Abstract:
An unsealing method for unsealing a packaging structure for a liquid container in which the packaging structure includes a covering member having an air vent sealing portion, a liquid supply sealing portion, and a connecting region which covers a connecting side of the liquid container and which connects the air vent and liquid supply scaling portions. The liquid supply sealing portion effects non-adhering sealing, and the connecting portion provides resistance against unsealing of the liquid supply portion. The covering member also has first and second regions which respectively include first and second resistance generation portions for generating resistance against unsealing. According to the unsealing method, the air vent is unsealed, the first resistance generating portion is separated from the liquid container, the liquid supply portion is unsealed, and the second resistance generating portion is separated. By virtue of this arrangement, the liquid container can be unsealed methodically without unexpected unsealings.

Description:
This application is a division of application Ser. No. 10/388,393, filed Mar. 17, 2003, the contents of which is incorporated herein by reference. 

   FIELD OF THE INVENTION AND RELATED ART 
   The present invention relates to an improved jacket for sealing a liquid container, which is for sealing a liquid container for storing recording liquid, for example, ink, supplied to the ink jet head of an ink jet recording apparatus, and which is removably connectable to the liquid supply path to the ink jet head. It also relates to a method for unsealing a liquid container fitted with such a liquid container sealing jacket. More specifically, it relates to a liquid container sealing jacket structured so that it is unlikely to allow such a problem as ink splash to occur, and a method for removing such a liquid container sealing jacket. 
   Conventionally, an ink jet recording head which ejects ink onto recording medium to form an image on the recording medium employs an ink container from which ink is supplied to the recording head through an ink supply tube or the like. There have been proposed various types of replaceable ink containers, which are independent from an ink jet recording head. Many of these replaceable ink containers comprise a shell, and a piece of ink absorbing member contained in the shell in order to retain ink. They are connected to the ink supply tube leading to an ink jet recording head. In order to facilitate the ink supply to the ink jet recording head, and also to prevent the ink leakage from the air vent of the ink container, through which the internal space of the ink container is connected to the ambient air, some of the containers have been known to be structured so that the ink content of the ink absorbing member is greater in the adjacencies of the ink outlet of the ink container than in the rest of the ink container, and smallest in the adjacencies of the air vent than in the rest of the ink container. 
   There is a possibility that ink will leak from an ink container of the above described replaceable type, through its ink outlet and/or air vent. Thus, it is a common practice to place a sealing jacket capable of sealing the ink outlet and air vent, around the ink container, in order to prevent the ink leakage. According to the prior art, a sealing jacket is placed around an ink container so that the ink outlet and air vent of the ink container are covered with the sealing jacket. Then, in order to keep the ink container hermetically sealed, the sealing jacket is glued, or thermally welded, to the ink container along the portions around the ink outlet and the portion around the air vent. A sealing jacket is inexpensive, and yet, is capable of reliably keeping an ink container hermetically sealed. Therefore, it is widely used to seal an ink container. All that is required of a user to unseal an ink container fitted with a sealing jacket, more specifically, to unseal the ink outlet and air vent sealed with the sealing jacket, is to peel the sealing jacket away from the adjacencies of the ink outlet and air vent, by directly pulling the sealing jacket. 
   There is a possibility that during the shipment of an ink container, a sealing jacket becomes partially undone due to the increase in the internal pressure of the ink container caused by the changes in the ambient factors. Thus, in order to prevent such an accident, a conventional sealing jacket has been very firmly glued, or thermally welded, to the ink container along the portions around the ink outlet and air vent; in other words, the adhesive strength between the sealing jacket and ink container is made substantial, around the ink outlet and air vent. Therefore, a user has to apply a substantial amount of muscular force, in order to remove the sealing jacket. 
   This creates the following problem. That is, in order to peel the sealing jacket from around the ink outlet and air vent, a user has to pull the sealing jacket with a substantial amount of muscular force, as described above. However, the substantial resistance coming from the adhesive strength between the sealing jacket and ink container suddenly disappears the moment the sealing jacket becomes completely separated from the portions of the ink container around the ink outlet or air vent. As a result, the user&#39;s hand is suddenly let go in the direction in which it was pulling the sealing jacket, yanking the sealing jacket away from the ink container. Therefore, there is the possibility that the ink remaining sealed by the sealing jacket will be splashed, in particular, from the ink outlet, soiling the user&#39;s hand as well as the surroundings. 
   There are two bodies of ink which are splashed: the first body of ink which is thought to be between the ink absorbent member and sealing jacket, and the second body of ink adhering to the sealing jacket itself. 
   Referring to  FIGS. 9(   a ),  9 ( b ), and  9 ( c ), the first body of ink is subjected to the pressure which acts in the direction in which the internal volume of the ink container  51  increases, that is, in the direction in which the ink within the ink container is drawn out. The first body of ink is also affected by the inertia generated by the movement of the sealing jacket  52  being abruptly peeled. As a result, the body of ink  54  between the ink absorbent member  53  and the sealing jacket  52  is abruptly stretched by the sealing jacket  52 . As a result, the body of ink  54  will abruptly split. However, as it abruptly splits, specks of ink which fail to remain on either the ink absorbent member  53  or sealing jacket  52 , splash. 
   Referring to  FIGS. 10(   a ),  10 ( b ), and  10 ( c ), the moment the sealing jacket  52  becomes completely separated from the ink outlet  55 , the sealing jacket  52  is briefly yanked by the above described sudden movement of the user&#39;s hand. As a result, the second body of ink  54   a , or the body of ink adhering to the surface of the sealing jacket, is sometimes shot out by the impact from the sudden movement of the sealing jacket  52 , being splashed. 
   In the case of some ink containers, the cap  62  is welded to the ink outlet  61  at the welding seam  64  in order to assure that the ink outlet  61  remains sealed, for the purpose of preventing these bodies of ink from being splashed. This type of ink container  63  is to be unsealed in the following manner. First, in order to break the welding seam  64  between the cap  62  and ink outlet  61 , the cap  62  is to be rotated in the direction opposite to the direction in which the cap  62  is to be rotated in the final stage of its removal. Then, the cap  62  is to be removed. Therefore, the internal pressure of the ink container  63  is not released while the cap  62  becomes literally separated from the ink outlet. Further, the cap  62  is removed after the breaking of the welding seam  64 , eliminating the problem that the cap  62  is abruptly moved away from the ink outlet. In other words, the type of ink splashing, which sometimes occurs to an ink container employing the sealing jacket shown in  FIG. 10 , does not occur to these types of ink container, since the cap  62  of this type of ink container is opened by rotating the cap  62 . 
   In the case of the ink containers with a cap structured as described above, the cap must be “twisted” to open it. “Twisting” means “turning the wrist while holding the cap”, which is an operation rather difficult for children, older people, or people having troubles with their hands or wrists, to perform. Moreover, the cap of this type of ink container is firmly welded to assure that the ink container remains sealed with the cap, adding to the level of the difficulty in the twisting the cap. Thus, a sealing jacket for an ink container, which is structured so that an ink container can be easily unsealed by anybody, has been desired. 
   SUMMARY OF THE INVENTION 
   The present invention is made in consideration of the above described problems, and its primary object is to provide a highly reliable sealing jacket for a liquid container, which is capable of preventing ink from splashing from the ink outlet of an ink container during the unsealing of the ink container, and yet can be easily removed by anybody, and also to provide a method for unsealing a liquid container fitted with such a sealing jacket. 
   According to an aspect of the present invention, there is provided a packaging structure for a liquid container including a liquid containing portion accommodating liquid, a liquid supply portion for supplying the liquid to an outside and an air vent for fluid communication with an ambience, comprising a covering member for covering and sealing said liquid supply portion and said air vent; said covering member including an air vent sealing portion for sealing said air vent and a liquid supply portion sealing portion for sealing said liquid supply portion, and a connecting region for covering a connecting side of said liquid container which connects said air vent sealing portion and said liquid supply portion sealing portion, wherein said liquid supply portion sealing portion effects non-adhering sealing for said liquid supply portion, and said connecting region provides a resistance against unsealing of said liquid supply portion. 
   According to another aspect of the present invention, there is provided an unsealing method for unsealing a packaging structure for a liquid container including a liquid containing portion accommodating liquid, a liquid supply portion for supplying the liquid to an outside and an air vent for fluid communication with an ambience, said packaging structure including a covering member for covering and sealing said liquid supply portion and said air vent; said covering member including; an air vent sealing portion for sealing said air vent and a liquid supply portion sealing portion for sealing said liquid supply portion, and a connecting region for covering a connecting side of said liquid container which connects said air vent sealing portion and said liquid supply portion sealing portion, wherein said liquid supply portion sealing portion effects non-adhering sealing for said liquid supply portion, and said connecting region provides a resistance against unsealing of said liquid supply portion, said method comprising a step of unsealing said air vent at said air vent sealing portion; a step of separating said first resistance generating portion from the side of said liquid container where said first resistance generating portion is provided; a step of unsealing said liquid supply portion at said liquid supply portion sealing portion where said liquid supply portion is sealed by the non-adhering sealing; and a step of separating said second resistance generating portion from the side of said liquid container where said second resistance generating portion is provided. 
   According to a further aspect of the present invention, there is provided a packaging structure for a liquid container having a liquid containing portion for containing liquid and a liquid supply opening for supplying the liquid, wherein said liquid supply opening is covered by a covering member, wherein said covering member has at least two independent adhered regions where said covering member is adhered to said liquid container at positions such that liquid supply opening is interposed between said two adhered regions. 
   According to a further aspect of the present invention, there is provided a packaging structure for a liquid container having a liquid containing portion for containing liquid and a liquid supply opening for supplying the liquid, wherein said liquid supply opening is covered by a covering member, wherein said covering member has independent adhered regions where said covering member is adhered to said liquid container and tearing means for tearing said covering member at respective positions such that liquid supply opening is interposed between said regions. 
   According to a further aspect of the present invention, there is provided a packaging structure for liquid container including a liquid containing portion accommodating liquid, a liquid supply portion for supplying the liquid to an outside and an air vent for fluid communication with an ambience, the packing structure includes a covering member for covering and sealing the liquid supply portion and the air vent; the covering member including; an air vent sealing portion for sealing the air vent and a liquid supply portion sealing portion for sealing the liquid supply portion, and a connecting region for covering a connecting side of the liquid container which connects the air vent sealing portion and the liquid supply portion sealing portion, wherein the liquid supply portion sealing portion effects non-adhering sealing for the liquid supply portion, and the connecting region provides a resistance against unsealing of the liquid supply portion. 
   A liquid container fitted with the above described sealing jacket can be unsealed following the steps described next. First, a user is to peel the sealing jacket by grasping one end of the sealing jacket on the liquid container. The sealing jacket is adhered to the liquid container by its two adherent portions positioned one for one on both sides of the liquid outlet in terms of the direction in which the sealing jacket is to be removed. Thus, first, one (first) of the adherent portions of the sealing jacket is peeled. While this portion is peeled, the length of the first adherent portion, in terms of the direction in which it is peeled, makes it possible for a user to realize the amount of muscular force necessary to be exerted to peel the sealing jacket, preventing therefore the sealing jacket from being peeled too fast by the application of an excessive amount of force. 
   At the end of the peeling of the first adherent portion, the amount of the force necessary to peel the sealing jacket suddenly reduces to virtually zero. However, the user has not been applying an excessive amount of muscular force, as described above. Therefore, it does not occur that the user&#39;s hand grasping the sealing jacket jerkingly moves due to the sudden reduction in the resistance. 
   The portion of the sealing jacket corresponding to the liquid outlet of the liquid container is not adherent. Thus, at the end of the peeling of the first adherent portion, the liquid outlet becomes unsealed. As described above, during this process of peeling the first adherent portion, the sealing jacket is not abruptly peeled. Therefore, the liquid in, or adhering to, the liquid outlet is not splashed the moment the liquid outlet becomes unsealed. In addition, the sudden reduction, to virtually zero, of the resistance, against which the force necessary to peel the sealing jacket is being applied the user, gives the user the “sense of completion” that the liquid outlet has just been unsealed. 
   Moreover, this sealing jacket structured as described above can also prevent the liquid on the sealing jacket itself from splashing because, the second adherent portion of the sealing jacket functions as the stopper for preventing the rest of the sealing jacket from being abruptly peeled away in “one quick stroke”. 
   Further, it is desired that this sealing jacket structured as described above has a sealing means positioned to hermetically seal the liquid storage portion as the sealing jacked is placed around an ink container, and also that in terms of the specific direction in which the sealing jacket is to be peeled, the first and second adherent portions of the sealing jacket are in front, and after, this sealing means, respectively. 
   Further, in the case of a liquid container having an air vent which connects the liquid storage portion to the ambient air, the air vent is desired to be in front of the sealing member, in terms of the specific direction in which the sealing jacket is to be peeled. With the provision of this structural arrangement, the air vent will open before the liquid outlet becomes unsealed during the peeling of the sealing jacket. Therefore, even if the internal pressure of the liquid container happen to have become higher, due to changes in the ambient temperature, than the ambient pressure, liquid can be prevented from being splashed from the liquid outlet the moment the liquid outlet becomes unsealed. 
   Further, the liquid container to be fitted with the sealing jacket structured as described above may be in the form of a rectangular parallelepiped. When giving the liquid container a rectangular parallelepiped shape, the shape is desired to be flat, and the liquid outlet is placed on the surface other than the largest surfaces. Such a liquid container is advantageous in terms of spatial efficiency, because when it is disposed in parallel by two or more, it occupies a smaller amount of space compared to a liquid container which is not in the above described form. 
   A liquid container shaped as described above is desired to be covered with the above described sealing jacket, at least across the surface having the ink outlet and the pair of surfaces contiguous to the surface having the ink outlet. Further, the first and second adherent portions of the sealing jacket for covering this liquid container correspond in position to the pair of liquid container surfaces contiguous to the surface with the liquid outlet, one for one. 
   Further, the sealing jacket is desired to be fitted around the ink container so that the second adherent portion of the sealing jacket, that is, the adherent portion positioned after the liquid outlet in terms of the specific direction in which the sealing jacket is to be peeled, covers the edge at which the liquid container surface with the liquid outlet intersects with the liquid container surface contiguous thereto. With the provision of this structural arrangement, it is possible to make the second adherent portion function as the above described stopper immediately after the unsealing of the ink outlet. Further, for the purpose of making the second adherent portion function as the stopper as soon as possible after the unsealing of the liquid outlet, the liquid outlet is desired to be disposed close to the liquid container surface corresponding in position to the second adherent portion of the sealing jacket. 
   Further, the liquid container is desired to have a sealing member for sealing the air vent connecting the internal space of the liquid container to the ambient air. This sealing member may be an integral part of the sealing jacket. When it is formed as an integral part of the sealing jacket, the sealing jacket is desired to be provided with a pair of perforations cut in parallel on the two sides of the sealing member, one for one, in terms of the direction in the sealing jacket is peeled. 
   As for the material for the sealing jacket, a sheet of film, preferably, a sheet of thermally shrinkable film, can used. The sealing jacket may be completely wrapped around a liquid container; it may be in the form of an endless belt. Further, it may be form of elastic material. 
   As for the means for attaching the sealing jacket to a liquid container, gluing or thermal welding may be employed. 
   As the above described sealing means, a cap may be employed. When a cap is used as the sealing means, the sealing portion of the cap is formed of elastic substance or elastomer. 
   The adherent portion of a sealing jacket, which is adhered to a liquid container, and the means for cutting the sealing jacket, may be independently disposed on the opposite sides with respect to the ink outlet. Such a design can also accomplish the above described objects of the present invention. 
   These and other objects, features, and advantages of the present invention will become more apparent upon consideration of the following description of the preferred embodiments of the present invention, taken in conjunction with the accompanying drawings. 

   
     BRIEF DESCRIPTION OF DRAWINGS 
       FIG. 1  is a drawing for describing the overall structure of the first embodiment of an ink container in accordance with the present invention,  FIGS. 1(   a ) and  1 ( b ) being a perspective and front plan views thereof, respectively. 
       FIG. 2  is a sectional view of the ink container in  FIG. 1 , at a plane parallel to the largest wall of the ink container. 
       FIG. 3  is a perspective view of the sealing jacket for sealing the ink container in  FIG. 1 . 
       FIG. 4  is a sectional view of the ink outlet of the ink container, and the cap therefor, for showing the relationship between the ink outlet and the cap on the ink outlet. 
       FIG. 5  is a perspective drawing of the ink container in  FIG. 1 , for showing the method for peeling the sealing jacket from the ink container in  FIG. 1 ,  FIG. 1(   a ) corresponding to the ink container prior to the unsealing of the ink outlet of the ink container;  FIG. 1(   b ) corresponding to the ink container after the removal of the sealing jacket;  FIG. 1(   c ) corresponding to the ink container immediately after the beginning of the peeling of the first adhesive portion shown in  FIG. 1 ; and  FIG. 1(   d ) corresponding to the ink container during the advanced stage of the peeling of the adherent portion of the sealing jacket. 
       FIG. 6  is a frontal plan view of the ink container in  FIG. 1 , during the unsealing of the ink outlet thereof. 
       FIG. 7  is a perspective view of the second embodiment of an ink container in accordance with the present invention,  FIG. 7(   a ) showing the ink container after the unsealing thereof, and  FIG. 7(   b ) showing the ink container, the ink outlet of which is sealed with the sealing jacket. 
       FIG. 8  is a perspective view of the third embodiment of an ink container in accordance with the present invention, the ink outlet of which is sealed with the sealing jacket. 
       FIG. 9  is a sectional drawing of the ink outlet of an ink container in accordance with the prior art, for describing the causes of the ink splash which occurs when the ink container is unsealed. 
       FIG. 10  is a sectional drawing of the ink outlet of an ink container in accordance with the prior art, for describing the causes of the ink splash which occurs when the ink container is unsealed. 
       FIG. 11  is a plan view of the cap, and its adjacencies, of an example of an ink container in accordance with the prior art, for showing a structural arrangement in which the cap is utilized as the means for unsealing the ink container. 
       FIG. 12  is a perspective view of the ink container in  FIG. 1 , for showing the adherent portion of the sealing jacket. 
       FIG. 13  is a frontal plan view of the ink container in  FIG. 1 ,  FIG. 13(   a ) showing the ink container after the first adherent portion of the sealing jacket has been peeled, as far as it could be, in the direction parallel to and  FIG. 13(   b ) showing the ink container after the sealing jacket has been peeled in the direction which is not parallel to the liquid container surface corresponding in position to the first adherent portion. 
       FIG. 14  is a drawing of the fourth embodiment of an ink container in accordance with the present invention,  FIGS. 14(   a ) and  14 ( b ) being perspective and frontal plan views, respectively. 
       FIG. 15  is a drawing of the fifth embodiment of the present invention in accordance with the present invention,  FIGS. 15(   a ),  15 ( b ),  15 ( c ), and  15 ( d ) being perspective view, side view, front view, and enlarged view of the cut interval change point, and its adjacencies, of one of the two perforations, at which the cut interval of the perforation is changed, respectively. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Embodiment 1 
     FIG. 1  is a drawing for describing the overall structure of the first embodiment of an ink container in accordance with the present invention,  FIGS. 1(   a ) and  1 ( b ) being perspective and front views the container, respectively. 
   The ink container  100  in  FIG. 1  comprises: an ink container proper  101  for holding ink; an ink outlet  102  through which ink is supplied outward (for example, toward ink jet recording head); an air vent  104  through which air is introduced or expelled; a sealing member  105  for sealing the air vent  104 ; and a sealing jacket  103  for covering the entirety of the ink container proper  101  as well as the ink outlet  102 . The sealing jacket  103  comprises a cap  121  for sealing the ink outlet  102 ; and a wrapping member  120  which wraps the ink container proper  101  as well as the cap  121 . The sealing member  105  may be an integral part of the wrapping member  120 . Further, the wrapping member  120  has first and second portions  110  and  111 , respectively, coated with adhesive, which hereinafter will be referred to as first and second adherent portions ( FIG. 1(   b )). 
   Incidentally, in  FIG. 11 , in order to show the structure of the ink container  100 , the wrapping member  120  is pictured as a transparent member, and the adherent portions  110  and  111  are hatched. 
     FIG. 2  is a sectional view of the ink container proper  101  at a plane parallel to the largest wall thereof. As is evident from this drawing, the ink container proper  101  is in the form of a parallelepiped, and is relatively flat. The internal space (liquid storage portion) comprises two chambers: a chamber  130  in which a negative pressure generating member is held, and ink storage chamber  131  located next to the negative pressure generating member holding chamber  130 . The negative pressure generating member absorbs and retains ink by generating negative pressure, and the ink storage chamber  131  holds ink. 
   The partition wall partitioning the negative pressure generating member holding chamber  130  from the ink storage chamber  131  has a passage through which the two chambers are in connection with each other, and which is located at the edge of the negative pressure generating member holding chamber  130  next to the bottom wall of the ink container proper  101 . The negative pressure generating member holding chamber  130  has the ink outlet  120  and air vent  104 . The ink outlet  120  is attached to the bottom wall thereof. The air vent  104  is the passage between the internal space of the ink container proper  101  and the ambience, and is in the ceiling portion of the negative pressure generating member holding chamber  130 . The ink outlet  102  is filled with a compressed member  133 , as an ink drawing member, for efficiently drawing ink into the ink supply tube leading to the ink jet recording head. 
   Next, referring to  FIG. 2(   b ), the ink delivery system of the ink container  100  will be described. 
   As the ink container  100  is mounted into an ink jet recording apparatus (unshown), the ink drawing tube  200  of the main assembly of the image forming apparatus enters the ink outlet  102 , pressing on the compressed member  133 . Some of the ink drawing tubes  200  have a filter  201 , which is attached to the opening of the ink drawing tube  200  as shown in the drawing. Then, as the ink jet recording apparatus is operated, ink is ejected from the ink jet recording head (unshown), generating such force that suctions the ink from the ink container proper  101 . As a result, the ink in the ink storage chamber  131  is drawn into the negative pressure generating member holding chamber  130 , and then, is further drawn into the ink supply tube  200  through the negative pressure generating member  132 , being thereby supplied to the ink jet recording head. Consequently, the internal pressure of the ink storage chamber  131  drops, creating pressure difference between the ink storage chamber  131  and negative pressure generating member holding chamber  130 . This pressure difference temporarily increases as the ink is continuously supplied to the ink jet recording head due to its recording operation. However, since the negative pressure generating member holding chamber  130  has the air vent  104 , through which the negative pressure generating member holding chamber  130  is open to the ambience, the ambient air enters the ink storage chamber  131  through the negative pressure generating member holding chamber  130 , neutralizing the pressure difference between the ink storage chamber  131  and negative pressure generating member holding chamber  130 . During the image forming operation, this creation and neutralizing of the pressure difference is repeated, making it possible for the ink to be smoothly supplied to the ink jet recording head. 
   Next, the sealing member  105  for sealing the air vent  104  will be described. 
   The air vent  104  is in the wall of the ink container proper  101 , which opposes the wall of the ink container proper  101  having the ink outlet  102 . It is open immediately adjacent to the negative pressure generating member  132 . The sealing member  105  for sealing the air vent  104  is in the form of a piece of film, and is on the wall of the ink container proper  101 , which has the air vent  104 , being glued thereto in a manner to seal the air vent  104 . The sealing member  105  should be off the ink container proper  101  when mounting the ink container  100  into the ink jet recording apparatus (unshown). Therefore, the sealing member  105  is attached to the ink container proper  101  using such an adhesive, or welding method, that allows it to be peeled away from the ink container proper  101  when necessary. 
     FIG. 3  is a perspective view of the sealing jacket  103  for sealing the ink container proper  101  as shown in  FIG. 1 . The hatched portions in the drawing represent the portions of the sealing jacket  103  by which the sealing jacket  103  is attached to the ink container proper  101 . The sealing jacket  103  is in the form of an endless belt or band as shown in  FIG. 3 . As described before, the sealing jacket  103  comprises the cap  121  and wrapping belt portion  120 . Referring to  FIG. 1 , the cap  121  is positioned so that it fits around the ink outlet  102  of the ink container proper  101  as the ink container proper  101  is wrapped with the sealing jacket  103 . The material for the cap  121  is different from the material for the wrapping belt portion  120 . The cap  121  is a member to be pressed on the ink outlet  102  to seal the ink container proper  101 . Therefore, an easily pliable elastomer is desirable as the material for the cap  121 . 
   The cap  121  of this embodiment is formed of two materials. That is, the portion of the cap  121  which is placed in contact with the ink outlet  102  to seal the ink container proper  101  is formed of elastomer, whereas the portion of the cap  121  surrounding the portion formed of elastomer is formed of polypropylene ( FIG. 4 ). 
   Referring to  FIG. 3 , the cap  121  is fixed to the wrapping belt portion  120 . As for the method to attach the cap  121  to the wrapping belt portion  120 , the polypropylene portion of the cap  121  surrounding the elastomer portion of the cap  121  is glued, or welded, to the wrapping belt portion  120 . Although the wrapping belt portion  120  and cap  121  of this embodiment are held together by welding, or with the use of adhesive, there is absolutely no problem even if a means other than welding or adhesive may be employed to hold the wrapping belt portion  120  and cap  121  together, as long as it assures that the cap  121  remains securely held by the wrapping belt portion  120 . 
   Not only must the wrapping belt portion  120  be able to compactly wrap the entirety of the ink container proper  101  while being able to keep the cap  121  pressed against the ink outlet  102 , as shown in  FIG. 1 , but also it must be able to keep the cap  121  against the ink outlet  102 . In consideration of this fact, the material for the wrapping belt portion  120  is desired to be such film that can be thermally shrunk to conform to the external contour of the ink container proper  101 . Obviously, the wrapping belt portion  120  may be a belt of film, one end of which can be welded to the other in a manner to form an endless belt after being wrapped around the ink container proper  101  so that the cap  121  is covered and retained by the wrapping belt portion  120 . 
   Referring to  FIGS. 1 and 3 , the sealing member  105  is an integral part of the wrapping belt portion  120 , which faces the wall of the ink container proper  101  having the air vent  104 . The sealing member  105  is differentiated from the rest of the wrapping belt portion  120  by two straight lines of perforation  115  parallel to each other. With the provision of this structural arrangement, the wrapping belt portion  120  can be easily torn off by simply lifting the sealing member  105 , exposing the air vent  104  as well as the ink outlet. In other words, the air vent  104  and ink outlet  102  can be exposed by a single action. 
   The wrapping belt portion  120  is fixed to the ink container proper  101  by the two adherent portions, that is, first and second adherent portions, of the wrapping belt portion  120  corresponding, one for one, to the two lateral surfaces of the ink container proper  101  which sandwich the surface of the ink container  101  having the ink outlet  102  (surfaces contiguous to the surface having ink outlet). Since these first and second adherent portions must be peelable from the ink container proper  101  when removing the wrapping belt portion  120 , they are glued, or welded, to the ink container proper  101 . 
   Next, the method for covering the ink container proper  101 , inclusive of the ink outlet, with the sealing jacket  103  will be described. 
   The wrapping belt portion  120  of the sealing jacket  103  is in the form of a cylinder, which is greater in circumference than the portion of the ink container proper  101  to be wrapped by the wrapping belt portion  120 . In order to the wrap the ink container proper  101  with the sealing jacket  103 , the ink container proper  101  is placed inward of the wrapping belt portion  120 . Then, the ink container proper  101  and sealing jacket  103  are positioned relative each other so that the cap  121  is placed in contact with the ink outlet  102 . Then, the cap  121  is kept pressed on the ink outlet  102  with the use of a retaining jig (unshown), the structure of which is optional as long as it does not damage the elastomer portion  121   a  of the cap  121 . 
   Next, the first and second adherent portions  110  and  111  coated with adhesive are pressed on the corresponding lateral surfaces of the ink container proper  101  to adhere thereto the first and second adherent portions  110  and  111 . During this process, attention must be paid so that no air is left between the adherent portions  110  and  111  and corresponding surfaces of the ink container proper  101 . Next, the wrapping belt portion  120  formed of shrinkable film, is thermally shrunk, while keeping the cap  121  pressed on the ink outlet  102  with the above described retaining jig, until the sealing jacket  103  conforms to the external contour of the ink container proper  101  tightly enough for the resultant tensile force of the sealing jacket  103  to keep the ink outlet sealed by the cap  121 . Thereafter, the ink container proper  101  is released from the retaining jig, ending the process for covering the ink container proper  101  with the sealing jacket  103 .  FIG. 1  shows the ink container  100  after the completion of this process. 
   Next, referring to  FIG. 4 , the relationship between the ink outlet  102  and cap  121  after the thermal shrinking of the sealing jacket  103  will be described.  FIG. 4  is a sectional view of the ink outlet  102 , and the cap  121  on the ink outlet  102 , for showing how the ink outlet  102  is kept sealed by the cap  121 . In this drawing, the ink container proper  101  has a cylindrical portion  150 , which projects from the edge of the ink outlet  102  in a manner to surround the ink outlet. The internal diameter of the cylindrical portion  150  is roughly the same as the diameter of the ink outlet  102 . The end surface of the cylindrical portion  150  has a projection  151 , and the elastomer portion  121   a  of the cap  121 , with which the collar rib  150  makes contact, has a groove  125  with a V-shaped cross section (which hereinafter may simply be referred to as V-shaped groove), into which the projection  151  of the cylindrical portion  150  fits. 
   Referring to  FIG. 4 , as the projection  151  is pressed into the V-shaped groove  125 , the projection enters the V-shaped groove  125 , pressing on the elastomer portion  121  as if widening the groove  125 . Thus, as the projection  151  enters the V-shaped groove  125 , the slanted surface of the V-shaped groove  125  conforms to the contour of the projection  151 , airtightly sealing between the projection  151  and the slanted surface of the V-shaped groove  125 . As a result, the ink outlet  102  is airtightly sealed. 
   Next, referring to  FIGS. 5(   a )– 5 ( d ), and  FIG. 6 , one of the primary objects of the present invention, that is, a method for unsealing an ink container in accordance with the present invention, will be described.  FIG. 5(   a ) is a perspective view of an ink container  100  in accordance with the present invention prior to the unsealing of the ink outlet  102 ;  FIG. 5(   b ), a perspective view of the same during the removal of the sealing member  105 ;  FIG. 5(   c ), a perspective view of the ink container shortly after the beginning of the peeling of the first adherent portion  110  of the wrapping belt portion  120 ; and  FIG. 5(   d ) is a perspective view of the same during the advanced stage of the peeling of the first adherent portion  110  of the wrapping belt portion  120 .  FIG. 6  is a frontal plan view of the ink container  100  in accordance with the present invention during the unsealing of the ink outlet  102 . 
   This embodiment of an ink container in accordance with the present invention is to be unsealed in the following order. First, the sealing member  105  covering the air vent  104  is to be removed to expose the air vent  104 . This process should be carried out first for the following reason. The internal pressure of the ink container proper  101  sometimes becomes higher than the ambient pressure due to the changes in the ambient factors, for example, temperature. Thus, it is possible that ink will splash out of the unsealed openings of the ink container proper  101  as the ink container proper  101  is unsealed. This possibility is greater when the ink outlet side of the ink container proper  101 , where the ink content in the negative pressure generating member  132  in the ink container proper  101  is greater than in the rest of the negative pressure generating member  132 , is unsealed first than when the air vent side of the ink container proper  101 , where the ink content in the negative pressure generating member  132  ( FIG. 2 ) in the ink container proper  101  is less than in the rest of the negative pressure generating member  132  is unsealed first. This is why the sealing member  105  covering the air vent  104  should be removed first. 
   First, a user is to remove the sealing member  105  by grasping the tab  112  ( FIG. 5(   a )) of the sealing jacket  103  extending beyond the corresponding lateral surface of the ink container proper  101 . Since the pair of straight perforations  115  for making it easier for the sealing member  105  to be removed border between the sealing member  105  and the rest of the sealing jacket  103 , it is easy for the user to tear the sealing jacket  103  to remove the sealing member  105 . The user can confirm, by finding these perforations, whether the direction in which the user is about to peel the sealing member  105  is right or wrong. As the sealing member  105  is pulled by the user in the direction indicated by an arrow mark A in the drawing, not only does the sealing member  105  become separated from the ink container proper  101 , but also, the portion of the sealing jacket  103  between the two perforations  115  is removed. As the sealing member  105  is removed, the air vent  104  is exposed. Further, the removal of the portion of the sealing jacket  103  between the two perforations  115  gives the sealing jacket  103  a U-shaped cross section as seen from the direction parallel to its surface. 
   Incidentally, it is desired that the tab  112  of the sealing member  105  is provided with a clear marking for allowing a user to recognize the presence of the tab  112 . 
   Next, the peeling of the sealing jacket  103  will be described. After the removal of the sealing member  105 , the sealing jacket  103  remains attached to the ink container proper  101 , being in conformation to the external contour of the ink container proper  101 , and therefore, maintaining the aforementioned U-shaped cross section ( FIG. 5(   b )). The user is to peel the sealing jacket  103  by grasping one of the ends of the sealing jacket  103  remaining adhered to the two surfaces of the ink container proper  101  which oppose each other with the presence of the surface of the ink container proper  101  with the ink outlet  102  between them. In terms of the widthwise direction of the sealing jacket  103 , the first adherent portion  110  of the sealing jacket  103  ( FIG. 1(   b )), and the second adherent portion  110  of the sealing jacket  103  on the opposite side with respect to the ink container proper  101  ( FIG. 1(   b )), are adhered to the ink container proper  101  from one edges to the others. However, in terms of the lengthwise direction of the sealing jacket  103 , the portions of the sealing jacket  103  next to the aforementioned perforations  115 , were not made adherent. These portions of the sealing jacket  103  constitute the tab  116  for grasping the sealing jacket in order to peel the sealing jacket  103 . This embodiment of an ink container, that is, the ink container  100 , is structured so that it is unnecessary to clearly indicate the direction in which the sealing jacket  103  is to be peeled; the sealing jacket  103  can be peeled from either end. For the sake of convenience in description, the clockwise direction is assumed to be the right direction in which the sealing jacket  103  is to be peeled. 
   The first adherent portion  110  ( FIG. 1(   b )), and the second adherent portion  111  on the opposite side with respect to the ink container proper  101  ( FIG. 1(   b )), are adhered from one edge to the other in terms of the widthwise direction of the sealing jacket  103 , making it difficult to peel the sealing jacket  103  without using the tab  112 , and therefore, compelling the user to remove the sealing jacket  103  primarily using the tab  112  defined by the present invention. 
   In order to peel the sealing jacket  103 , first, the adherent portion  110  is to be pulled in the direction indicated by an arrow mark B as shown in  FIG. 5(   c ). A user should know that the sealing jacket  103  should be gradually peeled, instead of abruptly, because the first adherent portion  110  is pasted to the surface of the ink container proper  101  by a substantial length in terms of the lengthwise direction of the sealing jacket  103 . As the user gradually peels the first adherent portion  110 , the user can realize the proper amount of force (stress) necessary to peel the sealing jacket  103 , refraining from applying an excessive amount of force to abruptly peel the sealing jacket  103 . 
   As the first adherent portion  110  is gradually peeled to its bottom edges, the peeling of the first adherent portion  110  ends. The moment the peeling of the first adherent portion  110  ends, the adhesive strength, between the first adherent portion  110  and corresponding surface of the ink container proper  101 , against which force is applied by the user to peel the sealing jacket  103  becomes zero. Therefore, without the anticipation of the end of the peeling of the sealing jacket  103 , the hand of the user may be let go suddenly in the direction indicated by the arrow mark B the moment the peeling of the first adherent portion  110  ends. This problem that the hand of the user grasping the sealing jacket  103  is let go abruptly in the arrow direction can be prevented by regulating the amount of the adhesive strength between the first adherent portion  110  and the corresponding wall of the ink container proper  101 . 
   Referring to  FIG. 6 , after the completion of the peeling of the first adherent portion  110 , the cap  121  which was kept by the sealing jacket  103 , in the position in which it seals the ink outlet  102 , is removed from the ink outlet  102  in a manner to rotate about the edge (rotational center C in  FIG. 6 ) of the second adherent portion  111  closest to the ink outlet  102 , unsealing the ink outlet  102 . As described above, during this process of removing the cap  121 , the movement of the hand of the user remains well controlled, that is, the user&#39;s hand does not move jerkingly. Therefore, the phenomenon that the ink between the ink outlet  102  and cap  121  splashes, instead of remaining adhered to the ink outlet  102  and/or cap  121 , as it is accelerated by the sudden movement of the sealing jacket  103  caused by the jerky movement of the user&#39;s hand, does not occur. Further, the sudden reduction of the force necessary to peel the sealing jacket  103  to zero makes it possible for the user to sense the completion of the unsealing of the ink outlet  102 . 
   Further, when this unsealing method is used, the second adherent portion  111  functions as the stopper for preventing the abrupt peeling of the sealing jacket  103 , that is, the cause of the splashing of the ink on the sealing surface of the cap  121 , preventing therefore the ink on the sealing surface of the cap  121  from being splashed. Referring to  FIG. 6 , for the purpose of making the stopper, or the second adherent portion  111 , function as soon as the ink outlet is unsealed, it is desired that the bottom edge of the adherent portion  111  coincides with the edge between the surface of the ink container proper  101  to which the second adherent portion  111  is adhered, and the surface of the ink container proper  101  having the ink outlet  102 . Further, for the purpose of making the second adherent portion  111  function as the stopper as quickly as possible after the unsealing of the ink outlet  102 , the ink outlet  102  should be disposed adjacent to the surface of the ink container proper  101  to which the adherent portion  111  is adhered. Further, in order to ensure that the second adherent portion  111  stops the peeling action, the adhesive strength between the second adherent portion  111  and the corresponding surface of the ink container proper  101  should be greater than that between the first adherent portion  110  and the corresponding surface of the ink container proper  101 . As long as the second adherent portion  111  reliably functions as the stopper quickly after the completion of the peeling of the first adherent portion  110 , the cap  121  will be held close to the ink outlet  102 , almost directly facing the opening of the ink outlet  102 . Therefore, should the ink be splashed from the cap  121 , the splashed ink flies into the cap  121 , being trapped therein, and therefore, being prevented from being splashed beyond the cap  121  and sealing jacket  103 . In order to make the second adherent portion  111  more effectively function as the stopper, this embodiment of an ink container, or the ink container  100 , has been designed so that the direction, in which the sealing jacket  103  will be pulled just before the ink outlet  102  begins to be unsealed, becomes virtually perpendicular to the surface of the ink container proper  101  having the ink outlet  102 . This is for the following reason. The moment the peeling of the first adherent portion  110  of the sealing jacket  103  is completed, the force applied to peel the first adherent portion  110  turns into such force that works in the direction to shear the second adherent portion  111 . Thus, the above described design is employed to make it rather difficult to remove the second adherent portion  111 . Next, referring to  FIGS. 13(   a ) and  13 ( b ), what will occur as the first adherent portion  110  is peeled in various manners by a user will be described.  FIG. 13(   a ) shows the ink container  100 , the sealing jacket  103  of which is extended as far as it can be extended, in the direction indicated by an arrow mark E, which is parallel to the surface of the ink container proper  101  to which the first adherent portion  110  had once been adhered.  FIG. 13(   b ) shows the ink container  100 , the sealing jacket  103  of which is being pulled in the direction indicated by an arrow mark F, which is not parallel to the surface of the ink container proper  101 , to which the first adherent portion  110  had once been adhered. Even if the sealing jacket  103  is peeled as shown in  FIG. 13(   a ) or  13 ( b ), the presence of the second adherent portion  111 , which functions as the stopper, regulates the distance (l) from the cap  121  to the ink outlet  102 . When a conventional sealing jacket (tape) as the sealing means was employed, the distance between the cap  121  and ink outlet  102  was not regulated after the unsealing of the ink outlet  102 . In comparison, when a sealing jacket  103  in accordance with the present invention is employed, the distance (l/t) the cap  121  is moved from the ink outlet  102  per unit of time (t) can be substantially smaller, making it possible to prevent the ink splash with the provision of the structural arrangement in this embodiment, should ink splash, the sealing jacket  103  itself functions as an ink catcher, minimizing the contamination traceable to the ink splash. 
   The second adherent portion  111  of the sealing jacket  103  is to be peeled after the unsealing of the ink outlet  102 . The second adherent portion  111  is also adhered to the ink container proper  101  across a substantial range, as is the first adherent portion  110 , in terms of the lengthwise direction of the sealing jacket  103 . Thus, the user is to gradually peel the sealing jacket  103 , while sensing the force necessary for peeling the second adherent portion  111  of the sealing jacket  103 . During this process of peeling the second adherent portion  111 , the sealing surface of the cap  121 , on which ink is present, can be seen. Therefore, the user is reminded that the adherent portion  111  of the sealing jacket  103  must also be cautiously peeled until the sealing jacket  103  is completely removed. 
   In this embodiment, the first and second adherent portions  110  and  111  are adhered to the ink container proper  101  across the entire range in term of the widthwise direction of the sealing jacket  103 . However, in order to reduce the amount of the force necessary at the initial stage of the peeling of the sealing jacket  103 , they may be adhered in a different pattern such as the one shown in  FIG. 12 ; the employment of such a pattern causes no problem at all. 
   The actions required of a user in order to unseal the ink outlet  102  of this embodiment of the present invention, that is, the ink container  100 , are only to peel the sealing member  105  and to peel the sealing jacket  103  as shown in  FIGS. 5(   a )– 5 ( d ). In both actions, all that is required to peel them is to grasp the tab, or the tab-like portion, and pull it; in other words, anyone can easily unseal the ink outlet  102 . 
   Embodiment 2 
   Next, referring to  FIG. 7 , the second embodiment of an ink container in accordance with the present invention will be described. 
     FIG. 7  shows the second embodiment of an ink container in accordance with the present invention.  FIG. 7(   a ) is a perspective view of the ink container in the unsealed state, and  FIG. 7(   b ) is a perspective view of the ink container, the ink outlet of which is sealed with the sealing jacket. 
   The ink container  100  structured as depicted in  FIG. 7  is a liquid container capable of holding three inks different in color in its ink container proper  101 , having three ink outlets  102 . The ink container  100  has three chambers partitioned by ribs. Each chamber is filled with a negative pressure generating member ( FIG. 2 ), holding an ink different in color from the inks in the other chambers. The ink container proper  101  is in the form of a rectangular parallelepiped, and is greater in the vertical dimension than in the horizontal dimension as shown in  FIG. 7 . 
   The sealing jacket  103  is formed of rubber, and is U-shaped. This embodiment of an ink container  100  is relatively flat, and the sealing jacket  103  covers the ink container  100  across the three surfaces: the surface with the ink outlet  102 , and the largest pair of surfaces sandwiching the surface having the ink outlet  102  (surfaces contiguous to surface with ink outlet). The direction in which the sealing jacket  103  is laid does not need to be limited to the direction in which the sealing jacket  103  of this embodiment is laid; for example, the sealing jacket  103  may be placed across the surface with the ink outlet, and the pair of surfaces contiguous to the surface with the ink outlet, other than the largest pair of surfaces. The sealing jacket  103  has first and second adherent portions  110  and  111 , which are positioned so that as the sealing jacket  103  is placed on the ink container  100 , they will be on the pair (largest pair) of the surfaces of the ink container proper  101  contiguous to the surface of the ink container proper  101  with the ink outlet  102 . The first and second adherent portions  110  and  111  are glued to the corresponding surfaces of the ink container proper  101 . The sealing jacket  103  is formed of elastic rubber. Therefore, the sealing jacket  103  can be glued to the ink container proper  101 , in the stretched state, so that the ink outlet  102  is airtightly sealed by the cap  121 . Even through this ink container  100  has three ink outlets, all three ink outlets  102  can be sealed with a single cap  121  without causing any problem. The method for unsealing the ink outlets  102  is the same as the method for unsealing the ink outlet of the first embodiment of the present invention; the sealing jacket  103  is to peeled in the direction indicated by an arrow mark D in  FIG. 7(   b ). 
   Like the first embodiment, this embodiment can prevent the phenomenon that the ink between the ink outlet  102  and cap  121  splashes, instead of remaining adhered to the ink outlet  102  and/or cap  121 , as it is accelerated by the sudden movement of the sealing jacket  103  caused by the jerky movement of the hand of the user. Further, the second adherent portion  111  functions as the stopper for temporarily halting the peeling action of the user, preventing therefore the ink on the sealing surface of the cap  121  from being splashed. 
   Embodiment 3 
   Next, referring to  FIG. 8 , the third embodiment of an ink container in accordance with the present invention will be described. 
     FIG. 8  is a perspective view of the third embodiment of the present invention, the ink outlet of which is sealed with the sealing jacket. 
   The ink container  100  shown in  FIG. 8  has two chambers: an ink storage chamber, and a negative pressure generating member storage chamber filled with a negative pressure generating member. The wall of the ink storage chamber has an ink outlet (unshown), the opening of which is filled with a filter (unshown). 
   The sealing jacket  103  is formed of film, and is U-shaped. This embodiment of an ink container  100  is relatively flat, and the sealing jacket  103  covers the ink container  100  across the three surfaces: the surface with the ink outlet  102 , and the largest pair of surfaces sandwiching the surface having the ink outlet  102  (surfaces contiguous to surface with ink outlet). Each of the largest pairs of surfaces has a step. The direction in which the sealing jacket  103  is placed on the ink container proper  101  does not need to be limited to the direction in which the sealing jacket  103  of this embodiment is placed; for example, the sealing jacket  103  may be placed across the surface with the ink outlet, and the pair of surfaces contiguous to the surface with the ink outlet, other than the largest pair of surfaces. The sealing jacket  103  has first and second adherent portions  110  and  111 , which are positioned so that as the sealing jacket  103  is placed on the ink container  100 , they will be on the pair (largest pair) of the surfaces of the ink container proper  101  contiguous to the surface of the ink container proper  101  with the ink outlet  102 . The first adherent portion  110 , and the second adherent portion  111  which opposes across the ink container proper  101 , ate spot-welded to the corresponding surfaces of the ink container proper  101 . The method for unsealing the ink outlets  102  is the same as the method for unsealing the ink outlet of the first and second embodiments of the present invention; the sealing jacket  103  is to be peeled in the direction indicated by an arrow mark E in  FIG. 8 . 
   The sealing jacket  103  is to be peeled in the following manner. Referring to  FIG. 8 , first, the adherent portion  110  is to be pulled in the direction indicated by the arrow mark E. A user should know that the sealing jacket  103  should be gradually peeled, instead of abruptly, because the first adherent portion  110  is spot-welded to the surface of the ink container proper  101  at plural spots  110   a  in a straight line in the lengthwise direction of the sealing jacket  103 . As the user gradually peels the first adherent portion  110 , the user can realize the proper amount of force (stress) necessary to peel the sealing jacket  103 , being enabled to refrain from applying an excessive amount of force which will result in the abrupt peeling the sealing jacket  103 . 
   As the first adherent portion  110  is gradually and continually peeled to its bottom edges, which coincide with the bottom edge of the ink container proper  101 , the peeling of the first adherent portion  110  ends. At the same time as the peeling of the first adherent portion  110  ends, the adhesive strength, between the first adherent portion and the corresponding surface of the ink container proper  101 , against which force is applied to the sealing jacket  103  to peel the sealing jacket  103  becomes zero. Therefore, without the anticipation of the loss of the resistance from the adhesive strength between the first adherent portion  110  and the corresponding wall of the ink container proper  101  at the end of the peeling of the first adherent portion  110  of the sealing jacket  103 , the hand of the user may be suddenly let go in the direction indicated by the arrow mark E due to the loss of resistance, at the same time as the peeling of the first adherent portion  110  ends. This problem that the hand of the user grasping the sealing jacket  103  is suddenly let go in the arrow direction can be avoided by setting the adhesive strength between the first adherent portion  110  and the corresponding wall of the ink container proper  101  to a level at which an excessive amount of force is not necessary to peel the first adherent portion  110 . 
   Referring to  FIG. 6 , after the completion of the peeling of the first adherent portion  110 , the cap  121  which was kept, by the sealing jacket  103 , in the position in which it seals the ink outlet  102 , is removed from the ink outlet  102  in a manner to rotate about the welding spot (unshown) of the second adherent portion  111  closest to the ink outlet  102 , unsealing the ink outlet  102 . As described above, during this process of removing the cap  121 , the movement of the hand of the user remains well controlled, and therefore, it does not occur that the ink outlet  102  is abruptly unsealed. Therefore, the phenomenon that the ink between the ink outlet  102  and cap  121  is accelerated by the abrupt movement of the sealing jacket  103  caused by the jerky movement of the user&#39;s hand, and splashes, instead of remaining adhered to the ink outlet  102  and/or cap  121 , does not occur. Further, the sudden loss of the resistance coming from the adhesive strength between the first adherent portion  110  and ink container proper  101  makes it possible for the user to sense the completion of the unsealing of the ink outlet  102 . 
   Like the first and second embodiments, this embodiment can also prevent the sealing jacket  103  from being jerked at the end of the peeling of the first adherent portion  110  during the unsealing of the ink outlet  102 , preventing therefore the phenomenon that the ink between the ink outlet  102  and cap  121  is accelerated by the jerking of the user&#39;s hand, and splashes, instead of remaining adhered to the ink outlet  102  and/or cap  121 . Further, this embodiment is also capable of preventing the ink on the sealing surface of the cap  121  from splashing. 
   Embodiment 4 
   Next, referring to  FIG. 14 , the fourth embodiment of the present invention will be described. This embodiment of an ink container in accordance with the present invention is similar to the first embodiment, except for the sealing jacket  103  and sealing member  105 . Thus, this embodiment will be described regarding only the sealing jacket  103  and sealing member  105 , and the method for unsealing the portions sealed by the sealing jacket  103  and sealing member  105 .  FIG. 14(   a ) is a perspective view of this embodiment, and  FIG. 14(   b ) is a side view of this embodiment.  FIG. 14(   c ) is a frontal plan view of this embodiment. 
   First, referring to  FIG. 14 , the sealing jacket  103  of the ink container  100  will be described. The sealing jacket  103  comprises a wrapping belt portion  120  and a sealing jacket  103  formed of the same materials as the materials for the wrapping belt portion  120  and sealing jacket  103  of the first embodiment. It is wrapped around the ink container proper  101 . It is long enough to be extendable a certain length from the ink container proper  101  roughly in parallel to the surface of the ink container proper  101 , that is, perpendicular to the pair of the largest surfaces of the ink container proper  101 , after being wrapped once around the ink container proper  101 . It is formed by cutting a part of the sealing jacket  103  in the form of a tab. Further, this sealing jacket  103  is provided with two straight perforations  510 , which extend one for one from the two ends (tear start points  510 ) of the base portions of the tab  500  in such a manner that as the sealing jacket  103  is wrapped around the ink container proper  101 , the two perforations reach the virtually the bottom edge (tear stop points  512 ) of the ink container proper  101 . The first and second adherent portion  110  and  111  of this embodiment are the same as those of the first embodiment; they are positioned so that as the sealing jacket  103  is wrapped around the ink container proper  101 , they will be on the two lateral surfaces (two surfaces contiguous to surface with ink outlet  102 ) of the ink container proper  101 , which oppose each other, sandwiching the surface with the ink outlet  102 . 
   Next, the sealing member  105  will be described. The sealing member  105  is square and is formed of film. It is adhered to the ink container proper  101  so that it seals the air vent  104 . The sealing member  105  should be peeled before the ink container  100  is mounted into an ink jet recording apparatus (unshown). Therefore, semipermanent adhesive or thermal welding is used as the means for attaching the sealing jacket  103  to the ink container proper  101 . The sealing member  105  is attached to the sealing jacket  103  with the use of such an adhesive, or a thermal welding method, that makes the adhesive strength between the sealing member  105  and sealing jacket  103  greater than the force necessary to remove the sealing member  105  from the air vent  104 . This is done in order to accomplish two objectives, that is, the unsealing of the ink container  100  and the unsealing of the air vent, by a single action, that is, by simply peeling the portion of the sealing jacket  103  between the two perforations. The details of the unsealing of this embodiment of an ink container in accordance with the present invention will be described later. 
   Next, the method for unsealing this embodiment of an ink container in accordance with the present invention will be described. The unsealing method will be described up to the stage at which the air vent is unsealed, and the processes thereafter will be not be described because they are the same as those for the first embodiment. 
   The ink container is to be unsealed in the following manner. First, a user is to grasp the tab  500  of the sealing jacket  103 , and pull it to sever the sealing jacket  103 , while peeling the sealing jacket  103  in the direction in which the sealing jacket  103  is wrapped around the ink container proper  101 . The sealing jacket  103  is provided with the two perforations  510  along which the sealing jacket  103  is easily severable. The two perforations  510  extend from the two ends (tear start points) of the base portion of the tab  500 . Thus, as the user grasps the tab  500  and pulls it in the direction in which the sealing jacket  103  is wrapped, the sealing jacket  103  will easily tear along the perforations  510 , allowing the portion of the sealing jacket  103  between the two perforations to be easily peeled. During this process, the user can assure him/herself, by finding the perforations, that the sealing jacket  103  is being peeled in the correct direction. 
   As the portion of the sealing jacket  103  between the two perforations is peeled to the position of the sealing member  105 , the sealing member  105  begins to be peeled away from the ink container proper  101  along with the sealing jacket  103 , exposing the air vent  104 . This occurs because the adhesive strength between the sealing member  105  and sealing jacket  103  is greater than that between the sealing member  105  and ink container proper  101 , and therefore, the sealing member  105  remains stuck to the sealing jacket  103  as the sealing jacket  103  is peeled. The sealing member  105  is glued to the ink container proper  101  firmly enough to keep the air vent  104  sealed. Thus, as the sealing jacket  103  is peeled to the position of the sealing member  105 , the force being applied to the sealing jacket  103  to peel the sealing jacket  103  must be increased. Therefore, unless a certain measure is taken, the hand of the user pulling the tab  500  will be let go jerkingly and uncontrollably, abruptly peeling the portion of the sealing jacket  103  which comes after the sealing member  105 , as the same time as the sealing member  105  is completely peeled. In the case of this embodiment, however, there is the first adherent portion  110  close to the ends  512  of the perforations  510 , and the first adherent portion  110  functions as the stopper for controlling the jerky movement of the user&#39;s hand. In other words, the first adherent portion  110  can temporarily halt the peeling of the sealing jacket  103  to prevent the following problem. That is, if the ink outlet  102  is unsealed, with the user&#39;s hand moving at the same velocity as the velocity at which it began to move due to the sudden reduction in the resistance to the force applied by the user&#39;s hand to the tab  500  to peel the portion of the sealing jacket  103  having the sealing member  105 , ink will be splashed. With the presence of the first adherent portion  110 , the jerky movement of the user&#39;s hand is prevented from continuing. 
   Up to the above described stage, this unsealing method can be easily carried out by anybody, because all that has to be done is to grasp and pull the tab  500  to peel the sealing jacket  103 . 
   Next, the process of peeling of the first adherent portion  110 , process of unsealing of the ink outlet  102 , and process of peeling of the second adherent portion  111 , are carried out. These processes and the effects thereof are the same as those for the first embodiment; in other words, the ink container  100  can be easily unsealed without splashing ink. 
   Incidentally, the employment of the sealing member  105  is not mandatory. In other words, the air vent  105  may be directly sealed by the sealing jacket  103 . 
   Embodiment 5 
   Next, referring to  FIG. 15 , the fifth embodiment of an ink container in accordance with the present invention will be described. This ink container  100  is similar to the first and fourth embodiments of the present invention, except that the sealing jacket  103  of this ink container  100  is different from that of the fourth embodiment. Thus, this embodiment will be described regarding only the portion of the unsealing method involving the sealing jacket  103  and the portion of the ink container proper  101  covered with the sealing jacket  103 .  FIG. 15(   a ) is a perspective view of this embodiment of an ink container in accordance with the present invention;  FIG. 15(   b ), a side view of the same;  FIG. 15(   c ), the frontal plan view of the same; and  FIG. 15(   d ) is an enlarged view of the cut interval change point, and its adjacencies, of the perforations of this embodiment of a sealing jacket  103 . 
   First, referring to  FIG. 15 , the sealing jacket  103  itself will be described. The sealing jacket  103  comprises a wrapping belt portion  120  and a cap  121  formed of the same material as those for the first and fourth embodiments. It is similar to the fourth embodiment in shape, inclusive of its tab  500 . The sealing jacket  103  is provided with a pair of perforations  510 , which extend from the ends (starting points of perforation  511 ) of the base line of the tab  500 , in the direction parallel to the direction in which the sealing jacket  103  is wrapped around the ink container proper  101 , long enough to reach the adjacencies (ends points of perforations  512 ) of the bottom edge of the surface of the ink container proper  101  contiguous to the surface of the ink container proper  101  having the air vent  104 , extending-across the two surfaces. Each perforation  510  is has two sections different in the cut interval. The two sections are separated at a cut interval change point  513 . In other words, the section between the tear starting point  511  and cut interval change point  513 , and the section between the cut interval change point  513  and the tear end point  512 , are different in the cut interval, as shown in  FIG. 15(   d ). That is, each cut interval  514  of the section of the perforation between the starting point  511  and cut interval change point is shorter and each cut interval  515  of the rest of the perforation, that is, the section of the perforation between the cut interval change point  513  and tear end point  512 . Therefore, the sealing jacket  103  is easier to tear along the former than the latter. The sealing member  105  is attached to the portion of the sealing jacket  103  between the two perforations, with the use of such an adhesive, or thermal welding method, that makes the adhesive strength between the sealing member  105  and sealing jacket  103  greater than the adhesive strength between the sealing member  105  and the ink container proper  101  (more specifically, portion which surrounds air vent  104 ). The adherent portion  600  is positioned so that the rear edge of the adherent portion  600 , in terms of the direction in which the sealing jacket  103  is to be peeled, approximately coincides with the end point  512  of each perforation. Since the adherent portion  600  is also to be peeled when unsealing the ink container  100 , it is glued to the ink container proper  101  with the use of such an adhesive, or thermal welding method, that allows the adherent portion  600  to be easily peeled. 
   Next, the method for unsealing this embodiment of an ink container in accordance with the present invention will be described. Herein, the method will be described up to the stage in which the tearing of the sealing jacket  103  along the perforations is completed. Since the processes thereafter for unsealing the ink container  100  are the same as those for the first embodiment, they will not be described. 
   The ink container  100  is unsealed in the following manner. First, in order to begin unsealing the sealing jacket  103 , a user is to grasp the tab  500  of the sealing jacket  103  and pull it in the direction parallel to the direction in which the sealing jacket  103  is wrapped around the ink container proper  101 ; the sealing jacket  103  is peeled by tearing the sealing jacket  103  along the two perforations  510 , which extend from the base portion (tear start point  511 ) of the tab  500 . As the tab  500  is pulled in the direction parallel to the direction in which the sealing jacket  103  is wrapped, the sealing jacket  103  easily tears along the two perforations  510 , allowing the portion of the sealing jacket  103  between the two perforations to be easily peeled. During this process, the user should confirm the presence of the perforations at the points at which the sealing jacket  103  is being torn, because this confirmation assures the user that the sealing jacket  103  is being properly torn. 
   Once the peeling of the portion of the sealing jacket  103  between the two perforations progresses to the location of the sealing member  105 , the sealing member  105  begins to be peeled from the ink container proper  101  along with the portion of the sealing jacket  103  between the two perforations, exposing the air vent  104 . This occurs because the sealing member  105  is adhered to the sealing jacket  103  and ink container proper  101  in such a manner that the adhesive strength between the sealing member  105  and sealing jacket  103  becomes greater than that between the sealing member  105  and ink container proper  101  (more specifically, portion around air vent  104 ), and therefore, the sealing member  105  remains attached to the sealing jacket  103 . 
   The amount of force necessary to peel the sealing member  105  from the ink container proper  101  is greater than the amount of force necessary to tear the sealing jacket  103  along the two perforations. Therefore, the user will exert a greater amount of muscular force while peeling the sealing member  105 . Then, as soon as the sealing member  105  is completely peeled, the amount of force necessary to peel the sealing jacket  103  suddenly reduces, even through the user is still exerting muscular force by the amount necessary to peel the sealing member  105 . Thus, unless a certain measure is taken, the user&#39;s hand jerkingly moves while pulling the sealing jacket  103 . Consequently, the portion of the sealing jacket  103  between the two perforations after the sealing member  105  will be yanked away. In the case of this embodiment, however, each perforation has two sections different in cut interval. Further, the cut interval change point  513 , which divides the perforation into the two sections different in cut interval, is positioned so that it will be on the surface of the ink container proper  101  contiguous to the surface of the ink container proper  101  having the air vent  104 . Therefore, the portion of the sealing jacket  103  corresponding to the cut interval change point  513  functions as the stopper for temporarily halting the unsealing of the ink container  100 , preventing therefore the yanking of the sealing jacket  103  resulting from above described the jerky movement of the user&#39;s hand. More specifically, the cut intervals  514  in the section of each perforation between the tear start point  511  and cut interval change point  513  are relatively short, making it relatively easy to tear the sealing jacket  103  along the perforation, whereas the cut intervals  515  in the section of the perforation between the cut interval change point  513  and end point  512  are relatively long, increasing the amount of the force necessary to tear the sealing jacket  103  along this section of the perforation. Thus, the abrupt peeling of the sealing jacket  103  by the above described jerky movement of the user&#39;s hand is stopped by the difference in the amount of force necessary to tear the sealing jacket  103  along the perforation between the two sections of the perforation. In other words, the jerky movement of the user&#39;s hand never lasts long enough to peel even the portion of the sealing jacket  103  corresponding to the ink outlet  102 . Therefore, the problem that ink is splashed by the abrupt unsealing of the ink outlet  102  does not occur. 
   After the abrupt tearing of the sealing jacket  103  is stopped by the portion of the sealing jacket  103  having the cut interval change points  513  of the perforations, the user is to start again to peel the portion of the sealing jacket  103  between the two perforations while tearing the sealing jacket  103  along the perforations, to the end points of the perforations  510 . As described above, a relatively larger amount of force is required to tear the sealing jacket  103  along the section of the perforation between the cut interval change point  513  and the end point  512 , and this section is made long enough, in terms of the direction in which the sealing jacket  103  is wrapped around the ink container proper  101 , to make the user realize that this portion of the sealing jacket  103  should be extra carefully peeled, that is, without yanking. Then, while the user is gradually peeling this portion of the sealing jacket  103 , the user will accurately sense the amount of force necessary to peel the rest of the sealing jacket  103 , being therefore prevented from applying an excessive amount of force; in other words, the user is prevented from jerkingly peeling the remaining portion of the sealing jacket  103 . 
   As the portion of the sealing jacket  103  between the two perforations is gradually peeled to the end points of the  512  of the perforations, the sealing member  103  loses it endless form. Thus, the resistance to the force applied to the sealing jacket  103  by the user to peel it suddenly disappears, which would have caused the user&#39;s hand to jerkingly accelerate in the direction in which the user was pulled the sealing jacket  103 . In the case of this embodiment, as described above, the user is not applying an excessive amount of force to the sealing jacket  103 . Therefore, even when the resistance disappear, the user&#39;s hand does not jerkingly accelerate. After the completion of the peeling of the portion of the sealing jacket  103  between the two perforations, the ink outlet  102  is to be unsealed. 
   As is evident from the above description, all that is necessary up to this point of the method for unsealing this embodiment of an ink container in accordance with the present invention is to grasp the tab  500  and pull it to peel away the sealing jacket  103 . Therefore, anybody can easily perform the task. 
   Thereafter, the process for unsealing of the ink outlet  102 , and the process for peeling the adherent portion  600 , are to be carried out. These processes and the effects thereof are the same as those for the first embodiment; in other words, the ink container  100  can be easily unsealed without splashing ink. 
   As described above, the present invention relates to a liquid container jacket for sealing the liquid outlet of a liquid container. According to one of the characteristic aspects of the present invention, a liquid container sealing jacket is provided with a minimum of two portions (first to fourth embodiments) by which it is attached to the liquid container, or a combination of an adherent portion and a tearing means (fifth embodiment) requiring a predetermined amount of force to tear it, which are independently disposed in a manner to sandwich the liquid outlet of the liquid container in terms of the direction in which the sealing jacket is to be peeled. Therefore, the length of the adherent portion to be peeled first (first to fourth embodiments), or the length of the tearing means (first embodiment), makes it possible for the user to recognize the amount of force necessary to peel the sealing jacket, preventing thereby the sealing jacket from being abruptly peeled away by the application of an excessive amount of force. 
   According to another aspect of the present invention, the portion of the sealing jacket corresponding in position to the liquid outlet is not adhered to the surface of the liquid container. Therefore, as soon as the peeling of the first adherent portion of the sealing jacket (first to fourth embodiments), or the tearing means (fifth embodiment), is completed, the liquid outlet can be unsealed. As described above, during this process, it does not occur that the sealing jacket is abruptly peeled. Therefore, the phenomenon that liquid in or around the liquid outlet is splashed does not occur. Further, the liquid outlet becomes open as the amount of force necessary to peel suddenly reduces to zero, giving the user the sense of completion that the liquid outlet has just been unsealed. 
   According to another aspect of the present invention, in the case of this sealing jacket, the second adherent portion of the sealing jacket (first to fourth embodiments), or the sole adherent portion of the sealing jacket (fifth embodiment), functions as the stopper for temporarily halting the peeling movement of the user, preventing the sealing member from being abruptly peeled in a single quick stroke, preventing therefore the ink adhering to the sealing jacket from being splashed. 
   According to another aspect of the present invention, the sealing jacket can be peeled away simply by grasping the tab and pulling it. Therefore, an ink container fitted with the sealing jacked in accordance with the present invention can be easily unsealed by anybody. 
   While the invention has been described with reference to the structures disclosed herein, it is not confined to the details set forth, and this application is intended to cover such modifications or changes as may come within the purposes of the improvements or the scope of the following claims.