NZ210255A - Paint brush with drip guard: collar of elastomeric absorbent material - Google Patents

Description

210255 Priority Date(s): ..

Complete Specification Filetf: Cte5. .A.9^S!J/bg.

Publication Date: 19.59 P.O. Journal, No: .J3.Q1. I N.Z.No.

NEW ZEALAND Patents Act 1953 COMPLETE SPECIFICATION "DRIP GUARD FOR PAINT BRUSHES" I, OWEN ROY CORMACK, an Australian citizen of 13 Leeds Street, Rhodes, New South Wales, 2138, Australia, do hereby declare the invention, for which I pray that a Patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement : - U.Z.s*i NOV 1984 RECEiVHD 1 <1; ^ ^ J This invention relates to improvements in and relating to paint brushes.

Paint brushes are usually made from a bundle of material generally referred to as "bristles". The bristles may be of animal, vegetable or synthetic origin and this material is bound together by a band or with binding material. The band is frequently metal and is usually referred to as a "ferrule". The ferrule may be round, oval or rectangular with rounded ends depending on the shape of the handle. The handle may be inserted through the centre of the bundle of bristles or is inserted in the open end of the ferrule and held there by clinching the ferrule or by glueing or by pinning or nailing the ferrule to the handle.

The side and edge faces of the bristles are substantially planar with the outer surface of the ferrule and even after a relatively short period of time of over-shoulder height painting there is a tendancy for the paint to accumulate in the bristles in the handle end of the brush and to run over the ferrule and along the handle.

There has in consequence been a need tor a painter to exercise care in loading a brush with paint so as not to cause the paint to protrude over the line of the brush ferrule. As a result brushes are usually only partially loaded with paint in an attempt to obviate run-over. This reduces the paint load of the brush and significantly slows the speed of painting as it is necessary to increase the number of loadings which are required it the paint brush is not fully loaded. 210255 With brushes made with short length bristles the control of the amount of paint in the brush becomes very difficult. This type of brush makes painting difficult, slows the speed of painting and even with a great deal of care there is a considerable tendency in ovei—shoulder height painting for the paint to run onto the handle of the brush, the painter's hand and arm and in many cases fall on the surface below that being painted.

The invention has therefore been devised to provide a paint brush with an attachment which overcomes the aforementioned problems.

The invention according to one aspect comprises a paint brush comprising a handle, a bundle of bristles having one end secured to said handle and extending therefrom, and a collar of elastomeric absorbent material having an interconnected partly closed cell structure, said collar being on an surrounding said handle and extending beyond said handle such that an edge of said collar is in contact with the bristles to serve as a reservoir for holding paint for later use, said collar being elastic and being stretched on the handle of the brush to tightly embrace the handle without fatigue, without tearing and without substantial distortion of the shape of the cells thereof.

An embodiment of the invention will now be described with reference to the accompanying drawings in which: Fig. 1 is a front elevation of a brush with a collar positioned thereon; Fig. 2 is a side elevation of the brush and collar 3 illustrated in Fig. 1; Fig. 3 is a section on line Ill-Ill o£ Fig. 1; Fig. 4 is a perspective view of the brush and collar; and Fig. 5 is a perspective view o± the collar.

The brush comprises a bundle of bristles 1 which are held together by a band or ferrule 2. A handle 3 is inserted in the open end of the ferrule 2 and fixed thereto by nails or pins 4 and 5. Alternatively the handle may be secured in position by clinching or by adhesives. The ferrule 2 is pressed in the course of manufacture to form a number ot beads thereon. In the embodiment being described there are three beads 6, 7 and 8. These beads strengthen the ferrule and also play an important part in the guiding of the ferrule or brush head in automatic brush making and brush-finishing machines. The bead dimensions and locations on the ferrule tend to be standard throughout the brush making industry for rectangular type ferrules.

According to the invention a collar 9 ot an elastomeric absorbant material is attached to or held on the outer surface ot the ferrule 2 preferably so that its bottom 10 is in communication with the bottom outer surface of the bristles as illustrated.

As the brush is used paint flows along the bristles 1 and accumulates in the area adjacent the ferrule 2 and is held in this position by the collar 7 which forms a reservoir holding the paint for later use. The collar 7 also stops the paint from flowing over the ferrule 2 and running down the handle, wetting the hand of the user or tailing on the ^1025b surface beneath that being painted in over the shoulder painting operations.

The collar may be held in position by glueing or by a retaining band but the preferred method with brushes which are made with ferrules as described is to stretch the collar around the brush so that it is held in position on the ferrule 2 by the elasticity of the collar itself.

The selection of the materials to form the collar is an important consideration and experiments conducted by the applicant have established that it should have the following characteristics: i) it be formed of an elastomeric material having an interconnected partly closed cell structure; ii) it have sufficient elasticity so that for any given size of brush it has the ability to be stretched and remain on the handle of the brush to which it is fitted without fatigue and without tearing and without substantial distortion of the shape of its cells to the extent where its ability to readily absorb paint is inhibited; and iii) it retain sufficient pressure on the handle to prevent paint from flowing between the interface of said handle with said collar.

A suitable foam material for forming the collar of the invention is one having the following characteristics: Density (Kg/m^) 31; Tear resistance (N/m) min 400; Tensile strength (kPa) min 130; Elongation (%) min 200; and 21025b Cell count (per 25mm) 60 + 10.

Preferably the collar 2 is formed of polyester polyurethane foam material having an interconnected partially closed cell structure with a count of 55 to 60 cells per 25mm. A cell formation having these characteristics will allow paint of a viscosity lower than 1000 eeSBS^poises and preferably between 150 to 600 oori£r~t?poises to migrate through the cells in preference to breaking through the surface tension of the paint of the surface of a paint loaded collar.

Collars of different shapes can be used but the preferred shape is circular as shown in the embodiment illustrated. Circular collars are much easier to position on the brush.

In the preferred form of the invention the volume of foam in the collar is between 200% and 300% of the width of the bristles forming the brush. A collar having these characteristics will comply with the collar requirements as outlined herein.

The collar 9 is positioned on the brush handle so that approximately 7mm of the collar covers the bristles nearest the ferrule 2 with the remainder of the collar seated on the ferrule. The collar is designed to form a well or reservoir and in its stretched condition on the ferrule the outer edge 11 of the side wall 12 overlies the inner edge 13 of the side wall 14 thereby forming a funnel type recess as illustrated adjacent the bristles.

As indicated the collar provides a liquid reservoir which when the brush is loaded stores paint and the surface tension of the paint film on the surface ot the cells on the side wall 12 forms a skin imparting sufficient pressure on the paint stored within the cells to normally retain the paint in the collar and the funnel type recess 14 guides any paint on the surface of the bristles into the collar 9 when the brush is held in an above the shoulder manner.

Before use the brush is immersed to a distance of about half way up the collar in a suitable solvent eg. water in the case of water based paints and mineral turps in the case ot oil based paints. Excess solvent is removed from the collar by squeezing the collar and shaking the excess solvent from the brush. This step conditions the brush and the collar to readily receive the paint. The brush is then dipped into the paint almost to the bristle end of the collar and when the brush is inverted such as for example when painting above the shoulder height paint from the bristles gradually flows into the collar which as indicated acts as a reservoir and continued painting action sets up a pumping action by the bristles will draw this paint from the collar thereby minimising the number ot loadings required. This has the effect of speeding up painting operations and as the surfaces of the paint in the collar remote from the bristles do not alow paint within the collar to flow from the back of the collar and consequently spattering caused by paint dripping from the handle of the brush is prevented.

The invention has been described with reference to a rectangular oval ended shaped brush. It will be appreciated however that the principles of the invention can be applied to brushes ot all shapes.

Claims (9)

WHAT WE CLAIM IS: Siftgfi5

1. A paint brush comprising a handle, a bundle of bristles having one end secured to said handle and extending therefrom, and a collar of elastomeric absorbent material having an interconnected partly closed cell structure, said collar being on and surrounding said handle and extending beyond said handle such that an edge of said collar is in contact with the bristles to serve as a reservoir for holding paint for later use, said collar being elastic and being stretched on the handle of the brush to tightly embrace the handle without fatigue, without tearing and without substantial distortion of the shape of the cells thereof.

2. A paint brush as claimed in claim 1, wherein said collar is of circular configuration in relaxed state.

3. A paint brush as claimed in claim 1, wherein the collar is positioned on the brush handle so that 7 mm of the collar covers the bristles nearest the handle with the remainder of the collar positioned on the handle.

4. A paint brush as claimed in claim 1, wherein the end of the collar adjacent the bristles forms a funnel with said bristles to direct any paint on the surface of said bristles into the collar.

5. A paint brush a claimed in claim 4 wherein said end of the collar adjacent the bristles has an outwardly widening funnel shape to form said funnel. \ O •

6. A paint brush as claimed in claim 1, wherein said !fK comprises a ferrule to which said bristles are secured^said ^ a collar being elastically stretched on said ferrule. &/ — _8 - E c ji* , f# &10Z5b

7. A paint brush as claimed in claim 6 wherein said ferrule includes a plurality of spaced beads in surrounding relation thereon, said elastomeric collar being stretched on and : elastically engaging said beads.

8 . A paint brush substantially as hereinbefore described with reference to Figs. 1 to 4 of the accompanying drawings.

9. A paint brush collar as hereinbefore described with reference to Fig. 5 of the accompanying drawings. OWEN ROY CORMACK O By His Attorneys 9 Js