CA2148284A1 - Method for manufacturing a film, a bag made from a film, such a film - Google Patents

Abstract

A bag (1) which is produced from a substantially endless film (37) which is formed, while filling in goods, into closed individual bags (1) provided with an overlapping joint (11). The overlapping joint (11) consists of two overlapping edge areas (13, 15) between which an adhesive (25) is applied which is sensitive to pressure. The overlapping edge areas may be separated and reclosed so that a partial emptying of the bag is possible followed by airtight reclosure of the overlapping joint. The bag is particularly well suited for use in packing machines of the so-called VFFS type.

Description

.~ C, .~ nr ~ ~, L~ t ~ IU-- tt~ ~ ~t~t~
~ 2 1 ~ 8 2 8 4 REPlACcMENT SHc~T
^. t~i METH013 FOR MA.~ F.~.Cl'U~UNG A FEL.~, A B~G ~I~DE FROM A
FlL~, SUCH A ~}1 M, AND ~HE USE O~ T~IE FII

~AC~CG~OU~TI; OF THE l~''E;~IC)~.
.. S The presenl invemion r~la~ o a me~hod tar rn~nutacr~ing a fi]rn ;o be us~d for ~he produclion o~ ~a~s ~hich, during a product nlling pr~ur~ are fiormed int3 clos~i in~l~id~l ~ags whe~ein a c~ntinuous and subs~tially endless nlm is m~nur~cNr~, which film is rut up longimdinally, wherein the tw~ l~r~,l ~reas adja~ut t~ the ru~ are put inu~ an s~er!aoping position, wtle~ein betwe~n 10 che r~o over~appino s~ facing each o~er an adhesive is applied ~hlc;~ ~
s~nsir~ve ~o pressur~ and a~le tc glu~ several ~imes, and wher~in ~.e overlapping - l~eral are~s ~re put into ~n~cl with hle adhEsive applie~ be~we~n he~.

The i.,n~fenbion also r~lates to a ba~, produ~d from a subs~n~i~lly endless tilm13 which, during a produc~ fillin~ procedure. is -.orrne~ im~ c'~d inahvidual bags.
wherain ~we~n ~wo closw ends he ba~, has ~n o~,erla~pi~g joinr whic:l ex-~n~s pa~ l ~ a longimdina~ welding o~ ~he f~im's la~ral ~ges ~hich we!ding has ~e~n made wh~n f~r;ning ~e closed irldividua~ bag. and ~ sur~s fa~ing ea~h o~her in ~ne overlapping j~int are pr~vided with an adhæsi~ e of a know~
~Q ~ype which is a~le ~o ~lue several ~imes.

llle invennon also r~lau~s to the ~llm for dle p~duction of a ba~ rding to the in~entian, wher~in in a po~ition ~e~een Ihe film's laseral edges a~ leas~ one overlapping i~in~ is provid~d wherein - betwe~ two o~er1apping sur~aces f~ing h other - an adh~i~ve ha~ bx~ proYided which is or a l~nown type an~ abie uo ~lue ~cYeral times.

lt is well lcnown ~o produc: bags. ~enerally ~ be c~nsidered as a sales pac~a-gin~ and pr~duced from fla~ fflm webs which arc produced in a single layer or 30 in a nlbular shapc. S-u:h bags are prirnarily p~oduc~d fr~m resin ma~ria~s inwhich a clo~ure is ob~:ained by weldings lengthwise and crosswise on ~he f~lm.
Howevçr, th~ invention als~ relate:i ~ b2~s p~duced rrom o~er mar~ri~is in~luding webs of technical ~extiles, papers, anà o~hers.

~ME~IDED SHEET

K~ t~ t~ 94 ~ 3 " ~ +~9 8Y ';3~194~
~ 2 1 4 8 2 ~ ~ REFLACM~IJT S~tE~r I

1~ prior ar~ bags which ar~ formed into c'osed individual bags du~ng ~he fil]ing process will be close~ perm~nently~ Th~s me~ ~ha~ the bag musl be cut o~ ~rn open in o~der to use its cl~nc~n~ only part of ~he c~n~ents is ~Is~d. theopening mus~ be reclosed tempo~arii-. l~.is may ~e a~c~mplishea in Yarious S ~. e~o. ~y ~he us~ or clips, ban~s or by folding. rhis m~y be undesir~ble if the ~o~ds eon~ained in the ba~ are ~xpo~d t~ de~rio~alion due ~ improper or insur~lent r~-iosing. ~lore~ver. an imprope. or insuf~lci~nl r~s:losure n~y imply ~ hat the o~ds will fall oul o~ ~e bag during subse~uen~ slorage.

lû rne oo~ds c~n~ined ~n ~.e 1~2g ala~/ be o~ manv kinds. llley may be ~oods~
such a~ chips, c~ffe~ flour, oa~s or odlers. They may a~so be any kinci o~ ~ain - ma~rlal ~uch ~i corn, gra~e~ or oT~er~. rne goads w~ llet intçl ~he bags ma~ als~ have a fillly or partial!y liquid subslance~ ~s known e.g. rrom k~nup.
rnu~d~ ~yoMaise and othe~s.
1~

AME~DE.,~ St!EET

~C~ FP.'~ 1.\ ~) L ~ L~ ' L~ 94~
~ 214828~
- nrrLACch~EN~ ShEET

Hilhcrt~, ~ne c~nsumers ~aYe had ~he disadvantage of insuffcient rec~osure.
Such disa~Yan~ges haYe so ~r bee~ insunnour~c3ble u~less on~ would usc bags special re~osa~le arrangcrrlen~s, e.g. zip s~ r ad`~esiYC sysGems. H~
wever, such spe~i~ rec!o~able arrangemems G~Lo~ be used in pr~c~sses where S a f:ilrn is used .or ~e produc~ion ;)T bags which are rorTned in~o closcd individ ~s ~urtng Ihe fiiling of ,ooods.

FurLhermore, zip sys~ms ~ill b~ partic~rly disadvantage~us ror use in a m;~s pr~duction. Owing ~ Ihe considerable ~h.cxness of a zip co~par~i ~o a film. it !0 would inv~ big dif~lc.ul~ies to use a nlm provided wi~ zips when -.he film isu~ be c~ndu~ted ~rou~h ~a~hines by rollers~ Fur.hermore~ it woulld be ve:y di~ficul~ s~ har.dle fi~m with 2ips on rolls because of its po~}r rollin~ ge~m~.
It ~s known~ e.g. firom the DE-.~-3 835 7'~1 ana rhe ~ur~ n Pau~ Appliczl on ~o. 0.032.006. ~ prod~ bags i~ which an ~dhesive is pr~vide~ be~ween ove,~appir~g par~s ol a ~:ilm. Howe~rer, th~ tl~m an~ the ~ag ac~rding ~ ~e pnor art are produoe~ ~ indi~,du~l bags~ wl~out the fiiling of ao~as. The fiiling of ~oods is a~omp~ished during a subse~uent handlin~ o~ .he irldividu~i bags~ This is disa~Yan~e~ r a broad ra~gc~ or g~ods sinc~ it is desirabie ~o em inco baga while ~he bag ~ being formed. I'he bags a~ordin,~ ~o ~nc German public~ion would giYe a poor rollin~ g~me~ and ~er~ would exis~
pro~lems with the r~gisrratiun of bags in rela~ion ~ Lhe fillin~ ~quipmen~

Al~ough a ba~ accl)rding u~ dle ~ pean P~tenE Applica~ion pro~rides ~ oili-~5 ~y ~ be re los~ in a rela~ively ~igh2 and s~te w~y af~er par~al emp~ying of the bag'~ c~n~nts. this ba~ v~ould be unsui~able .:or c~mml~n ~llin, ~hir.~ of ~e so~alled VFFS ~ype (~er~ l Fil~ing, Fo~ning~ Sea~ing~. The G~rman bags r~ay be wed ir~ YFFS-m~hines, howe~ e wou~d be proble.ns with ~e r~losabili~y and the adop~ion of adhesivc u~ thc st:rength of pe~rOra~iQn lines. 3~
1~ ~s the ob~ecs af ~e prcs~nt invcntion to renx~y the ab~ve-;nenuoncd disad-van:ages of the prio~ ~ by dLsclosing a me~hod for D~nu~ uring ~ ~lim ~ be used i~ ~e produu:tion ~f bag~. as well as ~gs which, whil~ being praduc~d, A
1 . AME~IDED SHEET

~C~ ( Hk\~ l '-9~ '' '!o-- ~9 89 `';3~)4~
21 4 8 2 8 4 .~ cM~NT SH~ET
~ A ~ ~ G~..,. ~3S
are ~orme~i imo closed indi~ldual ba~s ~nd which m y, duri;lg subsEquem use, be reclo~d and reopen~ for pareial ~mp~ying of rhe bag s c~n~en~.

Ac~o~ding r,o .he pr~sent invention this is achi~e~ ~ a ~e~d ot ~he aboYe-.

!
.' .

i ."i .~ j .

i ~i ..~.
, si X__............... . .. . . .

`- RC`~ .\CHE.~_~? I_ : " L`'-~'~ a~ Lo~ `>-~Y~ f~
~ 21 4 8 2 8 4 RC~LACEMElYT SHEET
3 7 ~ 9 ;nentioned ~ype ~hich is characteri~d in ~a~ ~he cu~ ,c a straigh. cul ext~ndingparalle! with slde edges of Ihe Pllm, and rnal said cul~ provides a~ one of the s~de ~dges delimiting arL wening of ~he ba~, and thac Ihe o~erlapping lateral areaS arr~ ?osi~ion~d near on~ of the la~r~l ~dges of r~he film.

.~ r~im which i5 manutacrur~d in ~his m~nner ~s fi~ e hanaied i~. p~ckin~
machines ha~ing rollers. FurLhermofe, ~he film may be sro~e2 in roll~ e varialior.S is~ ulickn~s 3cro~s the width ot ~;e fil~n ~s insigninc;~rlt. The me~h~d is fi~her adYanE~ge~us in tha; ~lle .lirn ma~ ~e designed in 5Ur h 1 manner as 1~ ~rovid~, in the fini~ne~ ~ag, ~arety ~in~l unimend~ cess to r~ baz's con-out ~his '3ein~ noti~le. This is ~chieYed in ~hat in one la~er~l a.re2and parallel ~o ~he ~ut a !ine or we~k~ning is to~med, pre.~erably a p~ orati~n~
~ha~ in ~h oYer!appin~ po~ition this la~ ar~a is plac~d in suc~ a m2Dn~ ~hat i~ will mrn ou~ward in the ~inished ~ao, and uha~ ~he overlapping lat~
1~ are sealed by a iongir~dinally ex~ending we!~ding in a posi~i~n b~we~n u~c per-foralion ~nd ~e o~nos; ~ge ~f s~id lateral are~ in which said ?ero~ation ~as ~e~n maid.

Whe~ the film is us~d for rhe man~ ure o~ a~ag, said bag will ha~e a line o~
2û weakenin~ which ~ust be broken be~re u~e two overl~ppirlg la~era~ aras ean be separa~d ~^or a~c~ss ~ Ihe is~s~de of ~he ~ag Thus, uninunde~ aceess ~o ~he inside of :he bag is pre~en~d. which is tJery d~irable. e g. for ba~
sales pa~kaging in resailing.

75 It is pos~ibie ~ produc~ the tllm by pr~viding the r-ut ~nd the line OT ~e~ning sim.ult&ne~us1v with forming the t~lm. .~lu.~atiYel~. uhis rnay De accomplished in ~wo su~s~quenl sleps. It is also possible ~o apply an adhesive simult~ ly ~ith pro~iding ~e cut and the line of weakening. ~ ively, ~hese threc ~ps ma~ also be a~c~mpli~hcd 5~^pa~ately. The a~hesivc may be a~plie~ in a 30 s~ip in the 'ongi~udinal dire~ion Ot tho f~lm sim~ usly with providing ~he ~ RC~ L~C~tE~ -9~ L ~ , L,~ 9 8~ ~:3~34~
~ 2 1 4 8 2 8 ~ ~GE~E~Jr S~

cut. Subs~quen~ly~ la~ral afe~S are pul in~o an o~rlapping posi~ion and bro~lght into ContaC2 with ~ach other.

Il is ns:rrnally pref~ d ~ha~ ~e a~esive ;s appi ed ;n a sep~rale s~p prior ~o ormlng ~he cu~ and the line or we~kening Thus, it is preferred that ~.~ adhesi-~e ~ applie~l in a tlrst s~?~ in which ~he ba~ is alsa provide~ w.th a p~lnt on ~he ba~ ~s thi9 is acc~mplish~d a~ a ~d ot convey~nc~ ,;or ~Le film wnich is ver~
hi~h.

k will a~so be pre~er~ utLe line o~ we~kcn~ng or ~he s~te~ ?erfor3tion i~
;he bag is n~Lde simukane~uslv wilh r.~ing u~.e eul whæ~as sealing ~he cwo ~verl~pp~ng ~ s i5 Ollly pe.~ormed in immedia~e conn~c~ion with ~he tilling . ~he bag. ~n ihiS manner one ob~ains ~he leas~ v~tion ir. ;hickness ~best roilin~
8e~me~) across ~e wi~th or ~he wound tilm.

F~rmin~ the film. .~ay be ~er~ormed in a se?ara~e ma~hin~ in which the ~inished film i~ wound and in wnich ~he r~suk~ng roll is s~lbse~,ue~ltiy used in a packin~
m~hine. Alsernari~feiy, the produc~on of the nlm with overl3~pinJ se~ 2y be pertormed in immedi~ Mec.ion with ~ pa,~in~ machine ~.~elf.
;, ~ 0 The bag a~rding to d~e inven~ion is cllarac~e~i~ed in that ~he openin~ of the bag is delimited at 1~ by one of ~he side edg~s made wnen cu~ing ~he tllm and ~hat the o~er'a~ping join~ is positione~ n~ar one la~ e oi the ~a~
-~ ex~ing be~ n ~he two closed ends.
~5 .i In ~he bag, a re~losab!e openin_ ~s p~ov~d~d in the sales ~cing. This o,~e~ing may be ~ecured aga~ns~ unimended marlipuladon Ot ~e con~enoe if a line of wea-kening, preferably a perforauon, Ls providcd in ~e ~verlapping jaint, and ir ~he.. ~wo overla~ping laleral area~ are welded in ~ postlion ber~ he line Ot Wea-~0 kening ~nd ~he ou~cr cdge o~ th~ oun~ard la~eral area in the ~ag.
~, '''I

~2 ~lc~l~ED SHEET
.,,~

RC~ . `, 0~ C`H~ O I ~ 34 : L ;~ ` L l~-- -r~ 3S~

2 1 4 ~3 2 8 4 ? r~ ENT S~i -ET
c ; l r A~ the overlapping j~ , a c~osur~ is provided which LS sufficiently ~igh~ e used for fcods whe~e ~ani~ry au~orities require air,ight packa~ing. lhe c~nsu-mer m~y open ~he pack~ing a~ ~he o~erlapping joirll~ possiblv ar~ fir~l havin~
brokerl the Line o~ weakcning, and e~p~y ~he ~ag o~ the desired amounr. ~r g~
5 ods. Therear~e., the pa~ging m~y be re~'osed at ~h~ overiaPpiIIg ~,oin~.

k i~ preferred for â bag tha~ is ~ormed by provi~ing a welding ~t the r~o op-posed fr~ e~ges of ~ lm in a wPIding se;~n thal ~he o~er~a~ping join~ ~nds parallel with the join~ of the ~wo o~pased ~ves o~ the nlIn ~nd parall~i wich ~he 10 side edge ot` ~he ~ e cwo side edges of the filrn will ordin~rilv ~e jained ~hlough wel~ing. Whe~ ~he over~apping ~e~i ~s in a position immediately :lex; .oa side edge o~ the bag. s~id si~e e~ge o~ the 'oa, may subscquencly be s~:n as ba~ ~op by ~he ~nsume~. lhis i~ achieve~ ugh ~ fa~ ~hat ;he rec!osabie ope;ling of the bag will be ~irLLated a~ o~le end ot .he packaging~ which also 15 facili~s empcying the pa~ ing o~ i~ con~en~s~

The film ror use in ~he manufac~ of a bag a~rding ~o ~he invention is ~h~-.: racterized in ~t ~he overlapping join2 is arranged near one of the latera~ edg2s or ~e film. rhe film may easily be us~ inqc~nne~ion wi~h e~is~ing pac~ing ~0 m~hi~s fo~ ~he manufa~D~re of Ihe bag, since the vari~lion in mic.k:ness across ~e t21m does no~ pre~nt the ~Ise of the ~l]m in exis~tng pactcin~ m~c~ines. 1 hetllm is parucularLy wcll sui~d tor use in pa~cing machines ot the VF}~S type.

Th~ with ~he film a~cording ~o ~he in~en~ion it is possible GO manufac~re ba~
in e~a~dy ~he same mann~r as in ~he ~ ing me~ods ot ~he prior arc withou~
impor~ant inves~ments in 9pCCi~ ma~ines tor the manu~ac~ure of ~he b~gs l~he manufac~r~ of thP film is ~ery simple and ~ubse4uent llse of the film tor e manuf~mre of ba~s which a~ ~ormed du~in~ filling ~ easily accompl~s~
Thus, a rllm i~ produced which is wider than the in~nded nlm for use in ~c .

,.

;,~ A~,~l',`lO'iJ S~Er~T
' ~ _62 1 ~ 8 2 8 4 1, manufacture of the bag. The film is produced with an excessive width corre-sponding to the width of the overlap and so the film may be used directly in an existing packing machine.

The invention will now be further explained with reference to the accompanying drawing, wherein fig. 1 shows a bag according to the invention, 10 fig. 2 shows a sectional view through the bag according to fig. 1, fig. 3 shows a fragmentary picture of a film according to the invention.
- after application of adhesive but prior to formation of the overlap-ping joint, fig. 4 shows a fragmentary picture of the film shown in fig 3, after for-mation of the overlapping joint, fig. 5 a sectional view along the line V-V in fig. 4, figs. 6-8 show pictures corresponding to figs. 3-5 through a second embodi-~- ment of the film according to the invention, and fig. 9 shows a schematic picture intended tojllustrate the production of a f ~0 bag according to the invention with the use of a film according to the invention.

A bag 1 for foods, e.g. deep-frozen goods, may be designed as shown in figs. l f and 2. The bag 1 is produced from polyethylene filni extruded in a single layer.
f 25 whereupon the film is assembled and welded in a first welding seam 3 and subsequently in a second t~ansversal welding seam 5, whereupon the bag shape has been formed. After the filling of the contents 7, the bag is closed by a third welding seam 9. Alternatively, the film may be co-extruded or laminated from several layers, which may be in different materials. This may in particular be advantageous for bags in which rigidity in the bag sides is required at the same;l time as good welding qualities.

In the bag according to the invention there is an overlapping joint 11 consisting ,~
:i r 9979 21~t~28~ PCI/D1~93/0034s of a first edge area 13, which is the outer edge area and situated on top of anot-her edge area 15. The surfaces of the edge areas 13 and 15 which face each other are held together by an adhesive with a relatively weak adhesive capacity and which will not dry. The adhesi~e further has the quality that the surfaces 5 facing each other may be separated and reclosed.

The overlapping joint 11 extends in the whole of one dimension of the packa-ging 1, as indicated by a dotted line in fig. 1. In the embodiment shown, the ~elding seams 5 and 9 ensure that an opening may only be formed between the 10 seams 5, 9. However, an embodiment in which the welding seams perrnit ope-ning the joint 11 in the whole of one dimension of the bag may be produced.
-When buying goods in bags, such as indicated by the numeral 1, the consumer may manually separate the edge areas 13 and 15, take out the desired amount of lS the goods 7 and then reclose the joint 11 by pressing the edge areas 13 and 15 together. The closing method used also ensures that the bag may be reclosed airtight after taking out the goods.

A preferred embodimP-nt of the film according to the invention is manufactured after extrusion as a film in one layer, e.g. of polyethylene. The film will nor-mally be exposed to graphic treatment in which colours and writing are printed on the film, e.g. as shown in the demarcated fields 21 and 23. The fields 21, 23may for example form a coherent text on the package. Simultaneously with the ~ ~ printing, the adhesive is applied in a longitudinal strip 25 and parallel with the Aj 25 lateral edges 17, 19. Subsequently the film is cut transversel~. e.g. at the posi-tion indicated by arrows 27. Simultaneously with the cutting, the narrowest~
cutoff part of the film is led over the strip 25 so that the graphic print in the fields 21 and 23 fit together in a marked position~ cf. fig. 4. In this manner~ a ~t longitudinal overlapping joint l l is formed in the length of the film. Then the bag l may be produced in the ordinary manner, i.e. first joining the frec edges d 17, 19 and producing a first welding seam 3, etc.
., Figs. t~8 correspond to figs 3-5 but illustrate a second embodiment of bag The ~j W0 94/oss79 2 l 4 ~ 2 8 ~ pcr/DK93/oo3~ l parts that are identical in the two embodiments are designated with the same re-ference numerals and will not be further explained. The bag shown in figs 6-8 differs in that in the overlapping joint a line of weakening is provided in the form of a perforation 29. The perforation 29 is preferably provided simultane-ously with cutting the film 27. The perforation 29 is provided in the edge area which faces outward in the finished bag l. Thé two overlapping edge areas 13, 15 are welded together at 31. The weldi~g~3i extends in a position between the perforation 29 and the outer edge 33 of the edge area 13 in which the perfora-tion is provided and which faces outward in the finished bag.
The welding 31 is formed in immediate connection with the filling of the bag.
As the welding 31 will result in a variation in thickness, it iS not desirable in the film which is wound into a roll thal serves to supply a packing machine. The variation in thickness which occurs in the overlapping joint 11 will, however, not result in difficulties in handling the film in traditional packing machines.
The bag 1 which is produced from the film shown in figs 6-8 will prevent unin-tended access to the inside of the bag without this being noticeable. Thus~ in order to get access to the inside of the bag, it is necessary to break the perfora-tion 29 and separate the overlapping edge areas 13, 15.

Fig. 9 shows schematically the production of a bag according to the invention ina VFFS packing machine. The packing machine itself is illustrated by a filling pipe 35 through which material is filled into the bags l~ which are formed by advancing the film 37 in the direction of arrows 39. The film 37 is led around the filling pipe 35 and folded in a known manner around the pipe, as indicated at 41. Simultaneously with the filling, the`longitudinal welding seam 3 and the transverse welding seams 5 and 9 are provided. The film 37 is supplied to the packing machine from a supply roll 43 which has a rolling geometry that per-mits handling in traditional packing machines. The film shown in fig. 9 corre-:~ sponds to the one shown in figs. 3-5. Alternatively, a film 37 with a perforation ~ 29 may be used, as shown in figs. 6-8. In the latter case, the welding 31 is pro-'7~ vided at a position marked by an arrow 45. During production the film 37 is ,~

!: i 214 8 2 8 4 PCr/DK93/00349 ~:
9 .

advanced in a manner known per se synchronously with welding jaws which form the transverse welding seams S and 9 having mutual intervals 47. This production will be well-known to those skilled in the art and accordingly will not be explained further.
s Alternative embodiments of the film according to the invention are possible.
Thus, the film may be produced as a tube of film, where an overlapping joint in longitudinal direction is provided by applying adhesive, cutting and joining, inprinciple as indicated above. The subsequent production of the bag with a tube-10 shaped film may be done as with the plane film, leaving out the first weldingseam 3 as unnecessary. Furthermore, it would be possible to apply a strip of ad-hesive across the film whereupon the overlapping joint is formed by cutting and joining.

.

!

.
..~

¦
~I i

Claims (9)

C L A I M S.

1. A method for manufacturing a film (37) to be used for the production of bags(1) which, during a filling procedure, are formed into closed individual bags (1), wherein a continuous and substantially endless film is manufactured, which film is cut up (at 27) longitudinally, wherein the two lateral area (13, 15) adjacent to the cut are put into an overlapping position, wherein between the two overlapping surfaces facing each other an adhesive (at 25) is applied which is sensitive to pressure and able to glue several times, and wherein the over-lapping lateral areas (13, 15) are put into contact with the adhesive (at 25) applied between them, c h a r a c t e r i z e d in that the cut is a straight cut extending parallel with side edges (17, 19) of the film, and that said cut pro-vides at least one of the side edges delimiting an opening of the bag, and that the overlapping lateral area (13, 15) are positioned near one of the lateral edges (17, 19) of the film.

2. A method according to claim 1, c h a r a c t e r i z e d in that in one lateral area (13) and parallel to the cut (27) a line of weakening (29) is formed, pre-ferably a perforation (29), that in the overlapping position this lateral area (13) is placed in such a manner that it will turn outward in the finished bag (1), and that the overlapping lateral area (13, 15) are sealed by a longitudinally exten-ding welding (31) in a position between the perforation (29) and the outmost edge (33) of said lateral area in which said perforation has been maid.

3. A method according to claim 2, c h a r t e r i z e d in that the cut (27) and the line of weakening (29) are performed at the same time and that the welding is performed in a subsequent step.

4. A method according to any of the preceding claims, c h a r a c t e r i z e din that the overlapping joint (11) is made by a procedure in which the adhesive is applied in a strip (25) at one side of the film whereupon the cut (27) is made next to the applied strip adhesive, and that the part (13) of the film without adhesive is then placed into an overlapping position and put into contact with the lateral area (15) containing the adhesive.

5. A bag (1) produced from a substantially endless film which, during a filling procedure, is formed into closed individual bags, wherein between two closed ends (5, 9) the bag has an overlapping joint (11) which extends parallel to a longitudinal welding (3) of the film's lateral edges (17, 19), which welding (3) has been made when forming the closed individual bag (1), and that surfaces facing each other in the overlapping joint (11) are provided with an adhesive (25) of a know type which is able to glue several time, c h a r a c -t e r i z e d in that the opening of the bag is delimited at least by one of theside edges (at 15) made when cutting the film and that the overlapping joint (11) is positioned near one lateral edge of the bag (1) extending between the two closed ends (5, 9).

6. A bag according to claim 5, c h a r a c t e r i z e d in that the outward lateral area (13) of the overlapping joint (11) is provided with a line of weaken-ing (29), preferably a perforation, which extends in the longitudinal direction of the overlapping joint (11), and that a welding is provided in a position betweenthe line of weakening and the outmost edge of said outward lateral area in which the line of weakening has been made.

7. A bag according to claim 5 or 6, c h a r a c t e r i z e d in that the over-lapping joint (11) extends along one lateral edge of the bag on the face of the bag where the longitudinal welding (3) is positioned.

8. A film for use in the production of a bag according to any one of claims 5 to 7, wherein in a position between the film's lateral edges at least one overlap-ping joint (11) is provided wherein - between two overlapping surfaces facing each other - an adhesive has been provided which is of a known type and able to glue several time, c h a r a c t e r i z e d in that the overlapping joint (11) is arranged near one of the lateral edges (17) of the film.

9. A film according to claim 8, c h a r a c t e r i z e d in that the overlapping joint (11) extends in the longitudinal direction of the film and parallel to thelateral edges of the film.