**Abstract**

Due to the ever-increasing need for production efficiency and reliability as well as cost saving, assembly industries have been looking for a better solution compared to current methodologies. It is critically important to know that there is a solution this industry had not paid much attention and can benefit a lot due to not only historical reason but also limited knowledge management or awareness. This chapter examines and qualifies the effect of a couple of special adhesive bonding solutions on various glass plate bonding applications at appliance industry using a total solution such as dispensing system and robot. The result clearly shows its benefit over current methodologies, and also as industry trend moves toward more exterior decoration for high-end image products, this chapter should contribute on glass bonding industry not only for faster production, better efficiency, less production space, and better reliability but also for lower manufacturing cost using special adhesive bonding solutions.

**Keywords:** decorative glass, bonding strength, polyurethane hot melt, 2 component silicone

## **1. Introduction**

Ever since the appliance industry started its debut a several decades ago, appliances have evolved through various changes of performance both with their original functions and energy consumption and better high-end appearance while other parameters have come to almost achievable limit, the demand for diverse functions and appearance images that still draw hearts of multiple consumers. Now appliances have been inevitable items for every house for its convenience yet and improvement of life.

As customer's interests for high-end image products are ever increasing, and more simplified manufacturing processes with a high quality at lower cost have to be met, assembly industries have been looking for various solutions. In the beginning, they have adopted various mechanical assembly methods, one of which has been a tape method. For example, the front side design of previous major home appliances has been plastic, painted metal, or printed film on top of bare metal frame. It was difficult to achieve a high-end image with such simple design. With the use of printed glass plate, the whole image of appliances has been upgraded and met the demands of consumers who aspired better appearance of appliances; it has given more freedom to make diverse front images using all different printings at the

**Figure 1.** *Glass bonding for refrigerator and side view.*

**Figure 2.** *Glass bonding for top loading washing machine.*

**Figure 3.** *Glass bonding for front door of microwave.*

back side of glass plate. A few examples can be shown in **Figures 1**–**8**. The latest solution was a special structural adhesive that is cured by a chemical reaction. In this chapter, we would like to introduce two structural adhesive technologies, such as polyurethane hot melt technology and 2 component silicone technology, evaluate their performance and compare and analyze its difference from the current tape solution and 1 component silicone + tape solution and mechanical way on process efficiency, reliability as well as cost saving. Those appliances (or white goods) have been used at almost all the housings, and those appliances that have adopted glass plate bonding are refrigerator, washing machine, microwave, cook top, air

conditioner, dish washer, kitchen ventilation hood, styler, etc. Each appliance is explained further on the area of glass plate bonding applications. In the literature, there is only a few research on glass bonding with conventional methods, but there is not any research on glass bonding with adhesives which we focused on in this report. In this study, double-sided tape and actual test substrates were received from appliance customers, and PUR hot melt and 2C silicone adhesives were

received from Henkel laboratory.

*Glass bonding for stand-alone type dish washer.*

**Figure 5.**

**Figure 4.**

**Figure 6.**

**293**

*Glass bonding for wall type air conditioner.*

*Glass bonding of ceramic glass for microwave.*

*Global Trend of Glass Bonding for Appliance Industry Assemblies*

*DOI: http://dx.doi.org/10.5772/intechopen.90515*

*Global Trend of Glass Bonding for Appliance Industry Assemblies DOI: http://dx.doi.org/10.5772/intechopen.90515*

#### **Figure 4.**

*Glass bonding of ceramic glass for microwave.*

#### **Figure 5.** *Glass bonding for wall type air conditioner.*

**Figure 6.** *Glass bonding for stand-alone type dish washer.*

conditioner, dish washer, kitchen ventilation hood, styler, etc. Each appliance is explained further on the area of glass plate bonding applications. In the literature, there is only a few research on glass bonding with conventional methods, but there is not any research on glass bonding with adhesives which we focused on in this report. In this study, double-sided tape and actual test substrates were received from appliance customers, and PUR hot melt and 2C silicone adhesives were received from Henkel laboratory.

back side of glass plate. A few examples can be shown in **Figures 1**–**8**. The latest solution was a special structural adhesive that is cured by a chemical reaction. In this chapter, we would like to introduce two structural adhesive technologies, such as polyurethane hot melt technology and 2 component silicone technology, evaluate their performance and compare and analyze its difference from the current tape solution and 1 component silicone + tape solution and mechanical way on process efficiency, reliability as well as cost saving. Those appliances (or white goods) have been used at almost all the housings, and those appliances that have adopted glass plate bonding are refrigerator, washing machine, microwave, cook top, air

**Figure 1.**

**Figure 2.**

**Figure 3.**

**292**

*Glass bonding for refrigerator and side view.*

*Advanced Functional Materials*

*Glass bonding for top loading washing machine.*

*Glass bonding for front door of microwave.*

**2. Major appliances**

**2.2 Washing machine**

**2.3 Microwave**

frame [3].

**295**

**2.4 Cook top**

**2.1 Refrigerator**

Those requiring glass bonding are described as follows.

*Global Trend of Glass Bonding for Appliance Industry Assemblies*

*DOI: http://dx.doi.org/10.5772/intechopen.90515*

to plastic frame for top loading washing machine [2].

metal ceramic coating surface and to metal chassis [3].

Refrigerator is one of the items that can adopt glass bonding applications for various and different designs in terms of shape and function such as one door, two door, triple door, double door, French door, chest type, upright type, freezer, and kimchi refrigerator. They all can adopt glass plate bonding applications such as all front doors, inclined area between double and two triple doors, and water dispenser area on a front door and control panel. The most popular glass bonding application is a front glass plate bonding to the plastic door chassis. The below **Figure 1** shows a glass plate bonded to front door and a glass plate bonded from side view [1].

Washing machine has a few application areas that can adopt glass plate bonding applications in terms of shape and function such as top loading, front loading, and combined top and front loading, and they all can adopt a printed glass plate bonding application including control panel area. The most popular application is a glass bonding of top cover to plastic cover frame for top loading washing machine. Front loading type has a door assembled with glass and plastic frame by screws. This structure can be assembled by using a special structural adhesive eliminating screws and its related extra process to use screws. The combined front loading (on top) and top loading (on the bottom) has a function of washing clothe at the same time. The top loading type washing machine in the bottom part slides out front and do the washing. Other application is for bonding of a glass door frame to a glass door for the function of opening and throwing in a forgotten laundry while the washing machine is already running. The below **Figure 2** shows a glass bonding of top cover

Microwave has a few glass plate bonding applications. The most popular application is for bonding of front glass plate to outside front plastic door. Other applications are for bonding of glass plate to inner front metal door frame. One more application for a high-end microwave is for bonding of glass plate to bottom body frame. The below **Figure 3** shows a front door glass bonding to plastic door

Cook top uses an electrical coil with ceramic glass placed on top where they put pots and pans to cook food instead of using gas. The coil generates heat that transfer through a ceramic glass to food. It is a much more high-end image with a sleek design for easier cleaning and better health, and it has a safety advantage during cooking as people can wipe out contamination easily and do not need to inhale the burning gas. The most popular application is for bonding of ceramic glass to ceramic-coated metal frame. Other application is for bonding of ceramic glass to inner metal chassis. The below **Figure 4** shows a ceramic glass that is bonded to

**Figure 7.** *Glass bonding for kitchen ventilation hood.*

**Figure 8.** *Glass bonding for styler.*

*Global Trend of Glass Bonding for Appliance Industry Assemblies DOI: http://dx.doi.org/10.5772/intechopen.90515*
