Activator means for pre-applied adhesives

Abstract

An activator means for use in activating or re-activating adhesive and sealant compositions that have been pre-applied to a bonding surface prior to mating said bonding surface said means having a plurality of features for directly acting upon the pre-applied composition.

1 . An activator means capable of lifting an inactive pre-applied adhesive from a substrate surface and depositing said adhesive in an activated state onto said substrate surface, said activator means having a centerline axis and, perpendicular thereto, a transverse axis, said centerline axis being parallel to and aligned with direction of the relative movement of the activator means to the substrate upon which it acts during activation of the pre-applied adhesive, said activator means comprising an activator body having at least one activator face, said activator face having (a) a surface, which surface, in use, opposes the substrate surface to be acted upon, and (b) a plurality of projections extending from said surface, which projections, in use, engage the pre-applied adhesive, thereby lifting the adhesive, and deposit the adhesive in an activated state in a predetermined pattern or configuration, provided that when at least one of the projections is a linear projection which is perpendicular to the centerline axis, the length of that projection is substantially less than the width of the pre-applied adhesive to be acted upon.  
   
   
       2 . The activator means of  claim 1  wherein, in use, the pre-applied adhesive is activated concurrent with the engagement of the projections with the pre-applied adhesive.  
   
   
       3 . The activator means of  claim 1  wherein the surface of the activator face is contoured to mimic the contour of the substrate surface upon which it is intended to act.  
   
   
       4 . The activator means of  claim 1  wherein when the surface of the activator face is viewed in the direction of its centerline at its axis, the projections appear to form a solid wall which wall corresponds to the width of the pre-applied adhesive to be acted upon by the activator face.  
   
   
       5 . The activator means of  claim 1  wherein when the surface of the activator face is viewed in the direction of its centerline at its axis, the projections appear to form a wall extending between the two projections situated the furthest from and on opposite sides of the centerline axis which wall has one or more gaps.  
   
   
       6 . The activator means of  claim 5  further comprising a reciprocating means which reciprocating means moves the activator face back and forth along the transverse axis.  
   
   
       7 . The activator means of  claim 6  wherein the extent of the movement off the centerline axis imparted to the activator face by the reciprocating means is about one-half the width of the gap in each direction.  
   
   
       8 . The activator means of  claim 1  wherein the projections are selected from linear dams and ridges, chevrons, herringbones, inverted “V” shaped or crescent shaped dams or ridges, pyramids, hemispheres, hemispheroids, and cylinders and combinations thereof.  
   
   
       9 . The activator means of  claim 1  wherein the projections are in a staggered relationship along the centerline axis, but not necessarily intersecting the centerline axis, such that at least a portion of one projection overlaps with a portion of another projection when viewed in the direction of the centerline axis.  
   
   
       10 . The activator means of  claim 1  having at least one linear projection or projection having linear extensions posterior to one or more other substantially non-linear projections.  
   
   
       11 . The activator means of  claim 1  wherein the substantially non-linear projections are selected from the group consisting of inverted crescents, small inverted “V”s, hemispheres, hemispheroids, pyramids and cylinders.  
   
   
       12 . The activator means of  claim 1  wherein at least one of the projections is a linear projection or a projection having linear extensions or arms.  
   
   
       13 . The activator means of  claim 12  wherein the linear projection or extension is set at an angle relative to the centerline axis, which angle is from about 20° to about 70°.  
   
   
       14 . The activator means of  claim 12  wherein the linear projection or extension is set at an angle relative to the centerline axis, which angle is from about 30° to about 60°.  
   
   
       15 . The activator means of  claim 1  wherein the projections are aligned in a linear relationship parallel to the transverse axis.  
   
   
       16 . The activator means of  claim 1  wherein the projections are aligned in a plurality of rows, each row parallel to the transverse axis.  
   
   
       17 . The activator means of  claim 16  wherein the projections in one row are staggered relative to the projections in the neighboring.  
   
   
       18 . The activator means of  claim 1  wherein the activator face further includes one or more channels posterior to the projections.  
   
   
       19 . The activator means of  claim 18  wherein the forward face of the elements defining the channel also serve as projections lifting and moving the adhesive material.  
   
   
       20 . The activator means of  claim 18  wherein the depth and width of the channel(s) are predetermined to extrude a bead of activated adhesive of a desired width and height.  
   
   
       21 . The activator means of  claim 1  wherein the projections are selected from the group consisting of linear projections, diversionary projections and splitters and combinations thereof.  
   
   
       22 . The activator means of  claim 1  wherein the activator face is composed a metal, plastic, carbide or ceramic.  
   
   
       23 . The activator means of  claim 1  wherein the activator face is composed of a material that is heat resistant and has good heat transfer capabilities.  
   
   
       24 . The activator means of  claim 1  wherein the surface of the activator face, including the projections, has a coating thereon which coating is inert to the adhesive material to be activated.  
   
   
       25 . The activator means of  claim 24  wherein the coating is selected from polytetrafluoroethylene and a silicone material.  
   
   
       26 . The activator means of  claim 1  wherein the activator face is integral with the activator body.  
   
   
       27 . The activator means of  claim 1  wherein the activator face is attached to the activator body.  
   
   
       28 . The activator means of  claim 1  further comprising heating means.  
   
   
       29 . The activator means of  claim 1  in which the activator face is in a heat transfer relationship with a heating means.  
   
   
       30 . The activator means of  claim 1  further comprising a reciprocating means for providing reciprocating movement to the activator face.  
   
   
       31 . The activator means of  claim 1  which is associated with a reciprocating means for providing reciprocating movement to the activator face.  
   
   
       32 . The activator means of  claim 1  further comprising or being associated with a lift means for adjusting the distance between the activator face and the substrate upon which it is to work.  
   
   
       33 . The activator means of  claim 32  further comprising a sensing means which sensor means detects variations in the height of the substrate surface upon which the activator face is to work relative to the positioning of the activator face so as to enable the adjustment of the activator means.  
   
   
       34 . The activator means of  claim 1  further comprising an attachment means for integrating the activator means into an apparatus for the in-line activation of a pre-applied adhesive.  
   
   
       35 . The activator means of  claim 1  wherein the projections and any channels, if present, are molded into the activator face concurrent with the manufacture of the activator face.  
   
   
       36 . The activator means of  claim 1  wherein the activator face is made of a stock material wherein the projections and any channels, if present, are milled into stock material.  
   
   
       37 . An activator means capable of lifting an inactive pre-applied adhesive from a substrate surface and depositing said adhesive in an activated state onto said substrate surface, said activator means having a centerline axis and, perpendicular thereto, a transverse axis, said centerline axis being parallel to and aligned with direction of the relative movement of the activator means to the substrate upon which it acts during activation of the pre-applied adhesive, and said activator means comprising (a) an activator body having at least one activator face, said activator face having a surface, which surface, in use, opposes the substrate surface to be acted upon, and a linear projection extending from said activator face surface and (b) a reciprocating means for effecting a secondary movement of the activator face along the transverse axis; wherein when said linear projection is substantially perpendicular to the centerline axis, the length of the linear projection is shorter than the width of the pattern of the pre-applied adhesive on the substrate surface and the movement of the activator face along the transverse axis is sufficient to allow an effective amount of adhesive to pass the linear projection as the activator means, relative to the substrate surface, moves along the centerline axis; and wherein when said linear projection is substantially parallel with the centerline axis, the movement of the activator face along the transverse axis is sufficient to act upon an effective amount of pre-applied adhesive as the activator means, relative to the substrate surface, moves along the centerline axis.  
   
   
       38 . The activator means of  claim 37  wherein the activator face has a plurality of linear projections substantially parallel to the centerline axis.  
   
   
       39 . The activator means of  claim 37  wherein the activator face has a plurality of linear projections substantially perpendicular to the centerline axis, wherein said linear projections are co-linear or staggered along, but not necessarily intersecting with, the centerline axis, or both.  
   
   
       40 . The activator means of  claim 37  wherein the activator face has a plurality of linear projections substantially perpendicular to the centerline axis, wherein said linear projections are staggered along, but not necessarily intersecting with, the centerline axis.  
   
   
       41 . An improved method of activating a pre-applied adhesive on the surface of a substrate said method comprising the steps of passing an activator means over the pre-applied adhesive wherein the improvement lies in the use of an activating means having a centerline axis and, perpendicular thereto, a transverse axis, said centerline axis being parallel to and aligned with direction of the relative movement of the activator means to the substrate during activation, said activator means comprising an activator body having at least one activator face, said activator face having (a) a surface, which surface opposes the substrate surface being acted upon, and (b) a plurality of projections extending from said surface, which projections engage the pre-applied adhesive, thereby lifting the adhesive from the substrate and deposit the adhesive in an activated state in a predetermined pattern or configuration, provided that when at least one of the projections is a linear projection which is perpendicular to the centerline axis, the length of that projection is substantially less than the width of the pre-applied adhesive to be acted upon.  
   
   
       42 . The method of  claim 41  wherein the pre-applied adhesive is a thermoplastic adhesive and the activator means further comprises or is in a heat transfer relationship with a heating means whereby heat is transferred from the heating means to the thermoplastic adhesive by the activator face.  
   
   
       43 . The method of  claim 41  wherein the pre-applied adhesive is an encapsulated adhesive wherein the projections fracture the microcapsules containing the adhesive components and create sufficient flow within the adhesive mass to effect activation before depositing the same on the substrate.