# US 5,700,553 A · Multilayer hydrodisintegratable film

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 5,700,553 A
- Document ID: US5700553A
- Status: Granted
- Kind: A
- Application number: 08/558,404
- Filed: 1995-11-16
- Granted: 1997-12-23
- Earliest claimed: 1995-11-16
- Assignees: Kimberly-Clark Corporation
- Inventors: Bernard Cohen; Lee Kirby Jameson; Lamar Heath Gipson; Judith Katherine Faass
- Web page: https://patentgrep.com/patent/US5700553A

## CPC

- A61L 15/62: {Compostable,} hydrosoluble or hydrodegradable materials
- A61L 15/20: containing organic materials
- A61L 15/225: {Mixtures of macromolecular compounds}
- B32B 27/22: using plasticisers
- Y10S 428/913: Material designed to be responsive to temperature, light, moisture
- Y10T 428/26: Web or sheet containing structurally defined element or component, the element or component having a specified physical dimension
- Y10T 428/266: of base or substrate
- Y10T 428/31786: Of polyester [e.g., alkyd, etc.]
- Y10T 428/31797: Next to addition polymer from unsaturated monomers
- Y10T 428/31971: Of carbohydrate
- A61L: METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES (preservation of bodies or disinfecting characterised by the agents employed A01N; preserving, e.g. sterilising, food or foodstuffs A23; preparations for medical, dental or toiletry purposes A61K)
- B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

The present invention is directed toward a multilayer film which includes a first surface layer and a second surface layer. The first surface layer is composed of materials which disintegrate when subjected to conditions present in conventional sewage systems. The second surface layer is formed from a material which is essentially inert to water, urine and other bodily fluids. Typically, the second surface layer is an extremely thin coating which provides a waterproofing effect. The multilayer film may be utilized as an outer cover in a wide variety of products such as, for example, disposable diapers and feminine care products such as sanitary napkins. In one desirable embodiment the multilayer film includes only these two layers so that the material may be flushed down a conventional toilet without clogging the sewage system because the first surface layer rapidly disintegrates in water leaving only the thin, gossamer second surface layer which can pass through the sewage system without adversely affecting it.

## Claims

### Claim 1

A multilayer film having an average thickness of less than about 50 mils, the film comprising:
a hydrodisintegratable first surface layer film comprising:
from about 7.5 to about 85 weight percent of a water dispersible polymer;
from about 7.5 to about 85 weight percent of a xerogellant; and
from about 7.5 to about 20 weight percent of a plasticizing agent; and
a substantially water impermeable second surface layer film comprising no more than 5% of the thickness of the multilayer film.

### Claim 2 (depends on 1)

The multilayer film of claim 1, wherein the hydrodisintegratable layer comprises:
from about 15 to about 75 weight percent of a water dispersible polymer;
from about 15 to about 75 weight percent of a xerogellant; and
from about 10 to about 15 weight percent of a plasticizing agent.

### Claim 3 (depends on 1)

The multilayer film of claim 1, wherein the hydrodisintegratable layer comprises:
from about 30 to about 60 weight percent of a water dispersible polymer;
from about 30 to about 60 weight percent of a xerogellant; and
from about 10 to about 15 weight percent of a plasticizing agent.

### Claim 4 (depends on 1)

The multilayer film of claim 1, wherein the hydrodisintegratable layer comprises:
from about 40 to about 50 weight percent of a water dispersible polymer;
from about 40 to about 50 weight percent of a xerogellant; and
about 12 weight percent of a plasticizing agent.

### Claim 5 (depends on 1)

The multilayer film of claim 1, wherein the water dispersible polymer is selected from the group consisting of high molecular weight amorphous polyesters having one or more ionic substituents attached thereto.

### Claim 6 (depends on 1)

The multilayer film of claim 1, wherein the xerogellant is selected from the group consisting of starch grafted polyacrylates.

### Claim 7 (depends on 1)

The multilayer film of claim 1, wherein the plasticizing agent is selected from the group consisting of glycerin, sorbitol, D-sorbitol, glucidol, sucrose, ethylene glycol, propylene glycol, diethylene glycol, polyethylene glycol, dimethyl acetamide, dimethyl sulfoxide, methyl pyrrolidene and tetramethylene sulfone.

### Claim 8 (depends on 1)

The multilayer film of claim 1, wherein the water impermeable surface layer comprises no more than 1% of the thickness of the multilayer film.

### Claim 9 (depends on 1)

The multilayer film of claim 1, wherein the water impermeable surface layer comprises no more than 0.1% of the thickness of the multilayer film.

### Claim 10 (depends on 1)

The multilayer film of claim 1, wherein the water impermeable surface layer comprises no more than 0.01% of the thickness of the multilayer film.

### Claim 11 (depends on 1)

The multilayer film of claim 1, wherein the water impermeable surface layer has an average thickness of less than 0.001 inches.

### Claim 12 (depends on 1)

The multilayer film of claim 1, wherein the water impermeable surface layer has an average thickness of less than 0.0005 inches.

### Claim 13 (depends on 1)

The multilayer film of claim 1, wherein the film consists of two layers.

### Claim 14 (depends on 1)

The multilayer film of claim 1, wherein the hydrodisintegratable first surface layer is more resistant to disintegration in synthetic urine than in water.

### Claim 15

A thin multilayer film having an average thickness of less than about 50 mils, the film comprising:
a hydrodisintegratable first surface layer film comprising:
from about 7.5 to about 85 weight percent of a water dispersible polymer selected from the group consisting of high molecular weight amorphous polyesters having one or more ionic substituents attached thereto;
from about 7.5 to about 85 weight percent of a xerogellant selected from the group consisting of starch grafted polyacrylates; and
from about 7.5 to about 20 weight percent of a plasticizing agent selected from the group consisting of glycerin, sorbitol, D-sorbitol, glucidol, sucrose, ethylene glycol, propylene glycol, diethylene glycol, polyethylene glycol, dimethyl acetamide, dimethyl sulfoxide, methyl pyrrolidene and tetramethylene sulfone; and
a substantially water impermeable second surface layer film comprising no more than 5% of the thickness of the multilayer film.

### Claim 16 (depends on 15)

The multilayer film of claim 15, wherein the film consists of two layers.

### Claim 17 (depends on 15)

The multilayer film of claim 15, wherein the water impermeable surface layer comprises no more than 1% of the thickness of the multilayer film.

### Claim 18 (depends on 15)

The multilayer film of claim 15, wherein the water impermeable surface layer comprises no more than 0.1% of the thickness of the multilayer film.

### Claim 19 (depends on 15)

The multilayer film of claim 15, wherein the water impermeable surface layer comprises no more than 0.01% of the thickness of the multilayer film.

### Claim 20

A multilayer film having an average thickness of less than about 50 mils, the film comprising:
a hydrodisintegratable first surface layer film comprising:
from about 7.5 to about 85 weight percent of a water dispersible polymer selected from the group consisting of high molecular weight amorphous polyesters having one or more ionic substituents attached thereto;
from about 7.5 to about 85 weight percent of a xerogellant selected from the group consisting of starch grafted polyacrylates; and
from about 7.5 to about 20 weight percent of D-sorbitol; and
a substantially water impermeable second surface layer film having an average thickness of less than 0.0005 inches; and
wherein the substantially water impermeable second surface layer film comprises no more than 5% of the thickness of the multilayer film.

### Claim 21 (depends on 20)

The multilayer film of claim 20, wherein the film consists of two layers.

### Claim 22 (depends on 20)

The multilayer film of claim 20, wherein the hydrodisintegratable layer is more resistant to disintegration in urine than in water.

### Claim 23 (depends on 20)

The multilayer film of claim 20, wherein the water impermeable surface layer comprises no more than 1% of the thickness of the multilayer film.

### Claim 24 (depends on 20)

The multilayer film of claim 20, wherein the water impermeable surface layer comprises no more than 0.1% of the thickness of the multilayer film.

### Claim 25 (depends on 20)

The multilayer film of claim 20, wherein the water impermeable surface layer comprises no more than 0.01% of the thickness of the multilayer film.

### Claim 26 (depends on 15)

The multilayer film of claim 15, wherein the hydrodisintegratable layer is more resistant to disintegration in urine than in water.