Abstract: In a blood transfusion system (a blood transfusion kit, a blood transfusion kit for emergency blood transfusion, or a method of using a blood transfusion kit), a flow path through which blood flows is formed using a tube having a channel therein. The flow path includes: a first path that connects an upstream path and a downstream path and has a leukocyte removal filter removing leukocytes at an intermediate position of the channel; and a second path that connects the upstream path and the downstream path and bypasses the leukocyte removal filter.

Abstract: A packaging material for blood bags includes two laminate films (I), wherein each laminate film (I) includes a base layer (Y), an inorganic deposited layer (X) formed on top of the base layer, a layer (Z1) containing a polymer of an unsaturated carboxylic acid compound polyvalent metal salt formed on top of the inorganic deposited layer (X), and a layer (Z2) containing a polymer of an unsaturated carboxylic acid compound polyvalent metal salt and a vinyl alcohol based polymer formed on top of the layer (Z1), laminating the two laminate films (I) with the layers (Z2) being laminated to form a laminate film (II), and laminating a heat seal layer on top of at least either one of the base layers (Y) of the laminate film (II). The packaging material can exhibit relatively high water vapor permeation resistance and excellent transparency and stability.

Abstract: A packaging material for blood bags includes a laminate film, wherein the laminate film includes a base layer, an inorganic deposited layer formed on top of the base layer, a layer containing a polymer of an unsaturated carboxylic acid compound polyvalent metal salt formed on top of the inorganic deposited layer, and a layer containing a polymer of an unsaturated carboxylic acid compound polyvalent metal salt and a vinyl alcohol based polymer formed on top of the layer, laminating at least two laminate films with the layers on the inside to form a laminate film, and laminating a heat seal layer on top of at least either one of the base layers of the laminate film. The packaging material can exhibit relatively high water vapor permeation resistance and excellent transparency and stability.