NZ239048A

NZ239048A - Forming and filling flexible film pouches: sealed by ultrasonic energy

Info

Publication number: NZ239048A
Application number: NZ239048A
Authority: NZ
Inventors: Jean Marie Denis
Original assignee: Colgate Palmolive Co
Priority date: 1990-08-13
Filing date: 1991-07-19
Publication date: 1994-08-26
Also published as: AU649462B2; HU912681D0; RO112492B1; ITRM910607A0; DE4126557A1; HUT66006A; FR2665683A1; GR910100347A; CN1028625C; ZA915599B; IT1249437B; ES2052417B1; EG19261A; ES2052417A1; MY107958A; ITRM910607A1; FR2665683B1; JPH04253621A; AU8164991A; PT98653A

Description

<div class="application article clearfix" id="description"> 239048 Cc« i ij—.vi^J s_ , r*l r+ • 12$3!., r. r1 * 2 6 .AU 6 » 73*3. ULTRASONIC WELDING IN POUCH MANUFACTURE Patents Form No. 5 PATENTS ACT 1953 COMPLETE SPECIFICATION Number Dated // *•5?.— ' We, COLGATE-PALMOLIVE COMPANY, of 300 Park Avenue, New York, New York 10022, United States of America, a corporation organized under the laws of the State of Delaware, United States of America do hereby declare the invention for which I/we pray that a Patent may be granted to me/us, and the method by which it is to be performed, to be particularly described in and by the following statement: - 1 - (followed by page la) 239048 This invention relates to an apparatus and a method for the manufacture of filled pouches from films using ultrasonic welding. More particularly, this invention relates to the use of an ultrasonic sealing assembly to form pouches through the sealing of seams of films and also for cutting the films to form the individual pouches. There are various techniques that can be used to form pouches from films. Regardless of the technique, seals will have to be made. The flat film must be manipulated to provide both a front portion and a back portion. This can be done in many ways. One convenient way is to first form the film into a tube and then to form the tube into pouches. In this technique, there will be a longitudinal seam where the film is formed into a tube and end seals for the formation of the tube into a pouch. An advantage of the technique of forming the film into a tube, and then forming the tube into a pouch is that in the process of the formation of the tube into a pouch, the pouch can be filled. There are advantages to forming and filling the pouch in the same sequence. Films can be sealed to form pouches using various techniques. Adhesives can be used to form seals. A heated platen can be used to seal thermoplastic films. Dielectric heating, also known as radio frequency (RF) heating, can be used. However, the use of ultrasonic sealing has la 239048 'advantages over any of these techniques, and particularly in form/fill sequences. When adhesives are used, there are solvent removal problems. There are also required cure times. The use of a heated platen is not efficient since the film must be heated by conduction. In RF energy, heating the full thickness of the film is heated rather than the film surface. This provides good sealing but is restricted to films that absorb a sufficient amount of RF energy to soften. Also, since the full thickness of the film is heated, there is the potential for overheating the film and depositing pieces of film, known as flash, onto the electrodes. This will affect subsequent seals made by the electrodes until they are cleaned. It has been found that the use of ultrasonic sealing for forming pouches from thermoplastic films is an improvement over the use of adhesives, heated platens or RF energy. In ultrasonic sealing, only the surfaces that are to be bonded are heated. They are heated by absorbing impact energy. The full thickness of the film is not heated. This provides j for various advantages. Films that do not have a sufficiently high absorption for RF energy can be used to make the pouches. The problem of flash formation is also obviated. Due to the heat being formed only at the impact surfaces, flash will not be produced. It has also been found that the use of ultrasonic sealing has distinct advantages in form/fill operations. These are operations where the pouch is filled as it is formed. A problem with form/fill operations for pouches is that during the filling sequence, there is a tendency for the product to contact the area of the pouch that is to be sealed. In other types of sealing, including RF sealing, this can produce weakened seals. However, in ultrasonic sealing there is a cleaning of the surfaces that are to be bonded prior to bonding. This is accomplished by surface to surface vibration. Consequently, it has been found that the use of ultrasonic 2 2 sealing in form/fill operations has distinct advantages. It produces consistent high strength seals. Ultrasonic techniques have been used in bonding various materials. They have also been used in making bags and pouches. In U.S. Patent 4,734,142 there is disclosed a bag sealing machine which utilizes ultrasonic sealing. The bag that is produced would contain meat or produce. U.S. Patent 4,767,492 discloses the use of ultrasonic techniques for sealing tubular containers. These containers are sealed in a separate operation after filling. In U.S. Patent 4,866,914 there is disclosed an ultrasonic device for sealing pouches. A product is placed into the pouch and the pouch subsequently ultrasonically sealed in another operation. It is noted in this patent that any foreign substances adhering to the sealing surfaces will be removed during the sealing operation. These patents illustrate the state of-the-art of ultrasonic sealing pouches. However, none of these patents is directed to the use of ultrasonic sealing in a form/fill process. It is also known to use an ultrasonic horn an anvil to both seal and to cut a film. In U.S. Patent 3,939,033 there is disclosed a process where the stationary fixture has a first raised means for sealing and a second raised means for cutting. That is, the same surface does not do the sealing and the cutting. However, it has been found that the same surface can do both the sealing and the cutting. This results in a more efficient ultrasonic unit. BRIEF SUMMARY OF THE INVENTION It has been found to be advantageous in forming and filling thermoplastic pouches to use ultrasonic sealing techniques in forming the pouches. Ultrasonic sealing has advantages over the use of adhesives, conduction heating or dielectric heating. A distinct advantage is the 39048 3 239048 ability to simultaneously clean the surface of the film that is to be a part of the seal while heating this surface to at least its melting point. This is important in form/fill sequences where the pouch will be formed and filled in the same sequence. In such packaging operations, the substance being packaged, usually a liquid, will contaminate some of the seal area when it is flowed into the open pouch. In order to get a good seal, this area should be clean. This can be accomplished in various ways. However, the most efficient way is to use ultrasonic sealing techniques. In this way, the seal area will be cleaned as it is being sealed. Also a part of the present invention is the use of an ultrasonic sealing unit which is comprised of an ultrasonic horn and an anvil for the dual purpose of sealing a film and cutting a film. This is accomplished by the same surfaces on the ultrasonic horn and anvil. The shaped cutting surface will, preferably be a part of the anvil and will be of a triangular cross-sectional shape. The outside base angles of the triangle will be .j about 120° to 160°. This will provide for 20° to 60° interior angles. The top of the shape terminates in a smooth edge. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a rear elevational view of a pouch with a beak spout formed using ultrasonic techniques. Figure 2 is an elevational view of a sealing unit for sealing the longitudinal seam of the pouch of Figure 1. Figure 3 is a cross-sectional view of an anvil for sealing and severing a film. Figure 4 is a top plan view of the ultrasonic horn/anvil assembly for forming the top and bottom seals and beak spout of the pouch of Figure 1. Figure 5 is a cross-sectional view of the ultrasonic horn/anvil of Figure 4 along line 5-5. . ; , 4 23904 Figure 6 is an elevational view of the transverse ultrasonic horn and anv.il assembly. Figure 7 is an elevational view of the form/fill unit for forming and filling pouches. DETAILED DESCRIPTION OF THE INVENTION The present invention is directed to a process for the ultrasonic sealing of pouch containers during the process of filling the pouches as well as the use of the ultrasonic horn and anvil assembly as a means for both sealing and cutting the thermoplastic film. In this regard, the ultrasonic horn and/or anvil must be of a particular shape in order to provide for the dual functions of sealing a thermoplastic film and then severing the thermoplastic film in the region of the seal. In order to provide for both the ultrasonic sealing of thermoplastic film and the subsequent severing of the film at least one of the ultrasonic horn or the anvil will have to be shaped for the severing operation. It is possible to have both the ultrasonic horn and the anvil of the ultrasonic sealing unit shaped to effectuate severing. However, this is not necessary. Only the ultrasonic horn or the anvil needs to be shaped for cutting. In this regard, it is preferred to shape the anvil. This is the case since the shaped piece will have greater wear. It is preferred to have an accelerated wearing of the anvil rather than of the ultrasonic horn. % The present process will be described with reference to the manufacture of pouches having spouts. An illustrative pouch is set forth in Figure 1. This pouch is designated 10 and has a rear surface 11, longitudinal seal 12, a bottom seal 13 and a top seal 14. There is also a beak spout 15 with a cut-out 17 and associated seal 16. The rear pouch surface is designated. 5 239048 ' in the process of forming and filling the pouches of Figure 1, a film is in a first step formed into a tube which is accomplished by each edge of the film being overlapped from about 0.1 cm to 1.0 cm to form a seam. This seam is passed between the ultrasonic horn and an anvil of a longitudinal ultrasonic sealing unit. Since the seam is now between the ultrasonic horn and the anvil upon the application of pressure and ultrasonic energy to the ultrasonic horn and/or anvil the thermoplastic material at the seam juncture is heated and bonded. Pressure is preferably applied to the ultrasonic horn. After this step, the film is now in the shape of a tube. Preferably, at the same time that the side seam is being sealed, a pouch top seam is being formed and sealed on a lower pouch. Also preferably at this time the beak spout is being formed on this lower pouch and a bottom seal on yet a further lower pouch. This is the case since the film is in a stationary position and for increased efficiency more than one operation can be conducted on the film at this time. Thus a side seal, a top and beak seal and a bottom seal are all being made at once, although on different pouches. This top and beak spout seam are formed by means of a separate transverse ultrasonic sealing unit vis-a vis the side seal unit. This lower transverse ultrasonic sealing unit, will in a first step, place the interior surfaces of the tube into contact to form both the top closure seam and the beak spout seam, and thence through the application of pressure and ultrasonic energy will cause this pouch top seam to be bonded * and the beak spout to be formed by bonding the surfaces to this shape. This film is now in the form of an inverted pouch which is open at its upper end. At this point, it is now reader to be filled with a substance, usually a liquid. After filling, this filled pouch moves downwardly and the transverse ultrasonic sealing unit is activated for another cycle. The pouch bottom "seal is formed on this filled pouch in this next cycle. / 6 239048 Simultaneously the top seal is formed on the adjacent upper pouch along with a seal to form the beak spout. In each cycle after these seals are formed, the application of ultrasonic energy ceases and the pressure of the anvil against the ultrasonic horn is increased. In this way, the anvil and ultrasonic horn then function as a severing device to sever the film to form the beak spout on an upper pouch and to sever the now sealed and filled lower pouch from the upper pouch which has had the top seal formed but has not as yet been filled. In summary, the transverse ultrasonic energy sealing unit, at the same time as sealing the bottom seam of a filled lower tubular pouch will also, seal the top seam of an upper pouch and form the beak spout of this upper pouch. This step can be carried out concurrently with other sealing steps since the film is in a stationary position. In this way, in this form/fill sequence, three different sealing operations can be conducted during each interval when there is a pause in the flow of the film. The side seam is sealed to form a tube, the top seal and spout are made for a pouch for which the side seam has previously been made, and the bottom closure seal is made on a lower pouch which has just been filled with a substance. After the top seal and beak spout of the upper pouch and the bottom seal of the lower pouch have been formed, the ultrasonic energy is stopped and the pressure between the anvil and the ultrasonic horn is increased to thereby sever the lower filled pouch from the upper empty pouch. The lower filled * pouch is then forwarded for packing and the upper formed pouch is filled. Also in the above sequence as the transverse seals are being formed, the beak spout is being formed. A persistent problem with regard to these pouch containers is that of the contamination of the transverse sealing areas at the time that the pouch is being filled. This is a contamination by the contents that are 7 239048 being flowed into the pouch. This is caused by a splashing of the substance being flowed into the pouch and a dripping of the product upon the termination of the filling process. Since the inner thermoplastic surfaces are to be bonded, one to the other, an excessive contamination can affect the integrity of the transverse seals. However, since in ultrasonic sealing it is the film juncture that is being heated, rather than the full thickness of the thermoplastic film, there is a more effective weld sealing of the pouches using ultrasonic sealing rather than other techniques. This is the case since the ultrasonic energy' is focused on the inner juncture surfaces of the thermoplastic film and will quite efficiently remove any contaminating substances from these surfaces prior to seal formation. This is in contrast to radio frequency heating, also known as dielectric heating, where the full thickness of the thermoplastic film is heated. In dielectric heating there is not a concentration of the bonding energy only onto the thermoplastic junction surfaces. It is also not an energy which * assists in the cleaning of the bonding surfaces. The longitudinal sealing unit is shown in Figure 2. The ultrasonic horn 20 and the anvil 21 can each have a flat working surface. The surfaces will either both be smooth, or one surface can be textured and the other smooth. In use, surface 22 of the ultrasonic horn is in close proximity to the surface 23 of the anvil. The anvil can optionally be cooled by flowing water or other fluid through each unit. If necessary the ultrasonic horn can be cooled by a jet of air. In the present instance, each of the ultrasonic horn and the stationary fixture are designed to be cooled. In this regard, the anvil has inlet port 27 and exit port 28 for the flow of a cooling fluid. Although any of the usual frequencies of that are used for ultrasonic sealing can be used, it is preferred to use a frequency of about 10 KHz (kilohertz) to 70 KHz and most preferably about 8 239048 20 KHz to 40 KHz. Energy is supplied to the ultrasonic horn through booster 29. The longitudinal sealing unit is designed for sealing and need not be capable of also cutting film. However, when it is desired that this unit also be used for cutting, the anvil of ultrasonic horn would have a contact surface as shown in cross section in Figure 3. The angle A of the surface 30 is from about 120° to 160°, and preferably about 150° to 175°. This results broadly in an interior angle of 20° to 60°. The top surface 23(a) is an edge and is sufficient to produce an effective seal, but yet as the pressure between the ultrasonic horn and the anvil is increased, the film can be cut. In Figure 4, there is shown the anvil assembly for producing the top and bottom seals and the beak spout for the pouch of Figure 1. This unit simultaneously forms the bottom seal of a lower pouch and the top seal and the seals around the beak spout of an adjacent upper pouch. After these seals are formed, the pressure between the ultrasonic horn and anvil is increased, and the thermoplastic material between the bottom seal of one pouch and top seal of another pouch and the excess material in the area of the beak spout is severed. This ultrasonic sealing unit must have sufficient energy to complete the seal and to thin the material for subsequent severing of the thermoplastic film. The shape of the surfaces also produces a thinning of the film. An ultrasonic frequency of 10 KHz to 70 KHz is preferred, with a frequency of about 20 KHz to 40 KHz being most preferred. The unit shown in Figure 4 is the anvil assembly 40 of the transverse ultrasonic sealing unit. This unit consists of base support plate surface 41 which supports the top and bottom sealing anvil 42 and the beak spout sealing anvil 43. Each of these anvils is raised above the surface of the 239048 support plate to the same extent. The sealing anvil 42 has a surface 44 which contacts the corresponding ultrasonic horn surface and the anvil 43 has a surface 45 which contacts the corresponding ultrasonic horn surface. The base plate can be cooled by a fluid flowing through the plate via ports 46 and 47. The contact surfaces 44 and 45 are in the form of an edge and are effective to produce the desired seal and subsequently to cut the film. Consistent with the desired seal this surface will preferably be an edge. The shape of the anvils of this ultrasonic sealing unit is shown in more detail in Figure 5. The exterior angle A of anvil with the horizontal axis, which in Figure 5 is also the base plate, is about 120° to 160°, and preferably about 135° to 150°. This results in interior angles of about 20° to 60° and preferably about 70° to 45°. The anvils are shaped to produce effective sealing and effective severing of the film after sealing. During the sealing operation, the pressure between the anvil and ultrasonic horn, is about 10 kg/cm2 to 50 kg/cm2. This is increased to about 20 kg/cm2 to 100 kg/cm2 for severing the film. The increased pressure is dependent on the pressure that is utilized during the sealing operations-. The pressure can be increased by the anvil being moved against the ultrasonic horn or the ultrasonic horn being moved against the anvil. In Figure 6 there is shown the complete transverse ultrasonic sealing unit for forming the top and bottom pouch seals and the beak spout seals. % This consists of essentially the anvil assembly 40 and ultrasonic horn 35. This unit produces the top and bottom seals as well as the beak spout —• ^ seals. This ultrasonic horn consists of flat surfaces 36 to contact the shaped surfaces 44 and 45 of the anvil. The ultrasonic energy is transferred from the booster 37 to the horn. However as noted above, the ultrasonic horn can be shaped to function to sever the film rather than the 10 239048 anvil being shaped to serve this purpose. Either the ultrasonic horn or anvil must be shaped to provide for a severing of the film after sealing. If the ultrasonic horn is to function to sever the film, the contact portion 36 of the ultrasonic horn must be of the shape as is illustrated for the anvil. In such an instance the anvil will have a flat surface. The ultrasonic horns can be constructed of titanium, Monel alloys, aluminum or aluminum alloys. Titanium is an effective metal for ultrasonic horns. The anvil can be of the same or a different metal from that of the ultrasonic horn. The anvil can also be a stainless steel. The anvil should have a low wear rate. Figure 7 sets out a preferred form/fill apparatus. In this form/fill apparatus the pouch of Figure 1 is formed and filled in a top side ''down arrangement. That is, the beak spout and top seal are formed first in the lower portion of the tube, the partially formed pouch filled, and the bottom seal then formed. This arrangement is needed for the » H formation of a pouch with a beak seal since the pouch must be filled after the beak is formed. The film 51 is unwound from supply roll 50. This passes down over tension roller 52 and over directional rollers 53 and 54. The film then passes over roller 56 and downward to the form/fill section. At 57, the film is formed into an open tubular shape. Shaper 57 is supported by fill conduit 59 which receives a product to be packaged, usually a liquid product from supply conduit 58. The film passes in an * open fashion by supply conduit 58 to the seam forming and longitudinal sealing section 60. In this sealing section, guide 61 directs the film into a shape so that there is an overlapping longitudinal seam for sealing by the longitudinal ultrasonic sealing unit. The longitudinal ultrasonic horn 63 receives ultrasonic energy from transducer 62. The anvil is 11 239048 carried by fill conduit 59. The film, now in a tubular form, exits longitudinal sealing section 60 and is moved downwardly by controller 64. Controller 64 moves the film intermittently and stops film flow in order to permit the sealing, cutting and filling operations. This controller includes drive rollers 65 which move the film. In the region below the controller, the tube is transversely sealed at 67. This is accomplished by the lower sealing unit as illustrated in Figures 4, 5, and 6. This lower sealing unit will form the top seal and the beak spout on the tube to form an open ended pouch. This pouch is in an inverted arrangement.Simultaneously, a lower pouch that has been filled receives a bottom seal. This all occurs at a first pressure between the ultrasonic horn and the anvil and the application of ultrasonic energy. At a second higher pressure of the ultrasonic horn against the anvil, and without the application of ultrasonic energy, the film is cut to separate the lower pouch and to cut the film to form the beak spout on the upper pouch. In this sequence, after the top seal and beak spout are formed, a pouch is filled from spout 66 of fill tube 59. After the filling step, the filled pouch moves downwardly and the transverse ultrasonic sealing unit goes through another cycle of making the bottom seal of this pouch and the top seal and beak of another pouch. As has been noted, the flow of the film is intermittent. The flow of film is stopped for the sealing operations and for pouch filling. Thus, each time that the film flow stops, longitudinal ultrasonic sealing unit 63 is actuated as is transverse ultrasonic sealing unit 67. Also, while the film flow has stopped, the pouch that has been formed is filled. Essentially any film which can be welded by means of ultrasonic energy can be utilized to form the present pouches. The particular thermoplastic films can be either amorphous or crystalline. Suitable films include those 12 239048 'of acrylic copdymers, cells, cellulosic, phenylene oxide, polycarbonate, and polystyrene. Generally, crystalline resins are not as easily sealed using ultrasonic techniques as amorphous resins. Crystalline films are more rigid. Flexible films are preferred. However, acetal resins, fluoropolymer resins, nylon resins and polyester resins can be utilized in ultrasonic sealing techniques. A preferred film is one which contains at least one layer of ethylene-vinyl acetate. The other layer or layers can be a polyolefin such as polyethylene, polypropylene, polybutylene and polybutadiene. The pouches which can be formed using the present ultrasonic sealing techniques can be of essentially any size. However, the preferred sizes range from about 50 cc. to about 2 liters in size. These are the sizes that are conveniently handled with regard to this type of packaging technique. The substances which are packaged within such pouches include personal care products, household care products and foods. In the category of personal care products, there are liquid soaps, shampoos, and lotions. In the household care area, there are cleaning and polishing compositions, fabric bleach compositions, and general purpose soap compositions. In the food area, there are included various sauces, gravies, fruit flavorings and the like. EXAMPLE 1 This example illustrates the forming and filling of pouches using the * form/fill apparatus of Figure 7. A polyethylene/ethylene - vinyl acetate coextruded film 51 having a thickness of 0.20 mm and a width of 16 cm^is fed from supply roll 50 to a pouch forming and filling machine via rollers 52, 53, 54, and 56. The film is fed in a continuous strand 51 to a form/fill machine. As the film passes through an upper shaper die 57, it is formed into a tubular shape .13 239048 with an overlapping longitudinal seam. The film overlaps about 10 mm. The film passes between a longitudinal ultrasonic horn 63 and stationary fixture. The impinging pressure is about 40 kg/sq. cm. The flow of film ceases momentarily during this operation. The side seam is formed by .the film edges being held between the longitudinal ultrasonic horn and the anvil (as shown in Figure 2) and an ultrasonic energy at a frequency of 20K Hz applied. At the same time, transverse bottom seals are being formed at the lower portion of the tube as is a beak spout. This is formed by a transverse ultrasonic horn and mobile anvil assembly 67 (as shown'in Figures 4 to 6). At the same time that the top seal and beak spout are formed on this pouch, a bottom seal is being formed on a lower pouch which has been filled. An ultrasonic frequency of 35 KHz. is used to form these seals. The impinging pressure of the transverse ultrasonic horn and anvil assembly during sealing is about 40 kg/sq. cm. After the side and top seals along with beak spout are formed .on the present pouch, the newly I formed pouch with an open bottom is filled with 250 cc of bleach. The lower pouch which has undergone closure sealing has been severed and is conveyed to packing. The severing is accomplished by increasing the impinging pressure of the ultrasonic horn against the stationary fixture to about 90 kg/sq. cm. No ultrasonic energy is applied at this time. This then completes a machine cycle. This cycle is then repeated. The sealed seams of a representative number of pouches are tested in a pressure tester. The pressure tester has a stationary and a moveable platen. A sample is placed between the platens and the pressure on the pouch increased. A burst strength of greater than 150 kg indicates an acceptable filled pouch. The pouches consistently exceed 150 kg. 14 </div>

Claims

<div class="application article clearfix printTableText" id="claims"> 239048 WHAT WE CLAIM IS:

1. A method of forming a shaped, sealed flexible film pouch containing a liquid substance comprising partially forming a flexible film into a pouch using ultrasonic energy, substantially filling said partially formed pouch with said liquid substance, closing said pouch by sealing the opening through which the pouch has been filled using ultrasonic energy applied by an ultrasonic horn to an anvil at first contact pressure, and increasing the contact pressure to sever the film.

2. A method as in claim 1 comprising: (a) shaping said flexible film into a tubular shape with an overlapping edge; (b) bonding the overlapping edge of said flexible film to said flexible film with ultrasonic energy to form a tube; (c) sealing by ultrasonic energy a lower portion of said tube to form a first pouch; (d) filling said first pouch with said substance; and (e) sealing by ultrasonic energy (I) an upper portion of said first pouch to seal said pouch, and (II) another lower portion of said tube to form a second pouch, and severing said first pouch from said second pouch.

3. A method as in claim 2 wherein a die shapes said film into said tubular shape having an overlapping edge of substantially 0.1 cm to substantially 1.0 cm.

4. A method as in claim 2 wherein said overlapping edge is bonded to said flexible film with an ultrasonic horn and anvil at a pressure of between substantially 10 kg/cm2 and 239048

5. A method as in claim 2 wherein said sealing steps (c) and (e) (i) and (ii) use a ultrasonic horn and anvil at a pressure of between substantially 10 kg/cm2 and substantially 70 kg/cm2 and an ultrasonic energy having a frequency of substantially 10 KHz to 50 KHz and the first pouch is severed from the second pouch by an increase in the pressure between said ultrasonic horn and anvil of between substantially 20 kg/cm2 to substantially 100 kg/cm2 in the area of the seals that have been formed.

6. A method as in claim 2 wherein said flexible film has at least one ply that is bondable to itself by means of ultrasonic energy.

7. A method as in claim 6 wherein said flexible film has at least one polyene layer and an ethylene - vinyl acetate layer.

8. A method as in claim 7 wherein said polyene layer is selected from the group consisting of polyethylene, polypropylene, polybutylene and polybutadiene.

9. A method as in claim 2 wherein said flexible film is fed as a continuous sheet, formed into a continuous tubular shape and sealed to form a continuous tube.

10. A method as in claim 2 wherein said flexible film is in a stationary position when said upper portion and lower portion are sealed and said first pouch severed from said second pouch.

11. A method as in Claim 2 wherein in the sealing of the upper portion, abeak^spout i§ formed and the excess film adjacent the beak spout is severed in a further step. t* n;\27 JUNM4 *1 \As coJ 16 2390

12. A shaped sealed flexible film pouch produced by the method of any one of claims 1 to 11 containing a liquid substance comprised of one or more plies, having a side seam, a lower seam, an upper seam, and a spout, all sealed through the use of ultrasonic energy.

13. A shaped sealed flexible film pouch as in claim 12 wherein said spout is at the upper edge of said pouch and is in the form of a beak.

14. An apparatus for forming and filling pouches comprising; (a) means to shape a flexible film into a tube having an ( overlapping longitudinal seam; (b) a first ultrasonic horn and anvil assembly; (c) means to position the overlapping longitudinal seam of said flexible film between said first ultrasonic horn and anvil; (d) means to actuate said first ultrasonic horn and anvil assembly to seal said overlapping seam to form a tube; (e) a second ultrasonic horn and anvil assembly located subsequent to said first ultrasonic horn and anvil to form top and bottom closures on said tube and produce a pouch; (f) means to actuate said second ultrasonic horn and anvil assembly at a first contact pressure to seal said top and bottom closures and at a second contact pressure to sever the film that has been sealed to separate a filled pouch from said tube; and (g) filling means subsequent to forming said bottom closure and prior to forming said top closure to substantially fill said pouch.

15. An apparatus as in Claim 14 compising means to produce a contact pressure between said first ultrasonic horn and stationary fixture of substantially 10 kg/cm2 to 70 kg/cm2.

16. An apparatus as in Claim 14 wherein said second ultrasonic m@xn fa and anvil assembly is comprised of an anvil having a raised cutting lljj surface. 17 239048

17. An apparatus as in Claim 16 wherein said raised cutting surface has a base exterior angle of substantially 120° to 160°.

18. An apparatus as in Claim 14 wherein said second stationary fixture has a surface adapted to cut a film after sealing.

19. apparatus as in Claim 18 ccrnprising means to produce a pressure of substantially 10 kg/ cm2 to 70 kg/ cm2 between said second ultrasonic horn and anvil during sealing and a pressure of substantially 20 kg/ cm to 100 kg/cm2 during severing.

20. An ultrasonic horn and anvil assembly for sealing and severing thermoplastic film comprising a shaped contact surface on one of said ultrasonic horn or anvil adapted to seal said film upon the application of a first pressure and ultrasonic energy and to sever said film upon the application of a second higher pressure.

21. An ultrasonic horn and anvil assembly as in Claim 20 wherein said shaped contact surface is essentially triangular in cross-section with the base exterior angle being substantially 120° to 160°.

22. A method of forming a shaped sealed flexible film pouch substantially as herein described and with particular reference to the drawings.

23. An apparatus for forming and filling pouches substantially as herein described with particular reference to Example 1 and Figure 7.

24. a shaped sealed flexible pouch when produced by the method of any one of claims 1 to 11. WEST-WA'LKER, McCABE ATTORNEYS pen 27 JUK1994 18 i </div>