{
  "patent_number": "US 3733309",
  "country": "US",
  "title": "How Plastic Soda Bottles Are Made Stronger Using Stretched Molecules",
  "original_title": "Biaxially oriented poly(ethylene terephthalate)bottle",
  "summary": "A 1970s invention that describes how to make lightweight, clear plastic bottles strong enough to hold carbonated drinks without exploding.",
  "what_it_does": "The patent describes a process for creating a plastic bottle made of polyethylene terephthalate (PET) that is biaxially oriented. Biaxial orientation means the plastic molecules are stretched in two directions—lengthwise and widthwise—during the manufacturing process. This alignment significantly increases the strength and impact resistance of the plastic. By achieving a specific inherent viscosity and density, the resulting bottle can withstand the high internal pressure of carbonated liquids, such as soda or beer, without deforming or bursting.",
  "what_it_does_not_cover": [
    "Does not cover bottles made from materials other than polyethylene terephthalate (PET).",
    "Does not cover non-oriented plastic containers, such as simple blow-molded jugs that lack the specific molecular alignment described.",
    "Does not cover the specific machinery or injection molding equipment used to stretch the plastic, only the resulting physical properties of the finished article."
  ],
  "filed": "1970-11-30",
  "granted": "1973-05-15",
  "expires": "1990-11-30",
  "status": "expired",
  "holder": "EI Du Pont de Nemours and Co",
  "holder_url": "https://patentbrief.org/company/ei-du-pont-de-nemours-and-co",
  "inventors": [
    {
      "name": "N Wyeth",
      "url": "https://patentbrief.org/inventor/n-wyeth"
    },
    {
      "name": "R Roseveare",
      "url": "https://patentbrief.org/inventor/r-roseveare"
    }
  ],
  "times_cited": 170,
  "tags": [
    "consumer_electronics",
    "materials",
    "mechanical"
  ],
  "abstract": "A HOLLOW, BIAXIALLY ORIENTED, THERMOPLASTIC ARTICLE, PARTICULARLY A BOTTLE, PREPARED FROM POLYETHYLENE TEREPHTHLATE WHEREIN SAID ARTICLE HAS AN INHERENT VISCOSITY OF AT LEAST 0.55, A DENSITY OF ABOUT 1.331 TO 1.402 AND A RATIO OF ARTICLE WEIGHT IN GRAMS TO VOLUME IN CUBIC CENTIMERS OF ABOUT 0.2 TO 0.005:1. SUCH ARTICLES HAVE EXCELLENT STRENGTH PROPERTIES, ARE IMPACT RESISTANT, AND ARE CAPABLE OF HOLDING LIQUIDS UNDER PRESSURES AS HIGH AS ABOUT 100 P.S.I.G. AT A TEMPERATURE OF ABOUT 50*C. WITHOUT SIGNIFICANT DEFORMATION MAKING SUCH ARTICLES USEFUL IN BOTTLING LIQUIDS UNDER PRESSURE SUCH AS BEER, CARBONATED BEVERAGES, OR AEROSOLS.",
  "url": "https://patentbrief.org/patent/us/3733309/pet-plastic-bottle",
  "markdown_url": "https://patentbrief.org/patent/us/3733309/pet-plastic-bottle/md",
  "google_patents_url": "https://patents.google.com/patent/US3733309",
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}