DE2814952A1 - METHOD OF MANUFACTURING A PREFORM FOR AN AEROSOL BOTTLE - Google Patents

Description

DR.-ING. WALTER ABITZ DR. DIETER F. MORF DIPL.-PHYS. M. GRITSCHNEDER

Patent attorneys.

April 1978

Postal address / Posca. 1 Address P.O. Box. 86O1O9. SOOO Munich. 86

Pienzenauerstrasse 28

Phone. 98 32 22

Telegrams: Chemindus Munich Telex: CO) 523992

28U952

5 ¹ D- 251 5

EGG. DU POMT DE NEMORS AND COMPANY 10th and Market Streets, Wilmington, Del. 19898, V.St.A.

Process for the production of a gate molding for an aerosol bottle

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1. Field of application of the invention

This invention is an aerosol container that is a thermoplastic Includes bottle with an aerosol valve crimped therein. The bottle, whose body and neck preferably biaxially stretched is made by blow molding a preform using a core pin is formed with an outwardly protruding circumferential projection, which is used to form a circumferential, concave, inner surface portion at the uppermost part of the neck, which forms part of the preform, wherein this Upper surface section next to the flanged edge bead of the preform lies and the valve is crimped inside against this bead, which maintains the same size after the Blow molding process is finished.

2. description; the state of the art!

Glass or metal aerosol containers are known but have recognized limitations. For example, hang in the making of bottles used in such containers, their shape and appearance depend on the suitability of the cans and Bottle-making processes which in some respects lack the flexibility that is required in the manufacture of thermoplastic Bottles is given. Furthermore, these glass and metal bottles require greater care in handling and in use as thermoplastic bottles.

It has long been recognized that an aerosol canister that made using a thermoplastic bottle would have desirable properties that are not present in these glass and metal containers, since such containers are less expensive, safer (they For example, they would not explode or break), corrosion-free, lighter and more flexible in terms of design to name just a few such properties.

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As a result, various plastic aerosol containers have been developed; however, only special embodiments have proven useful, primarily genes, where a small, externally flanged aerosol valve is used to close the hash. Unfortunately is when using standardized aerosol valves, for example a 1 inch valve, as it is now used in connection with metal cans, the flare inside and required also a special shape of the bottle in the crimp area; there are no known thermoplastic! "tabs that one have such a shape.

It is typical of known aerosol containers, as is apparent from U.S. Patent 3,837,527 (Kutik et al.), That a container body made of plastic is closed by a lid closure with a dispensing valve. Such a container body is preferably made in one piece by injection molding. The container is not stretched for reasons that are still be explained, can be important, nor is there any indication that he is using, for example, a standardized 1 inch valve can be used.

Several methods are known for forming thermoplastic bottles. One method is blow molding. With the usual blow molding First, a parison is formed by extrusion of a thermoplastic tube softened by heat and the bottom is squeezed off, or, according to an alternative, by direct injection molding of the blowable geometric shape. Then the Parcel or blown preform is housed within a mold cavity that has the volumetric dimensions of the desired thermoplastic article, and the parison is expanded by applying pressurized air within the confines of the mold cavity is blown. The polymer is extruded and blown at elevated temperatures, namely above the stretching temperature range of the polymer. The manufactured article is not biaxially stretched. This process is economical but proportionate slow and, more importantly, the hollow bottles produced do not have the strength required for one Used for bottling beverages or other volatile liquids under pressure. 809842/0861

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Other known methods include the use of solid plastic rod sections used to form a hollow Object to be extruded. Becomes a solid section of rod extruded, the material that originally appeared on the axis of symmetry of the rod section finally appears lay, on the inner wall of the manufactured article and has a very strong roughness and other surface defects. The use of higher temperatures during the Forming the article tends to eliminate these disadvantageous properties, but prohibits its use a higher temperature, as this is caused by biaxial stretching of the plastic material during the cup formation obtained strength is lost by the heat relaxation.

However, there is a need for an economical process for the production of a plastic bottle, the properties of which make it useful for bottling liquids Make pressurized, such as carbonated beverages or aerosols.

Thus, strength can also be a problem with these plastic containers and it has long been known that it is possible to improve the strength of the bottle by stretching, preferably biaxially, the plastic neck and -to achieve the body of such a bottle during the molding of the same by other known methods, for example by stretch blow molding. The stretching gives the bottle the strength properties it has prior to such blow molding s process was missing.

However, it was not believed possible to use this type of process using a molded thermoplastic preform as it was not believed that a preform could be formed with the correct flare shape, if so a molding process using a core pin is used, as will be explained. This left a va-

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kuum, an unsolved problem for the professional world.

One was thus constantly striving before this invention, a to find thermoplastic bottle, preferably essentially using known methods and devices and which has the necessary structure for proper functioning.

In this context, as mentioned, a particular difficulty was in a thermoplastic bottle with a To create flanged edge bead, which is essentially similar like the flanged bands of existing metal and glass aerosol cans and bottles for receiving standardized valves, for example a 1 inch aerosol valve, or was identical to this. It is well known that licking and other troubles arise if this is the case The flare edge bead is not formed to critical tolerances so that it receives the valve and the flare within very narrow limits are made as necessary. Another problem is how the required strength in the Bottle is reached. The invention solves these problems.

One known method of making thermoplastic bottles of this general type is as previously mentioned was blow molding. In this and similar processes, a thermoplastic preform is first placed in a preform mold made, the mold walls and a core pin having a mold cavity between them in shape of the preform. Thermoplastic material in a molten or malleable state is in the mold cavity introduced to fill the same and then cooled to the shaped, preferably amorphous, preform to manufacture. Molding carried out in this way constitutes a particularly effective way of producing a preform, where demanding or precise dimensioning requirements are required, since the shape of the hollow shape alone is the shape of the Preform sets. IJaclidem the preform this way

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In this cavity, it is made into a bottle shape brought, reheated and blown against its mold walls to make the bottle. By using the right proportions in the manufacture of the preform and during Furthermore, by blow molding, it is possible to stretch the neck and the body of the bottle and thereby improve the strength thereof. One problem remained unsolved.

When trying to get an aerosol bottle of the desired size and stretching as desired on known apparatus using this known and desirable method to make a preform (which is then blown to form the bottle) using a Preform mold made by a core pin and mold walls is formed, it has still not been believed possible to produce a flanged bead of the correct dimensions. Such crimped bulges must have a certain critical, generally convex shape on their lowermost inner surface, so that the edge bead a standardized 1 inch flare valve and effective crimping of the valve against the crimp rim without leakage or other difficulty can allow .. To ensure that this is convex Form is present in the flanged edge bead, the inner surface of the preform must have a circumferential, concave inner surface part be formed directly next to the flanged edge bead, which in turn makes it necessary that the core pin surface sections having an outwardly protruding, circumferential Form a projection so that the flanged edge bead of the preform can be formed in the desired manner. Since the state of the art (only the use of core pins indicates with surfaces in order to form smooth inner surfaces without protrusions in the preform, so that the preform can be easily withdrawn from the core pin without damage, and as those skilled in the art believed that this would be the would be the only type of preform that could be made on a core pin, it seemed useless attempting to use a known device

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use, in which a core pin is used to form the inner surface of the preform, which is then used for manufacture the bottle is blow molded using an aerosol bottle regardless of how desired it would be this general type of blow molding technology.

There was therefore a need for a stretched thermoplastic Polyethylene terephthalate bottle made using a preform formed in a mold having a core pin and wherein the flanged edge bead the bottle is carefully monitored for dimensions so that it can accommodate a standardized 1-inch valve can, the dimensions being carefully and precisely adjusted during manufacture of the preform, and remain unchanged during the stretch blow molding process. The invention provides to meet this need Prior art includes a molded, thermoplastic preform that has a flanged edge bead the correct size, and a method of manufacture this preform using a core pin, a stretched thermoplastic bottle that is unchanged Flanged edge bead is made from this preform, and finally, with a flanged edge bead flanged against this flanged edge bead standardized aerosolvent, a thermoplastic aerosol container, which was not available to the relevant technology prior to the present invention.

Briefly summarized, the invention consists of an aerosol container, the following parts:

(a) A thermoplastic aerosol bottle made using a preform inserted into a core pin having a shape, the bottle having a solid crimp rim with a convex surface Has an aerosol valve, a biaxially stretched neck that is connected to the lowermost section

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of the flange edge bead is connected, and a biaxially stretched one connected to the lowermost neck portion Body, and

(b) an aerosol valve crimped against the crimped rim.

A process for the production of such a preform for an aerosol bottle contains the process steps:

Ca) molding a thermoplastic material in a mold that has mold walls and a mold core pin with means, which have a mold cavity in between in the form of a preform for the aerosol bottle, the at least one flanged edge bead has, as well as a section forming the bottle neck and a section forming the bottle body, said mold cavity forming means having a first surface arrangement for forming said flanged edge bead, a second surface arrangement for forming the portion forming the bottle neck and a third surface arrangement for shaping the portion forming the bottle body, and wherein the core pin has an outwardly directed, circumferential Has projection which has a convex surface portion of the second surface arrangement to form a circumferential, concave represents inner surface portion. at the top of the portion forming the bottle neck, and the convex surface portion of the second surface arrangement at a distance below the first surface arrangement of the Core pin lies and is connected to this, and

(b) removing the shaped material in the form of a preform for an aerosol bottle from the mold, including stripping the preform from the core pin, removing the preform is briefly deformed while he is from the circumferential,. lateral projection of the core pin is stripped off and then returns to its original shape.

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An aerosol bottle can be made using this particular preform therefor, the following parts having:

A flanged edge bead with a convex surface, a part forming the bottle neck which is connected to the lowermost portion of the flanging edge bead and the one has circumferential portion with a concave inner surface at its uppermost part, and

a bottle body forming portion connected to the lowermost part of the bottle neck forming portion is,

by means of a method comprising the steps of: blow molding the portion forming the bottle neck; and of the portion of the preform forming the bottle body to form an aerosol bottle having a biaxially stretched one Having neck and body.

This procedure may also include the following steps:

Heating the portions of the preform which form the bottle neck and the bottle body while the flanging edge bead thereof is heated is shielded from the heat prior to blow molding and

Preventing the flare from changing from its original one Mold, during blow molding of the heated, bottle neck and bottle body forming portions of the preform.

In the manufacture of erfxndungsgemassen aerosol container, an aerosol valve is crimped inwardly against the hemming Eandwulst, the dimensions of which, once they have been carefully once formed by molding in the VorformÜng form, using the novel _s VorforEling-mold ₂ previously described do not change, so that the flare can effectively accommodate a known valve, for example a 1 inch aerosol valve ₃ , which is flanged against the flare

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improved aerosol containers with a wide range of uses forms. By making the preforming ring using it with its new core pin ! form to ensure that the internal dimensions and shape of the preform are correct and as desired, is it possible to use well-known blow molding and other similar To use a process for the production of an elongated aerosol bottle which has a Bordel rim of the required shape and against which a standardized valve can be crimped to provide an improved thermoplastic aerosol container to accomplish.

In the drawings show:

Fig. 1 is a cross-section of a preform mold, wherein a Part, which is shown enlarged, and associated parts for the production of a preform, which is suitable for production a stretched aerosol bottle, all in accordance with the present invention,

2 shows a cross section of a bottle shape and associated parts for producing an aerosol bottle from a preform, which was produced in the form according to FIG. 1, also in accordance with the invention,

Figure 3 is a cross-section of a preform that is in the mold according to FIG. 1 and which is heated with the shielding of the flanging bead before it is used the bottle shape according to FIG. 2 blow molded into an aerosol bottle will,

Fig. 4- is an enlarged cross-section of a preform which in the preform - Jbrm according to FIG. 1 was produced, wherein the end. For the sake of clarity, parts have been broken away and different dimensions have been entered for clarity, before processing into an aerosol bottle, and

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FIG. 5 shows a cross-section similar to FIG. 4, ^{showing one from the preform according to S 1} Xg. 4 shows the aerosol bottle produced, as well as an aerosol valve in a position for crimping and crimped against the crimped bead of the bottle, whereby an aerosol container according to the invention is produced.

The invention relates essentially to the manufacture using biaxially oriented thermoplastic bottles of shaped preforms with a special shape, whereby the bottles have a standardized 1 inch valve or other valves, crimped internally against them to make an improved thermoplastic aerosol container.

When making an aerosol container using these bottles, the flanging of the aerosol valve is against the Flanged bead of the aerosol bottle is of great importance. Without a tight, reliable seal, the material seeps inside the container, for example, in an impermissibly large amount and the container does not meet the requirements placed on packaging. To ensure that the flare is correct, it is necessary to that the flanged Eandwulst is precisely defined in terms of its dimensions and shape in order to accommodate the aerosol valve. These requirements will be discussed in detail later. In brief, the flare should be constructed in such a way that that they have standardized valves, for example a so-called 1-inch aerosol valve part, as it corresponds to the state of the art, records.

It is desirable that standardized valves be used in the manufacture of the aerosol containers. For example, the standardized 1 _½ inch valve is used extensively with metallic aerosol cans and is available on the market easily and at relatively low cost, and the devices for filling and flanging the valve are also attached to them

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Cans available.

Among the other advantages of making aerosol containers using such a 1 inch valve gives better control of the wall thickness of bottles with the correct inside diameter using blow molding process, with blow ratios within recommended Areas lie.

Typical dimensions for the flanged edge bead of an aerosol bottle, that can accommodate a 1 inch aerosol valve in "The Aerosol Handbook", first edition, Wayne E. Durland Co., Caldwell, U. J., for example at page 219 ». From this it can be seen that parameters such as the thickness of the edge bead, the flanging depth and the flanging or inner diameter » and the radius of the flared valve is very important for a satisfactory seal of the valve against the Bottle are at the crimping. In particular are the inside diameter and the shape of the inner surface of the brothel rim of great importance, especially the clock hand area from 4-6, since here the valve is without a correct convex shape cannot be effectively crimped inside under the flared bead to enclose the valve and lock it in place hold and prevent excessive licking.

To ensure that the entire surface design the crimped edge bead of the stretched bottle is within acceptable tolerances and has the required shape, the bead must be manufactured with great care and preferably in a shaping step which can be easily controlled, for example by a classical one Injection molding process using a mold with mold walls and a mold core pin .. The difficulty existed before the present invention is to find a way to this critical optimal flanging surface of the flanging edge bead with their sophisticated convex shape using a core pin in a forming fixture. The invention

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solves this problem.

The solution lies essentially in finding a method of making a new molded preform using one a core pin and blow molding this preform. for the production of a stretched aerosol bottle of high strength, which was previously unknown to the professional world. During the manufacture of this bottle, the flanged edge bead remains with it shaped convex shape unchanged; thus, for the first time, a standardized aerosol valve can be crimped against the beaded edge to provide a new aerosol container with great utility in the art.

Description of preferred embodiments

An aerosol container according to the invention is shown in a partial view in FIG. This container, generally labeled C contains, in its preferred form, an elongated thermoplastic bottle, generally designated B and a standardized 1 inch (1,000 inch) aerosol valve V.

A preferred aerosol bottle B according to the invention is shown in FIG Fig. 2 and in a larger view in the area of the flanged edge bead in Fig. 5 This bottle has:

(a) a solid crimp hand bead 10 having a convex surface 11 to accommodate an aerosol valve,

(b) a biaxially stretched neck 12 connected to the lowermost portion of the flanged edge bead 10 and the one. circumferential surface section which facilitates the flanging 13 at its uppermost section, and

(c) a biaxially stretched body 14- which is the lowest Section of the neck 12 is connected.

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The concave inner surface portion of the bottle neck, which is part of the preform used to manufacture this bottle ensures, in part, that the flanged edge bead has the correct convex flanged surface 11, so that a standardized 1-inch valve V on the inside against the bead 10 can be flanged during the manufacture of the aerosol container C, as will be explained in more detail.

The bottle B is manufactured using a molded preform having a particular shape. This preform, which is generally designated by P, has according to Figs. 1, 3 and 4:

(a) a flanged edge bead 10 'with a convex surface 11' to accommodate an aerosol valve,

(b) form a bottle neck- ^ the section 12 ', which with the the lowest section of the BördeL-Randwulst is connected, and which at its uppermost part has a circumferential ^ concave ^ having inner surface portion 15, and

(c) a bottle body forming portion 14 'which is connected to the the lowest portion of the bottle neck forming portion 12 'is connected.

The preform P is preferably made of amorphous polyethylene terephthalate.

Preferably, the portion 12 'forming the bottle neck extends inwardly from the flange edge bead 10' and the the bottle body forming portion 14 'extends from the section 12 'forming the bottle neck downwards.

The circumferential »concave inner surface section 15 of the portion 12 'of the preform P forming the bottle neck preferably has a radius of at least about 0.635 (0.025 inch).

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The preform preferably has an inside diameter, as measured at the flanging bead 10 ', of about 2.54 mm (1,000 inches) and the thickness of the flanging bead 10' is about 0.33 πηβ (0.130 inches). In other words, the inner diameter of the preform, measured on the circumferential concave inner surface section 15 of the section 12 'forming the bottle neck, is preferably at least about 5 % larger than its inner diameter, measured on the flanged bead 10'.

Finally, the section 12 'of the preform which forms the bottle neck preferably extends from the beaded rim 10 · inwards and the section forming the bottle body 14 'extends from the bottle neck forming portion 12 'down.

The preform P is made in a mold that has a Has mold core pin which has an outwardly directed, circumferential projection which has a convex surface section to form the circumferential, concave, inner surface portion 15 at the uppermost portion of the the bottle neck forming portion 12 'of the preform P, the details of which will be explained in more detail.

A preferred method for producing such a preform for an aerosol bottle comprises the following steps:

(a) Forming a thermoplastic material in a form M according to, for example, FIG. 1, with the form M forming walls and 20 'and a mold core pin 21 which has means for forming an intermediate mold cavity 22 in the shape an aerosol bottle preform, which has at least an assembly 23 forming the crimp bead, an assembly 24 forming the neck of the bottle, and one forming the bottle body having forming assembly 25, the mold cavity forming assembly having a first surface assembly 26 for Formation of the flanging bead 10 ', a second surface arrangement 27 to form the bottle neck forming image

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Cut 12 'and a third surface assembly 28 for formation of the part 1V forming the body of the lap as part of the preform P has

and wherein the core pin 21 has an outwardly directed, circumferential side Has projection 29 which has a convex surface portion 30 of the second surface arrangement 27 to form of the circumferential concave inner surface portion 15 at the uppermost part of the portion 12 'of the preform P forming the bottle neck, as best shown in FIG. 4- is, and the convex surface portion 30 of the second Surface arrangement 27 at a distance below the first surface arrangement 26 of the core pin 21 lies, and is connected to this, and

(b) Taking out the molded material in the shape of the preform P for the aerosol bottle from the mold M, including of stripping the preform P from the core pin 21, wherein the preform P is briefly deformed when it is stripped from the circumferential projection 29 of the core pin, and then returns to its original shape.

An aerosol bottle can be produced using this particular preform P for this purpose by a process which includes the following steps

Blow molding of the bottle neck forming portion 12 * and of the portion .14 'of the preform which forms the bottle body to form an aerosol bottle with a biaxially stretched neck 12 and body 14 »

The method can furthermore comprise the further method steps;

Heating the neck of the bottle and llascheskörper forming portions 12 'and 14 ⁵ of the parison P before blow molding, during the hemming edge bead 10' is opposite to the heat shield and

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Prevent the flanging edge bead 10 'from changing its original shape during the blow removal of the heated , bottle neck and bottle body forming portions 12' and 14- 'of the preform.

Another preferred method of making a preform P for an aerosol bottle includes the following steps:

(a) Injecting a molten thermoplastic material into a first mold, for example a mold M, the mold Having mold walls and a mold core pin having means for forming an intermediate cavity in the shape of a preform for an aerosol bottle has' the at least a curling edge bead forming portion, a Bottle neck forming portion and forming a bottle body Section has,

said mold cavity forming means having a first surface arrangement to form the flanged tape bead, a second Surface arrangement for forming the portion forming the bottle neck and a third surface arrangement for formation of the portion forming the bottle body, and furthermore, the core pin has an outwardly directed, circumferential side Has projection having a convex surface portion of the second surface arrangement to form a circumferential, concave, inner surface section on the represents the uppermost part of the portion forming the bottle neck, and the convex surface portion of the times Surface arrangement below the first surface arrangement of the core pin and is connected to it,

(b) cooling the molten thermoplastic material in the first mold M ₁ and

(c) removing the cooled material as shopping parison P for an aerosol bottle from the first form M ₅ einseiiliesslieli stripping of the parison P from the core pin and the catching side to the projection Eernstifts so that the preform "

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ling P is briefly deformed while it is stripped from the core pin with the application of force and then reassumes its initial form.

As will also be explained, in the production of an aerosol container according to the invention, an aerosol valve is inserted on the inside crimped against the crimped edge bead of the bottle made from this preform, the dimensions of which, once they carefully using molding in the preform mold the new preform shape described above, have been formed, do not change, so that the edge bead effectively a known valve, for example a 1 inch aerosol valve, which can accommodate after crimping at the edge bead results in an improved aerosol container.

As mentioned, the portion forming the bottle neck and the portion forming the bottle body are the preform preferably made by stretch blow molding to give the aerosol bottle B with a biaxially stretched neck and Body to surrender. It is also preferred that this stretching-blowing is preceded by the following steps:

Heating of the bottle neck and bottle body forming Sections 12 'and 14-' of preform P, during the flanging edge bead 10 'of the preform is shielded against heating prior to blow molding.

Furthermore, the further process is in the manufacture of the bottle ens step, according to which the flanged edge bead on one Changing its initial shape is prevented while blow molding the heated, the bottle neck and bottle body forming sections of the preform takes place, of great importance.

3 shows a device 31 for shielding the flanged edge bead 10 'of the preform P against heating while

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it is held by a suitable arrangement, and that Heating his-forming the neck of the bottle and the body of the bottle Sections 12 'and 14 ·' of the same prior to blow molding the Preform P to form the stretched bottle B takes place. If so desired, the preform can continue during the Be held by the core pin. According to FIG. 3, the preform is after it has been stripped from the core pin and then has been brought into a starting position in the bottle manufacturing machine by a clamping device 33 in position on an internal mandrel 34 of the bottle making machine held.

Another preferred method of making an aerosol bottle comprises the following steps:

(a) Injecting a molten thermoplastic material into a first mold, e.g. Shape M,

the mold having mold walls and a mold core pin having means for forming a mold cavity therebetween in the form of an aerosol bottle preform, which has at least one beaded bead and one the Bottle neck forming portion and a bottle body forming portion.

the core pin has an outwardly directed, circumferential Has projection which has a convex surface portion of a second surface arrangement for forming a circumferential, has concave, inner surface portion at the uppermost part of the portion forming the bottle neck, and the convex surface portion of the second surface structure spaced below the first surface structure of the core pin and is connected to it,

(b) cooling the molten thermoplastic material in the first mold M,

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(c) removing the cooled material in the form of a preform P for an aerosol bottle from the first mold M, including stripping the preform P from the core pin and from the peripheral projection of the core pin, so that the preform is briefly deformed while it . is stripped from the core pin with the application of force and then resumes its original form,

and the preform has the following parts:

a solid bead with a convex surface to accommodate an aerosol valve V,

a bottleneck-forming section, which is connected to the lowermost Section of the flanging Eandwulst is connected, the Bottleneck-forming portion at its uppermost part has a circumferential, concave, inner surface portion and

a portion forming the bottle body, which is connected to the lowermost Part of the section forming the bottle neck is connected,

(d) heating those forming the neck and body of the bottle Sections of the preform P to a basin temperature,

(e) Blow-molding the sections of the preform P which form the heated bottle neck and the bubble body in a second Form for the production of a stretched aerosol bottle B and

(f) cooling and removing the stretched aerosol bottle B from the bottle mold.

The end result is a biaxially stretched aerosol bottle B with:

a solid bead with a convex surface to accommodate an aerosol valve,

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a biaxially stretched neck connected to the lowermost portion of the flanged rim, and a biaxially stretched body connected to the lowermost portion of the neck.

This bottle B has a circumferential side that facilitates flaring Surface section at the top of the neck of the bottle it and can be made using a molded preform that has a circumferential, concave, having inner surface portion at the uppermost part of the portion of the preform forming the bottle neck.

Using this bottle B it is possible to use an aerosol container C, which includes the following parts:

(a) a biaxially stretched thermoplastic aerosol bottle containing:

a firm Brödel rim with a convex surface to accommodate an aerosol valve,

a biaxially stretched neck connected to the lowermost portion of the flare rim, and a biaxially stretched body connected to the lowermost portion of the neck, and

(b) an aerosol valve flanged against the flared edge bead »

The aerosol bottle B of such a container C is preferably made of polyethylene terephthalate, but it can be made of other desired materials can be produced.

Furthermore, in such a container, G contains as best 5 shows that the valve V, which is flanged against the flanged edge bead 10 of the bottle B, has a flanged collar 35 a concave inner surface portion 36 and a Bead cap 37 having a convex inner surface portion 38. A typical 1-inch valve is preferably the? Radius of the concave inner surface section 36 of the

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beaded collar 35 about 1.2 mm (0.047 inch). Also, preferably, the curl depth, measured from the top plane of the bead cap 37 ^from V to the location of the maximum inside diameter of the bottom 35 of the curled collar, is about 4.7 mm (0.185 inches); the maximum inside diameter of the flanged collar 35 of the valve, as measured at its concave inner surface portion 36, is about 27> 2 mm (1.070 inches), and the minimum inside diameter of the bead cap 37 of the valve, as measured at the bead, is about 24.8 mm (0.976 inches) inch).

In other embodiments of the invention, the neck and body of the aerosol bottle B used to manufacture the aerosol container C is used, must be unstretched, especially in those cases where the strength requirements are not so great are. Further, if desired, a seal, such as shown at 39 in Fig. 5, between the Valve V and the flanging bead 10 be arranged; it however, it should be noted that the use of a seal is not required as long as a continuous one Contact between the outer concave surface 40 of the flanged edge bead portion 37 of the valve V and the convex surface Surface 11 of the flanged edge bead 10 in the critical flanged area the same is present.

A typical process for making a preform for an aerosol bottle and for the production of an aerosol bottle using this preform are now described:

Process for making the preform

Polyethylene terephthalate preforms according to the invention which each weighing 30 g and a total length of 11.4 cm (4.5 inches) with an outer diameter of 2.1 cm (0.830 inch) and an inner diameter of 1.74 cm (0.525 inch) for the 9,65 cm (3 by 8 inches) straight section were made from a Goodyear 3599 resin with an inherent viscosity

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from jV 0.9 produced in a commercially available injection molding machine, the shape of which comprises a core pin with an outwardly directed projection to form the concave inner surface portion at the top of the portion of the preform forming the bottle neck in accordance with the invention exhibited.

The operating conditions were as follows:

Extrusion temperature: feed 273 ° C (525 ° F)

Transition area 271 C (515 ° F)

Dispensing area 279 ° C (535 ° F)

Mold temperature 10 ° C (50 ° F)

Injection molding pressure 1st stage 550 bar (8000 ρsi)

2nd stage 482 bar (7000 ρsi)

Cycle time (sec.) Injection 16

Hold 9

Open 5

The cold, amorphous preforms made in this way were then pulled off the core pin with a snap and the neck formations took their initial exact dimensions again, as shaped.

Bottle making process

The brothel rim of each in that previously described The preform produced in this manner was held by a clamping sleeve 41, which can best be seen in FIGS is. Each collet had a stationary cavity 42 for holding and cooling the bead 10 'of the preform on. Only that. Holding lip 33 was divided into segments to insert the preform P and the subsequent To allow removal of the bottle made using this preform. A 0-ßing 4-3 was on the preform P, to keep the blown air. -A spring-loaded, articulated

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strengthened heat shield 31 used to shield the critical bead surface 10 'and for controlling the heating of the neck 12 ^f of the preform for the purpose of prevention of overheating and resultant thickness reduction of this area during blowing. The body of each preform, held in its non-advanced position by the hollow mandrel 34- was rotated and heated to 82-85 ° C using the heating elements 32, these heating elements being program-controlled to provide the desired temperature profiles.

At the beginning of the blowing cycle, the mandrel 34 was advanced to to expand the preform in the axial direction and thereby give it an axial stretching. Primary air with an overpressure of about 6.89 bar (100 psig) was simultaneously fed through the air holes 44 in the mandrel and blew the parison, while being axially stretched, partially up. After about 2 seconds, secondary air with an overpressure of about 41.3 bar (600 psig) through air holes 44 to stop the preform from expanding and achieve good Reproduction of the cool mold walls 45 and the mold bottom 46 introduced. The air was able to pass through the outlet openings 47 step out. After about 4 more seconds, the air with an overpressure of 41.3 had escaped and the split Mold walls 45, 45 '(sections) have been opened and mandrel 34 withdrawn to its position where it was not driven forward. The blown bottle B, which has an undistorted surface design of the Flanged edge beads 10 had, was of the clamping sleeve 41 by opening the retaining lip 33 uqö. Removal from the mold released. The cycle can then be repeated as desired.

Container tests

Those according to the invention, previously described Procedures made aerosol bottles had one satisfactorily high burst strength and resistance to

- 23 ~

808842/0881

FD-2515 r,

28U952

vertical bumps, while sxe were provided with the lid. For an additional test, a number of these bottles wax partially with a 20/80 mixture (weight basis) of Freon * 12 propellant / ethanol filled to ensure a test overpressure of approximately 1.72 bar (25 psig). The procedure to load these bottles with a standardized volume of 227 ml (8 fl.oz.) was as follows:

1. Each bottle was filled with 144 g of ethanol at 21 ° G (70 ° F) filled.

2. The bottle was then cleaned with Freon * 12 steam and a standardized 1-inch valve was against the Flared Eandwulst the bottle flanged to the invention to form a container.

3- Finally, 36 g of liquid Freon * 12 were passed through the Valve of each container is fed using a conventional pressure device.

A number of these pressurized containers have been operated at room temperature and 35 ° C (95 ° F) with the following results stored:

Tempe- time number of valve leaks% weight

temperature-tested loss

holder

Eaumt. 24 hours 53 0 0

Clears. 7 Say 14 0 0.03

35 ° C 5 days 10 1 0.55

(95 ° P)

The containers were sealed with 1-inch valves and, as previously described, under pressure, in each case were provided 10 containers with valves (1) neoprene gaskets ₅ (2) Faturgummidichtungen and (3) no seal "It

* registered trademark

- 24th

■ 3s.

FD-2515

the following percentage, commulative weight losses resulted when stored at room temperature:

Time (days) Neoprene natural rubber No seal 1 0.048 0.026 0.47 3 0.056 0.028 0.83 7th 0.061 0.029 1.04 14th 0.073 0.039 1.11 28 0.078 0.046 1.25 195 no no no modification modification modification

All results were useful. The usefulness of the valves without seals is particularly interesting. This allows a simpler, less expensive valve to be used, thereby saving a results in potentially significant cost savings. *

No such thermoplastic aerosol container made in the art has all of these features has, known; due to the present invention, this is now the pail. It is equally important that the Preform and the aerosol bottle from which the container is made using known devices can be manufactured with only changes in the "shape of the core pin" so that the critical shape the crimp bead of the bottle is obtained, giving those skilled in the art the improved thermoplastic by the invention formed aerosol container is made available.

End of description

- 25 809842/0861

Claims (1)

Claims Method for producing a preform for a Aerosol bottle, characterized in that it has the following Part contains: (a) molding a thermoplastic material in a mold, has the mold walls and a mold core pin with means, the between a mold cavity in the shape of a preform for an aerosol bottle with at least a beaded edge bead forming the neck of the bottle Section and form a section forming the bottle body, said mold cavity forming means having a first surface arrangement for forming said flanging bead, a second surface arrangement for forming the portion forming the bottle neck and a third surface arrangement for shaping the portion forming the bottle body, and wherein the core pin has an outwardly directed circumferential projection that is convex Surface section of the second surface arrangement for forming a circumferential, concave, inner surface section at the uppermost part of the portion forming the bottle neck., and this convex surface portion the second surface arrangement below the §0§ ^ H2 / 0§§1 ORIGINAL INSPECTED first surface arrangement of the Eernstift lies and with this is connected, and (b) Removing the molded material in the form of a Preform for an aerosol bottle from the mold, including the stripping of the preform from the core pin, with brief deformation of the preform, while this is stripped from the circumferential projection of the core pin, whereupon he then again takes on its initial form. 2. The method according to claim 1, characterized in that the thermoplastic material is a polyethylene terephthalate polymer is. 3- The method according to claim 1, characterized in that the thermoplastic material is injected into the mold. 4-. Method according to claim 3, characterized by the following further process steps: Heating the thermoplastic material to a molten state before injecting the material takes place in di-e form, and Cooling the heated material in the mold before the Preform is removed from the mold. 5. The method according to claim 1, characterized in that the preform is amorphous when removed from the mold. 6. Preform according to the method of claim 1 » 7. preform for an aerosol bottle, characterized by; (a) a flanged bead (10) with a convex surface for receiving an aerosol x ^r en.tils _s (b) a bottle neck (12) forming section, which with the lowest section of the flanged Eandwulst (10) connected - 2 = ■ 0 @ η t, 2/088 FD-2515 .3, 28U952 den and a circumferential concave inner surface abs has section (13) at its uppermost part, and (c) a bottle body (14) forming portion with is connected to the lowermost section of the section forming the bottle neck (12). 8. Preform according to claim 7 »characterized in that the circumferential concave inner surface section (13) of the section forming the bottle neck (12) Eadius of at least 0.635 now (0.025 inch). 9- preform according to claim 7 * characterized in that its inside diameter, measured on the flanged bead (10 ') is approximately 2.54 cm (1,000 inches). 10. Preform according to claim 7 »characterized in that the thickness of the bead about 3 * 3 mm (0 * 130 inch) is. 11. Preform according to claim 7 »characterized in that its inside diameter, measured on the lower, concave, inner surface portion (15) of the bottle neck (12) forming section is at least about 5 % larger than its inner diameter, measured on the flanging Eandwulst (10 '). 12. Preform according to claim 7 »characterized in that it is made of amorphous polyethylene terephthalate. 13. Preform according to claim 7, characterized in that the section forming the bottle neck (12) extends inwardly from the crimping bead (10 ') and that the section forming the bottle body extends from the section forming the bottle neck (12 ^f ) extends downwards. - 3 _ 0098 * 2/0881 } 2 81A 9 5 2 14-. Preform after. Claim 7 »characterized in that it is produced in a mold (M) with a mold core pin (21) which has an outwardly directed, circumferential projection (29) which has a convex surface section (30) for forming the circumferential, having concave, inner surface portion (15) at the uppermost part of the portion of the preform ^{which forms the bottle neck (I2 r).} 15- preform according to claim 14, characterized in that the preform is manufactured by injection molding. 16. Process for the production of an aerosol bottle from an aerosol bottle preform comprising the following parts: a beaded edge bead with a convex surface, a bottle neck forming section, which is with the lowermost Section of the flanged edge bead is connected and the one circumferential, concave, inner surface on his Has uppermost portion, and a bottle body forming portion with the the lowest section of the bottle neck forming section is connected, ' characterized in that the method includes the method step of Blow molding the bottle neck forming portion and the bottle body forming portion of the preform to form an aerosol bottle with a biaxially elongated neck and body. 17 · The method according to claim 16, characterized by the further process step of heating the bottle neck and bottle body forming portions of the preform, while the flanged Eandwulst of the same .before blow molding is shielded from the heat. 18. The method according to claim 17, characterized by the further process step, according to which the crimping ~ 28H952 The edge bead is prevented from changing its initial shape during the blow molding of the heated ones Bottle neck and bottle body forming sections of the preform takes place. .19. Process for the production of an aerosol bottle, characterized through the following process steps: (a) injecting a molten thermoplastic material into a first mold, the mold walls and a mold core has means, the between a mold cavity in the form of an aerosol bottle preform with at least one Bordel rim bead, a section forming the neck of the bottle and form a bottle body forming portion, said mold cavity forming means having a first surface arrangement for forming said flanged rim, a second surface arrangement for forming the portion forming the bottle neck and a third surface having a surface arrangement for forming the portion forming the bottle body, and the core pin has an outwardly directed, circumferential side Has projection having a convex surface portion of the second surface arrangement for Formation of a circumferential, concave, inner surface section at the uppermost part of the bottle neck forming portion, and this convex surface portion the second surface arrangement spaced below the first surface arrangement of the core pin and is connected to this, (b) cooling the molten thermoplastic material in the first mold, (c) removing the cooled material in the form of an aerosol bottle preform from the first mold, including the stripping of the preform from the core pin and from the peripheral projection of the core pin, so that the preform is briefly deformed while PD.2515. ₆ 28U952 it is stripped from the core pin under the action of force and then again assumes its initial shape, with the preform having a fixed flanged edge bead has a convex surface for receiving an aerosol valve, a bottle neck forming portion which is connected to the lowermost portion of the flanged edge bead and at its uppermost portion has a circumferential concave inner surface ^{portion, N a} tab body forming portion which is connected to the lowermost portion of the "bottle neck forming portion, (d) heating the bottle neck and bottle body forming Sections of the Yorforraling to a saddle temperature, and (e) blow molding the heated bottle neck and bottle body forming portions of the preform in one second form for the production of a stretched aerosol bottle. 20. The method according to claim 191, characterized in that the thermoplastic material is a polyethylene terephthalate polymer is. 21. Biaxially oriented aerosol bottle, characterized by: a fixed flanged edge bead (10) with a convex surface for receiving an aerosol valve (V), and a biaxially stretched neck (12) ₃ with the lowest section of the flanged edge bead (10) is connected, and a biaxially oriented body (14), OCE ^m is connected to it the lowest portion of the neck (12). In that the neck (12) 22- Aerosol bottle according to claim 21, characterized in that a circumferential _s ,, convex inner surface portion (11) at its uppermost part. §09842 / 0811 2314952 23- aerosol bottle according to claim 21, characterized in that that they are made using a shaped Yorformling (M) with a circumferential, concave, inner surface portion (15) is made on the uppermost part of the portion of the bottle forming the neck of the bottle. . 24 ·. Aerosol containers, characterized by: (a) a biaxially stretched thermoplastic aerosol bottle with a fixed bead (10) with a convex surface for receiving an aerosol valve (V), a biaxially stretched neck (12) connected to the lowermost portion of the flanged edge bead (10), and a biaxially stretched body (14) connected to the lowermost portion of the neck (12), and (b) an aerosol valve (V) flanged against the flanged edge bead (10). 25 · Aerosol container according to claim 24, characterized in that that the aerosol bottle made of polyethylene terephthalate is. 26. Aerosol container according to claim 24, characterized in that the flanged against the flanged edge bead (10) Valve (V) has a crimped collar (35) with a concave inner surface portion. 27- aerosol container according to claim 26, characterized in that that the radius of the concave inner surface portion of the curled collar (35) is about 1.19 mm (0.047 inch) amounts to. - · 28. Aerosol container according to claim 24, characterized in that the valve is a 1-inch valve and against the Crimped edge bead (10) in the crimped state has a crimp cap (37) with a convex inner surface section and a curled collar (35) with a concave having inner surface portion. 80S8A2 / 0 ⁷⁸⁸¹ 7 4952 29- aerosol container according to claim 28, characterized in that the flange depth, measured from the top of the Flared cap (37) of the valve in place of the maximum inner diameter of the flanged collar (35) of the valve about 4.70 mm (0.185 inch) and the maximum inside diameter of the flanged collar (35) of the valve, measured on the concave inner surface portion thereof, is about 27.2 mm (1.070 inches). 30. Aerosol container according to claim 28, characterized in that the minimum inner diameter of the crimp cap (37) of the valve, measured on the flanged bead (10), is about 24.8 mm (0.976 inches). 31. · One-piece, thermoplastic aerosol bottle, marked by a solid flanged edge bead (10) with a convex surface for receiving an aerosol valve, one with the lowest section of the flanged bead (10) connected neck (12) and a body (14) connected to the lowermost portion of the neck (12) using the bottle a molded preform is made, the a bottle neck (12) forming portion and a circumferential, concave, inner surface section at the uppermost part of the portion forming the neck. 32. One-piece aerosol container, characterized in that it contains the following parts: (a) a thermoplastic aerosol bottle with a Fixed bead (1O) with a convex surface to accommodate an aerosol valve (V), a neck (12) connected to the lowermost portion of the flanging bead (10) and a body connected to the lowermost section of the neck (12), and 809842/0881 28U952 (b) one that is crimped against the crimped edge bead (10) Aerosol valve (V). 33. Container after. Claim 32, characterized in that the inside diameter, measured at the beaded edge, is about 25.4 mm (1,000 inches). - 9 -809842/086 1