the possibility to separate the different materials once the life of the product is over represents today a new variable that designers need to take into account. Thus, taking environmental impact into account profoundly affects the design process. In the sense that now designers have to consider not only the way users will use an object, but their “design horizon” needs to broaden to consider the “use” of the object after its life.

In a few other cases designers were asked to “dress” a product already developed from the technical standpoint. In the case of Faber, in the conceptual phase the first step is the engineering design and secondly the industrial designer – external – is required to dress it. For example, they developed a new kitchen hood with a new silencer system, but the engine resulted quite cumbersome. Then a designer was asked to make a “dress” to cover it which would also give the idea of soundless softness (see picture 1). Another similar example comes from Guzzini Lighting, where the development of a new product was triggered by an explicit strategy of reducing energy-consumption costs. Once the technical solution was developed a designer was asked to put it into a complete solution.

What clearly arises is that product development is far from being a linear process. Designers, both internal and external, certainly prefer to get involved from the very beginning of the conceptual phase. During this phase, the design innovation process needs to be coordinated with the production department, the marketing department and the R&D lab. These on-going relationships are recognized to be crucial. As a designer told us, “when you see that a product which looked very promising in the conceptual phase does not come out as expected, in 99 per cent of the cases it is because there was a lack of coordination with the production during the conceptual phase”.

Figure 2 summarizes the role of designers along the phases of the product development process, in terms of interactions with the other firm’s functions and the types of knowledge involved. The process has been roughly pided into four main parts and two macro-categories: the normative sphere (how the product should be) and the positive sphere (how the project will be). Designers are involved especially in the normative sphere, in both the concept and prototyping phases. In these cases, all the types of knowledge discussed in the previous section play a part. Along with the production department, designers interact with both the marketing and R&D department if present. They are less likely to be involved during the engineering and production phases. This happens only whether some major technical problems arise related to the production process.

5. The sources of change in industrial design innovation

When both companies and designers were asked to identify the major drivers of change in the way in which design is carried out, the answer was very often a new technology, a new production technique, or a new combination of a new material coupled with a new technique. These elements are closely intertwined because the importance a material can play for design pretty much depends

on the relative technique and production processes which make the new material “malleable”. The combination of a new material with a new technique of production offers the possibility to explore new forms and solutions to functional problems within a new set of opportunities. In many cases, a new combination of material-technique has been “a concrete source of inspiration” playing a double role: supporting the technical functionality and creating the personality of a product (Ashby and Johnson, 2002).

One of the most important examples of “classic design” is the case of the chair Thonet dating back to the end of the XIX century. The origin of all the Thonet production is a new production technique. The process consisted of dampening pieces of wood to make them bendable and putting them in metal cases to desiccate them (De Fusco, 1985). As a designer explained, also in the furniture industry recently a new production technique has changed the way to use one of the oldest materials in the history of design like wood. This particular technique consists of transforming wood so that it can reproduce the look of any kind of wood. This new production technique has revolutionized industrial design in the furniture industry. 工业设计英文文献和中文翻译(3):http://www.751com.cn/fanyi/lunwen_51825.html