this._printService.GetWord(printInfo).subscribe((response:any) => {
    const filename = response.headers.get('Content-Disposition').split(/[;'=]/).pop();
    saveAs(response.body, decodeURIComponent(filename))
});

GetWord(params: HttpParams): Observable<any> {
    return  this.http.get<Blob>(
            `${this.apiUrl}/DemoWordGet`,
            {
                params,
                responseType: 'blob' as 'json',
                observe: 'response',
            });
}

return this.http
    .get(`${this.apiUrl}/DemoWordGet`, {
      responseType: ResponseContentType.Blob
    })
    .map(res => {
      return {
        filename: 'filename.pdf',
        data: res.blob()
      };
    });

responseType: 'blob' as 'json'

responseType: "blob"