DE2655411A1 - METHOD AND DEVICE FOR APPLYING A PLASTIC COATING TO GLASS CONTAINERS - Google Patents

Description

Dr. Hans-Heinrich Willrath t

Dr. Dieter Weber Dipl.-Phys. Klaus Seiffert

PATENT LAWYERS

D-62 WIESB * DLN Dec. 3, 1976 P.O. Box ■■ 6145

Gustav-Freytag-Strasse is II / Wh

S- (06121) 3727H)

Telegram address: WILLPATENT Telex: 4-186 247

1150 A 51-75 N

Wheaton Industries, Millville, New Jersey, USA

Method and device for applying a plastic coating on glass containers

Priorities: Serial Nos. 638 679

and 638 680 of December 8, 1975

and 731 995 of October 13, 1976

in USA

The invention relates to a method for continuous application a thermoplastic protective coating on glass containers and specifically such a process that is intended to to produce a very thin, extremely uniform coating of high quality, especially in terms of clarity and transparency.

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Numerous attempts have been made to find methods of applying

plastic coatings on glass containers, especially for packaging pressurized beverages. These Overlays have been used to protect the surface of the glass containers from scratching, to prevent fragments in the event of breakage to contain as well as for decorative purposes.

The use of fluidized bed thermoplastic coating powders, in which heated containers are immersed, to create a Effecting coating is described in U.S. Patent 3,857,498 and U.S. Patent 3,901,180. The latter patent is particularly concerned with an apparatus for applying the thermoplastic coating by a fluidized bed process in continuous Way.

The known coating methods for continuous application However, a plastic coating on glass containers does not consistently produce a thin, clear coating high quality. To some extent, these problems arise because the prior art methods make the coating thickness less uniform than is desirable. This in turn affects the clarity. Also is a large average coating thickness required to maintain a predetermined minimum thickness, and this affects the economics of the process. The lack of uniformity and the requirement associated with it thicker coatings to avoid defects has also been a problem with fluidized bed coating in general. Also were previously glossy and clear coatings in fluidized bed processes not available with consistent quality.

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It is therefore an object of the present invention to provide a fluidized bed coating process for glass containers with a very thin and extremely uniform coating of high quality is produced.

A more specific object of the invention is to obtain such a method in which glass containers are continuously passed through Immersion in a fluidized bed can be coated to provide a high quality and consistently very clear, very thin and very even plastic film to get on the surface of the container.

These and other goals, the latter in the course of the following Description of the invention will become clear, is achieved briefly with a method in which by immersion in Glass containers to be coated in a fluidized bed of thermoplastic powder are first thermally conditioned in such a way that that a high degree of temperature uniformity is achieved in the entire containers to be coated. This can by soaking the container for a prolonged period of time, such as for at least 10 minutes in an oven (the preheat conditioning chamber) at a tightly set one Temperature on the order of 5.5 to 11 ° C (10 to 20 F) above the desired coating temperature take place. The term "coating temperature" as it is as used herein means the temperature of the surfaces of the containers immediately prior to immersion in the fluidized bed. This temperature varies depending on the properties of the powder of the coating material. Generally, the coating temperature selected such that the powder of the coating

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materials is somewhat flowable, on the to be coated Surface is deposited and adhered to a predetermined and uniform thickness, then to a clear coating can melt and that the temperature is below the temperature at which oxidative degradation occurs.

Within a short time after removal from the preheat conditioning chamber, in the order of 10 to 15 seconds, the containers are immersed in the fluidized bed of powder of the thermoplastic coating material for 2 to 5 seconds and then transferred to a reheat conditioning chamber in which the containers and the coating thereon are included a regulated speed, on the order of 14 C. (25 F) per minute, to a final temperature just below that temperature at which a substantial oxidative degradation of the coating takes place within a relatively short time. The containers then become an intermediate chamber where they are spontaneously transferred at a controlled rate, on the order of 28 C (50 F) per minute allowed to cool to a temperature at which the flowability of the coating powder is negligible. The containers are then left continue at a controlled rate (such as by compressed air cooling) to a temperature just above the polymer crystallization temperature of the thermoplastic coating to cool down. Rapid cooling of the coating above its glass transition temperature range takes place by quenching with a liquid at a temperature below the lower limit of the Glass transition temperature range of the coating, but above ambient temperature, to avoid the formation of stresses in the glass container walls to prevent.

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Furthermore, the coated containers can be further lubricated and rinse water are treated and dried.

The temperature uniformity in the entire glass containers prior to immersion in the fluidized bed in the process of the present invention can be obtained by interrupts conventional tempering or heating in a baking muffle at a point where the containers are just below the coating temperature for the method according to the invention and then to the coating temperature in a thermal conditioning chamber similar to that which is otherwise in the Method of the present invention used can be reheated. In this case there is less residence time in the Preheat conditioning chamber required as if the process were used for coating containers that are to be placed on Ambient temperature has let cool down.

In any case, the heat conditioning prior to coating in the method according to the invention is intended to achieve a relatively constant temperature not only on the surface of all containers to be coated, but also essentially in the Ensuring the entirety of the walls of the tanks at all points of each tank. This is how the inclination of containers in the center of a muffle to be hotter, or the tendency of thicker parts of the container to act as a heat sink or source of heat making the coating uneven, avoided working.

But besides ensuring adherence of a thin but very uniform coating of thermoplastic coating powder from the fluidized bed on the entire outer surface of each container, the present invention provides a qualitative

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tiv high-quality and extremely evenly coated product, also due to the carefully regulated temperature conditioning after coating as outlined above.

In general, the coating must be in a flowable (elevated temperature) state for some time to get an even and complete fusing of the coating powder. If the powder coating is too fast or If the temperature is too high or if it is kept at an elevated temperature for too long, the oxidative degradation of the coating will occur a problem. The post-heating conditioning is intended to ensure that the entire coating material is in a highly flowable state is brought to avoid errors resulting from a lack of complete fusion of the coating, while at the same time avoiding overheating of the material, as is the case with too fast Overheating or excessive heating temperature and yellowing or burning of the coating would lead.

Similarly, cooling the coating too quickly from its highly flowable state at the end of the post-heating can cause formation cause haze, and the use of quenching to cause the coating to rapidly pass through its polymeric crystallization zone is critical to produce a clear coating. At the same time the lower temperature is allowed during the quenching phase should not be too low, otherwise tensions will build up in the walls of the glass containers. This is a critical factor peculiar to fluid bed coating of glass containers, as in other types

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of coating processes, the glass containers are generally cooler than the coating material on their surface. ·

A preferred coating material in the method according to present invention is a thermoplastic ionic copolymer of ethylene to which a fluidizing material, like fine-grained silica powder. One such Coating powder is from E.I. duPont de Nemours and Company under the trade designation Surlyn, and such fluidizing additives are available under the trade name Aerosil and Tillanox available.

For a more specific description of the coating powder preferred in the method of the present invention Reference is made to U.S. Patent 3,264,272. Coating powders of this type are especially copolymers of polyethylene and o (, ß-ethylenically unsaturated carboxylic acids, especially those which are neutralized by metal ions. The most preferred coating powder with which the present Process developed and to which the various process temperatures described herein relate is a ionic copolymer of ethylene and 11% by weight methacrylic acid having a melt index of 20, with 40% of the carboxylic acid groups of the copolymer being neutralized with sodium ions. In general, this most preferred coating powder is relatively flowable above about 177 ° C (350 ° F) and is not significantly subject to oxidative degradation (other than prolonged heating) below about 218 ° C (425 ° F). The preferred one Bottle coating temperature with this material is about 182 to 210 ° C (about 360 to 410 ° F). At the-

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At this temperature, the powder is deposited in a fine layer evenly on the surface to be coated and adheres at it. Complete fusing is achieved by gradually heating in the post-heating chamber to a temperature guaranteed just below the temperature at which an oxidative degradation is essential, and in / by the coated Hold the container at this elevated temperature (with the coating in a flowable state) for a few minutes.

For a better understanding of the invention there now follows a more detailed description thereof with reference to FIG Drawing. In this mean

Figs. 1A and

Fig. 1B together a side view of the apparatus according to the present Invention for coating glass containers in series in a fluidized bed.

Figure 2 is a top plan view of that in Figures 1A and 1B shown apartment.

Figure 3 is an enlarged cross-section on the line 3-3 in Figure 1A of the apparatus shown in Figure 1A.

FIG. 4 is an enlarged section of a portion of the mechanism shown in FIG. 3 with certain elements the same in an alternative position.

Fig. 5 is an enlarged cross-section on line 5-5 in Fig. 1A of a portion of the apparatus shown in Fig. 1A.

Figure 6 is a detail view on level 6-6 of Figure 5 of a portion of the mechanism shown therein.

FIG. 7 is a section on line 7-7 of another part of the mechanism shown in FIG.

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FIG. 8 is a detailed illustration of a portion of that shown in FIG. 5 mechanism shown with certain elements of the same in an alternative position to that shown in FIG.

Fig. 9 is a detail cross section of part of that in Fig. 1A apparatus shown in level 9-9 of the same.

Fig. 10 is a detailed cross-section on the plane 10-10 of in Mechanism shown in Fig. 9.

Fig. 11 and

Fig. 12 are detailed representations in the levels 11-11 and 12-12 of the apparatus shown in Figure 1B.

Figure 13 is a detail cross-section on the plane 13-13 of one Part of the apparatus shown in Figure 1A.

FIG. 14 is a detail side view of the mechanism shown in FIG. 13.

Figure 15 is a perspective view of the chuck bar transport system in the apparatus shown in the previous figures.

Fig. 16 is a detailed cross-section on the plane 16-16 of Fig Fig. 15 shown mechanism, and

Fig. 17 is a graph showing the relationship of the surface temperature of the containers to be coated at the time shows while the container is going through the various stages of the method according to the present invention Invention go through.

The invention will now be made preferred with reference first Apparatus for carrying out the coating process described.

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1A, 1B and 2, a container discharge furnace 2 and a Temperaturvorkonditionierkaramer 4 with the container 6 on shown one end of this.

The container 6, or more precisely a plurality of such containers, as shown in Fig. 3, is removed from the furnace 2 by rotating movement of the motor 8 removed, which via the clutch brake 9 and the speed-reducing gear housing 10 with the crank arm 12 is connected, and this is pivotably connected via the connecting part 14 to a second crank arm 16, which in turn rotates the shaft 18 on which a pair of container lift arms 20 are mounted.

At the end of each container lifting arm 20, the arm 20 is opposite the point at which it is attached to the shaft 18, pivotally connected to a vertical hanger 22. At each end of each container lifting arm 20 this is also pivotally attached to spacers 24, which in turn are pivotable with opposite ends of a parallelogram forming part 26, and this part is in turn connected to a second shaft 28 at its upper end which is rotated by a third crank arm 30, and the latter rotates in unison with the shaft 18.

The arrangement of the lifting arms 20 and the parallelogram forming Part 26 along with the hangers 22 and other hanging elements is constructed so that the lifting arms shifted or further changed transversely to the direction of general container movement in the machine, i.e. vertically downward in Fig. 2, with the help of the cylinder 32, which is fixedly on one end of the frame part 34 and with its other

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the end of which is attached to the sliding sleeve 36 with the projection 38 which the latter in a groove for that in the Shaft 18 engages.

After removing from the end of the furnace 2, containers 6 are put through the apparatus for coating containers in series with it conveyed a fluidized bed according to the invention from left to right, as shown in Figs. 1A, 1B and 2, while them on one of a series of chuck bars 38 with end portions 40 hang down, the latter being supported by rollers 42, which in turn rest on transfer rail segments 43, and 46 rest. The transfer rail segments 43, 44 and 46 are in turn on different fixed frame parts supported, including parts 48, 49, 50, 51, 52 and The chuck bars 38 are spaced at the breaks in the transfer rail segments 43, 44 and 46 through the rod holder 54 of the removal station and the rod holder 56 of the immersion station supported.

In Fig. 1A, the container lifting arm 20 and its associated

Device including hangers 22 and rods or above

holder 54 of the removal station in the upright / position immediately shown before the transfer of containers lengthways along the machine. The same arrangement is also in dash-dotted lines Lines are shown in their lower position ready for container removal.

The fluidized bed coating is carried out in the apparatus of FIGS. 1A, 1B and 2 by immersing the container 6 in a tub 58, containing fluidized thermoplastic powder while the containers are at elevated temperature. Thermoplastic powder,

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that comes into contact with the hot container side walls melts and forms a coating on these side walls.

Immersion of the container 6 in the fluidized bed coating tub takes place by the action of the piston 60, which at its lower End is connected to a horizontal frame part 62 and at its upper end to a transverse part 64, the latter in turn, is attached to a pair of vertically movable Stangenauf hanging parts 66, which in turn is attached to the Rod holder 56 are attached to the immersion station. Even with the vertically movable rod suspension parts 66 are racks 68 and a pair of anti-pinch gears 70 on one common shaft 72 fixed, which extend transversely to the machine and mounted in the longitudinal side frame parts 73 are.

To the right of the fluidized bed coating tub 58, the containers pass one after the other through the soaking chamber 74, the air cooling chamber 76, the spray quenching chamber 78, and then to the container discharge station 80.

Near the right end of that shown in FIGS. 1A, 1B and 2 Apparatus, as best seen in Figures 1B and 2, this apparatus includes the motor 82, its shaft with the rotor 88 is connected, and this carries cam followers 86 and 88, which engage in the longitudinal transfer plate 90, and this is in turn attached to sleeves 92 for causing longitudinal movement of the transfer tubes 94. Limited rotation of the transfer tubes 94 is carried out by pivotally connected connectors 190 and 192 which, in turn, are connected to the shaft 98 connected, and the latter will have a limited intermittent

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rotating movement (in alternating directions) is given by the piston 100, which is connected at one end to the frame part 102 and is attached at the opposite end to a location on the circumference of the crank arm 104 at the end of the shaft 98. Of the Frame extension 106 and the guides 108 form a pick-up point for containers at the removal station 80 and a pick-up point for chuck bars 38 after removal of the containers 6 of these to return the chuck bars 38 to the left end of the apparatus. Mechanical facilities for the automatic fulfillment of these functions, especially for the discharge and pick-up of containers and the return of the bars 3 8 to the container receiving station of the machine are included in a more preferred embodiment of this apparatus.

Referring now to Figures 3 and 4, the mechanism for receiving containers 6 from oven 2 is detailed before and after container attachment shown. More specifically there is a chuck rod 38 and a plurality of chucks hanging from it shown with chuck necks 110 and container neck supports 112.

The mounting rod 114 holds the chuck necks 110 in place an upright position prior to the interlocking of the chucks and containers. At the left end, as in FIG. 3, access is seen pushing the rod mount 54 of the pick-up station into the toothed rack 116, which in turn engages in the toothed wheel 118 and via this into a second toothed rack 120. The gear 118 is mounted on a shaft with a crank arm 122 which engages a feeder spring 124, and this is in turn attached to the fixed frame part 126.

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The second rack 120 is fixed to the transverse direction slidable rod 128 attached, which is carried by rollers 130. Located on the transversely slidable rod 128 a plurality of container neck support members 132. The abutment 134 limits the movement of the rod 128 to the right, while the adjustable abutment screw 137 is so arranged is that it is inwardly onto the end piece 139 of the mounting rod 114 with the coordinated leftward movement of the chuck rod 38 and its associated device and fasteners and the rightward movement of the rod 128 and the device connected to it.

After gripping containers, as shown in Figure 4, the chuck bar 38 returns to the level of the transfer rail segments 43, 44 and 46 lifted and folded across to their lateral starting position.

The manner in which the containers 6 are so hung is best seen in FIGS. 5-8. Specifically in Fig. 5 the chuck neck 110 is shown having an upwardly directed Has extension 110A which is slidably disposed in the chuck carrier 136 and through the spring 138 downwards is forced. An air passage 140 extends downward through the upwardly extending extension 110A of the chuck neck 110. A portion 142 with reduced Diameter on the outer surface of the upwardly extending Neck extension 110A is designed to be in the Slot 144 in the mounting rod 114 engages. So depends

or upper the chuck neck 110 in its upright / position, as in FIG

Fig. 8 is shown with the mounting rod 114 in the am

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leftmost position. Movement of the mounting rod 114 to the right allows the chuck neck 110 moves downward over the containers 6 as shown in FIG. A fastening and spring means 146 in the Chuck rod end portion 40 tends to be the mounting rod 114 positive in one of its two predetermined positions to store when this device engages in slots provided in the mounting rod end piece 139 for this purpose are. ,

Rollers 42 rest on a frame part 148, which in turn is supported on an inwardly extending channel 150 which is attached to the transfer rail segment 46. Openings 153 in channel 150 in each position or station for the chuck bars 38 along the length of the machine are designed to have pivotably attached anchoring devices 152 held in anchoring engagement by the spring 156. More specifically, the fastener pushes 158, engaging fastener slot 160, pivotally mounted anchor member 152 in FIG an anchoring position in the channel 150.

Clockwise movement of transfer tube 94 and engagement of stop 154 with the pivotally mounted anchor member 152 frees end piece 40 and chuck rod 38 for longitudinal movement by the longitudinal engagement of the stop 154 in the slot 162 of the end portion 40, so that upon longitudinal movement of the transfer tube 94, the chuck rod 38 is moved longitudinally into engagement therewith. In order to achieve such a longitudinal movement of the transfer tube 94

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it is for a sliding movement in the support shoulder parts 164 mounted and rests on the roller bearing part 166 of the transfer rail segment 46. Channel and rack parts are also connected to transfer rail segments 43 and 44.

To facilitate the passage of air down through the chuck neck 110 and over the top of the container neck 7, when container 6 in the fluidized thermoplastic powder Are immersed in the fluidized bed in the tub 58, the end portion 40 contains air passages 158 which communicate with the inner Cavity of the chuck rod 38 are in communication, so that pressurized air introduced through air passages 168 an outlet down through air passages 140 and the upwardly extending portion 110A of the chuck neck 110 finds.

As can be seen in FIGS. 9 and 10, the rod mount contains 56 of the immersion station a connection 170, which through an air passage 172 to air outlets 174 in an air

passageway engaging portion 176 extends through spring 178 is pushed inwards. Inclined surfaces 180 are provided on part 176 for the mating of the air outlets 174 with the outer end of the air passages 168 in the end portion 40 of the chuck rod 38 to facilitate.

In operation of the apparatus for coating containers in series with the aid of a fluidized bed according to the invention containers picked up from furnace 2 gradually through several intermediate stations along the length of the next

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the 80 arc segments of the single revolution of the motor 82 convicted. To return the transfer tubes 94 to their original positions, the motor 82 is operated with a single Rotation rotated in the opposite direction.

During the dwell time between two forward movements of the longitudinal transfer plate 90, i.e. after the cam follower 86 has advanced the transfer device and before the cam follower 88 is engaged, by the second stage To effect the forward movement of the device, the piston 100 is actuated and operates via the crank arm 104, the Shaft 98 and disc 188 via pivotally connected shock members 190 and 192 to push opposing crank arms 194, thereby engaging the transfer tubes 94 in opposite directions. At a connection point at 100, each of the transfer tubes 94 is passed through a T-shaped plug section 202 and a corresponding, matching receiving groove 204 divided. As seen in FIG is, the corresponding receiving groove 204 allows a limited angular movement between the two halves of the transfer tubes 94 interconnected in this way. More specifically, the receiving groove 104 is designed to have a limited rotational movement of the rear portions of the transfer tubes 94 without corresponding angular movement of the front Sections of transfer tube 94 are permitted. In this way when the second stage of the transfer movement of the transfer tubes 94 is from left to right in these drawings caused by the cam follower 86 rotates the right portions of the transfer tubes 94 upward so that the stops 152 out of engagement with the chuck bars

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arrive at their respective container stations. In this way, the containers move further away lying stations by the second stage of the longitudinal movement of the transfer tubes 94, while those containers are at the closer stations are not moved. To return To effect the transfer tubes 94 to their home positions, tabs 206 are on the left hand portions of FIG Transfer tubes 94 attached. The lugs 206 sit on supports 208 during the transfer movement of the transfer tubes 94 and upon completion of the second stage of that movement they come into engagement with the nose receiving part 210, which is then moved downward by piston 212 to the return both longitudinal halves of each of the transfer tubes 94 to the same angular position. The return movement of the Transfer tubes 94 by means of cam followers 86 and 88 are then carried out as described above, and the transfer mechanism is now ready for the next cycle.

With reference to the apparatus explained and described above the method of the present invention is now described, especially when it is carried out using the apparatus explained and described above.

It should first be noted that this process can be used for any wide range thermoplastic fluidized bed tüber Zug powder is suitable for permanent, high-quality and very clear, thin (on the order of 0.1 mm - 4 mils) and uniform (in the range of 0.075 to 0.15 mm - 3 to 6 mils) coatings. Preferably will this coating is formed from resins of the type described above,

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including especially those mentioned above as most preferred. The coating powder is in the fluidized bed coating tank fluidized with air at a pressure of 0.068 to 0.27 at (1 to 4 psi) supplied by a porous plate is introduced, covering the bottom of the fluidized bed container forming a fluidized bed on the order of 305 to 610 mm (12 to 24 inches) high. to create. Clean, dry air at a temperature below 38 ° C (100 ° F) is required for this purpose. Although the Details of the fluidized bed container are not explained here, the container can generally have an overflow trough or Have outer container with a small gap between the inner and outer container, which latter as The overflow trough is used to collect excess powder. A vacuum can be applied to this trough to avoid powder loss to avoid and to prevent contamination of the surrounding air space.

An important feature of the method according to the present invention is the careful thermal conditioning of the containers before and after coating. Special is a critical one Factor the lack of uniform surface temperature and uniform thermal properties of different containers in a row of containers and even on different parts of the same container. The present invention eliminates those : undesirable conditions with the help of a thermal conditioning chamber before immersing the containers to be coated in the fluidized bed coating material. This can be done by a relative long residence time in the heat conditioning preheating furnace 4

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Instead, containers that have already been preheated to a higher temperature, such as those that have been preheated by a Post-production annealing furnace or a conditioning stoving muffle are taken directly from such annealing furnaces or stoving muffles with a temperature just below that, necessary for fluidized bed coating in the method and apparatus of the present invention. the Containers are then placed over a relatively small temperature range, on the order of 11 to 22 ° C (20 to 40 ° F) in heated again in a heat conditioning furnace 4.

In this way, a highly straight and good temperature uniformity is obtained in the entire containers to be coated Heat transfer properties. With the preferred coating powder according to the present invention, those to be coated Containers in a preconditioning chamber to about 191 heated to 218 ° C (375 to 425 ° F), preferably to about 204 ° C (400 ° F). When leaving the thermal conditioning chamber there is a delay on the order of 10 to 15 seconds, preferably closer to 10 seconds prior to immersing the containers in the fluidized bed coating container. The containers with their surfaces at a temperature in the range of 182 to 210 ° C (360 to 410 ° F), preferably at a temperature of about 204 ° C (400 ° F) are then on the order of 1 to 5 seconds, preferably closer to 2 seconds Seconds, immersed, during which time the temperature of the surface of the now coated container increased to about 149 ° C (300 ° F) and then rise back to 204 C (400 F) as a result of the heat contained in the container walls begins.

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At this point a second fluidized bed tank can be added engaged in the process of the invention (and in the apparatus explained for the purpose of describing the invention) will. Such a second container can be used for a second immersion to form a similarly uniform one second coat to bring the total coating thickness to 0.2 to 0.3 minutes (8 to 12 mils).

After the dip coating, the containers enter the reheat conditioning chamber one where they run at a controlled rate, preferably on the order of 14 ° C (25 F) per minute, heated to the upper temperature limit of the post-heating chamber, i.e. in the case of the coating powder 218 C which is preferably used according to the invention (425 F). In this post-heating conditioning chamber, the coating powder is completely melted, but becomes an oxidative one Degradation of the powder through the regulated and controlled heating rate, heating time and upper temperature limit avoided. Among other things, this probably avoids local overheating, which is likely to cause such degradation could cause.

After the post-heating conditioning chamber, the containers go through a regulated cooling temperature where the coated Allow container to cool to approximately 350 ° F (177 ° C).

The coated containers then go through a second cooling stage, where it is pressurized to a temperature just above the upper limit of the glass transition temperature of the coating powder be cooled down. To get maximum shine and

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To get maximum clarity of the coating, this must be the coating applied powders are cooled through the range of glass transition temperature as quickly as possible, and this is carried out according to the present invention by flowing a liquid, such as water, over the coating in order to reduce the temperature change as quickly as possible without destroying the coating as a result of the impact of a spray jet or of To effect droplets.

A critical feature of the present invention is that the coated glass containers are free from stress generation to cool down in it. It is especially important in the deterrent stage. For this purpose, the quenching liquid is used, general Water, to a temperature above ambient, generally on the order of 54 C (130 ° F) heated in the range of 46 to 63 ° C (115 to 145 ° F) so that cooling through the polymer crystallization zone (about 93 to 74 ° C in the case of the preferred coating powder according to the present invention) takes place with the smallest possible stress formation. Then the coated container surface can be sprayed with a lubricant to minimize scratching of the surface and by the effect of the lubricant to facilitate handling in filling and packaging machines. The lubricant is applied generally by rinsing and subsequent drying to produce the finished coated product, a container with a clear, glossy plastic coating of extremely uniform thickness on the order of 0.075 to 0.15 mm (3rd up to 6 mils).

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The critical time-temperature relationship in the method according to the invention is illustrated by the graph in FIG explains where the surface temperature of a glass container, determined by optical pyrometry, recorded as the container exits the preheat conditioning chamber goes to the immersion station and is immersed there, enters the Nachhexzkonditionierkainmer, then to the chamber for controlled cooling (referred to as the transition phase in the time-temperature diagram) and finally to the cooling, quenching, Lubricant, rinse, and drying stages go.

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Claims (49)

Claims 1. Method for applying a plastic coating to glass containers by heating the containers and immersing them in a fluidized bed of a thermoplastic coating powder, characterized in that the containers are soaked in a preconditioning oven for a sufficiently long time that essentially all parts of each container reach a substantially constant predetermined coating temperature. 2. The method according to claim 1, characterized in that the Ambient air for 10 to 15 minutes before immersion Seconds, especially 10 seconds. 3. The method according to claim 1 and 2, characterized in that one immersing the container for 1 to 5 seconds, preferably 2 seconds. 4. The method according to claim 1 to 3, characterized in that the container after immersion in a regulated manner Post-ex-immersion temperature above the predetermined pre-immersion temperature, but exposes below the temperature at which accelerated oxidative degradation of the coating on the containers entry. 5. The method according to claim 4, characterized in that according to heated after immersion so that there is a temperature rise on the surface of the coated container in the order of magnitude of 14 ° C (25 ° F) per minute. 6. The method according to claim 1 to 5, characterized in that the coated container is controlled by the temperature 709825/0890 original inspected temperature after immersion to a temperature just above the polymer crystallization temperature range of the coating cools and then rapidly by quenching through that area to a temperature following the quenching cools above ambient temperature. 7. The method according to claim 6, characterized in that the quenching by flooding the surfaces of the coated Container with a quenching liquid of a temperature below of the polymer crystallization temperature range and above ambient temperature. 8. The method according to claim 1 to 7, characterized in that one the quenched coated container is then cooled to ambient temperature with a lubricant and a washing liquid sprinkles and dries. 9. The method according to claim 1 to 8, characterized in that one Remove the containers from a tempering furnace or a baking muffle with a slightly before being immersed temperature lower than the predetermined temperature prior to immersion and then exposed to the preconditioning oven. 10. The method according to claim 1 to 9, characterized in that one as thermoplastic coating powder, a copolymer of ethylene and 11% by weight methacrylic acid, of which 40% are carboxyl groups neutralized with sodium, with a melt index of 11 used. 11. The method according to claim 1 to 10, characterized in that a coating powder is used which has a fine-grained fluidizing Includes powder. 709825/0890 - 16 - 12. The method according to claims 1 to 11, characterized in that • the coating temperature is from 182 to 210 ° e (340- to 410 ° F) used. ' 13. The method according to claim 1 to 12, characterized in that after immersion, heating is carried out such that a temperature rise on the surfaces of the coated containers in the order of 14 ° C (25 ^ F) per minute up to a final temperature after immersion of about 218 ° C '(425 ° · F) ". ■ ' ■■ -'- ■ ''' ^: ' ■ 14. The method according to claim 1 to 13, characterized in that the container of the temperature after immersion with at a rate of about 28 ° C (50 F) per minute Cools 177 ° C (3S0 ° F) and then forcibly cools to about 104 ° C (220 ° F), at which temperature they are quenched with water, the water being at 54 ° C (130 F). 15 ^ Device for performing the method according to claim 1 to 14, characterized by -en a) a 'container or bottle receiving device, wherein clamping ^: include chuck rod end pieces with means for supporting the end pieces on a pair of pick-up station transfer rail segments; means for moving the pick-up station's transfer rail segments between a lower pick-up position at which the containers or bottles are picked up and a higher transfer position from which the containers or bottles are picked up Bottles can be transferred to the subsequent processing stations, the transfer rail segments in this latter position 7 0 9 8 2 B / 0 8 9 0 originally inspected - Vl - the receiving station with other transfer rail segments align in the machine, b) a first pair of stationary transfer rail segments, which are adapted to attach one of the chuck bars with chucks thereon to the pair of transfer rail segments transfer to the receiving station, c) Means for immersing the containers or bottles hanging on the chuck bars from a predetermined one Position after a transfer from the rail elements of the receiving station into a fluidized bed of a thermoplastic Coating powder, d) a second pair of stationary transfer rail segments, which are arranged to transfer bottles or containers from the rail members of the coating station record, and e) Means for transferring the chuck bars along these transfer rail segments. 16. The device according to claim 15, characterized in that the Transfer rail moving device of the receiving station comprises a pair of crank arms, one end of which is pivotable with the transfer rail segments of the receiving station connected is. 17. Apparatus according to claim 15 and 16, characterized in that that the crank arms have means for maintaining the transfer rail segments the receiving station in a horizontal position in all radial positions of the crank arms lock in. 709825/0890 18. Device according to claim 15 to 17 / characterized in that that their crank arms are designed so that they the transfer rail segments the receiving station both horizontally to the subsequent processing stations and vertically move to the transfer position. 19 .. Device according to claim 15 to 18, characterized in that the chuck engaging means means for moving the crank arms in the transverse direction causing the chuck rod to move lock in. 20. Apparatus according to claim 15 to 19, characterized in that they also have a pair of transfer rail segments of the coating station with lifting and lowering facilities having. 21. Apparatus according to claim 15 to 20, characterized in that they have facilities for introducing pressurized gas into the chuck caps simultaneously with the operation of the container immersion facilities having. 22. Apparatus according to claim 15 to 21, characterized in that the chuck bar transfer device has a pair of elongated pusher parts with pusher stops on each pusher part, extending substantially away from that part and toward the other part of that pair, in spaced apart positions along its length, anchoring-unanchoring means for reversible rotation of the elongate parts about their axes to effect an engagement and reach out of the handle stops in and out of the end share, transfer devices for reversible movement of the elongated parts in the longitudinal direction 709825/0890 G. 265S411 to bring about a transfer of the container or bottle holding devices includes along the support member. 23. The apparatus according to claim 15 to 22, characterized in that the end parts are a steerably mounted, biased by a spring Anchoring part for engaging a part receiving the anchoring part at a distance in predetermined positions enclose along the support part corresponding to the spaced-apart positions of the handle stops on the elongate handle parts, wherein the anchoring parts are formed so that they stop by engagement of the pusher with the end share in get non-anchoring positions. 24. Apparatus according to claim 15 to 23, characterized in that a) each of the elongate pusher parts from at least two longitudinal sections consists of mating T-shaped pressure-transmitting plug and connector projections with a Distances that allow radial movement between them over a limited arc are connected to one another, b) the anchoring-unanchoring devices and the pressure-transmitting devices T-shaped projections are designed so that they cut a rotation of the longitudinal from in unison with the Anchoring the stops in these end sections while allowing these sections to be independent of one another are rotated in the opposite direction from the unanchoring rotation, c) the anchoring-unanchoring device successive Means for rotating at least a pair of portions of the elongate pusher members relative to the floating one 70982 5/089 0 or anchored rotary position includes, while the pusher parts are in a longitudinal transfer position between their limits of their longitudinal movement, the anchoring-unanchoring device further means for rotating the remaining pairs of sections of the elongate pusher members to the floating or unanchored positions include the same, while the elongated pusher parts the Limit their longitudinal movement at the longitudinal transfer end positions reach, the successive bodies cause the anchoring-unanchoring device to rotate the elongated pusher parts into the anchored, in the end part engaging position upon return of the elongate pusher parts to the longitudinal transfer starting position to cause. 25. The device according to claim 15 to 24, characterized by a Thermal conditioning chamber for treating containers or bottles before inserting the containers or bottles into the receiving device. 26. The device according to claim 15 to 25, characterized by at least a heat conditioning room after conditioning the Containers or bottles, the second pair of stationary transfer rail segments goes through this room. 27. The device according to claim 15 to 26, characterized by a bottle holding chuck with 1. a horizontally arranged "Y-shaped" portion which has a bottle resting thereon on a generally horizontal surface on the outer surface near the top End of the bottle supports and 2. a cap part that can be loosely slipped over the top of the bottle and so yours 709825/0890 prevents horizontal movement, the horizontally disposed part and the cap part cooperatively arranged in such a way are that they carry a bottle placed thereon and hanging thereon, with substantially the entire bottle underneath this surface is free from contact with any part of the chuck. 28. The device according to claim 27, characterized in that the cap part is closed at one end and so the Prevents foreign matter from entering the interior of the bottle while the bottle is being held by the chuck. 29. Apparatus according to claim 27 and 28, characterized in that the cap part · means for introducing compressed air has inside. 30. Apparatus according to claim 27 to 29, characterized in that the cap part · vertically · movable in a chuck carrier part is. 31. The device according to claim 27 to 30, characterized in that that the cap member has an upwardly extending portion with a recess therein which is formed so that they have a horizontally · arranged part · that the cap part · in or upper
upright position, the cap part being able to fall freely when this horizontally arranged holding part is moved horizontally and this part emerges from the recess. 32. Apparatus according to claim 31, characterized in that the Cap part · is forced downwards. 709825/0890 _ το ■ _ 33. Apparatus according to claim 27 to 32, characterized in that that a plurality of the chucks including the chuck mounts in spaced apart positions on a chuck rod are attached, wherein the chucks are designed so that they are with a first horizontal movement of the rod and the chuck to the bottles and the open end or upper of the U-shaped parts with the cap parts in their upright Positions and then by a second vertically downward movement of the cap parts over the bottles with them in Intervention coming » 34. Apparatus according to claim 15 to 33, characterized by a bottle receiving device with bottle holding chucks and chuck rods and with a second rod in a bottle receiving position , the second rod being arranged parallel to the chuck rod, the bottle neck holders hanging on the second rod in spaced positions are directly opposite the open ends of the U-shaped chuck members, the second bar is adapted to remain in the bottle receiving position, and the chuck bar is one of several such chuck bars, each adapted to face the receiving station and is convicted away from this. 35. Apparatus according to claim 34, characterized by chuck engagement devices for simultaneous movement of the second rod with the bottle neck brackets and the chuck rod in the bottle receiving position with the U-shaped chuck parts to each other so that bottle necks come into engagement between them, means which cause the cap 709825/0890 - '46. 2 6 b 5 A 11 parts fall over the bottle necks, and devices that subsequently cause the neck brackets and U-shaped Return parts to their original positions. 36. Apparatus according to claim 35, characterized in that the chuck engagement device has a first one with the chuck rod rack connected in the bottle receiving division to move in unison with it during the first movement, a second rack connected to the second rack and a gear engaging in both racks for the simultaneous Having movement of the same in opposite directions. 37. Apparatus according to claim 36, characterized by additional Means for returning the gear and the racks to their starting positions. 38. Apparatus according to claim 35 to 37, characterized in that the cap parts in their raised position through horizontally arranged holding parts are held, which in slots in the upwardly extending parts of the cap parts engage with one end of the retainer extending from the chuck rod and constructed to be in the one control part near the limit of the / plant to the bottle opposite movement of the chuck rod and the second The rod engages with the control member causing the retaining member to disengage from the chuck cap member. 39. Apparatus according to claim 15 to 38, characterized by a Container or bottle holding device with a chuck bar and bottle holding chucks, the chuck bar Has end portions with rollers which are adapted to rest on support members and the chuck rod between the support parts. 709825/0890 -X- 40. Apparatus according to claim 39, characterized in that the End portions also include transfer engaging devices; which are designed so that they pusher devices for transferring the container or bottle holding device along the support device. 41. Device according to claim 15 to 4O, characterized in that that it has a container or bottle transfer device with container or bottle holding devices that the Push-button devices consisting of a pair of elongated push-button parts with push-button stops on each push-button part, which are essentially extending away from the part and towards the other part of the pair, at intervals along the length of the container or Bottle holding device exist that anchoring-unanchoring devices for the reversible rotation of the elongate parts about their axis to effect engagement and his Solution of the pusher stops provided in said end parts and that transfer devices for reversible motion the elongate members in the longitudinal direction for effecting a transfer along said bottle holder the support part are provided. 42. Apparatus according to claim 41, characterized in that the End members include a pivotally attached, spring biased anchor member that engages in anchor member receiving members engages, which at predetermined intervals along the support part corresponding to the distances of the trigger stops • the elongated pusher parts are arranged, the anchoring parts are adapted to be moved to a non-anchoring position by engagement of the trigger stops in the end portions can be set. 70982B / 0890 43. Apparatus according to claim 41 and 42, characterized in that the elongate pusher parts are cylindrical or tubular are designed and rest on roller bearings, which facilitate their rotary and longitudinal movement. 44. Apparatus according to claim 41 to 43, characterized in that the elongate pusher parts consist of at least two longitudinal sections exist, which by matching T-shaped force-transmitting or non-positive plug and plug projections with a distance therebetween allowing radial movement therebetween over a limited arc are. 45. Apparatus according to claim 41 to 44, characterized in that the anchoring-unanchoring devices and the force-transmitting or non-positive T-shaped projections are formed so that the longitudinal sections in unison the anchoring of the stops in the end sections are rotated, while these rotating sections are independent of one another can be rotated in the reverse or loosening or de-anchoring rotary motion. 46. Apparatus according to claim 41 to 45, characterized in that the anchoring-unanchoring device is a sequential device includes engaging at least a pair of portions of the elongated pusher members in disengaged, unanchored rotational motion can be rotated while the handle parts are in a middle position between their limits of longitudinal movement, that the anchoring-unanchoring devices continue Include facilities that insert the remaining pairs of sections of the elongated pusher members into the unanchored. 709825/0890 Rotate the released position of the same when the elongated pusher parts the limit of their longitudinal movement in the longitudinal transfer end positions achieve that the sequencer also causes the anchoring-unanchoring means to all elongate Bring pusher parts to the return of the elongated pusher parts to the longitudinal transfer starting position rotated to the anchored end member engaging position. 47. Apparatus according to claim 15 to 46, characterized in that it has a transport mechanism for objects, which by one or more combinations of equally spaced, linear arranged stations are to be conveyed, wherein the objects are held in a holder with end parts, which are so formed are that they are from a pair of transfer rails are supported, which run along these stations, and are movable along their length, that a pair of elongated Pusher parts or pushing devices parallel to the transfer rails with end part engagement pusher abutments that fit into the end parts engage, are arranged at intervals along the length of the handle parts according to the positions of the stations, that the stops extend towards the space between the rails, anchoring-unanchoring devices so formed are that the elongated pusher parts or pushing devices rotate in opposite directions and so the stops cause to engage and disengage from the end portions and that longitudinal transfer means for movement the pusher parts in the longitudinal direction from their starting position in the direction of the objects to be transferred, while 709825/0890 rend the stops are in their engaged position, and for transferring the handle parts from their end position to their starting position while the stops are disengaged or are in their released position, are provided. 48. Apparatus according to claim 47, characterized in that the end parts means for anchoring the end parts in predetermined Positions along the rail with the transfer part stops disengaged from the end parts, lock in. 49. Apparatus according to claim 47 and 48, characterized in that the pair of elongated pusher parts or pushing devices is divided into at least two pairs of subsegments which are attached to one another adjacent segments by a power transmission connection or force-fit connection of T-shaped mating Plug and plug projections are connected to one another, the projections are formed so that they have a relative Allow angular movement of the adjacent segment over a limited arc and relative arc movement over that arc also prevent the anchoring-unanchoring be ^ direction is designed so that all segments rotate simultaneously and thereby the stops in the end parts for engagement bring and that the adjacent segments perform a counter-rotation independently and so the stops to each pair of pusher part segments disengaged from their end parts in a predetermined time with respect to the longitudinal transfer of the pusher parts or bring bumpers. 709825/0890