Manufacture of composite layer hollow molded object

[Detailed Description of the Invention]

This invention relates to the method of manufacturing the hollow fabrication object of a double layer with the hollow body and outer layer object of a synthetic resin which were fabricated separately. With the hollow fabrication object of monolayers, such as improvement in gas barrier nature, and appearance improvement, the hollow fabrication object in which the wall was generally constituted more than two-layer is used abundantly as containers for packing, such as foodstuffs and cosmetics, in order to demonstrate the effect which is not acquired. Although there are the method of blowing double layer Paris Son who did extrusion molding to a hollow body, and the method of blowing closed end double layer Paris Son who did injection molding in manufacture of the conventional double layer hollow fabrication object, In order that each of those methods might blow double layer Paris Son and might fabricate hollow bodies, such as a container and a bottle, there was a fault which cannot print between layers. In the case of the ejection blowing-in fabrication which fabricates separately a plurality of closed-end i41J Son, and it double-stratifies By the extrusion blowing-in fabrication which carries out extrusion molding of a plurality of A e Lithon simultaneously from one Gui, and it double-stratifies although not regarded in particular as questionable, Problems, like reuse of Paris of a lot of double layers which art special also to the pinch-off at the time of there being restrictions about the mobility in Di of constituent material, and blowing a double layer and Mother Son was required, and also arose by fabrication becomes difficult have arisen. Although the point about the above-mentioned mobility in Gui has been solved by adoption of the head for fabrication of specific structure, selection of resin with near fusion viscosity, etc., Different resin is in the state of indivisible one except for the case where had the same resin and double stratification is attained about reuse of Paris since Paris itself serves as a double layer, and it cannot yet reuse like the time of a monolayer, but is handling Being done as a forming loss. These artificers found out that the point which carries out blowing-in fabrication of a double layer and the Cosplayer at a double layer hollow fabrication object had a fault of the above-mentioned conventional method. Then, as a result of trying various double stratification of a hollow fabrication object, without [ a double layer and ] doing and using Son, a new manufacturing method was invented. A hollow body like the container by the synthetic resin of this invention and the outer layer object by the film of thermoplastics are fabricated separately, and are placed, these both are stuck in one within a metallic mold, and it double-stratifies. It can fabricate with the resin which can be fabricated with the extrusion blowing-in molding method generally known, an ejection blowing-in molding method, an ejection extension blowing-in molding method, etc., and the box-frame construction may not be limited to a monolayer, either, but the above-mentioned hollow body may be a double layer. The above-mentioned outer layer object is not limited to being fabricated by the state of covering all of hollow bodies, but may still be in the state of covering a part of surface, like the main portion or label of a hollow body. The resin used as this outer layer object is chosen as Conscience according to the object of double-stratifying a hollow fabrication object. When coloring in order to protect a content from ultraviolet rays, the film by the same resin as the resin which forms a hollow body can be used as an outer layer object. An outer layer object may laminate the film of several different resin, and may be multilayered again. Although the resin used for multilayering of this Flano - can be changed at any cost for the object of double stratification of a hollow fabrication object, As for the innermost layer of the multilayer film, in order to improve adhesiveness with a hollow body, it is desirable to consider it as the film by the same resin as a hollow body, or to consider it as an adhesive good resin film. Under heating and pressurization, compounding of the hollow body in the above-mentioned metallic mold and an outer layer object is performed. A result is not only bad, but adhesion on the hollow body surface becomes imperfect, and it is easy to produce wrinkles on an outer layer object only in adhesion by the fusion or softening of an outer layer object which arises by heating. However, when internal pressure is applied to a hollow body, it is expanded and an outer layer object is pressed to a metallic mold side with a hollow body wall, there is also no generating of wrinkles, and adhesion is also performed completely, and is finished and a state also becomes good. What the above-mentioned metallic mold includes the main portion of a hollow body, has a mold face with which a hollow body wall touches via an outer layer object, and has heating and a cooling method is used suitably. Grant of the pressure into a hollow body is performed with the air nozzle inserted in the neck of the hollow body. It is heated to desired temperature with a heat carrier at the time of double layer fabrication, and it is quickly cooled with a refrigerant after fabrication, and a metallic mold makes possible cycle shortening and extraction of the manufactured double layer hollow fabrication object. The hollow body of a monolayer or a double layer beforehand fabricated in the manufacturing method by this invention, From double-stratifying the outer layer object by the monolayer or a double layer film in one in a metallic mold, At the time of needlessness or composition which is reduced and makes an adhesion layer intervene in the middle, the useless measures of the conventional multilayer in Gui and the formation of Flow uniformity in Di - which does and is needed by the non-method do not cause difficulty to selection of fusion viscosity. When a hollow body is a monolayer, since pinch-off is formed at the time of the first monolayer hollow body fabrication, it does not generate poor formation, fall strength reduction, etc. of pinch-off which are easy to generate in co-extrusion double layer hollow fabrication. And Paris generated at the time of the first monolayer hollow fabrication is not afflicted in co-extrusion double layer hollow fabrication by a lot of double layer Paris where reuse is difficult, though it can reuse easily and Paris of a little covering films occurs like a usual state method. By this invention, it can print to the inner side, the outside, or the middle class of an outer layer object, and can omit again the work of label attachment etc. performed behind by this. And the hollow body which makes the great portion of dynamic function as a container or structure material is received, Cost can be low manufactured rather than the double layer hollow fabrication object by the conventional methods -- since a various protection measure can be easily made by selection of an outer layer object and the protection measure can also be given only to a required part, it is economical, and time is also shortened. The example of this invention is shown below. Example 1 Hollow fabrication was performed using high-density polyethylene of melt-index 0.35' 710 min and 0.9459/of density Crn3, and the round bottle of 300 CC was obtained. in an outer layer, 6-nylon layer of 30micro thickness and the middle class are [ the adhesion layer of 20micro thickness and a inner layer ] low-density-polyethylene layers of 30micro thickness independently -- multilayer inflation philharmonic nonuniformity preparations were made. This film was put on the above-mentioned round bottle from which Paris of an oral region or a bottom was removed, it accommodated in the metallic mold used at the time of round bottle fabrication, the blow pin was inserted in the mouth-of-a-bottle part, and the air pressure of 5 kg/crn2 was put. And tool temperature was shifted to cooling after Raise the temperature and heating for about 2 minutes to 130degreeC with heating oil, and the double layer container of about 5000 temperature was taken out. Although the line by which the product which was carried out like" 2 account and fabricated cut the pinch off part of the outer layer film remained, there was no generating of wrinkles in others and adhesion was also very good. Example 2 Using low density polyethylene of melt-index 0.8 f/IQ min, and density 0.921? / Sure 3, the tube-like object of diameter 55 A and length 400 mm was fabricated with the extrusion hollow molding method, and was taken out, and Paris removal was performed. It is melt index 2 independently? Low density polyethylene of /10 min and 0.9212/of density Kushi 3 was pushed out from T Di, and also the narrow-width film of 50 micro in thickness and width 50 Work was prepared by the black obtained by carrying out a slit. This narrow-width film was spirally twisted, as the above-mentioned tube-like object was wrapped, and it set in the metallic mold again. And 5K17-cm air pressure two was applied like Example 1, after Temperature rising(ing) tool temperature to 13000 and keeping it for 1 minute, cooling was performed, and the double layer tube-like object of the temperature of about 50 degreeC was taken out. The film end face piled up when winding spirally was also finished smoothly, and did not have wrinkles, either, and adhesion of the product produced by performing it above was also very good. Although it is what shows that a black product can be obtained by covering the surface with a black film in this example, It is t4 [ black ] like usual. It has an advantage which there is the strong point in which there are few paints and they end compared with the case where Lithon is pushed out and obtained, is increased also to it, and the material loss at the time of an extrusion machine color substitute takes out and which can perform a color substitute easily. Applicant for a patent Showa Denko 'K.K. -177