Methods and apparatus for applying protective films

Patent metadata

Field	Value
Publication number	US-10315405-B2
Application number	US-201615349349-A
Country	US
Kind code	B2
Filing date	Nov 11, 2016
Priority date	Jun 23, 2014
Publication date	Jun 11, 2019
Grant date	Jun 11, 2019

Abstract

An applicator die for creating undivided ribbons of polymeric film and a method of using the die to apply an emulsified polymeric material in ribbons to a fully or partially finished surface of an automobile body. In one application, the ribbon is applied as a peelable film to an automobile body and in another application, a ribbon is applied to a rocker panel as an anti-chip coating. For both applications, the applicator die has an internal gallery and an outlet slot with flared edge surfaces to emit a laminarized ribbon of polymer-based material at a distance from the target surface where the opposite edges of the ribbon have become essentially parallel.

First claim

What is claimed is:

1. A die for extruding a protective film of an undivided polymeric emulsion having a viscosity in the range of 3000 to about 12,000 centipoise adheringly onto a surface of an article of manufacture comprising:
a die body having an inlet for said emulsion and a flow passage extending from said inlet to a slot-shaped outlet formed through an elongate end surface in said die body;
said end surface having a flat linear central expanse terminating in mirror image uniformly rounded opposite corners each having a respective center of curvature;
a gallery volume formed in and extending across said passage within said body to receive said emulsion as it flows from said inlet toward said outlet, said volume having a downstream edge with 180° rounded opposite ends each having a respective center of curvature corresponding to the center of curvature of said end surface corners; and
said discharge passage having outwardly flared opposite side surfaces that extend from respective opposite tangent points on said rounded ends to respective opposite rounded corners wherein the degree of outward flare is between 5 and 50 degrees relative to the material flow direction at the center of said passage whereby the flow rate of said emulsion from said volume to and through said end surface is substantially the same across said passage end surface.

2. A die as defined in claim 1 wherein the length of the discharge outlet from end to end is approximately 85 mm.

3. The die body defined in claim 1 wherein said passage is formed in part by a shim and said die body is formed in two parts with said shim located between said two parts and wherein said shim further defines an upper edge of said gallery volume.

4. A method for adheringly applying ribbons of a protective film of polymeric material to a surface on an object comprising the steps of:
(a) positioning the extrusion die defined in claim 1 a predetermined distance from the surface;
(b) supplying an emulsified polymer based material to the die to cause a uniform, unatomized ribbon of said material to issue from the die at a speed between about 1500 mm/sec to 2000 mm/sec;
(c) moving the die relative to the surface to cause the issuing ribbon to adheringly contact the body uniformly to coat the body while maintaining said predetermined distance; said predetermined distance being such that edges of the ribbon at said distance are have become essentially parallel and no part of the die contacts the ribbon portion in adhered contact with said surface.

5. The method defined in claim 4 wherein the step of moving the die is carried out in alternatingly reverse-direction and overlapping strokes.

6. The method defined in claim 4 wherein the material is an aqueous emulsion of polyvinyl acetate and the applied ribbons are about 200 microns thick over a majority of their width.

7. The method defined in claim 4 wherein the method includes the further steps of curing the film and, thereafter, peeling the film from the body.

8. A method of protecting a portion of a painted surface of an automobile body comprising the steps of:
a. providing an uncured fluidic solution of polyvinyl acetate with a viscosity in the range of about 7,000 to about 12,000 centipoise to an inlet of an extrusion die having a flow passage with a flared outlet slot that is configured to emit an uncured ribbon of said solution with uniform edge to edge consistency in viscosity and flow rate and an outwardly lateral flare on both edges of between 5° and 50° ;
b. causing said solution to pass through said die passage to produce said ribbon thereby to cause said ribbon to expand laterally for a predetermined downstream distance from said die outlet to a maximum width wherein the edges of said ribbon are essentially parallel;
c. positioning said die at said predetermined downstream distance from said automobile body surface during extrusion to cause the ribbon to adheringly contact the surface; said distance being such that no portion of the die contacts the ribbon portion adhered to the body surface;
d. moving the die relative to the body surface at a speed which substantially matches the speed at which the ribbon is emitted from the die outlet slot; and
e. thereafter curing the applied ribbon on the automobile body.

9. The method described in claim 8 wherein the speed of movement between the die and the body surface is between about 1,500 and 2,000 mm/second and substantially equals the speed at which the ribbon is emitted from the die outlet slot.

10. The method of claim 8 wherein the dimension of the slot from side edge to side edge is approximately 85 mm and thickness of the extruded film is approximately 0.2 mm.

Assignees

• Exel Ind

Inventors

• Defillipi Michael
• Patel Vipin

Classifications

• B32B37/0046

  characterised by constructional aspects of the apparatus · CPC title

• B05D5/00 Primary

  Processes for applying liquids or other fluent materials to surfaces to obtain special surface effects, finishes or structures · CPC title

• B05C5/0254

  Coating heads with slot-shaped outlet (B05C5/0283 takes precedence) · CPC title

• B05D1/325

  Masking layer made of peelable film · CPC title

• B32B2605/08

  Cars · CPC title