Container comprising an inner pouch

What claimed is:




1. A container comprising substantially dimensionally stable outer wall easily deformable inner pouch, including expandable material which, upon action agent gradually passes into foam-like or gaseous state fills space created between said inner pouch said outer wall upon discharge filing material said inner pouch, characterized that said expandable material (2) arranged between said outer wall (1) said inner pouch (3), that said agent passes through wall said inner pouch or dimensionally stable outer wall said expandable material (2); wherein said filing material not mixed with said expandable material.


2. The container according claim 1, characterized that upon action said agent, said expandable material passes least part into foam-like state.


3. The container according claim 1, characterized that said agent substance which comes into contact with said expandable material.


4. The container according claim 3, characterized that said substance water vapor or water.


5. The container according claim 1, characterized that said expandable material comprises citric acid sodium bicarbonate.


6. The container according claim 1, characterized that said inner pouch consists material which permeable water vapor predetermined degree.


7. The container according claim 1, characterized that said container produced coextrusion type blow molding process.


8. The container according claim 1, characterized that expandable material applied layer said inner pouch or internally said wall said container.

CROSS-REFERENCE TO RELATED APPLICATIONS AND CLAIM TO PRIORITY

This application claims benefit priority PCT application no. PCT/DE00/01849, filed Jun. 7, 2000, entire disclosure which incorporated herein by reference.

BACKGROUND OF THE INVENTION

The present invention relates container comprising substantially dimensionally stable outer wall easily deformable inner pouch into which pharmaceutical liquid e.g. filled that discharged with pump attached neck container. However, contents container may also cream or past which discharged opening container by compressing outer wall.

The container may shape bottle or e.g. small tube, its shape being not limited any way.

There are known containers consisting substantially dimensionally stable outer wall easily deformable inner pouch which are produced, for example, coextrusion type blow molding process consist two plastic layers that do not establish any connection with each other, i.e., inner pouch which first been inflated contact with dimensionally stable outer wall container detaches outer wall when contents container are gradually discharged.

To enable inner pouch contract accordance with discharged volume, some kind pressure compensation must take place between outer wall container contracting inner pouch. To this end, pressure compensating holes through which air enter into space between outer wall inner pouch are formed outer wall formerly known containers type question.

Although pressure compensation takes place through holes outer wall, negative pressure often created inner pouch because complete pressure compensation along whole outer circumference inner pouch does not always take place restoring forces are created by contraction inner pouch, with result that inner pouch tries return its natural form certain extent.

The negative pressure prevailing inner pouch has, turn, consequence that air enter into inner pouch, either through fine opening wall inner pouch or, for example, due leakage area possibly existing pump.

The entry air into inner pouch highly undesired because this may deteriorate quality contents container because liquid level inner pouch may fall such extent that part contents container no longer discharged, for instance because fact that liquid level falls below inlet opening suction tube pump.

BRIEF SUMMARY OF THE INVENTION

It object present invention develop container type question such manner that pressure compensation takes place more advantageous way between inner pouch which contracts upon discharge contents container substantially dimensionally stable outer wall.

In accordance with present invention, outer wall container inner pouch arranged thereinbetween expandable material which, upon discharge filling material inner pouch, fills increasing space between outer wall inner pouch.

Preferably, expandable material positioned along substantially whole space between inner pouch outer wall, but it also within scope invention that expandable material may only disposed some portions.

The outer wall inner pouch may firmly connected each other individual places, which preferably case bottom area container, so that inner pouch does not contract axial direction, but definitely contracts radial direction, which advantage complete discharge contents container. Suitably, outer wall inner pouch are also firmly interconnected area container opening, i.e. e.g. container neck, so that outwardly tight inner space created between outer wall inner pouch.

In further development invention, expandable material passes least part into foam-like state upon action agent. The foam-like expandable material fills space created between inner pouch outer wall upon discharge contents container's inner pouch accompanying contraction inner pouch expandable material supports inner pouch so that any negative pressure that might cause entry air into inner pouch virtually no longer generated pouch.

As rule, it also possible that expandable material gradually passes part into unfoamed, purely gaseous state upon action suitable agent, thereby filling space between outer wall inner pouch. In such case said space must sealed hermetically outside.

In further development invention, agent which makes pressure compensating material expand may substance which comes into contact with expandable material.

The agent/substance may water or water vapor which induces pressure compensating layer foam or expand if layer (preferably) comprises citric acid sodium bicarbonate. This advantageous development invention, it should here explicitly pointed out that said development not limited indicated expandable material substance water or water vapor which causes foaming process.

When water vapor used agent for expanding intermediate layer between outer wall inner pouch, water vapor preferably passes through inner pouch according further proposal invention. To this end, inner pouch consists material which permeable water vapor predetermined degree. For instance, very fine pores may provided which, although they are permeable water vapor, are not permeable remaining components contents container.

The agent for initiating expansion pressure compensating layer also act form outside container or introduced through outer wall into intermediate space. One possible example that that UV radiation impinges through outer wall expandable material. Such UV radiation can, e.g., take place radiation station provided for said purpose after container been filled, lead expansion intermediate space, negative pressure may generated there by contracting pouch.

As for method producing container according invention, there are no restrictions. For instance, container produced coextrusion type blow molding process three layers—one layer for inner pouch, one intermediate layer expandable material, one layer for outer wall. The outer wall inner pouch also produced separately, expandable material being applicable layer inner pouch or internally outer container. It also not necessary that outer container consists plastics. A metal sheet may e.g. also used material for outer container.

The invention shall described more detail with reference embodiment shown drawings which like numerals identify like components.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 vertical section through container, accordance with present invention;

FIG. 2 bottom view container FIG. 1, accordance with present invention;

FIG. 3 side view container FIGS. 1 2, accordance with present invention;

FIG. 4 top view container FIGS. 1–3, accordance with present invention.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

The container shown FIGS. 1–4 produced coextrusion type blow molding process three-layered tubular blank. The outer layer 1 consists relatively rigid plastic material so that said outer wall container substantially maintains its dimensional stability even if contents container are discharged. The intermediate layer 2 comprises mixture citric acid sodium bicarbonate, while inner pouch 3 consists non-rigid plastic material.

On bottom, shown FIGS. 1 2, mold cavity blow mold designed such that when blow mold closed pinch-off seam 4 substantially diamond-shaped cross section created which inner pouch 3 clamped, shown, partially, FIG. 1. The squeezing inner pouch 3 effect that inner pouch 3 cannot contract axial direction

In area opening 5 container, two vent beads 6 are formed outer wall 1 . The vent beads prevent air being entrapped during mounting bottom part pump. Vent beads 6 do not communicate with space between outer wall 1 inner pouch 3 .

The container intended receive substance which contains water. The inner pouch 3 permeable water vapor predetermined degree, water vapor initiating expansion layer 2 after having passed through wall inner pouch. A material foam gradually formed between wall 1 inner pouch 3 , foam filling space between two layers upon discharge filling substance, thereby supporting inner pouch 3 such way that no negative pressure generated therein.

As noted above, agent for initiating expansion pressure compensating layer 2 also act outside container or introduced through outer wall 1 into intermediate space. One possible example that that UV radiation 7 impinges through outer wall 1 expandable material. Such UV radiation can, e.g., take place radiation station (not shown) provided for that purpose after container inner pouch 3 been filled, lead expansion intermediate space, negative pressure may generated there by contracting pouch 3 .

As for method producing container according invention, there are no restrictions. For instance, noted above, container produced coextrusion type blow molding process three layers—one layer for inner pouch 3 , one intermediate layer expandable material 2 , one layer for outer wall 1 . The outer wall 1 inner pouch 3 also produced separately, expandable material 2 being applicable layer inner pouch 3 or internally outer container 1 . It also not necessary that outer container 1 consists plastic. A metal sheet may, for example, also used material for outer container 1 .

This description exemplary not intended limiting, since persons skill art recognize other embodiments falling within scope present invention, set forth following claims