The present invention relates to a bag for an infusion solution particularly having a structure capable of easily mixing, at a time of use, an infusion solution with another infusion solution or a medicament other than the infusion solution which have been preliminarily independently sealed in the bag and also relates to a method of manufacturing such infusion solution bag.
In a case where it is required to prescribe an infusion solution, it has often be performed to prescribe a solution which has been prepared by mixing more than two kinds of infusion solutions or to prescribe a solution which was prepared by mixing a medicament solution other than the infusion solution with the infusion solution or dissolving powder of a medicament into the infusion solution. However, when the solution prepared by mixing the infusion solution with another infusion solution or medicament and the mixed solution is preserved, there is a fear such that the mixed solution may be denatured or discolored. Because of this reason, it is necessary to preliminarily preserve these solutions or medicaments as they are and mix them just before the prescription thereof. For example, with a dialysis solution utilized for peritoneal dialysis, it is difficult to preserve it for a long time if a pH thereof be not adjusted to weak acid, but it gives strong stimulus to a human organism in a case where it has not the neutral pH. Accordingly, it is necessary to add an alkali solution to the dialysis solution just before the prescription to make the pH thereof neutral. For example, in a case where a mixture solution of glucose infusion solution and amino acid infusion solution has been left as it is for a long time, Maillard reaction will be caused and the mixture solution will be discolored. In this example, it is also necessary to mix these solutions just before the prescription.
In view of the above matters, there has been provided an infusion solution bag having an inner space which is divided into a plurality of small chambers or sections into which infusion solutions, or infusion solution and a medicament other than the infusion solution, are accommodated respectively. These small chambers are sectioned by boundary portions which are sealed to be openable. These infusion solutions or medicament solutions stored in the respective chambers can be mixed together by opening the boundary portions just before the use.
In one type infusion solution bag of conventional structure, a shell portion of the infusion solution bag is pinched from the outer side thereof at several portions by using pinching members to divide the inner space of the bag into a plurality of small chambers or sections and various infusion solutions or the like are accommodated into these divided sections respectively. The pinching members are removed at the time of prescription to mix these infusion solutions together.
In another type of conventional structure, opposing film materials constituting both surfaces of an infusion solution bag are closed, through a heat sealing process, at boundary portions by which the inner space of the infusion solution bag is divided into a plurality of small sections. A port forming member is mounted to a part of each boundary portion, infusion solutions or other medicament solutions are accommodated in the small sections respectively, and these solutions are mixed at the infusion solution prescription time by breaking, for example, bending, the port forming member.
However, according to the conventional structures mentioned above, it is necessary to preliminarily prepare pinching members or port forming members and attach them to the infusion solution bag, resulting in increasing of troublesome working and increasing of manufacturing cost. Furthermore, it is difficult to strictly section the respective small chambers in desired shapes, and moreover, in the case of using the port forming member, since the thus formed port has a small opened area, it takes much time to complete the mixing of the infusion solutions accommodated in the respective sections.
Still furthermore, prior art provides a method in which opposing film materials, constituting both surfaces of an infusion solution bag, are closed, through a heat sealing process, with a resin film being interposed therebetween for weakening a sealing strength, at boundary portions by which the inner space of the infusion solution bag is divided into a plurality of small sections. Infusion solutions or other medicament solutions are accommodated into these small sections or chambers, and when it is required to mix these solutions in the respective small sections together, the weakly sealed part of the boundary portion is separated by applying pressure to the bag body and, then, the solutions in the respective sections are mixed through the opened boundary portion.
However, in this conventional structure, it is also necessary to prepare a resin film formed of a relatively specific material having a weakened sealing strength and dispose such resin film to a desired position of the boundary portion sectioning the respective small chambers of the bag, also involving troublesome working and increasing the manufacturing cost. Furthermore, since it is difficult to arrange the resin film having the weakened strength in a desired pattern, it is also difficult to section the small chambers so as to provide desired shapes. Still furthermore, in this structure, it is necessary to select the material for the resin film for the adjustment of the sealing strength of the boundary portion to be separated and to suitably adjust the heating temperature and pressure at the sealing time. However, it is extremely difficult to finely adjust the sealing strength of the resin film by selecting the material therefor, and moreover, in the heat sealing process, it is difficult to stably control the sealing strength by adjusting the heating temperature and pressure, which may result in that the thus manufactured infusion solution bag has no uniform sealed strength at the boundary portions to be separated.