Electronicsensorsbuiltintopapercouldbeusedinarangeofwaysfrominformationstor­agetotouchscreensandmore.Electronicsensorsbuiltintocartons（纸盒）maymakeiteasiertotellwhenit’stimetothrowoutrottenmilko

　　Electronicsensorsbuiltintopapercouldbeusedinarangeofwaysfrominformationstor­agetotouchscreensandmore.

　　Electronicsensorsbuiltintocartons（纸盒）maymakeiteasiertotellwhenit’stimetothrowoutrottenmilkororangejuice.Andthat’sjustthestart.Atleastthat’sthegoalforre­searchersworkingonputtingelectronicsintopaper.They’retryingtofigureouthowtocombinetheflexibilitylow-costandrecyclabilityofpaperwiththeinformation-carryingabilityofelectronics.

　　DanielTorbjorkaphysicsgraduatestudentinFinlandhasbeenworkingontheproblem.He’spublishedareviewofthefieldinthethejournalAdvancedMaterials.

　　Muchresearchhasbeenfocusedinthisarea.Whilemostelectronicapplicationsrequirepatternedconducting（传导的）structuresconductivepapercouldbeusedinapplicationssuchasenergystoragedevices.sensorselectricheatersandothersaccordingtoTorbjork.

　　“Youcouldevenhavesomeinteractivefunctionsinmagazines”Torbjorksaid“Youcouldputasimplegameinapackage.Ifyouwantatouchscreenpressabuttonandthensomethinghappen.Sensorsinpapercouldtelluswhensomethinghasgonebad.”

　　Additionalapplicationssuchasinformationstorageandsecuritypaperhavebeensuggestedformagneticpaperscontainingmagnetite.InMassachusettsresearchershavefiguredouthowtopostavideoofsuchadeviceputintoapaperairplane.

　　Germanresearchershavealsoputelectronicchipsinpaperbanknotestodefendcounter-feiters（造伪币者）.Paperisagoodmaterialbutprintingelectronicsalsorequireslow-costmanufacturing.AsmanyUSandEuropeanpapermakerslosemarketsharetocheaperpaperfromChinathesebigpapercompaniesarelookingforaddedvalueproducts.That’swhereelectronicpaperdevicescouldmakeadifference.

　　“Themajorobstaclesarepaper’slargesurfaceroughnessandchemicalimpurities.”Torbjorksays.Butothersinthefieldthinkthatelectronicsensorsinpaperarestillfarfromtheconsumermarketplace.

　　“Idontthinkitsgoingtohappen.”saidRoyHorgan.“Youneedaconductivesurface.Itcouldbe10yearsout.Whatwearelookingforaresolutionsthatyoucancommercializeto­day.”

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