymer to polymer and is dependent on factors such as the crystallinity and the glass transition temperature of the polymer. If the orientation range of the polymer is so high that the heat of extrusion is not sufficient to increase the polymer temperature to its orientation range, so in this case the blank can be preheated prior to Strangpreßen "· The molded thermoplastic article is biaxially oriented and has physical Properties that match the type of blank used. . . ■ ·; ■■ -: ■ Λ-31--. . ■. "■■ ■. '■

109834/1023

The following examples illustrate the invention; · All parts, Percentages and ratios are parts by weight, percentages by weight and ratios by weight, unless otherwise specified.

example 1

Polyethylene terephthalate polymer having an inherent viscosity of about 0.96 is placed in a hollow cylindrical, amorphous molded blank 11.43 cm in length, an outside diameter (OD) of 17.27 mm and an inside diameter (ID) of 9.52 mm and a weight of about 22.6 g. The blank is pre-heated to about 92 ⁰ C 'and through the "T" port of about 0.838 mm at a cylinder temperature of about 85 ⁰ C in the apparatus described above extruded. The speed of the punch 15 is about 9.14 cm / second and the speed of the mold 6 is about 12.95 cm / second. Air of about 17.878 atmospheres pressure through the openings ¹ 9 and 10 are introduced. The inner mold diameter is approximately 6.35 cm.

A bottle is molded with a wall thickness of about 0.2895 mm;

ο the axial tensile strength is around 60.8 kg / cm and the

2 initial tension is about 1877 »24 kg / cm.

Example 2

Example 1 is repeated with - the following amendments: 1.0 inherent viscosity 109834 / 16.51 cm Blank length 1.727 cm Outside diameter of the blank 1.211 cm Inside diameter of the blank 23.5 g Weight of the blank 100 ⁰ C Preheating temperature 90-100 ^° C Cylinder temperature 0.889 cm opening 12.7 cm / sec. Piston speed 14.73 cm / sec. Molding speed 24.61 kg / cm ² Air pressure \ 562.46 kg / cm ² axial tensile strength 2029.23 kg / cm ² Circumferential tensile strength 0.4267 mm Wall thickness 32 - M023

F-2135/2135-R

33

Example 3 .

A thermoplastic plastic bottle is produced according to the method of Example 1, namely by extrusion and blow molding 'a hollow, cylindrical blank 11.43 cm in length with an outside diameter of 17.27 cm and an inside diameter of 0.91515 cm and "a Weight of about 22.6 g. The blank is made from polyethylene terephthalate - which has an inherent viscosity of 0.91. The blank has a density of 1.332 on the outer surface and 1.334 on the inner surface and a crystallinity of about 5 %. The bottle shows the following properties: I. Density and crystallinity of the polymer at various points on the bottle

throat

Upper end of the larger cylinder section Middle part of the larger cylinder section

Lower end of the larger cylinder section
Bottom of the bottle

Tensile strength & properties

Tensile strength (kg / cm)
Elongation (in %)
Tensile modulus (kg / cm)
Yield stress (kg / cm)
Biaxial orientation
X-ray orientation angle, • of the objects on the above
manner described was incorporated: 20 peak direction of rotation orientation

X (chi) f (phi) angle 17.0 "j plane perpendicular to axis 83 (axial) plane parallel to axis scanning 90 52 (circumference)

0 sampling 46 (circumference)

Kristalli density nity 1,332 0. 1,345 6th 1,356 17th 1.361 22nd 1,332 0 Axial - scope 0.548. 1.667 59 • 17th 17.29 48.019 0.464 0.703

Peak max. 0 ⁰ X

0 ° Χ ¹

0 ° X

- 33-109834 /1023

BAD ORiQiNAL

P-2135/2135-R to the 3V - fM "W W £ ~ * £". V 5 ° X 27.0 plane perpendicular axis 87 ° X Sampling O to the 32 Plane parallel axis 40 Sampling 90 (Scope) 0 sampling (Scope)

When considering the X-ray orientation angle and the the above tensile properties, the result for the bottle is an effective stretching ratio of about 3.5 x in the circumferential direction and about 1.25 x in the axial direction.

IV. Permeability

Jacket thickness' 0.4572 mm

Water loss 0.6 mg / hour

Bottle filled with water, stored at 17.5 % relative humidity at 25 ° C for 13 days "■

Carbon dioxide loss 1.5 cnr / day

Under a pressure of 2.8l8 atm Bottle standing at 25 ° C. The fla- (st andar dt see shows no permanent deformation and

Standard pressure)

mung

V. Deformation

Circumferential tube strips of the straight cylinder cross-section of a sacrificed bottle at 50 ⁰ C hold an initial ζ ug load of 351.5 ^ kg / cm after 100 minutes of deformation at a value of less than 2 % and with a long-term deformation of 60 days at a value of less than 5 % 'stood. This corresponds to a deformation constant of around 1.5.

- 34 -109834/1023 bad original

Claims (6)

P-2135/2135-R December 17, 1970 Hr Pa t e η t a η s ρ r ü c h e, 1. A hollow biaxially oriented article of polyethylene terephthalate having an inherent viscosity of at least 0.55 »characterized in that the Polyathylenterephthalat of the article has a density of about ₃₃₃₁ I ~ 1.402. 2. Article according to claim 1, characterized in that it is in the form of a generally cylindrical bottle; .-. '"-' 3. Article according to claim 2, characterized in that the straight cylinder cross-section of the bottle has an axial tensile strength of about 351 »^ ~ 2109.2 kg / cia, a circumferential tensile strength of about 1 ^ 06.2 - 5824.8 kg / cm and a circumferential yield stress of at least 492.1 kg / cm. 4. The article of claim 2, characterized in that the Bottle on average up to about 4 times in the axial direction and is stretched on average up to about 2.5 to 7 times in the circumferential direction. ■ 5. An article according to claim 2, characterized in that the bottle has a deformation ₃ which is equal to the curve of the logarithm (reciprocal value of the rate of expansion) against the expansion with a value of at least about 0.65v 6. The article according to claim 2, characterized in that the inherent viscosity of the polyethylene terephthalate at least is about 0.7. 7 »Object according to claim 2, characterized in that the Bottle in the straight cylinder cross-section has a crystallinity of 109 83A / 1023 BAD ORiSINAL F-2135/2135-R 3d » at least about 15 % . 8. An article according to claim 2, characterized in that the bottle is made of a polyethylene terephthalate mixed with a pigment is made. 9. Object according to claim 2, characterized in that the bottle has a straight cylinder jacket thickness of about 0.2539 to Ο, 7β2Ο mm and a weight-to-volume ratio (in g or cnr) of .about 0.2: 1 to 0.005 > 1. 10. The article according to claim 9, characterized in that the polyethylene terephthalate of the bottle has a crystallinity of at least about 15 % and the carbon dioxide penetration is no more than about 15 % in 30 days when the bottle is kept at room temperature and about under pressure of 5.27 atmospheres. ^: 11. The article according to claim 9, characterized in that the polyethylene terephthalate of the bottle has a crystallinity of at least about 15 % and that the oxygen penetration from the atmosphere into the bottle filled with a liquid and under an autogenous pressure of 5 ₃ 27 atmospheres at room temperature is no more than 5 parts per 1000 parts of liquid in 30 days. 12. The article according to claim 9, characterized in that the polyethylene terephthalate of the bottle has at least a crystallinity of about 15 % and that the water penetration from the bottle containing water and under an autogenous pressure of about 5.27 atmospheres at room temperature is no longer in 90 days than 5 % . 13. The article according to claim 3, characterized in that the bottle is made of polyethylene terephthalate with an inherent viscosity of at least about 0.7, that the straight cylinder cross-section of the bottle has a crystallinity of at least . - 36 - ■ 10983A / 1023 at least about 15 % and a jacket thickness of about 0.2539-0.7620 mm, that the bottle has a weight-to-volume ratio ■■ ' (in g or cm') of about 0.2; 1 to 0.005: 1, that the deformation constant equal to the curve of the logarithm (reciprocal value of the elongation rate) against the elongation has a value of at least about 0.65 and that the bottle has an oil penetration property, according to which the carbon dioxide penetration in 30 days is not more than 15 % , if the bottle is kept at room temperature and kept under an autogenous pressure of about 5.27 atmospheres, after which the oxygen penetration from the atmosphere into the with a Liquid-filled bottle under an autogenous pressure of 5.27 atmospheres at room temperature in 30 days is no more than 5 parts per 1000 parts of liquid and according to which the water. Penetration from the bottle, which contains water and is under an autogenous pressure of about 5.27 atmospheres, does not exceed 5 % in 90 days at room temperature. ■ ·: 14. The object of claim 13, characterized in that the Bottle made of polyethylene terephthalate mixed with a pigment will be produced. "" ·· - - - (15J A method for producing a hollow, biaxially oriented thermoplastic article, characterized in that it consists essentially of the following steps: (A) Extrude a blind, hollow cylindrical thermoplastic Blank with the open end first through an annular passage opening at a temperature inside of the biaxial orientation range to a relatively larger one To form the shape of the blank than the original shape of the raw lings is, as well as simultaneous (B) drawing and expanding the extrusion by a Liquid is pressed against the inner parts until the Extrusion expands to the shape of the article. 1.6. Method according to claim 15, characterized in that the hollow, thermoplastic blank through the ring-shaped passage - 37 - 109834/1023 BATH ORIGINAL F-2135/2135-R. _αβ : ■ ^r opening is extruded into a sliding shape, the
The mold has an annular, bead-like recess at one end of the mold for receiving and holding one end of the extrusion while the extrusion is being drawn and expanded in the direction of extrusion to conform to the shape by continuously moving the shape over the during extrusion Extrusion passage slides out while the extrusion is expanded by being pressed against the inner walls of the mold with the aid of a liquid introduced into the interior of the article to be molded. 17. The method according to claim 15, characterized in that the Direction of movement of the mold cavity is reversed after the drawing and expansion of the extrusion is finished and a recess is formed in the bottom of the object. 18. The method according to claim 15, characterized in that the hollow cylindrical thermoplastic extruded blank
is open at both ends and the procedure is the additional
Stages of forcing the trailing edges of the extruded blank radially inward toward the center of the article
to form a complete seal. 19. The method according to claim 18, characterized in that the direction of the sliding form is reversed after the drawing and expansion of the extrusion is completed and the
Recess is formed in the bottom of the object. 20. Apparatus for making a thermoplastic article from a blind, hollow cylindrical thermoplastic blank, consisting essentially of the following devices consists: (A) a slidable mold with a cavity shaped like that
is that he can produce the desired object; (B) an annular passage opening disposed in the mold cavity; (C) Means for extruding the open end of the blank - 38 109834/1023 BATH JJ first through the annular extrusion passage opening .in the shape; and (D) means in the mold for receiving the extruded blank and for forming and holding an annular, bead-like extrusion at one end of the mold cavity; (E) means for sliding the mold from one position to a second Position relative to the extrusion passage opening while the blank is continuously extruded, - to pull the extruded blank into the interior of the mold to form a hollow cylindrical shell from the extrusion; " (F) means for introducing a liquid against the interior of the hollow jacket, while the blank is extruded at the same time is to keep the hollow mantle against the inner boundaries to expand the shape. 21. The device according to claim 20 for the production of a thermoplastic Object made from a hollow cylindrical thermoplastic blank with open ends, characterized in that that the means for extruding the hollow thermoplastic blank are as follows: (A) an extrusion cylinder with an internal bore for receiving it of the hollow blank with the »extrusion end of the cylinder, which adjoins the annular extrusion passage opening and is axially aligned with it; (B) a stationary center rod in axial alignment with, and contained within, the extrusion cylinder, which is a tight fit Forms cavity, so that the hollow blank in the extrusion cavity with the center rod entering the hollow blank and the inner surface of the blind end of the blank touches, around the walls of the blank during extrusion to support, can be brought; and (G) a hollow thermoplastic stamp on the inside of the Extrusion cavity to contact the parison and the parison around 'the central rod through the extrusion port without moving the center bar with additives, in order to bring the rear edges of the extruded product radially inwards towards the center of the object under BATH P-2135/2135-R ι. · forcing a complete closure. 22. The device according to claim 20, characterized in that the means for introducing a liquid into the interior of the hollow Shell is a mandrel of uniform outer diameter, which is axially aligned in the mold with the extrusion cylinder and is provided with an inner liquid passage, which opens into 'a discharge opening, which is at the end of the mandrel located next to the adjacent annular passage opening. 23. Apparatus according to claim 20, characterized in that. the mold has a shaped cavity to form a generally to manufacture cylindrical bottle. 2k, device according to claim 20, characterized in that the means for extrusion of the hollow thermoplastic blank are as follows: (A) an extrusion cylinder, with an internal bore for receiving it of the hollow blank with the extrusion end of the cylinder adjoining the annular extrusion passage opening and is axially aligned with it; (B) a movable central rod in axial alignment with and contained within the extrusion cylinder, which is a tight fit Forms cavity, so that the hollow blank in the strand A 'pressh6h] clear with the central rod, which is inserted into the hollow blank penetrates and contacts the inner surface of the blind end of the parison to the walls of the parison during extrusion to support, can be brought; and (C) an extrusion die on the inside of the extrusion cavity, which contacts the outer surface of the blind end of the blank and passes the blank through the extrusion passage opening while at the same time the central rod on the inside of the blank is moved in the extrusion direction. 25. The device according to claim 2k for the production of a thermoplastic object from a hollow cylindrical ther- -MO- 109834/1023 H4 thermoplastic blank with open ends and with additives, . radially inward around the trailing edges of the extrusion to push towards the center of the object forming a complete seal. 26. Hollow thermoplastic blank, characterized in that that it is made of polyethylene terephthalate with an inherent viscosity of at least about 0.55. 27 · Biaxially oriented blank according to claim 26. 28. Blank according to claim 26, characterized in that both ends are open, ... 29. Blank according to claim 26, characterized in that a The end is closed. ■ 30. Blank according to claim 26, characterized in that it is made from a polyethylene terephthalate having an inherent viscosity of at least 0.7. . . 31. Blank according to claim 1, characterized in that it consists of amorphous material. 32. Blank according to claim 26, characterized in that it coaxially laminated with another thermoplastic blank 33. Blank according to claim 32, characterized in that the Polyethylene terephthalate blank coaxial on its outer surface is laminated with a blank made of polyvinylidene chloride. 3 * 1. Blank according to ANprüch 32, characterized in that the Polyethylene terephthalate blank on its outer surface with a blank made of hydrated ethylene-vinyl acetate copolymer is laminated. · 10983Λ / 1023 F-2135/2135-R Hi 35 · Blank according to claim 26, with radial dimensions of approximately. the size of the bottle neck to be formed and a slightly shorter axial length than the dimension between the tip and the center of the bottom when measuring along the outside of the bottle being molded. 36. Compressed to a certain size blank according to claim 3 ^> characterized in that the outer diameter of the The blank has approximately the dimension of the outer diameter of the bottle to be molded and the inner diameter is practically 0. - 42 109834/1023 BATHROOM OBlGiNAL L e r s e i t e VJ