Heat Cloth and Process for Producing the Same

Abstract

To provide a heat cloth which is thin and flexible; even when as a reaction of an air-permeable heat cloth proceeds, a heat generating composition becomes massive so that flexibility is lowered, or a part of an accommodating bag rides up by shrinkage and curling as caused by heat generation, well keeps the bonding and holding state so that it does not fall off easily; is supple like cloths; is excellent in flexing properties; easily and surely fits to flexible places such as elbows and knees; is able to take warmth; is applicable with good follow-up deformation properties to various places of a human body such as curved parts including shoulders, arms, a neck and feet; and hardly causes an uncomfortable feeling and a process for producing the same. A heat cloth having a heat generating composition molded body resulting from molding a heat generating composition containing surplus water as a connecting substance accommodated in an accommodating bag, wherein the accommodating bag is constituted of a substrate and a covering material; the covering material covers the heat generating composition molded body as provided on the substrate; the periphery of the heat generating composition molded body is heat sealed to form irregularities; sectional exothermic parts of a convex in which the heat generating composition molded body is accommodated are disposed while holding a sectioned part of a concave as a heat seal part; and the exothermic part is formed of a gathering of the sectional exothermic parts, which is characterized in that the substrate is substantially planar and does not contain a pocket, an accommodating division or an accommodating section; that the heat generating composition contains, as essential components, an iron powder, a carbon component, a reaction accelerator and water, does not contain a flocculant aid, a flocculant, an agglomeration aid, a dry binding material, a dry binding agent, a dry binder, a sticky raw material, a thickener and an excipient, contains surplus water so as to have a water mobility value of from 0.01 to 20, with the water in the heat generating composition not functioning as a barrier layer, and is capable of causing an exothermic reaction upon contact with air; that a volume of the heat generating composition molded body is from 0.1 to 30 cm 3 ; that a capacity of the sectional exothermic parts to a ratio of the volume of the heat generating composition molded body is from 0.6 to 1.0; that a maximum height of the sectional exothermic parts is from 0.1 to 10 mm; that a width of the sectioned part as a space between the sectional exothermic parts is from 0.3 to 50 mm; that a minimum bending resistance on the surface orthogonal to at least a thickness of the heat cloth is not more than 100 mm; that a part of the accommodating bag has air permeability; and the surroundings of the accommodating bag are sealed.

1 . A heat cloth having a heat generating composition molded body resulting from molding a heat generating composition containing surplus water as a connecting substance accommodated in an accommodating bag, wherein the accommodating bag is constituted of a substrate and a covering material; the covering material covers the heat generating composition molded body as provided on the substrate; the periphery of the heat generating composition molded body is heat sealed to form irregularities; sectional exothermic parts of a convex in which the heat generating composition molded body is accommodated are disposed while holding a sectioned part of a concave as a heat seal part; and the exothermic part is formed of a gathering of the sectional exothermic parts, characterized in that:
 1) the substrate is substantially planar and does not contain a pocket, an accommodating division or an accommodating section,   2) the heat generating composition contains, as essential components, an iron powder, a carbon component, a reaction accelerator and water, does not contain a flocculant aid, a flocculent, an agglomeration aid, a dry binder, a dry binding agent, a dry binding material, a sticky raw material, a thickener and an excipient, contains surplus water so as to have a water mobility value of from 0.01 to 20, with the water in the heat generating composition not functioning as a barrier layer, and is capable of causing an exothermic reaction upon contact with air,   3) a volume of the heat generating composition molded body is from 0.1 to 30 cm 3 ,   4) a ratio of the capacity of the sectional exothermic parts to the volume of the heat generating composition molded body is from 0.6 to 1.0,   5) a maximum height of the sectional exothermic parts is from 0.1 to 10 mm,   6) a width of the sectioned part as a space between the sectional exothermic parts is from 0.3 to 50 mm,   7) a minimum bending resistance on the surface orthogonal to at least a thickness of the heat cloth is not more than 100 mm,   8) a part of the accommodating bag has air permeability, and   9) the surroundings of the accommodating bag are sealed.   
   
   
       2 . The heat cloth according to  claim 1 , characterized in that the heat generating composition contains a component resulting from a contact treatment of a mixture containing at least an iron powder, a carbon component, a reaction accelerator and water as essential components with an oxidizing gas. 
   
   
       3 . The heat cloth according to  claim 1 , characterized in that the iron powder comprising particles, a surface of each of which is at least partially covered with an iron oxide film, the iron oxide film has a thickness of 3 nm or more, and the iron powder at least contains from 20 to 100% by weight of an active iron powder particles having a region of an oxygen-free iron component in at least one region selected from a central part region of the iron powder particles and a region beneath the iron oxide film. 
   
   
       4 . The heat cloth according to  claim 1 , characterized in that the iron powder is covered on at least a part of the surface thereof by a wustite film and contains from 20 to 100% by weight of an active iron powder having an amount of wustite of from 2 to 50% by weight in terms of an X-ray peak intensity ratio to iron. 
   
   
       5 . The heat cloth according to  claim 1 , characterized in that the heat generating composition molded body is compressed. 
   
   
       6 . The heat cloth according to  claim 1 , characterized in that in the heat seal part, the heat seal part is formed by heat sealing after temporary adhesion by an adhesive layer, and an adhesive component which constitutes the adhesive layer and a heat seal material component which constitutes the heat seal part are copresent in at least a part of the heat seal part. 
   
   
       7 . The heat cloth according to  claim 1 , characterized in that after heat sealing, at least a part of the heat generating composition molded body is moved to a temporary adhering part which is not heat sealed, thereby deadhering the temporary adhering part which is not heat sealed. 
   
   
       8 . The heat cloth according to  claim 1 , characterized in that at least a part of the air-permeable surface of the exothermic part in which the sectional exothermic parts are continuously provided is covered by an air permeability adjusting material. 
   
   
       9 . The heat cloth according to  claim 1 , characterized in that the sectioned part is provided with a perforation. 
   
   
       10 . The heat cloth according to  claim 1 , characterized in that at least a part of the sectioned part has an irregular pattern. 
   
   
       11 . The heat cloth according to  claim 1 , characterized in that the accommodating bag has a fixing measure on at least a part of the exposed surface thereof. 
   
   
       12 . The heat cloth according to  claim 11 , characterized in that the fixing measure is an adhesive layer and optionally is provided with a separator. 
   
   
       13 . The heat cloth according to  claim 12 , characterized in that the adhesive layer is a hydrophilic adhesive layer, and a packaging material between the hydrophilic adhesive layer and the heat generating composition molded body has a moisture permeability of not more than 2 g/m 2 /24 hr. 
   
   
       14 . The heat cloth according to  claim 12 , characterized in that the adhesive layer has air permeability. 
   
   
       15 . The heat cloth according to  claim 12 , characterized in that the fixing measure is a sheet-like material in which a non-stretchable portion and a stretchable portion are integrally formed in a sheet-like form, and the heat cloth is provided in the non-stretchable portion of the sheet-like material. 
   
   
       16 . The heat cloth according to  claim 1 , characterized in that the minimum bending resistance on the surface orthogonal to the thickness direction of the heat cloth is not more than 100 mm. 
   
   
       17 . The heat cloth according to  claim 1 , characterized in that the heat generating composition contains at least one member selected from additional components consisting of a water retaining agent, a water absorptive polymer, a pH adjusting agent, a hydrogen formation inhibitor, an aggregate, a fibrous material, a functional substance, a surfactant, an organosilicon compound, a pyroelectric substance, a moisturizer, a fertilizer component, a hydrophobic polymer compound, a heat generating aid, a metal other than iron, a metal oxide other than iron oxide, an acidic substance, and a mixture thereof. 
   
   
       18 . A process for producing a heat cloth having a heat generating composition molded body accommodated in an air-permeable accommodating bag, characterized in that:
 1) the accommodating bag is constituted of a substrate and a covering material; the heat generating composition molded body is formed by molding a heat generating composition containing surplus water as a connecting substance; the covering material covers the heat generating composition molded body as provided on the substrate; the periphery of the heat generating composition molded body is heat sealed to form irregularities; sectional exothermic parts of a convex in which the heat generating composition molded body is accommodated are disposed while holding a sectioned part of a concave as a heat seal part; and the exothermic part is formed of a gathering of the sectional exothermic parts,   2) the substrate is substantially planar and does not contain a pocket, an accommodating division or an accommodating section,   3) the heat generating composition contains, as essential components, an iron powder, a carbon component, a reaction accelerator and water, with an amount of water contained in the heat generating composition being from 1 to 60% by weight, does not contain a flocculant aid, a flocculent, an agglomeration aid, a dry binding material, a dry binding agent, a dry binder, a sticky raw material, a thickener and an excipient, contains surplus water so as to have a water mobility value of from 0.01 to 20, with the water in the heat generating composition not functioning as a barrier layer, and is capable of causing an exothermic reaction upon contact with air,   4) a volume of the heat generating composition molded body is from 0.1 to 30 cm 3 , and a ratio of the capacity of the sectional exothermic parts to the volume of the heat generating composition molded body is from 0.6 to 1.0,   5) a maximum height of the sectional exothermic parts is from 0.1 to 10 mm,   6) a width of the sectioned part as a space between the sectional exothermic parts is from 0.3 to 50 mm,   7) a minimum bending resistance on the surface orthogonal to at least a thickness of the heat cloth is not more than 100 mm,   8) a part of the accommodating bag has air permeability, and   9) the surroundings of the accommodating bag are sealed.   
   
   
       19 . The process for producing a heat cloth according to  claim 18 , characterized in that the substrate and the covering material each have a heat seal layer; an adhesive layer made of an adhesive is provided on at least one of the heat seal layers; and the substrate and the covering material are temporarily adhered via the adhesive layer in the surrounding of the heat generating composition molded body and then heat sealed. 
   
   
       20 . The process for producing a heat cloth according to  claim 19 , characterized in that heat sealing is carried out in a width narrower than that of the temporary adhering seal part, and thereafter, the heat generating composition is moved into a region which is not heat sealed within the temporary adhering seal part, thereby achieving deadhesion.