JPH06108632A - Improved type corner bead for dry type wall structure - Google Patents

Abstract

PURPOSE: To provide an improved nailing type corner bead having the advantage of a tape-attached type bead and capable of being economically manufactured, and to solve the wearing of the tape-attached type bead. CONSTITUTION: The corner bead 8 for drywall construction has a galvanized steel core strip 10 which is formed with a central portion, side flanges and shoulders joining the central portion and side flanges. The front face of the core strip 10 is covered with a paper layer 12 having an outer protective coating 16 thereon overlying the central portion adjoining the shoulders. A paper reinforcing layer 12 covers the back of the core strip 10 in one embodiment to minimize the thickness of the core stripe 10.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a corner bead for a dry wall structure, and more particularly to a corner bead having an outer paper layer. This application is a continuation-in-part application of application Ser. No. 07 / 541,894 filed June 21, 1990.

[0002]

Prior art and

In the corner bead of the dry-wall construction technology, generally, two types of beads, that is, "nail attachment" type and "tape attachment" type, are used. Nailed beads typically take the form of metal L-shaped strips with side flanges that meet at a central corner rib that forms a shoulder. The outer edges and outer surfaces of the side flanges, as well as the shoulders, when applied with adjoining wall surface of spackle or joint cement to cover the nail heads securing these flanges to the wall structure. Can be smooth. These nails are typically driven into the bead flange at intervals of 8 inches or less.

Another form of nailed bead has a rounded nose between the side flanges and a step shoulder is formed at the junction of the rounded nose and the side flange. The nails are driven into the side flanges and the spackle or joint cement covering the flanges is smooth against the shoulders. Leave the round nose exposed to paint later. For the following description, a corner bead having a sharp corner will be referred to as a “hard line” type, and a corner bead having a round nose will be referred to as a “soft line” type.

Tape mounted corner beads utilize paper wings instead of nails to secure the metal corner beads in place. These wings are lateral extensions of the paper cover strip and are typically joined to the metal corner beads on the outside of the side flanges by hot melt adhesive or other suitable adhesive. The metal corner angle may be formed as a hard line type or a soft line type. Wall paints for sprinkles or joint cements and corner finishes generally adhere much better to the paper cover strips of taped beads than to exposed metal of nailed beads. Also, drywall constructions that are typically covered with nailed beads are more sensitive to the appearance of crack lines along the outer edges of the side flanges than with taped beads. On the other hand,
Nailed beads have the advantage that they do not require skill to perform.

Prior to painting a wallboard adjacent to a corner covered by a corner bead, the splat or joint cement applied on the corner bead from the wall surface is sanded to smooth the wallboard to the corner bead. To form a continuous surface. In the case of taped beads, the exposed portion of the outer paper strip is normally abraded during the polishing operation, making it more difficult to obtain a smooth painted surface at the corners later. This scuff is generally most noticeable on the corner ribs of the hardline bead and the two shoulders adjacent the rounded nose of the softline bead.

[0006]

SUMMARY OF THE INVENTION The present invention provides an improved nailable corner bead that has the advantages of a taped bead and is economical to manufacture. The present invention also provides a means of solving the scrape problem of taped beads. According to the present invention, the metal corner member (hard line type or soft line type) is covered with a paper layer that is folded back at the outer edge of the corner member and adhered to the corner member. It is desirable that a paper reinforcing layer be provided on the back side of the metal corner member between the folded-back portions of the front paper layer. Thereby, the metal corner member can be made thinner. The overall cost of thin metal and reinforced backing paper is better than using metal alone at the thickness commonly used in all metal nailed corner beads (0.012 to 0.013 inch). It is economical. The corner member has a pair of shoulders as currently provided in the hardline and softline types of nailed beads. A protective coating is provided on the portion of the paper layer that covers and adjoins each shoulder to prevent scuffing during sandpaper application in preparation for painting. The protective coating has a composition to which the paint easily adheres. As part of this invention, this protective coating is also applied to the paper cover layer of the taped corner beads.

Referring to the drawings, finished hardline corner type and softline corner type nailed corner beads 8 and 9 made according to the present invention respectively include core strips 10 and 11 and paper cover strips 12 and 13, respectively. Have. The core strip is roll-formed into a hard line shape 10 having a corner rib 10a and a side flange 10b, or a soft line shape 11 having a round nose 11a, a pair of step shoulders 11b, and a side flange 11c. It is preferably galvanized steel strip. A typical hardline core strip 10 is approximately 25.4 mm wide at 90 degrees to each other.
With a (1 inch) side flange 10b, a typical softline core strip 11 is about 19.05 mm.
Round nose 11a with a radius in the range of .about.38.1 mm (3/4 to 11/2 inch) and a width of about 25.
It has a side flange 11c of 4 mm (1 inch). The corner ribs 10a of the hard line unit are typically about 1.58750 mm (0.0625 inch) high and about 3.175 mm (0.125 inch) wide. Each shoulder 11b of the softline unit typically has a width of about 3.175 mm (0.125 inches) and about 1.5875 mm (0..25 mm) from the outer edge of the round nose 11a and the adjacent side flange 11c. 0625 inches).

The cover strips 12, 13 are approximately 6.35 mm above the outer edges of the respective core strips 10, 11.
It has outer edges 12a and 13a folded back a distance of (0.25 inch). For structural economy, the backing paper strips 14, 15 for reinforcement are preferably applied to the core strips 10, 11 between the folded outer edges 12a, 13a of the respective cover strips 12, 13. Cover strips 12, 13 are 80 to 90 pounds of exposed kraft paper, as is commonly used for wallboard bonding tapes, and backing strips 14, 15 are as thick as commonly used as wallboard backing paper. About 0.4064 to 0.4
318 mm (0.016 to 0.017 inch) kraft paper is a good choice. When the backing strips 14, 15 are not used, the core strips 10, 11 typically have a thickness of about 0.3.
048 to 0.3302 mm (0.012 to 0.013
In contrast, when using a backing strip, the thickness of the core strip is about 0.1778 to 0.2286 mm (0.007 to 0.009 inch).
Good. The entire back surface of the cover strips 12, 13 and the backing strips 14, 15 are attached to the core strip 1 using a hot melt adhesive or other suitable adhesive (not shown).
Adhere to 0 and 11.

According to the present invention, a central protective coating strip 16 is applied to the outer surface of the cover strip 12 and a pair of protective coating strips 17 covers the outer surface of the cover strip 13 which covers and is adjacent to the pair of shoulders 11b. Attached. Desirably, the protective coating strips 16, 17 extend about 3.225 mm (0.125 inches) from opposite edges of the corner rib 10a and shoulder 11b, respectively. From the viewpoint of production economy, it is preferable that the width of the protective coating band is relatively narrow, but the soft line type bead 9
It will be appreciated that in this case the protective coating band may extend over the entire width of the nose 11a between the pair of shoulders 11b.

5 and 6 illustrate standard taped beads 8'and 9'in hardline and softline configurations.
7 shows protective coating bands 16 and 17 applied to the. Here, the paper cover strips are labeled 12 'and 1 respectively.
3 ', a metal core strip is designated 10' and 1
Shown by 1 '. The reference numerals of the respective parts of the core strip are the same as those in FIGS. 2 and 3 except that a dash is added.

The protective coating strips 16, 17 are made of a material that penetrates the fibers of the paper to reinforce the paper and provide surface protection against abrasion, the cover strips 12, 1 of the paper.
3 (12 ', 13') is preferably produced. For example, the coating material of the protective coating strips 16 and 17 is, for example, Synthemar (trademark) manufactured by Reichhold Chemicals (Dova, Del.).
It is preferable to use a fine particle acrylic aqueous emulsion obtained by diluting synthetic resin emulsion 40-423 or the like with water to 50%. This material can be applied with a brush, roller, or spray device. When the coating material dries, the surface of the paper coated with the coating material usually has a thickness of about 0.0
A 254 mm (0.001 inch) acrylic film or layer is formed. The thickness of this surface film or layer is about 0.1 using a suitable basecoat for protective coatings.
It can be increased to 27 mm (0.005 inch). For example, the following additive components may be added to the same acrylic resin. Ingredient Weight% Water 8.00 Ethylene glycol 1.00 Cellulose concentrated solution 16.00 Potassium tripolyphosphate (KTPP) 0.10 Defoamer 0.40 Surfactant 0.40 Aluminum silicate 12.00 Titanium dioxide 7.50 Calcium carbonate 15.00 Microbial agent 0.10 Acrylic resin 39.50 A typical cellulosic thickener is Natrosol 250HR.
It is a solution (1 ¹ / ₃ %).

When applying the hardline and softline embodiments of the nailed beads 8,9, the outer cover strips 12,13 and the backing strip 1 located under the flanges 10b, 11c of the core strip.
After driving nails 4 and 15 at regular intervals, a sprinkle or joint cement is applied from the outer surface of the lower wall plate to the ribs 10a and shoulders 11b, and is shown in phantom lines in FIGS. 2 and 4. As described above, coat the outer edge of the corner bead and the nail. Since the outer edge portion and the outer surface of each core strip 10 and 11 are covered with paper, the adhesion between the corner beads and the spackle or joint cement is good. The protective coating strips 16 and 17 then prevent harmful scuffing of the paper 12 covering the corner ribs 10a and the paper 13 covering the round nose 11a adjacent to the shoulders 11b, when sanding the sprinkle or joint cement with sandpaper. . When the relatively sharp outer edges of the metal core strips 10 and 11 are covered with the paper cover strips 12 and 13, there is also an advantage that an operator does not cut his / her hand when handling the corner beads.

The hard line type corner beads 8'and the soft line type corner beads 9'of tape type are attached by a conventional method. The soft line type joint cement or the outer paper cover strip 13 'for covering the outer paper cover strip 12' from the corner rib 10'a of the hard line type bead 8'to the outer edge of the paper cover strip 12 '. The joint cement covering from the round nose 11'a of the taped bead 9'to the outer edge of the paper cover strip 13 'is sanded to sand the surface of the joint cement against the ribs 10'a and the nose 11'a. When smoothing, the protective coating band 16 ',
17 'prevents harmful scuffing of the outer paper cover strips 12', 13 '.

The thickness of the protective coating strips 16, 17 is
It should be understood that the figures have been exaggerated somewhat for clarity. 2, 4, 5, and 6, the portion of the outer paper cover strip adjacent the protective coating strips 16, 17 is dotted to indicate the penetration of the coating material into the paper.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a hard line type corner bead formed according to the present invention, in which the thickness of each portion is exaggerated for clarity.

FIG. 2 is an enlarged detailed sectional view of a portion surrounded by a circle indicated in FIG.

FIG. 3 is a cross-sectional view of a soft line type corner bead formed according to the present invention, in which the thickness of each part is exaggerated for clarity.

FIG. 4 is an enlarged detailed sectional view of a portion surrounded by a circle indicated in FIG.

FIG. 5 is a partial cross-sectional view of a taped hardline type corner bead provided with a protective coating band according to the present invention.

FIG. 6 is a partial cross-sectional view of a tape-attaching soft line type corner bead provided with a protective coating band according to the present invention.

[Explanation of symbols]

 8 …… Hard line type nailing bead 8 ′ …… Hard line type tape attaching bead 9 …… Soft line type nailing bead 9 ′ …… Soft line type tape attaching bead 10, 11 …… Metal core strip 10a ...... Corner ribs 10b, 11c ...... Side flanges 11a ...... Nose 11b ...... Shoulders 12, 13 ...... Paper cover strips 16, 17 ...... Protective coating

 ─────────────────────────────────────────────────── —————————————————————————————— Inventor Don Eaking, Washington, USA 98053 Redmond Southeast Ace Street 23010

Claims (12)

[Claims] 1. A corner bead for a dry-wall structure, comprising a central portion, two side flanges extending laterally at substantially right angles to each other, and a shoulder portion connecting the central portion and the side flanges. Having a thickness of about 0.1778 to 0.2286 mm
A (0.007 to 0.009 inch) steel core strip, a front paper layer coating the outer surface of the core strip and bonded thereto, and a majority of the back surface of the core strip coating and bonded to it and A corner bead comprising a rear paper reinforcing layer thicker than the thickness of the core strip. 2. The corner bead according to claim 1, wherein the front paper layer is thinner than the reinforcing layer. 3. The corner bead according to claim 1, wherein the front paper layer is double-folded at an outer edge portion of the core strip. 4. The corner bead according to claim 1, wherein, on the shoulder portion and the front paper layer, a portion of the central portion along the length direction of the core strip adjacent to the shoulder portion. A corner bead characterized by having a protective coating positioned to be located at. 5. A corner bead for a dry-wall structure, comprising a central portion, two side flanges extending laterally at substantially right angles to each other, and shoulder portions connecting the central portion and the side flanges, respectively. A core strip having: a front paper layer that covers the outer surface of the core strip and is bonded to it; a back paper reinforcement layer that covers most of the back surface of the core strip and is bonded to it and is thicker than the thickness of the core strip. And provided on the front paper layer at a portion adjacent to the shoulder portion of the central portion along the length direction of the shoulder portion and the core strip, and permeates a part of the fibers of the front paper layer. On the front side of the front paper layer, the thickness is about 0.0254 to 0.127.
mm (0.001 to 0.005 inch) thin protective coating, wherein the shoulder, front paper layer and protective coating together form an outermost exposed shoulder, thereby After attaching the corner beads to the corners of the drywall, joint cement or the like can be coated with paper and applied over the entire flange portion and can be made smooth against the exposed shoulder portion. Is a corner bead that is substantially more abrasion resistant than joint cement. 6. The corner bead according to claim 5, wherein the front paper layer has a portion that covers the outer edge portion of the side flange and is folded back behind the core strip. The characteristic corner bead. 7. The corner bead according to claim 5, wherein the central portion comprises a rounded nose between the shoulder portions. 8. The corner bead according to claim 5, wherein the central portion and the shoulder portion are ribs located at the center of the core strip in the longitudinal direction. 9. The corner bead according to claim 6, wherein the back side paper reinforcing layer covers most of the back surface of the core strip between the folded back portions of the front side paper layer. The characteristic corner bead. 10. The corner bead of claim 9, wherein the core strip has a thickness of about 0.1778 to 0.2.
Corner bead made of 286 mm (0.007 to 0.009 inch) galvanized steel sheet. 11. The corner bead according to claim 1, wherein the protective coating contains an acrylic resin. 12. A corner bead for a dry-wall structure, comprising a central portion, two side flanges extending laterally at substantially right angles to each other, and shoulder portions connecting the central portion and the side flanges, respectively. A core strip having, a front paper layer covering the outer surface of the core strip and bonded to it, a back kraft paper reinforcing layer covering most of the back surface of the core strip and bonded to it, the shoulder portion and A thin protective coating formed on the front paper layer at a portion adjacent to the shoulder portion of the central portion along the length direction of the core strip, wherein the core strip has a thickness smaller than that of the reinforcing layer. About 0.
1778 to 0.2286 mm (0.007 to 0.00
9 inch) galvanized steel sheet, wherein said shoulder, front paper layer and protective coating together form the outermost exposed shoulder, whereby after attaching the corner beads to the corners of the drywall It is possible to apply joint cement or the like over the entire flange portion coated with a paper layer and make it smooth against the exposed shoulder portion, and further, the protective coating is substantially more abrasion resistant than the joint cement. A corner bead characterized by being.