Shaving aid strip for razor cartridge

• US 6,301,785 B1
• Filed: 02/18/2000
• Issued: 10/16/2001
• Est. Priority Date: 02/18/2000
• Status: Expired due to Term

• Current Assignee: The Gillette Company LLC (The Procter & Gamble Company)
• Original Assignee: Gillette Company (The Procter & Gamble Company)
• Inventors: Ndou, Thilivhali T., Kwiecien, Michael J.
• Primary Examiner(s): PAYER, HWEI SIU CHOU
• Application Number:
  US09/506,628
• Time in Patent Office: 606 Days
• Field of Search: 30/340.5, 30/41, 30/50, 30/80, 30/81, 30/77, 424/73
• US Class Current: 30/41
• CPC Class Codes: B26B 21/443 Lubricating strips attached to the razor head

Abstract

The present invention is directed to a solid polymeric shaving aid strip for a razor cartridge. The shaving aid strip comprises a lubricious water-soluble polymer and a polycaprolactone, and optionally a water-insoluble polymer. It has been found that polycaprolactone improves the fabrication of the shaving aid strip, provides smoother strip surfaces and permits the inclusion of greater amounts of water-soluble polymer in the strip. It has also been found that a shaving aid strip which contains polycaprolactone releases more shaving aid during use and has better structural integrity and less swelling. The present invention is also directed to a razor cartridge which includes the aforementioned shaving aid strip.

Claims

1. A razor cartridge comprising a blade and a skin-engaging portion in proximity to said blade, said skin-engaging portion including a solid polymeric shaving aid strip comprising 55% to 90% polyethylene oxide with a molecular weight of 100,000 to 8 million daltons, 5% to 40% water-insoluble polymer selected from polystyrene, butadiene-styrene copolymer or blends thereof, and 0.5% to 50% of a polycaprolactone.

2. The razor cartridge of claim 1 wherein said shaving aid strip comprises 1% to 20% polycaprolactone.

3. The razor cartridge of claim 2 wherein said shaving aid strip comprises 1% to 10% polycaprolactone.

4. The razor cartridge of claim 1, 2 or 3 wherein said polycaprolactone has a molecular weight between about 1000 and about 80,000 daltons.

5. The razor cartridge of claim 1, 2 or 3 wherein said polycaprolactone has a molecular weight between about 30,000 and about 60,000 daltons.

6. The razor cartridge of claim 5 wherein said polycaprolactone is polycaprolactone homopolymer.

7. The razor cartridge of claim 2 wherein said polyethylene oxide comprises a blend of at least one polyethylene oxide having a molecular weight in the range of 100,000 to 500,000 daltons and at least one polyethylene oxide having a molecular weight in the range of 3 million to 8 million daltons.

8. The razor cartridge of claim 1 or 7 wherein said shaving aid strip has a homogeneous composition throughout.

9. The razor cartridge of claim 1 or 7 wherein said shaving aid strip comprises two or three adjacent lengthwise-extending portions and one of said portions comprises more of said polyethylene oxide than the other of said portions.