Gas barrier polyurethane resin

• US 6,569,533 B1
• Filed: 07/19/2000
• Issued: 05/27/2003
• Est. Priority Date: 07/27/1999
• Status: Expired due to Term

• Current Assignee: Mitsui Chemicals Incorporated (Mitsui Chemicals)
• Original Assignee: Mitsui Chemicals Incorporated (Mitsui Chemicals)
• Inventors: Shiraki, Hiroyuki, Tawa, Tsutomu, Uchida, Takashi
• Primary Examiner(s): SERGENT, RABON A
• Application Number:
  US09/619,639
• Time in Patent Office: 1,042 Days
• Field of Search: 428/423.1, 428/425.5, 428/425.8, 428/425.9, 428/425.1, 524/591, 524/840, 524/839, 524/442, 528/44, 528/85
• US Class Current: 428/423.1
• CPC Class Codes: C08G 18/0823 containing carboxylate salt groups or groups forming them
• CPC Class Codes: C08G 18/12 using two or more compounds having active hydrogen in the first polymerisation step
• CPC Class Codes: C08G 18/3206 aliphatic
• CPC Class Codes: C08G 18/3228 acyclic
• CPC Class Codes: C08G 18/758 containing two or more cycloaliphatic rings
• CPC Class Codes: C08G 18/7642 containing at least two isocyanate or isothiocyanate groups linked to the aromatic ring by means of an aliphatic group having a primary carbon atom next to the isocyanate or isothiocyanate groups, e.g. xylylene diisocyanate or homologues substituted on the aromatic ring
• CPC Class Codes: C08J 2375/04 Polyurethanes
• CPC Class Codes: C08J 5/18 Manufacture of films or sheets
• CPC Class Codes: Y10T 428/31551 Of polyamidoester [polyurethane, polyisocyanate, polycarbamate, etc.]
• CPC Class Codes: Y10T 428/31591 Next to cellulosic
• CPC Class Codes: Y10T 428/31598 Next to silicon-containing [silicone, cement, etc.] layer
• CPC Class Codes: Y10T 428/31605 Next to free metal
• CPC Class Codes: Y10T 428/31609 Particulate metal or metal compound-containing

Abstract

A polyurethane resin having a total concentration of the urethane group and the urea group of not less than 15% by weight is prepared by reacting a diisocyanate component (e.g., an aromatic diisocyanate) with a diol component (e.g., a C2-8alkylene glycol). The repeating unit of the polyurethane resin may contain a constitutive unit of an aromatic or alicyclic compound. The polyurethane resin may be shaped into a film for use as a gas barrier film. The film may be a gas barrier composite film composed of a base film layer and a resin layer at least comprising the polyurethane resin. The present invention provides a polyurethane resin excellent in gas barrier properties against water vapor, oxygen, aromatics, and others, and a film containing the same.

Claims

1. An aqueous dispersion comprising a gas barrier polyurethane resin, wherein the polyurethane resin comprises a plurality of urea groups and a plurality of urethane groups, wherein the polyurethane resin has a total concentration of urea groups and urethane groups of 15% by weight or more based upon the total weight of the polyurethane resin, and wherein the polyurethane resin has both of the following characteristics:

(1) the oxygen permeability of the polyurethane resin at a thickness of 25 μ

m is 50 ml/m²·

atm·

day or less; and

(2) the ratio of oxygen permeability of the polyurethane resin at 50%RH to that at 90%RH is 1/1 to 1/2.

2. An aqueous dispersion according to claim 1, wherein the polyurethane resin contains a hydrocarbon ring unit.

3. An aqueous dispersion according to claim 2, wherein the proportion of the hydrocarbon ring unit in the polyurethane resin is 10 to 70% by weight based upon the total weight of the polyurethane resin.

4. An aqueous dispersion according to claim 1, wherein the polyurethane resin comprises at least one member selected from the group consisting of an aromatic diisocyanate, an aromatic diisocyanate, and an alicyclic diisocyanate, and a diol component comprises a C_2-8 alkylene glycol.

5. An aqueous dispersion according to claim 1, wherein the polyurethane resin comprises at least one member selected from the group consisting of a xylylene diisocyanate and a hydrogenated xylylene diisocyanate.

6. An aqueous dispersion according to claim 1, which comprises at least one member selected from the group consisting of a silane coupling agent and a layered inorganic compound.

7. An aqueous dispersion according to claim 6, wherein the proportion of the silane coupling agent is 0.1 to 30 parts by weight, and the proportion of the layered inorganic compound is 0.1 to 50 parts by weight, relative to 100 parts by weight of the polyurethane resin.

8. An aqueous dispersion according to claim 6, wherein the layered inorganic compound is water-swellable.

9. A gas barrier composite film comprising a base film layer and a resin layer formed on at least one side of the base film layer, wherein the base film layer is formed with at least one member selected from the group consisting of a plastic, a paper, a fabric, a metal and a ceramic, and the resin layer is formed from an aqueous dispersion recited in claim 1.

10. A gas barrier composite film comprising a base film layer formed with at least one member selected from the group consisting of a plastic, a paper, a fabric, a metal and a ceramic, an inorganic layer and a resin layer formed from an aqueous dispersion recited in claim 1, wherein the inorganic layer is formed on the base layer, and further the resin layer is formed on the inorganic layer.

11. A gas barrier composite film comprising a base film layer formed with at least one member selected from the group consisting of a plastic, a paper, a fabric, a metal and a ceramic, a resin layer formed from an aqueous dispersion recited in claim 1 and an inorganic layer, wherein the resin layer is formed on the base layer, and further the inorganic layer is formed on the resin layer.