AU2013204635B2

AU2013204635B2 - Glazing panel conditioning

Info

Publication number: AU2013204635B2
Application number: AU2013204635A
Authority: AU
Inventors: Paul Syfko
Original assignee: Belron International Ltd
Current assignee: Belron International Ltd
Priority date: 2009-11-16
Filing date: 2013-04-12
Publication date: 2016-09-08
Anticipated expiration: 2030-11-09
Also published as: AU2013204639A1; AU2013204639B2; AU2013204632A1; AU2013204635A1

Abstract

A conditioning agent (typically for use in repairing a flaw in a glazing panel) is contained in a sealed container which is itself disposed internally of a flexible outer walled container. Pressure applied to the outer flexible walled container can cause release of the conditioning agent from the internal conditioning agent container. The conditioning agent preparation may comprise a hygroscopic solvent (such as acetone) combined with one or more primer additives to prime the surface of the glazing panel for repair. 2.804 Reference 2a -6

Description

Glazing Panel Conditioning

The present invention relates to Conditioning of Glazing Panels, particularly to conditioning of glazing panels for repair.

Breaks, cracks or chips in glazing panels (referred to in general as flaws) can be repaired using repair devices such as vacuum repair devices similar to that disclosed in WO-A-0134373. A resin is introduced into the flaw (i.e. the chip, crack or break) and the vacuum apparatus de- gases the resin and the flaw. In order to enhance the quality of the repair it is known to treat the flaw with acetone in order to remove as much moisture as possible from the flaw, prior to filling with resin and application of the vacuum. The acetone mixes with any moisture in the flaw and enhances evaporation. Water in the flaw during repair is detrimental to the quality of the repair process. Problems can arise if the acetone (which is hygroscopic) has been contaminated by moisture prior to use.

An improved technique and device has been devised for delivering, storing and using agents for conditioning flaws or breaks in glazing panels, preparatory to conducting a repair process.

According to a first aspect of the present invention, there is provided a conditioning agent preparation for use in conditioning glazing panels for repair, the conditioning agent preparation comprising a hygroscopic acetone solvent combined with one or more primer additives to prime the surface of the glazing panel for repair, wherein the conditioning agent comprises acetone with one per cent or less by volume primer additives.

In one form, the primer additive comprises a chemical to coat the glazing panel surface to promote flow of a repair resin.

In one form, the additive material comprises Acrylic acid and/or an Organo Silane material.

According to a second aspect of the present invention, there is provided a method of conditioning a flaw in a glazing panel preparatory to repair, the method comprising applying a preparation comprising a hygroscopic acetone solvent combined with one or more primer additives to prime the surface of the glazing panel for repair, wherein the conditioning agent comprises acetone with one per cent or less by volume primer additives.

The invention will now be further described, by way of example only with reference to figure 1 which is a schematic representation of a device in accordance with the invention.

Referring to the drawings, there is shown in figure 1 a conditioning agent delivery system/dispenser in the form of an ampoule 1 comprising an elongate plastics flexible walled tube 2 having a closed end 3 and a nozzle end 4. Internally of the flexible walled plastics tube 2 is positioned an elongate frangible glass vial 5 arranged coaxially within the plastics outer tube. The frangible glass vial 5 is effectively a sealed internal container and contains a conditioning agent 6, typically in liquid form, as will be described in greater detail.

The internal sealed conditioning agent container vial 5 is disposed internally of the flexible outer walled tube 2 in a snug fit relationship in which the wall of the outer tube 2 is contiguous with the wall of the internal sealed conditioning agent vial 5 along the majority of the length of the device. This prevents the conditioning agent vial 5 from moving with respect to the outer tube 2 which could otherwise result in accidental fracture of the conditioning agent vial 5.

The flexible walled plastics tube 2 is manufactured in two-part form. A receptacle tube portion 2a has an open end 3, at the end of the tube opposite the closed end 3. The nozzle component 8 is arranged to seat within the open end 3 of the receptacle tube portion 2a. During manufacture the frangible glass vial 5 containing the conditioning agent 6 is placed into the interior of the flexible walled plastics tube 2 via the open end 7 of the tube. The nozzle component 8 is then seated into the open end 7 of the tube 2 and ultrasonically or thermally welded. Typically the nozzle component 8 is made of more rigid plastics material than the receptacle tube portion 2a.

The arrangement is such that when pinching finger pressure is applied to the longitudinal sidewalls of the flexible walled plastics tube 2, the frangible glass vial 5 is caused to fracture and the liquid form conditioning agent can pass out of the nozzle component 8 of the dispenser ampoule 1 to be delivered to the glazing panel flaw as required. The frangible glass vial 5 is therefore of thin walled glass and may for example be soda glass. A filter may be provided to prevent shards of glass passing via the nozzle component however appropriate glass selection can make the need for such a filter superfluous.

Typically the conditioning agent 6 will comprise an acetone mixture or solution. Acetone is known to be useful in enhancing evaporation and so driving moisture out of glazing panel flaws and delivery in the dispenser device of the invention aids in ensuring that the agent is ready for use and unlikely to be contaminated by ingress of moisture into the agent in the ampoule 1 during any (possibly lengthy) period of storage. The frangible glass vial 5 provides a moisture barrier and encapsulation within the dispenser in the form of the flexible walled plastics tube 2 enables the glass to be fractured and dispensing of the agent to be achieved in a safe and efficient manner, without glass fragments being dispensed from the device. The device is one shot and the conditioning agent is factory dosed and environmentally sealed. The device provides a storage and transportation container and also a dispenser/applicator device.

In certain embodiments it is preferred that the drying agent, typically a solvent (exemplified as acetone) is utilised in combination with a primer agent which is intended to, and capable of, carrying out a priming interaction with the glazing panel flaw. The priming interaction may comprise coating the surface of the flaw in a material that improves the curing of the in-filler resin, enhances the flow of the resin, or interacts with the resin to improve the adhesive strength.

In an exemplary embodiment the solution comprises 99.2% solvent (acetone) and approximately less than 1 % primer agents (for example 0.4% Acrylic Acid and 0.4% Methacryloxy Silane). Following application to the flaw, the acetone in the flaw is evaporated leaving the primer chemicals behind. The primer chemicals coat the inside surface of the flaw. In addition to enhancing the flow of resin to fully penetrate the flaw, the primer chemicals react and crosslink with the resin to improve the overall adhesive strength (increasing this by 15-18% in trials).

Other solvent variations were tried but found not to provide an optimum solution. For example Ethanol and Methanol are good solvents for water removal. However, both solvents dissolve the PVB interlayer which is typically present in a laminated vehicle windscreen, and accordingly are less preferred.

Other chemical additives were also tried. 1%, 0.5% and 0.25% windshield repair resin was tried as an additive in the Acetone. All three mixtures showed minimal benefit with respect to adhesion and wetting. It is suggested that the problem was that the resin in the solution contained photo-initiators and was therefore subject to shelf life concerns as the ampoule allowed UV thru. Organo silane and Acrylic Acid additives were also experimented with.

The silane is a coupling agent and chemically bonds to the glass surface and crosslinks into the resin polymer, increasing the adhesion of the resin. The acrylic acid also bonds to the glass and acts as an accelerator in the silane bonding process. 2%, 1% and 0.5% Organo Silane/ Acrylic Acid in Acetone were tried.

The best results were at the 1% level. 0.8% was selected as optimum in order to keep the level of Acrylic Acid <0.5% which was found to have beneficial results.

Following the application of the conditioning agent to the flaw, and elapsing of sufficient time to permit the moisture in the flaw to evaporate e driven off, the repair can be conducted by causing resin to infill and cure in the flaw. For this purpose a vacuum repair device such as shown in WOOl/343373 can be used.

Tests were conducted to compare the effect of various structural and other parameters. 1. Shelf life A test was conducted to determine the amount of moisture or water contained in a dry-out solution sample (Acetone). *Acetone is a hygroscopic material, i.e. it likes to absorb water from its environment.

Sample #1 control- new acetone straight from the bottle - 0.3% water

Sample #2 Acetone stored in plastic bottle. Sample was stored in warehouse for 4 months - 6.8% water.

Sample #3 Acetone in Glass ampoule. Sample was stored in warehouse for 4 months - 0.33% water 2. Adhesion

Testing was performed to determine the effect of the primer in the dry-out solution. * Adhesion promoters were added to dry-out solution.

Solution was applied to glass and allowed to evaporate. Glass sample were adhered with HPX-II resin. The lap shear strength was measured.

Sample #1 Control - 3350 psi

Sample # 2 Uncontrolled Acetone from hardware store (contamination) -2178 psi Sample #3 Primer in glass ampoule -3982 psi 3. Wetting and Flow characteristics A test was conducted to determine if the primer solution affected the way the resin interacts with the glass surface.

The contact angle of the resin on the glass was measured to determine wetting/flow.

Results indicate that the primed sample had a much lower contact angle then the control (untreated). This means that the primer does aid in wetting and improves the resin flow properties.

The results clearly indicate that there are technical advantages to using the dry-out in the ampoules. The addition of the primer also adds to the performance of the resin.

Throughout the specification and the claims that follow, unless the context requires otherwise, the words “comprise” and “include” and variations such as “comprising” and “including” will be understood to imply the inclusion of a stated integer or group of integers, but not the exclusion of any other integer or group of integers.

The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement of any form of suggestion that such prior art forms part of the common general knowledge.

It will be appreciated by those skilled in the art that the invention is not restricted in its use to the particular application described. Neither is the present invention restricted in its preferred embodiment with regard to the particular elements and/or features described or depicted herein. It will be appreciated that the invention is not limited to the embodiment or embodiments disclosed, but is capable of numerous rearrangements, modifications and substitutions without departing from the scope of the invention as set forth and defined by the following claims.

Claims

1. A conditioning agent preparation for use in conditioning glazing panels for repair, the conditioning agent preparation comprising a hygroscopic acetone solvent combined with one or more primer additives to prime the surface of the glazing panel for repair, wherein the conditioning agent comprises acetone with one per cent or less by volume primer additives.

2. A conditioning agent according to claim 1, wherein the primer additive comprises a chemical to coat the glazing panel surface to promote flow of a repair resin.

3. A conditioning agent according to any preceding claims, wherein the addititive material comprises Acrylic acid and/or an Organo Silane material.

4. A method of conditioning a flaw in a glazing panel preparatory to repair, the method comprising applying a preparation comprising hygroscopic acetone solvent combined with one or more primer additives to prime the surface of the glazing panel for repair, wherein the conditioning agent comprises acetone with one per cent or less by volume primer additives.