A Possible New Application—A Sealant for Self-Cleaning Glass

Self-cleaning glass (SCG) can provide a constant aesthetic appearance to the buildings, where the glass is used, and also to the clear vision area for the people living or working inside the building. To maintain these conditions, it is desirable and necessary to provide SCG with an efficient photocatalytic function. Gaskets and sealants are used as perimeter seals around the glass for the weather tightness and thermal ‘Suga Test Instruments Co., Ltd, 5-4-14 Shinjuku, Shinjuku-ku, Tokyo, Japan 160-0022.

NTP*

ACRb

PUC

STPEd

SRe

И oat Glass

CF

AF

C2A8

CF

CF

S’CG-lf

CF

AF

AF

CF

CF’

S’CG-2f

CF

AF

C1A9

CF

CF

Anodized aluminum

CF

AF

AF

CF

CF

Acryl coated aluminum

CF

TF

C3A7

CF

CF

Elecirodeposiled aluminum

CF

AF

AF

C9A1

CF

Stainless steel

CF

AF

AF

CF

CF

Polyvinylchloride

CF

TF

AF

C8A2

CF

Glass fiber reinforced plastic

CF

AF

C2A8

CF

C2A8

Polycarbonate

CF

TF

AF

C9A1

C3A7

Polymethylmethacrylate

C9A1

TF

AF

AF

AF

ABS

C4A6

TF

AF

AF

AF

Pine wood

CF

TF

AF

CF

CF

TABLE 2—Adhesion progenies measured by hand peeling.

Telechelic polyacrylate sealant (silyl-lerminated polyacrylate sealant).

Vommercial water-borne acrylic sealant.

‘Commercial polyurethane sealant.

Commercial silyl-terminated polyether sealant.

Commercial silicone sealant.

fSCG: self-cleaning glass, CF or C: cohesive failure, AF or A: adhesive failure, TF or T: thin layer cohesive failure. For example, C5T2A3: 50 ‘k – of CF. 2(1 <k of TF and 30 % of AK insulation of buildings. Sealants are important, especially for high-rise or unconventionally designed buildings. Nowadays, silicone sealants are often used for this particular application, mainly due to their durability. Other conventional non-silicone sealants are not recommendable because of their insufficiently UV resistant adhesion to glass, especially to SCG which decomposes organic compounds. However, silicone sealants are not suitable for SCG because of hydrophobic contamination caused by these sealants [6]. Thus there has been no ideal sealant available on the SCG market, limiting the design of SCG buildings with gaskets. We conducted various evaluations to prove that NTP sealants are capable of providing answers to the various problems that sealants for SCG need to solve.